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The amazing potential of fungi: 50 ways we can exploit fungi industrially

Kevin D. Hyde, Jianchu Xu, Sylvie Rapior +60 more · Fungal Diversity · 2019 · 801 citations

Fungi are an understudied, biotechnologically valuable group of organisms. Due to the immense range of habitats that fungi inhabit, and the consequent need to compete against a diverse array of other fungi, bacteria, and animals, fungi have developed numerous survival mechanisms. The unique attributes of fungi thus herald great promise for their application in biotechnology and industry. Moreover, fungi can be grown with relative ease, making production at scale viable. The search for fungal biodiversity, and the construction of a living fungi collection, both have incredible economic potential in locating organisms with novel industrial uses that will lead to novel products. This manuscript reviews fifty ways in which fungi can potentially be utilized as biotechnology. We provide notes and examples for each potential exploitation and give examples from our own work and the work of other notable researchers. We also provide a flow chart that can be used to convince funding bodies of the importance of fungi for biotechnological research and as potential products. Fungi have provided the world with penicillin, lovastatin, and other globally significant medicines, and they remain an untapped resource with enormous industrial potential.

Nucleic acid-based approaches to investigate microbial-related cheese quality defects

Daniel J. O’Sullivan, Linda Giblin, Paul L.H. McSweeney +2 more · Frontiers in Microbiology · 2013 · 1,420 citations

The microbial profile of cheese is a primary determinant of cheese quality. Microorganisms can contribute to aroma and taste defects, form biogenic amines, cause gas and secondary fermentation defects, and can contribute to cheese pinking and mineral deposition issues. These defects may be as a result of seasonality and the variability in the composition of the milk supplied, variations in cheese processing parameters, as well as the nature and number of the non-starter microorganisms which come from the milk or other environmental sources. Such defects can be responsible for production and product recall costs and thus represent a significant economic burden for the dairy industry worldwide. Traditional non-molecular approaches are often considered biased and have inherently slow turnaround times. Molecular techniques can provide early and rapid detection of defects that result from the presence of specific spoilage microbes and, ultimately, assist in enhancing cheese quality and reducing costs. Here we review the DNA-based methods that are available to detect/quantify spoilage bacteria, and relevant metabolic pathways in cheeses and, in the process, highlight how these strategies can be employed to improve cheese quality and reduce the associated economic burden on cheese processors.

An overview of fermentation in the food industry - looking back from a new perspective

Shahida Anusha Siddiqui, Zeki Erol, Jerina Rugji +8 more · Bioresources and Bioprocessing · 2023 · 261 citations

Fermentation is thought to be born in the Fertile Crescent, and since then, almost every culture has integrated fermented foods into their dietary habits. Originally used to preserve foods, fermentation is now applied to improve their physicochemical, sensory, nutritional, and safety attributes. Fermented dairy, alcoholic beverages like wine and beer, fermented vegetables, fruits, and meats are all highly valuable due to their increased storage stability, reduced risk of food poisoning, and enhanced flavor. Over the years, scientific research has associated the consumption of fermented products with improved health status. The fermentation process helps to break down compounds into more easily digestible forms. It also helps to reduce the amount of toxins and pathogens in food. Additionally, fermented foods contain probiotics, which are beneficial bacteria that help the body to digest food and absorb nutrients. In today's world, non-communicable diseases such as cardiovascular disease, type 2 diabetes, cancer, and allergies have increased. In this regard, scientific investigations have demonstrated that shifting to a diet that contains fermented foods can reduce the risk of non-communicable diseases. Moreover, in the last decade, there has been a growing interest in fermentation technology to valorize food waste into valuable by-products. Fermentation of various food wastes has resulted in the successful production of valuable by-products, including enzymes, pigments, and biofuels.

Biosurfactants: Production, properties, applications, trends, and general perspectives

Leonie Asfora Sarubbo, Maria da Glória C. Silva, Ítalo José Batista Durval +5 more · Biochemical Engineering Journal · 2022 · 384 citations

Biosurfactants have become attractive microbial products in the emerging biotechnology industry due to their advantages over synthetic surfactants in terms of environmental sustainability, global public health, and the concerns of industries to produce environmentally friendly goods. The amphipathic structure of biosurfactants with hydrophilic and hydrophobic moieties enable these molecules to play a key role in emulsification, foam formation, detergency, and oil dispersion activities, which are desirable traits in different industries. Several types of biosurfactants are commercially produced for applications in the pharmaceutical and cosmetic industries while others have promising roles in the food, petroleum, and agricultural industries. In this paper, we offer an extensive review of knowledge on microbial biosurfactants accumulated over the years. We also discuss current and promising industrial applications of biosurfactants as well as the advantages and challenges for their development and applications.

Review of Green Food Processing techniques. Preservation, transformation, and extraction

Farid Chemat, Natacha Rombaut, Alice Meullemiestre +4 more · Innovative Food Science & Emerging Technologies · 2017 · 809 citations

Scientific Guidance for the submission of dossiers on Food Enzymes

EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (EFSA CEP Panel), Claude Lambré, José Manuel Barat Baviera +23 more · EFSA Journal · 2021 · 399 citations

Following a request from the European Commission, EFSA developed an updated scientific guidance to assist applicants in the preparation of applications for food enzymes. This guidance describes the scientific data to be included in applications for the authorisation of food enzymes, as well as for the extension of use for existing authorisations, in accordance with Regulation (EC) No 1331/2008 and its implementing rules. Information to be provided in applications relates to source, production and characteristics of the food enzyme, toxicological data, allergenicity and dietary exposure estimation. Source, production and characteristics of the food enzyme are first considered only for enzymes of microbial origin and subsequently for those enzymes derived from plants and for enzymes from animal sources. Finally, the data requested for toxicology, allergenicity and dietary exposure applies to all food enzymes independent of the source. On the basis of the submitted data, EFSA will assess the safety of food enzymes and conclude whether or not they present a risk to human health under the proposed conditions of use.

Domestication and Divergence of Saccharomyces cerevisiae Beer Yeasts

Brigida Gallone, Jan Steensels, Troels Prahl +16 more · Cell · 2016 · 724 citations

Physiology of Acetic Acid Bacteria and Their Role in Vinegar and Fermented Beverages

Kieran M. Lynch, Emanuele Zannini, Stuart Wilkinson +2 more · Comprehensive Reviews in Food Science and Food Safety · 2019 · 220 citations

Acetic acid bacteria (AAB) have, for centuries, been important microorganisms in the production of fermented foods and beverages such as vinegar, kombucha, (water) kefir, and lambic beer. Their unique form of metabolism, known as "oxidative" fermentation, mediates the transformation of a variety of substrates into products, which are of importance in the food and beverage industry and beyond; the most well-known of which is the oxidation of ethanol into acetic acid. Here, a comprehensive review of the physiology of AAB is presented, with particular emphasis on their importance in the production of vinegar and fermented beverages. In addition, particular reference is addressed toward Gluconobacter oxydans due to its biotechnological applications, such as its role in vitamin C production. The production of vinegar and fermented beverages in which AAB play an important role is discussed, followed by an examination of the literature relating to the health benefits associated with consumption of these products. AAB hold great promise for future exploitation, both due to increased consumer demand for traditional fermented beverages such as kombucha, and for the development of new types of products. Further studies on the health benefits related to the consumption of these fermented products and guidelines on assessing the safety of AAB for use as microbial food cultures (starter cultures) are, however, necessary in order to take full advantage of this important group of microorganisms.

Kombucha Beverage from Green, Black and Rooibos Teas: A Comparative Study Looking at Microbiology, Chemistry and Antioxidant Activity

Francesca Gaggìa, Loredana Baffoni, Michele Galiano +8 more · Nutrients · 2018 · 532 citations

Kombucha is usually obtained from the fermentation of black or green tea by a consortium of acetic acid bacteria and yeasts. In this study, kombucha was prepared from the same starter consortium using green and black teas as well as, for the first time, an infusion of rooibos leaves (Aspalathus linearis). Microbial diversity was analysed during fermentation both in the biofilm and in the corresponding kombuchas, using culture-dependent and -independent methods. Polyphenols, flavonoids, ethanol, and acids were quantified and anti-oxidant activities were monitored. All of the Kombuchas showed similarity in bacterial composition, with the dominance of Komagataeibacter spp. Beta diversity showed that the yeast community was significantly different among all tea substrates, between 7 and 14 days of fermentation and between biofilm and kombucha, indicating the influence of the substrate on the fermenting microbiota. Kombucha from rooibos has a low ethanol concentration (1.1 mg/mL), and a glucuronic acid amount that was comparable to black tea. Although antioxidant activity was higher in black and green kombucha compared to rooibos, the latter showed an important effect on the recovery of oxidative damage on fibroblast cell lines against oxidative stress. These results make rooibos leaves interesting for the preparation of a fermented beverage with health benefits.

The Application of Artificial Intelligence and Big Data in the Food Industry

Haohan Ding, Jiawei Tian, Wei Yu +6 more · Foods · 2023 · 174 citations

Over the past few decades, the food industry has undergone revolutionary changes due to the impacts of globalization, technological advancements, and ever-evolving consumer demands. Artificial intelligence (AI) and big data have become pivotal in strengthening food safety, production, and marketing. With the continuous evolution of AI technology and big data analytics, the food industry is poised to embrace further changes and developmental opportunities. An increasing number of food enterprises will leverage AI and big data to enhance product quality, meet consumer needs, and propel the industry toward a more intelligent and sustainable future. This review delves into the applications of AI and big data in the food sector, examining their impacts on production, quality, safety, risk management, and consumer insights. Furthermore, the advent of Industry 4.0 applied to the food industry has brought to the fore technologies such as smart agriculture, robotic farming, drones, 3D printing, and digital twins; the food industry also faces challenges in smart production and sustainable development going forward. This review articulates the current state of AI and big data applications in the food industry, analyses the challenges encountered, and discusses viable solutions. Lastly, it outlines the future development trends in the food industry.

Novel Bioactive Compounds From Marine Sources as a Tool for Functional Food Development

Susmita Ghosh, Tanmay Sarkar, Siddhartha Pati +3 more · Frontiers in Marine Science · 2022 · 255 citations

The marine environment is a relatively unexplored source of functional ingredients that can be used in food processing, storage, and fortification in a variety of ways. Marine microorganisms are a possible source of novel bioactive chemicals with potential human utility. Some of these microbes can live in the harsh marine environments, resulting in complex compounds with unique biological properties that can be used in several industrial and biotechnological applications. So far, several marine microorganisms (fungi, myxomycetes, bacteria, and microalgae) have been isolated that produce antioxidant, antibacterial, apoptotic, antitumoral, and antiviral chemicals. Furthermore, it emphasizes the enormous potential for marine microbes to produce very important bioactive chemicals. The main goal of this review is to provide a concise overview of several constituents of marine bioactives. Anticoagulant, anticancer, and hypocholesterolemic effects have been demonstrated for bioactive peptides extracted from fish protein hydrolysates, as well as algal fucans, galactans, and alginates. Furthermore, omega-3 fatty acids are abundant in fish oils and marine microorganisms, while potent antioxidants such as carotenoids and phenolic compounds can be found in crustaceans and seaweeds. This review focuses on the potential use of marine-derived chemicals as functional food ingredients for health maintenance and chronic disease prevention, based on their bioactive qualities.

Microbial biogeography of wine grapes is conditioned by cultivar, vintage, and climate

Nicholas A. Bokulich, J.H. Thorngate, Paul M. Richardson +1 more · Proceedings of the National Academy of Sciences · 2013 · 984 citations

Wine grapes present a unique biogeography model, wherein microbial biodiversity patterns across viticultural zones not only answer questions of dispersal and community maintenance, they are also an inherent component of the quality, consumer acceptance, and economic appreciation of a culturally important food product. On their journey from the vineyard to the wine bottle, grapes are transformed to wine through microbial activity, with indisputable consequences for wine quality parameters. Wine grapes harbor a wide range of microbes originating from the surrounding environment, many of which are recognized for their role in grapevine health and wine quality. However, determinants of regional wine characteristics have not been identified, but are frequently assumed to stem from viticultural or geological factors alone. This study used a high-throughput, short-amplicon sequencing approach to demonstrate that regional, site-specific, and grape-variety factors shape the fungal and bacterial consortia inhabiting wine-grape surfaces. Furthermore, these microbial assemblages are correlated to specific climatic features, suggesting a link between vineyard environmental conditions and microbial inhabitation patterns. Taken together, these factors shape the unique microbial inputs to regional wine fermentations, posing the existence of nonrandom "microbial terroir" as a determining factor in regional variation among wine grapes.

454 pyrosequencing analyses of bacterial and archaeal richness in 21 full-scale biogas digesters

Carina Sundberg, Waleed Abu Al‐Soud, Madeleine Larsson +5 more · FEMS Microbiology Ecology · 2013 · 729 citations

The microbial community of 21 full-scale biogas reactors was examined using 454 pyrosequencing of 16S rRNA gene sequences. These reactors included seven (six mesophilic and one thermophilic) digesting sewage sludge (SS) and 14 (ten mesophilic and four thermophilic) codigesting (CD) various combinations of wastes from slaughterhouses, restaurants, households, etc. The pyrosequencing generated more than 160,000 sequences representing 11 phyla, 23 classes, and 95 genera of Bacteria and Archaea. The bacterial community was always both more abundant and more diverse than the archaeal community. At the phylum level, the foremost populations in the SS reactors included Actinobacteria, Proteobacteria, Chloroflexi, Spirochetes, and Euryarchaeota, while Firmicutes was the most prevalent in the CD reactors. The main bacterial class in all reactors was Clostridia. Acetoclastic methanogens were detected in the SS, but not in the CD reactors. Their absence suggests that methane formation from acetate takes place mainly via syntrophic acetate oxidation in the CD reactors. A principal component analysis of the communities at genus level revealed three clusters: SS reactors, mesophilic CD reactors (including one thermophilic CD and one SS), and thermophilic CD reactors. Thus, the microbial composition was mainly governed by the substrate differences and the process temperature.

Fermentation of Cereals and Legumes: Impact on Nutritional Constituents and Nutrient Bioavailability

Janet Adeyinka Adebo, Patrick Berka Njobeh, Sefater Gbashi +4 more · Fermentation · 2022 · 235 citations

Fermented food products, especially those derived from cereals and legumes are important contributors to diet diversity globally. These food items are vital to food security and significantly contribute to nutrition. Fermentation is a process that desirably modifies food constituents by increasing the palatability, organoleptic properties, bioavailability and alters nutritional constituents. This review focuses on deciphering possible mechanisms involved in the modification of nutritional constituents as well as nutrient bioavailability during the fermentation of cereals and legumes, especially those commonly consumed in developing countries. Although modifications in these constituents are dependent on inherent and available nutrients in the starting raw material, it was generally observed that fermentation increased these nutritive qualities (protein, amino acids, vitamins, fats, fatty acids, etc.) in cereals and legumes, while in a few instances, a reduction in these constituents was noted. A general reduction trend in antinutritional factors was also observed with a corresponding increase in the nutrient bioavailability and bioaccessibility. Notable mechanisms of modification include transamination or the synthesis of new compounds during the fermentation process, use of nutrients as energy sources, as well as the metabolic activity of microorganisms leading to a degradation or increase in the level of some constituents. A number of fermented products are yet to be studied and fully understood. Further research into these food products using both conventional and modern techniques are still required to provide insights into these important food groups, as well as for an overall improved food quality, enhanced nutrition and health, as well as other associated socioeconomic benefits.

Substitution of fishmeal: Highlights of potential plant protein sources for aquaculture sustainability

Syed Makhdoom Hussain, Aumme Adeeba Bano, Shafaqat Ali +8 more · Heliyon · 2024 · 144 citations

High protein content, excellent amino acid profile, absence of anti-nutritional factors (ANFs), high digestibility and good palatability of fishmeal (FM), make it a major source of protein in aquaculture. Naturally derived FM is at risk due to an increase in its demand, unsustainable practices, and price. Thus, there is an urgent need to find affordable and suitable protein sources to replace FM. Plant protein sources are suitable due to their widespread availability and low cost. However, they contained certain ANFs, deficiency of some amino acids, low nutrient bioavailability and poor digestibility due to presence of starch and fiber. These unfavourable characteristics make them less suitable for feed as compared to FM. Thus, these potential challenges and limitations associated with various plant proteins have to be overcome by using different methods, i.e. enzymatic pretreatments, solvent extraction, heat treatments and fermentation, that are discussed briefly in this review. This review assessed the impacts of plant products on growth performance, body composition, flesh quality, changes in metabolic activities and immune response of fishes. To minimize the negative effects and to enhance nutritional value of plant products, beneficial functional additives such as citric acid, phytase and probiotics could be incorporated into the plant-based FM. Interestingly, these additives improve growth of fishes by increasing digestibility and nutrient utilization of plant based feeds. Overall, this review demonstrated that the substitution of fishmeal by plant protein sources is a plausible, technically-viable and practical option for sustainable aquaculture feed production.

Predicting and improving complex beer flavor through machine learning

Michiel Schreurs, Supinya Piampongsant, Miguel Roncoroni +10 more · Nature Communications · 2024 · 131 citations

The perception and appreciation of food flavor depends on many interacting chemical compounds and external factors, and therefore proves challenging to understand and predict. Here, we combine extensive chemical and sensory analyses of 250 different beers to train machine learning models that allow predicting flavor and consumer appreciation. For each beer, we measure over 200 chemical properties, perform quantitative descriptive sensory analysis with a trained tasting panel and map data from over 180,000 consumer reviews to train 10 different machine learning models. The best-performing algorithm, Gradient Boosting, yields models that significantly outperform predictions based on conventional statistics and accurately predict complex food features and consumer appreciation from chemical profiles. Model dissection allows identifying specific and unexpected compounds as drivers of beer flavor and appreciation. Adding these compounds results in variants of commercial alcoholic and non-alcoholic beers with improved consumer appreciation. Together, our study reveals how big data and machine learning uncover complex links between food chemistry, flavor and consumer perception, and lays the foundation to develop novel, tailored foods with superior flavors.

Millets: a solution to agrarian and nutritional challenges

Ashwani Kumar, Vidisha Tomer, Amarjeet Kaur +2 more · Agriculture & Food Security · 2018 · 382 citations

World is facing agrarian as well as nutritional challenges. Agricultural lands with irrigation facilities have been exploited to maximum, and hence we need to focus on dry lands to further increase grain production. Owing to low fertility, utilization of dry lands to produce sufficient quality grains is a big challenge. Millets as climate change compliant crops score highly over other grains like wheat and rice in terms of marginal growing conditions and high nutritional value. These nutri-cereals abode vitamins, minerals, essential fatty acids, phyto-chemicals and antioxidants that can help to eradicate the plethora of nutritional deficiency diseases. Millets cultivation can keep dry lands productive and ensure future food and nutritional security.

Microbial Cellulases and Their Industrial Applications

Ramesh Chander Kuhad, Rishi Gupta, Ajay Veer Singh · Enzyme Research · 2011 · 941 citations

Microbial cellulases have shown their potential application in various industries including pulp and paper, textile, laundry, biofuel production, food and feed industry, brewing, and agriculture. Due to the complexity of enzyme system and immense industrial potential, cellulases have been a potential candidate for research by both the academic and industrial research groups. Nowadays, significant attentions have been devoted to the current knowledge of cellulase production and the challenges in cellulase research especially in the direction of improving the process economics of various industries. Scientific and technological developments and the future prospects for application of cellulases in different industries are discussed in this paper.

General calibration of microbial growth in microplate readers

Keiran Stevenson, Alexander McVey, Ivan Clark +2 more · Scientific Reports · 2016 · 364 citations

Optical density (OD) measurements of microbial growth are one of the most common techniques used in microbiology, with applications ranging from studies of antibiotic efficacy to investigations of growth under different nutritional or stress environments, to characterization of different mutant strains, including those harbouring synthetic circuits. OD measurements are performed under the assumption that the OD value obtained is proportional to the cell number, i.e. the concentration of the sample. However, the assumption holds true in a limited range of conditions, and calibration techniques that determine that range are currently missing. Here we present a set of calibration procedures and considerations that are necessary to successfully estimate the cell concentration from OD measurements.

Influence of culture media, pH and temperature on growth and bacteriocin production of bacteriocinogenic lactic acid bacteria

En Yang, Lihua Fan, Jinping Yan +4 more · AMB Express · 2018 · 303 citations

There has been continued interest in bacteriocins research from an applied perspective as bacteriocins have potential to be used as natural preservative. Four bacteriocinogenic lactic acid bacteria (LAB) strains of Lactobacillus curvatus (Arla-10), Enterococcus faecium (JFR-1), Lactobacillus paracasei subsp. paracasei (JFR-5) and Streptococcus thermophilus (TSB-8) were previously isolated and identified in our lab. The objective of this study was to determine the optimal growth conditions for both LAB growth and bacteriocins production. In this study, various growth conditions including culture media (MRS and BHI), initial pH of culture media (4.5, 5.5, 6.2, 7.4 and 8.5), and incubation temperatures (20, 37 and 44 °C) were investigated for LAB growth measured as optical density (OD), bacteriocin activity determined as arbitrary unit and viability of LAB expressed as log CFU ml−1. Growth curves of the bacteriocinogenic LAB were generated using a Bioscreen C. Our results indicated that Arla-10, JFR-1, and JFR-5 strains grew well on both MRS and BHI media at growth temperature tested whereas TSB-8 strain, unable to grow at 20 °C. LAB growth was significantly affected by the initial pH of culture media (p < 0.001) and the optimal pH was found ranging from 6.2 to 8.5. Bacteriocin activity was significantly different in MRS versus BHI (p < 0.001), and the optimal condition for LAB to produce bacteriocins was determined in MRS broth, pH 6.2 at 37 °C. This study provides useful information on potential application of bacteriocinogenic LAB in food fermentation processes.

Functional Benefits of (Modest) Alcohol Consumption

Robin Dunbar, Jacques Launay, Rafael Wlodarski +4 more · Adaptive Human Behavior and Physiology · 2016 · 116 citations

Alcohol use has a long and ubiquitous history. Despite considerable research on the misuse of alcohol, no one has ever asked why it might have become universally adopted, although the conventional view assumes that its only benefit is hedonic. In contrast, we suggest that alcohol consumption was adopted because it has social benefits that relate both to health and social bonding. We combine data from a national survey with data from more detailed behavioural and observational studies to show that social drinkers have more friends on whom they can depend for emotional and other support, and feel more engaged with, and trusting of, their local community. Alcohol is known to trigger the endorphin system, and the social consumption of alcohol may thus have the same effect as the many other social activities such as laughter, singing and dancing that we use as a means of servicing and reinforcing social bonds.

Identifying and Estimating Ultraprocessed Food Intake in the US NHANES According to the Nova Classification System of Food Processing

Eurídice Martínez Steele, Lauren E O’Connor, Filippa Juul +5 more · Journal of Nutrition · 2022 · 129 citations

Non-Alcoholic and Craft Beer Production and Challenges

Liana Claudia Salanță, Teodora Emilia Coldea, Maria Valentina Ignat +6 more · Processes · 2020 · 154 citations

Beer is the most consumed alcoholic beverage in the world and the third most popular beverage after water and tea. Emerging health-oriented lifestyle trends, demographics, stricter legislation, religious prohibitions, and consumers’ preferences have led to a strong and steady growth of interest for non-alcoholic beers (NABs), low-alcohol beers (LABs), as well for craft beers (CBs). Conventional beer, as the worlds most consumed alcoholic beverage, recently gained more recognition also due to its potential functionality associated with the high content of phenolic antioxidants and low ethanol content. The increasing attention of consumers to health-issues linked to alcohol abuse urges breweries to expand the assortment of conventional beers through novel drinks concepts. The production of these beers employs several techniques that vary in performance, efficiency, and usability. Involved production technologies have been reviewed and evaluated in this paper in terms of efficiency and production costs, given the possibility that craft brewers might want to adapt them and finally introduce novel non-alcoholic drinks in the market.

Sensory Improvement of a Pea Protein-Based Product Using Microbial Co-Cultures of Lactic Acid Bacteria and Yeasts

Cynthia El Youssef, Pascal Bonnarme, Sébastien Fraud +3 more · Foods · 2020 · 151 citations

Consumer demands for plant-based products have increased in recent years. However, their consumption is still limited due to the presence of off-flavor compounds, primarily beany and green notes, which are mainly associated with the presence of aldehydes, ketones, furans, and alcohols. To overcome this problem, fermentation is used as a lever to reduce off-flavors. A starter culture of lactic acid bacteria (LAB) was tested in a 4% pea protein solution with one of the following yeasts: Kluyveromyces lactis, Kluyveromyces marxianus, or Torulaspora delbrueckii. The fermented samples were evaluated by a sensory panel. Non-fermented and fermented matrices were analyzed by gas chromatography coupled with mass spectrometry to identify and quantify the volatile compounds. The sensory evaluation showed a significant reduction in the green/leguminous attributes of pea proteins and the generation of new descriptors in the presence of yeasts. Compared to the non-fermented matrix, fermentations with LAB or LAB and yeasts led to the degradation of many off-flavor compounds. Moreover, the presence of yeasts triggered the generation of esters. Thus, fermentation by a co-culture of LAB and yeasts can be used as a powerful tool for the improvement of the sensory perception of a pea protein-based product.

The Role and Use of Non-Saccharomyces Yeasts in Wine Production

N.P. Jolly, O.P.H. Augustyn, Isak S. Pretorius · South African Journal of Enology and Viticulture · 2017 · 350 citations

The contribution by the numerous grape-must-associated non-Saccharomyces yeasts to wine fermentation has beendebated extensively. These yeasts, naturally present in all wine fermentations, are metabolically active and theirmetabolites can impact on wine quality. Although often seen as a source of microbial spoilage, there is substantialcontrary evidence pointing to a positive contribution by these yeasts. The role of non-Saccharomyces yeasts in winefermentation is therefore receiving increasing attention by wine microbiologists in Old and New World wineproducing countries. Species that have been investigated for wine production thus far include those from theCandida, Kloeckera, Hanseniaspora, Zygosaccharomyces, Schizosaccharomyces, Torulaspora, Brettanomyces,Saccharomycodes, Pichia and Williopsis genera. In this review the use and role of non-Saccharomyces yeast in wineproduction is presented and research trends are discussed.

Health benefits of whole grain: effects on dietary carbohydrate quality, the gut microbiome, and consequences of processing

Chris J. Seal, Christophe M. Courtin, Koen Venema +1 more · Comprehensive Reviews in Food Science and Food Safety · 2021 · 180 citations

Grains are important sources of carbohydrates in global dietary patterns. The majority of these carbohydrates, especially in refined-grain products, are digestible. Most carbohydrate digestion takes place in the small intestine where monosaccharides (predominantly glucose) are absorbed, delivering energy to the body. However, a considerable part of the carbohydrates, especially in whole grains, is indigestible dietary fibers. These impact gut motility and transit and are useful substrates for the gut microbiota affecting its composition and quality. For the most part, the profile of digestible and indigestible carbohydrates and their complexity determine the nutritional quality of carbohydrates. Whole grains are more complex than refined grains and are promoted as part of a healthy and sustainable diet mainly because the contribution of indigestible carbohydrates, and their co-passenger nutrients, is significantly higher. Higher consumption of whole grain is recommended because it is associated with lower incidence of, and mortality from, CVD, type 2 diabetes, and some cancers. This may be due in part to effects on the gut microbiota. Although processing of cereals during milling and food manufacturing is necessary to make them edible, it also offers the opportunity to still further improve the nutritional quality of whole-grain flours and foods made from them. Changing the composition and availability of grain carbohydrates and phytochemicals during processing may positively affect the gut microbiota and improve health.

Laccase: Microbial Sources, Production, Purification, and Potential Biotechnological Applications

Shraddha Shraddha, Ravi Shekher, Simran Sehgal +2 more · Enzyme Research · 2011 · 443 citations

Laccase belongs to the blue multicopper oxidases and participates in cross-linking of monomers, degradation of polymers, and ring cleavage of aromatic compounds. It is widely distributed in higher plants and fungi. It is present in Ascomycetes, Deuteromycetes and Basidiomycetes and abundant in lignin-degrading white-rot fungi. It is also used in the synthesis of organic substance, where typical substrates are amines and phenols, the reaction products are dimers and oligomers derived from the coupling of reactive radical intermediates. In the recent years, these enzymes have gained application in the field of textile, pulp and paper, and food industry. Recently, it is also used in the design of biosensors, biofuel cells, as a medical diagnostics tool and bioremediation agent to clean up herbicides, pesticides and certain explosives in soil. Laccases have received attention of researchers in the last few decades due to their ability to oxidize both phenolic and nonphenolic lignin-related compounds as well as highly recalcitrant environmental pollutants. It has been identified as the principal enzyme associated with cuticular hardening in insects. Two main forms have been found: laccase-1 and laccase-2. This paper reviews the occurrence, mode of action, general properties, production, applications, and immobilization of laccases within different industrial fields.

Production of Bacterial Cellulose by Gluconacetobacter hansenii Using Corn Steep Liquor As Nutrient Sources

Andréa Fernanda de Santana Costa, F. C. G. Almeida, Glória Maria Vinhas +1 more · Frontiers in Microbiology · 2017 · 339 citations

Cellulose is mainly produced by plants, although many bacteria, especially those belonging to the genus Gluconacetobacter, produce a peculiar form of cellulose with mechanical and structural properties that can be exploited in numerous applications. However, the production cost of bacterial cellulose (BC) is very high to the use of expensive culture media, poor yields, downstream processing, and operating costs. Thus, the purpose of this work was to evaluate the use of industrial residues as nutrients for the production of BC by Gluconacetobacter hansenii UCP1619. BC pellicles were synthesised using the Hestrin-Schramm (HS) medium and alternative media formulated with different carbon (sugarcane molasses and acetylated glucose) and nitrogen sources (yeast extract, peptone and corn steep liquor (CSL)). A jeans laundry was also tested. None of the tested sources (beside CSL) worked as carbon and nutrient substitute. The alternative medium formulated with 1.5% glucose and 2.5% CSL led to the highest yield in terms of dry and hydrated mass. The BC mass produced in the alternative culture medium corresponded to 73% of that achieved with the HS culture medium. The pellicles demonstrated a high concentration of microfibrils and nanofibrils forming a homogenous, compact, three-dimensional structure. The biopolymer produced in the alternative medium had greater thermal stability, as degradation began at 240°C, while degradation of the biopolymer produced in the HS medium began at 195°C. Both biopolymers exhibited high crystallinity. The mechanical tensile test revealed the maximum breaking strength and the elongation of the break of hydrated and dry pellicles. The dry BC film supported up to 48 MPa of the breaking strength and exhibited greater than 96.98% stiffness in comparison to the hydrated film. The dry film supported up to 48 MPa of the breaking strength and exhibited greater than 96.98% stiffness in comparison to the hydrated film. The values obtained for the Young's modulus in the mechanical tests in the hydrated samples indicated low values for the variable rigidity. The presence of water in the interior and between the nanofibers of the hydrated BC only favored the results for the elasticity, which was 56.37% higher when compared to the dry biomaterial.

Processing, nutritional composition and health benefits of finger millet in sub-saharan Africa

Shonisani Eugenia Ramashia, Tonna A. Anyasi, Eastonce Tend GWATA +2 more · Food Science and Technology · 2019 · 147 citations

Finger millet (Eleusine coracana) also known as tamba, is a staple cereal grain in some parts of the world with low income population. The grain is characterized by variations in colour (brown, white and light brown cultivars); high concentration of carbohydrates, dietary fibre, phytochemicals and essential amino acids; presence of essential minerals; as well as a gluten-free status. Finger millet (FM) in terms of nutritional composition, ranks higher than other cereal grains, though the grain is extremely neglected and widely underutilized. Nutritional configuration of FM contributes to reduced risk of diabetes mellitus, high blood pressure and gastro-intestinal tract disorder when absorbed in the body. Utilization of the grain therefore involves traditional and other processing methods such as soaking, malting, cooking, fermentation, popping and radiation. These processes are utilised to improve the dietetic and sensory properties of FM and equally assist in the reduction of anti-nutritional and inhibitory activities of phenols, phytic acids and tannins. However, with little research and innovation on FM as compared to conventional cereals, there is the need for further studies on processing methods, nutritional composition, health benefits and valorization with a view to commercialization of FM grains.

From stale bread and brewers spent grain to a new food source using edible filamentous fungi

Rebecca Gmoser, Rikard Fristedt, Karin Larsson +3 more · Bioengineered · 2020 · 129 citations

By-products from the food sector with a high load of organic matter present both a wastehandling problem related to expenses and to the environment, yet also an opportunity. This study aims to increase the value of stale bread and brewers spent grain (BSG) by re-introducing these residues to the food production chain by converting them to new protein-enriched products using the edible filamentous fungi Neurospora intermedia and Rhizopusoryzae. After 6 days of solid state fermentation (at 35C, with a95% relative humidity and moisture content of 40% in the substrate) on stale bread, a nutrient-rich fungal-fermented product was produced. The total protein content, as analyzed by total amino acids, increased from 16.5% in stale sourdough bread to 21.1% (on dry weight basis) in the final product with an improved relative ratio of essential amino acids. An increase in dietary fiber, minerals (Cu, Fe, Zn) and vitamin E, as well as an addition of vitamin D2 (0.89 g/g dry weight sample) was obtained compared with untreated stale bread. Furthermore, addition of BSG to the sourdough bread with the aim to improve textural changes after fermentation showed promising outcomes. Cultivation of N. intermedia or R. oryzae on stale sourdough bread mixed with 6.5% or 11.8% BSG, respectively, resulted in fungal-fermented products with similar textural properties to a commercial soybean burger. Bioconversion of stale bread and BSG by fungal solid state fermentation to produce a nutrientenriched food product was confirmed to be a successful way to minimize food waste and protein shortage.

Saccharomyces cerevisiae in the Production of Fermented Beverages

Graeme M. Walker, Graham G. Stewart · Beverages · 2016 · 441 citations

Alcoholic beverages are produced following the fermentation of sugars by yeasts, mainly (but not exclusively) strains of the species, Saccharomyces cerevisiae. The sugary starting materials may emanate from cereal starches (which require enzymatic pre-hydrolysis) in the case of beers and whiskies, sucrose-rich plants (molasses or sugar juice from sugarcane) in the case of rums, or from fruits (which do not require pre-hydrolysis) in the case of wines and brandies. In the presence of sugars, together with other essential nutrients such as amino acids, minerals and vitamins, S. cerevisiae will conduct fermentative metabolism to ethanol and carbon dioxide (as the primary fermentation metabolites) as the cells strive to make energy and regenerate the coenzyme NAD+ under anaerobic conditions. Yeasts will also produce numerous secondary metabolites which act as important beverage flavour congeners, including higher alcohols, esters, carbonyls and sulphur compounds. These are very important in dictating the final flavour and aroma characteristics of beverages such as beer and wine, but also in distilled beverages such as whisky, rum and brandy. Therefore, yeasts are of vital importance in providing the alcohol content and the sensory profiles of such beverages. This Introductory Chapter reviews, in general, the growth, physiology and metabolism of S. cerevisiae in alcoholic beverage fermentations.

Current Trends in Kombucha: Marketing Perspectives and the Need for Improved Sensory Research

Ju-Young Kim, Koushik Adhikari · Beverages · 2020 · 222 citations

Kombucha is a fermented functional beverage that started as a homemade beverage and grew into a commercial product in the U.S. by the turn of this century. The number of companies producing kombucha, as well as the variety of kombucha products, is increasing rapidly. The scientific research on kombucha also got active along with the growth in the market. The topics of kombucha research can be grouped into the substrate used in fermentation, the microbial composition of the cultures, processing methods, chemical composition, the health benefits and health risks associated with consumption, the utilization of symbiotic cultures of bacteria and yeasts (SCOBYs), etc. There are several already published in-depth scientific reviews covering these topics. Even with the sensory characteristics of kombucha being a critical aspect of the beverage, there are not many publications covering the sensory and consumer research on this beverage. This review paper aims to provide the current market status of kombucha and to show a need for scientific sensory and consumer research studies to help the kombucha researchers and industry working on this fast-growing beverage.

Yeast and bacterial modulation of wine aroma and flavour

Jan H. Swiegers, Eveline Bartowsky, Paul A. Henschke +1 more · Australian Journal of Grape and Wine Research · 2005 · 1,158 citations

Wine is a highly complex mixture of compounds which largely define its appearance, aroma, flavour and mouth-feel properties. The compounds responsible for those attributes have been derived in turn from three major sources, viz. grapes, microbes and, when used, wood (most commonly, oak). The grape-derived compounds provide varietal distinction in addition to giving wine its basic structure. Thus, the floral monoterpenes largely define Muscat-related wines and the fruity volatile thiols define Sauvignon-related wines; the grape acids and tannins, together with alcohol, contribute the palate and mouth-feel properties. Yeast fermentation of sugars not only produces ethanol and carbon dioxide but a range of minor but sensorially important volatile metabolites which gives wine its vinous character. These volatile metabolites, which comprise esters, higher alcohols, carbonyls, volatile fatty acids and sulfur compounds, are derived from sugar and amino acid metabolism. The malolactic fermentation, when needed, not only provides deacidification, but can enhance the flavour profile. The aroma and flavour profile of wine is the result of an almost infinite number of variations in production, whether in the vineyard or the winery. In addition to the obvious, such as the grapes selected, the winemaker employs a variety of techniques and tools to produce wines with specific flavour profiles. One of these tools is the choice of microorganism to conduct fermentation. During alcoholic fermentation, the wine yeast Saccharomyces cerevisiae brings forth the major changes between grape must and wine: modifying aroma, flavour, mouth-feel, colour and chemical complexity. The wine bacterium Oenococcus oeni adds its contribution to wines that undergo malolactic fermentation. Thus flavour-active yeasts and bacterial strains can produce desirable sensory results by helping to extract compounds from the solids in grape must, by modifying grape-derived molecules and by producing flavour-active metabolites. This article reviews some of the most important flavour compounds found in wine, and their microbiological origin.

Agro-industrial waste: a cost-effective and eco-friendly substrate to produce amylase

Bindu Naik, Vijay Kumar, Sheikh Rizwanuddin +5 more · Food Production Processing and Nutrition · 2023 · 65 citations

Abstract The increase in the global population has led to a substantial increase in the demand for food supply as well as food manufacturing industries that regularly produce large amounts of food waste. Agro-industrial waste has attracted tremendous attention all over the world since ancient times, such waste is usually dumped or burned and poses a threat to human health and the environment, which has always been a matter of serious concern. However, food waste is a major source of complex carbohydrates, proteins, lipids, vitamins, minerals, fibers, and helps in the manufacture of raw materials for a variety of industrial purposes such as the production of biofuels, enzymes, bioactive compounds, biodegradable plastics, surfactants. Hence it is necessary to convert food waste into value-added products that reduce environmental problems. The present review paper attempts to outline and analyze the potential of agro-industrial residues as cost-effective substrates to produce the enzyme amylase using a wide range of microbial strains. Graphical Abstract

The Microbial Diversity of Traditional Spontaneously Fermented Lambic Beer

Freek Spitaels, Anneleen D. Wieme, Maarten Janssens +5 more · PLoS ONE · 2014 · 261 citations

Lambic sour beers are the products of a spontaneous fermentation that lasts for one to three years before bottling. The present study determined the microbiota involved in the fermentation of lambic beers by sampling two fermentation batches during two years in the most traditional lambic brewery of Belgium, using culture-dependent and culture-independent methods. From 14 samples per fermentation, over 2000 bacterial and yeast isolates were obtained and identified. Although minor variations in the microbiota between casks and batches and a considerable species diversity were found, a characteristic microbial succession was identified. This succession started with a dominance of Enterobacteriaceae in the first month, which were replaced at 2 months by Pediococcus damnosus and Saccharomyces spp., the latter being replaced by Dekkera bruxellensis at 6 months fermentation duration.

Applications and Advances in Electronic-Nose Technologies

A. D. Wilson, Manuela Baietto · Sensors · 2009 · 1,099 citations

Electronic-nose devices have received considerable attention in the field of sensor technology during the past twenty years, largely due to the discovery of numerous applications derived from research in diverse fields of applied sciences. Recent applications of electronic nose technologies have come through advances in sensor design, material improvements, software innovations and progress in microcircuitry design and systems integration. The invention of many new e-nose sensor types and arrays, based on different detection principles and mechanisms, is closely correlated with the expansion of new applications. Electronic noses have provided a plethora of benefits to a variety of commercial industries, including the agricultural, biomedical, cosmetics, environmental, food, manufacturing, military, pharmaceutical, regulatory, and various scientific research fields. Advances have improved product attributes, uniformity, and consistency as a result of increases in quality control capabilities afforded by electronic-nose monitoring of all phases of industrial manufacturing processes. This paper is a review of the major electronic-nose technologies, developed since this specialized field was born and became prominent in the mid 1980s, and a summarization of some of the more important and useful applications that have been of greatest benefit to man.

Flavour-active volatile compounds in beer: production, regulation and control

Ademola O. Olaniran, Lettisha Hiralal, Mduduzi P. Mokoena +1 more · Journal of the Institute of Brewing · 2017 · 246 citations

Many classes of compounds have been shown to play an important role in the development of flavour characteristics of beer. This significantly influences its taste and sensory properties, thus affecting its market performance. Despite the intensive research aimed at unravelling the precise mechanism and regulation of flavour formation in beer, current knowledge remains far from complete. Several reviews are available on the general composition of beer and yeast metabolic pathways involved in the production of volatile compounds in beer. However, a limited amount of work has been reported concerning the influence of some of the beer constituents and other important parameters on beer flavour. This paper reviews the current knowledge of the biochemistry behind flavour formation in beer and discusses the different factors that influence its formation and how it can be controlled during brewery fermentation. Copyright © 2017 The Institute of Brewing & Distilling

Edible insects are the future?

A. van Huis · Proceedings of The Nutrition Society · 2016 · 352 citations

The global increase in demand for meat and the limited land area available prompt the search for alternative protein sources. Also the sustainability of meat production has been questioned. Edible insects as an alternative protein source for human food and animal feed are interesting in terms of low greenhouse gas emissions, high feed conversion efficiency, low land use, and their ability to transform low value organic side streams into high value protein products. More than 2000 insect species are eaten mainly in tropical regions. The role of edible insects in the livelihoods and nutrition of people in tropical countries is discussed, but this food source is threatened. In the Western world, there is an increasing interest in edible insects, and examples are given. Insects as feed, in particular as aquafeed, have a large potential. Edible insects have about the same protein content as conventional meat and more PUFA. They may also have some beneficial health effects. Edible insects need to be processed and turned into palatable dishes. Food safety may be affected by toxicity of insects, contamination with pathogens, spoilage during conservation and allergies. Consumer attitude is a major issue in the Western world and a number of strategies are proposed to encourage insect consumption. We discuss research pathways to make insects a viable sector in food and agriculture: an appropriate disciplinary focus, quantifying its importance, comparing its nutritional value to conventional protein sources, environmental benefits, safeguarding food safety, optimising farming, consumer acceptance and gastronomy.

Changes Occurring in Spontaneous Maize Fermentation: An Overview

Clemencia Chaves‐López, Chiara Rossi, Francesca Maggio +2 more · Fermentation · 2020 · 98 citations

Maize and its derived fermented products, as with other cereals, are fundamental for human nutrition in many countries of the world. Mixed cultures, principally constituted by lactic acid bacteria (LAB) and yeasts, are responsible for maize fermentation, thus increasing its nutritional value and extending the products’ shelf-life. Other microorganisms involved, such as molds, acetic acid bacteria, and Bacillus spp. can contribute to the final product characteristics. This review gives an overview of the impact of the activities of this complex microbiota on maize product development and attributes. In particular, starting from amylolytic activity, which is able to increase sugar availability and influence the microbial succession and production of exopolysaccharides, vitamins, and antimicrobial compounds, which improve the nutritional value. Further activities are also considered with positive effects on the safety profile, such as phytates detoxification and mycotoxins reduction.

Humulus lupulus L. as a Natural Source of Functional Biomolecules

Gonzalo Astray, Patricia Gullón, Beatriz Gullón +2 more · Applied Sciences · 2020 · 92 citations

Hops (Humulus lupulus L.) are used traditionally in the brewing industry to confer bitterness, aroma, and flavor to beer. However, in recent years, it has been reported that female inflorescences contain a huge variety of bioactive compounds. Due to the growing interest of the consumers by natural ingredients, intense research has been carried out in the last years to find new sources of functional molecules. This review collects the works about the bioactive potential of hops with applications in the food, pharmaceutical, or cosmetic industries. Moreover, an overview of the main extraction technologies to recover biomolecules from hops is shown. Bioactivities of hop extracts such as antibacterial, antifungal, cardioprotective, antioxidant, anti-inflammatory, anticarcinogenic, and antiviral are also summarized. It can be concluded that hops present a high potential of bioactive ingredients with high quality that can be used as preservative agents in fresh foods, extending their shelf life, and they can be incorporated in cosmetic formulation for skincare as well.

Microorganisms and food safety risks associated with indigenous fermented foods from Africa

Amarachukwu Anyogu, Ayomide Olukorede, Christian Anumudu +5 more · Food Control · 2021 · 83 citations

Diversity of the Neglected and Underutilized Crop Species of Importance in Benin

Alexandre Dansi, R. Vodouhè, Paulin Azokpota +6 more · The Scientific World JOURNAL · 2012 · 252 citations

Many of the plant species that are cultivated for food across the world are neglected and underutilized. To assess their diversity in Benin and identify the priority species and establish their research needs, a survey was conducted in 50 villages distributed throughout the country. The study revealed 41 neglected and underutilized crop species (NUCS) among which 19 were identified as of priority base on 10 criteria among which included their extent and degree of consumption. Reasons for neglect vary with the producers and the agricultural technicians. Market surveys revealed that NUCS are important source of household incomes and substantially contribute to poverty reduction. Review of the literature available revealed that most of the species are rich in nutrients and have some proven medicinal values and the promotion of their use would help in combating malnutrition and improving the health status of the local populations. The knowledge gaps and research needs are immense on most of the species identified as no concrete scientific data is nationally available. In terms of research, almost all has to be done starting from basic ethnobotanical investigation. The results will help the scientists and students willing to conduct research on NUCS in Benin to better orient their research programs.

Effect of Bacterial and Yeast Starters on the Formation of Volatile and Organic Acid Compounds in Coffee Beans and Selection of Flavors Markers Precursors During Wet Fermentation

Silvia Juliana Martinez, Ana Paula Pereira Bressani, Disney Ribeiro Dias +2 more · Frontiers in Microbiology · 2019 · 97 citations

Coffee quality has recently become a high demand of coffee consumers, due to all the specialty coffees available on the market. Specialty coffees can be generated by favoring growth of some groups of microorganisms during fermentation or by using starters. Just as yeast, a variety of bacteria can be used to generate important flavor precursors. The aim of this work was to test the efficiency of coffee sterilization and adhesion of microbial cells on beans, to evaluate the effect of yeast and bacterial starters on the production of organic and volatile compounds, and selection of potential flavor marker precursors during the wet fermentation. Three yeast and six bacterial starters were inoculated in coffee beans. Coffee sterilization and microbial adhesion was observed by scanning electron microscopy (SEM). Organic compounds were detected by high performance liquid chromatography (HPLC) and volatile compounds by gas chromatography–mass spectrometry (GC-MS). Micrographs from the SEM showed that sterilization took effect, because there were no microbial cells after autoclaving for 5 min. Also, it was observed an increase of microbial cells from 0h to 48 h of fermentation. Malic, lactic, and acetic acid were only detected in the bacterial treatments. Volatile compounds: 4-ethenyl-1,2-dimethoxybenzene, heptadecanol, 4-hydroxy-2-methylacetophenone, and 1-butanol,2-methyl were only found in yeast treatments. Guaiacol was only produced by the inoculated B. subtilis starters. In conclusion, yeast starters were better producers of volatile alcohols and bacterial starters of acid compounds. This study allowed the selection of potential flavor marker precursors, such as heptadecanol, 4-hydroxy-2-methylacetophenone, 7-methyl-4-octanol, and guaiacol.

Marination ingredients on meat quality and safety—a review

S. M. E. Rahman, Sharmeen Islam, Junyu Pan +7 more · Food Quality and Safety · 2023 · 49 citations

Abstract The practice of utilizing various categories of ingredients for marination has been prevalent in both home cooking and the meat industry for an extended period. Meat and meat products treated with various marination ingredients either alone or in combination with multiple marination processes can enhance color, flavor, and tenderness, while also improving their shelf life by reducing the growth of pathogenic microorganisms and lipid oxidation. This narrative review aims to examine all recent scientific literature on various meat and meat products subjected to marination. Through Google Scholar, PubMed, and Web of Science, the review summarizes all recent marinated and marination research articles, including types of marination ingredients, marination method, marinade mechanism, effect on sensory and nutritional quality, safety, shelf life, and health implications, resulting in a comprehensive overview of all information under marinades and marination for all scientists and food sectors concerned. The highlighted information will indicate future directions for the development of marination ingredients in the meat industry.

Antimicrobial and Probiotic Properties of Yeasts: From Fundamental to Novel Applications

Rima Hatoum, Steve Labrie, Ismaı̈l Fliss · Frontiers in Microbiology · 2012 · 328 citations

The yeasts constitute a large and heterogeneous group of microorganisms that are currently attracting increased attention from scientists and industry. Numerous and diverse biological activities make them promising candidates for a wide range of applications not limited to the food sector. In addition to their major contribution to flavor development in fermented foods, their antagonistic activities toward undesirable bacteria, and fungi are now widely known. These activities are associated with their competitiveness for nutrients, acidification of their growth medium, their tolerance of high concentrations of ethanol, and release of antimicrobial compounds such as antifungal killer toxins or "mycocins" and antibacterial compounds. While the design of foods containing probiotics (microorganisms that confer health benefits) has focused primarily on Lactobacillus and Bifidobacterium, the yeast Saccharomyces cerevisiae var. boulardii has long been known effective for treating gastroenteritis. In this review, the antimicrobial activities of yeasts are examined. Mechanisms underlying this antagonistic activity as well as recent applications of these biologically active yeasts in both the medical and veterinary sectors are described.

Integrating a Low-Cost Electronic Nose and Machine Learning Modelling to Assess Coffee Aroma Profile and Intensity

Claudia Gonzalez Viejo, Eden Tongson, Sigfredo Fuentes · Sensors · 2021 · 107 citations

Aroma is one of the main attributes that consumers consider when appreciating and selecting a coffee; hence it is considered an important quality trait. However, the most common methods to assess aroma are based on expensive equipment or human senses through sensory evaluation, which is time-consuming and requires highly trained assessors to avoid subjectivity. Therefore, this study aimed to estimate the coffee intensity and aromas using a low-cost and portable electronic nose (e-nose) and machine learning modeling. For this purpose, triplicates of nine commercial coffee samples with different intensity levels were used for this study. Two machine learning models were developed based on artificial neural networks using the data from the e-nose as inputs to (i) classify the samples into low, medium, and high-intensity (Model 1) and (ii) to predict the relative abundance of 45 different aromas (Model 2). Results showed that it is possible to estimate the intensity of coffees with high accuracy (98%; Model 1), as well as to predict the specific aromas obtaining a high correlation coefficient (R = 0.99), and no under- or over-fitting of the models were detected. The proposed contactless, nondestructive, rapid, reliable, and low-cost method showed to be effective in evaluating volatile compounds in coffee, which is a potential technique to be applied within all stages of the production process to detect any undesirable characteristics on-time and ensure high-quality products.

Loss of Heterozygosity Drives Adaptation in Hybrid Yeast

Caiti Smukowski Heil, Christopher DeSevo, Dave A. Pai +3 more · Molecular Biology and Evolution · 2017 · 153 citations

Hybridization is often considered maladaptive, but sometimes hybrids can invade new ecological niches and adapt to novel or stressful environments better than their parents. The genomic changes that occur following hybridization that facilitate genome resolution and/or adaptation are not well understood. Here, we examine hybrid genome evolution using experimental evolution of de novo interspecific hybrid yeast Saccharomyces cerevisiae × Saccharomyces uvarum and their parentals. We evolved these strains in nutrient-limited conditions for hundreds of generations and sequenced the resulting cultures identifying numerous point mutations, copy number changes, and loss of heterozygosity (LOH) events, including species-biased amplification of nutrient transporters. We focused on a particularly interesting example, in which we saw repeated LOH at the high-affinity phosphate transporter gene PHO84 in both intra- and interspecific hybrids. Using allele replacement methods, we tested the fitness of different alleles in hybrid and S. cerevisiae strain backgrounds and found that the LOH is indeed the result of selection on one allele over the other in both S. cerevisiae and the hybrids. This is an example where hybrid genome resolution is driven by positive selection on existing heterozygosity and demonstrates that even infrequent outcrossing may have lasting impacts on adaptation.

Beer Polyphenols—Bitterness, Astringency, and Off-Flavors

Kristina Habschied, Iztok Jože Košir, Vinko Krstanović +2 more · Beverages · 2021 · 76 citations

The acceptance of beer among consumers is most influenced by the taste and aroma. Polyphenols are widely responsible for both. Whereas polyphenols do not always result in a positive flavor and taste, they can surely impart certain off-flavors, which will be mentioned in this paper. However, the aftertaste is an important component of the beer-tasting experience and acceptance. The aftertaste, including astringency, may largely influence consumers’ consumption preference and behavior. Bitterness is one of the main, desirable characteristics of beer, but to an untrained consumer, it can often be mistaken with astringency. This review aims to describe the differences between these two properties. Both attributes derive from the same beer components, polyphenols from barley and hop, but there is a distinctive difference between them. To understand the complexity of bitterness and astringency, polyphenols behavior, characteristics, and stability during the brewing process are also described in this review.

Importance of lactic acid bacteria in Asian fermented foods

Sook Jong Rhee, Jang‐Eun Lee, Cherl‐Ho Lee · Microbial Cell Factories · 2011 · 335 citations

Lactic acid bacteria play important roles in various fermented foods in Asia. Besides being the main component in kimchi and other fermented foods, they are used to preserve edible food materials through fermentation of other raw-materials such as rice wine/beer, rice cakes, and fish by producing organic acids to control putrefactive microorganisms and pathogens. These bacteria also provide a selective environment favoring fermentative microorganisms and produce desirable flavors in various fermented foods. This paper discusses the role of lactic acid bacteria in various non-dairy fermented food products in Asia and their nutritional and physiological functions in the Asian diet.

Gluten-Free Brewing: Issues and Perspectives

Nazarena Cela, Nicola Condelli, Marisa Carmela Caruso +4 more · Fermentation · 2020 · 81 citations

Celiac disease (CD) is an immune-mediated gluten-sensitive enteropathy. Currently, it affects around 1% of world population, but it is constantly growing. Celiac patients have to follow a strict gluten-free (GF) diet. Beer is one of the most consumed beverages worldwide, but it is not safe for people with CD. It has a gluten content usually above the safe threshold (20 ppm), determined by the official method for hydrolyzed foods (R5-competitive-ELISA). The demand on the market for GF beers is increasingly growing. This review aims to provide a comprehensive overview of different strategies to produce GF beer, highlighting strengths and weaknesses of each approach and taking into account technological and sensory issues. GF cereals or pseudocereals have poor brewing attitudes (if used as main raw material) and give the beer unusual flavour. Instead, enzymatic treatments allow traditional brewing process followed by gluten content reduction. A survey on 185 GF-producing breweries (both industrial and craft) from all over the world have been considered to assess which approach is most used. Beers brewed with GF cereals and pseudocereals (used in well-balanced proportions) are more common than gluten-removed (GR) beers, obtained by enzymatic treatment.