Open Access Journal of Pharmaceutical Research ISSN: 2574-7797 MEDWIN PUBLISHERS Committed to Create Value for Researchers Yeast as Biotechnological Tool in Food Industry El-Ghwas DE1, Elkhateeb WA1*, Akram M2 and Daba GM1 Review Article 1Chemistry of Natural and Microbial Products Department, Pharmaceutical Industries Volume 5 Issue 3 Division, National Research Centre, Egypt Received Date: July 05, 2021 2Department of Eastern Medicine Government College University Faisalabad-Pakistan, Published Date: July 26, 2021 Pakistan DOI: 10.23880/oajpr-16000243 *Corresponding author: Waill A Elkhateeb, Chemistry of Natural and Microbial Products Department, Pharmaceutical Industries Division, National Research Centre, Dokki, Giza, 12622, Egypt, Tel: +201013241936; Fax: +20233370931; Email: [email protected] Abstract Yeasts are widely spread in nature. Fermentation of sugars by yeast is the oldest and largest application of this technology. Many types of yeasts are used for making many foods: baker’s yeast in bread production, brewer’s yeast in beer fermentation, and yeast in wine. This work describes the prevalence of yeasts in food products. Keywords: Yeast; Food processing; Industrial application; Sugar fermentation Introduction bakeries and breweries [7]. Yeasts are eukaryotic, single-celled microorganisms Yeasts are very common in the environment, and are often isolated from sugar-rich materials. Examples include yeast originated hundreds of millions of years ago, and at naturally occurring yeasts on the skins of fruits and berries leastclassified 1,500 as speciesmembers are ofcurrently the fungus recognized kingdom. [1-3]. The Theyfirst (such as grapes, apples, or peaches), and exudates from are estimated to constitute 1% of all described fungal plants (such as plant saps or cacti). Some yeast is found species [4]. Yeast sizes vary greatly, depending on species in association with soil and insects [8,9]. The ecological and environment, typically measuring 3–4 µm in diameter, function and biodiversity of yeasts are relatively unknown although some yeast can grow to 40 µm in size [5]. Most compared to those of other microorganisms [10]. Yeasts, yeasts reproduce asexually by mitosis, and many do so by the including Candida albicans, Rhodotorula rubra, Torulopsis asymmetric division process known as budding. With their and Trichosporon cutaneum, have been found living in single-celled growth habit, yeasts can be contrasted with molds, which grow hyphae. Fungal species that can take both forms (depending on temperature or other conditions) are andbetween even people’sdeep-sea toesenvironments as part of hosttheir an skin array flora of yeastsYeasts [11- are called dimorphic fungi. 14].also present in the gut flora of mammals and some insects The word “yeast” comes from Old English gist, gyst, and Even if bacteria represent the most studied targets in from the Indo-European root yes-, meaning “boil”, “foam”, or Food Microbiology (pathogens, starter cultures, probiotics, “bubble”[6]. Yeast microbes are probably one of the earliest domesticated organisms. Archaeologists digging in Egyptian date of birth of Food Microbiology as science is the mid of ruins found early grinding stones and baking chambers for 19thproduction century, of whenharmful Pasteur or positive studied compounds), alcoholic fermentation, the official yeast-raised bread, as well as drawings of 4,000-year-old a process executed by yeasts. Also, the useful physiological Yeast as Biotechnological Tool in Food Industry Pharm Res 2 Open Access Journal of Pharmaceutical Research secondary products. It is a complex process and yeasts are biotechnology. Many types of yeasts are used for making responsible for this conversion [25]. Fast fermentation manyproperties foods: of baker’syeast haveyeast led in tobread their production, use in the brewer’s field of of grape juice sugars to high ethanol concentrations is yeast in beer fermentation, and yeast in wine fermentation essential for wine yeasts. Wine yeasts should exhibit and for xylitol production [15]. Also, in industry, yeasts are uniform dispersion and produce minimal foam. At the end commercially used in the production of alcoholic beverages, of the fermentation, sediment should be quickly taken industrial alcohols, baker’s yeast, enzymes and yeast-derived from the wine. It is also important that the yeast should not give slow, sluggish or stuck fermentations [26]. Yeasts role in the spoilage of foods and beverages and some can beflavour pathogenic. products Of [16]. the Furthermore,yeasts, Saccharomyces yeasts play cerevisiae detrimental and related species are widely used in the food and beverage suchalso makeas esters, positive acids, contributions alcohols, aldehydes, to wine ketones, flavour polyols,by the industries. Many species of Saccharomyces are safe (GRAS) volatilesynthesis sulphur of other compounds minor metabolites which directly that define impact the the flavour, wine and the term “yeast” is generally employed as synonymous with Saccharomyces cerevisiae [17]. Therefore, this chapter Kloeckera spp. and Candida spp., dominate at the beginning offlavour the fermentation[27,28]. The andnon-Saccharomyces affect the characteristics yeasts, commonly of wine processing. [29]. The other isolated yeasts are Metschnikowia, Dekkera, will briefly discuss the beneficial aspects of yeasts in food Pichia, Kluyveromyces, Issatchenkia, Saccharomycodes, Baker’s Yeast Zygosaccharomyces, Torulaspora, Debaryomyces, and Schizosaccharomyces [29]. The characteristics of wine yeasts Baker’s yeast, Saccharomyces cerevisiae, is used for must include some properties such as rapid initiation of bakery and confectionary processes throughout the world [18]. Baker’s yeast can be found in different forms tolerance, high osmotolerance, moderate biomass, high like compressed, granular, cream, dried pellet, instant, geneticfermentation, stability, high high sulphitefermentation tolerance, effiiency, low sulphite high bindingethanol encapsulated or frozen [19]. One of the most desirable activity, low foam formation, compacts sediment, resistance characteristics of baker’s yeast strains is high fermentation to desiccation, killer activity, genetic marking, proteolytic rate because is priority desired for baker’s yeast strains since activity and low nitrogen demand. All these properties are it is completely connected to dough-leavening. Yeasts at the found in Saccharomyces cerevisiae [30]. same time encourage gluten network and generate aromatic compounds [20]. Also, rapidly utilization of maltose, tolerance Meat Fermented Food to high levels of sucrose, enduring freeze-thawing stress and resulting in production of high levels of CO2 therefore rising Yeasts are found on meat and processed meat products. dough volume. CO2 is soluble in water and saturates the They have also positive effects on fermented meat products aqueous phase. After reaching saturation, all CO2 produced and many yeast species such as Candida, Debaryomyces, passes through unsaturated gas phase and permit rising of Pichia, Trichosporon, Cryptococcus, Rhodotorula and Yarrowia the volume of bread. Solubilization of CO2 in water results have been isolated from fermented meat products, especially in decreasing the pH and elevates the acidity of the dough sausages [31,32]. Lipolytic and proteolytic activities, which [21]. In addition, CO2 affects rheological characteristics of fermented dough also producing aroma compounds [20,22]. those yeasts were described [33]. Most frequently isolated Aroma compounds are formed widely in the crumb of bread yeastscontribute are toYarrowia flavour lipolyticadue to the and production Debaryomyces of volatiles, hansenii of and the most abundant compounds are alcohols, aldehydes [34]. Debaryomyces hansenii is also used as commercial as well as 2,3-butanedione (diacetyl), 3-hydroxy-2-butanone starter culture in fermented meat products due to its positive (acetoin) and esters [23]. Another desired feature of baker’s yeast is using disaccharide melibiose. Baker’s yeast should be osmotolerant, able to tolerate chemicals (salt, propionates), contributionsDiary Fermented on final product Food [33]. maintain a high growth capacity, should not aggregate and must have a good storage capability. In addition, during the Yeasts such as Candidam lusitaniae, Candida krusei, Kluveromyces lactis, Debaryomyces hansenii, Yarrowia, dough making, the yeast must have a high rate of vitality [24]. lipolytica, Kluyveromyces marxianus, Saccharomyces drying process and after the addition of dry yeast to flour for cerevisiae, Galactomyces geotrichum, Candida zeylanoides and Wine’s Yeast various Pichia species play essential role due to their important functions in dairy-based products such as contributing to the Yeasts are important microorganisms in wine ripening of cheese, speeding up the maturation, improving microbiology. Saccharomyces able to make biotransformation texture and aroma characteristics of certain milk products, of grape sugars into ethanol, carbon dioxide and several increasing pH of cheese, manufacturing of some metabolites Elkhateeb WA, et al. Yeast as Biotechnological Tool in Food Industry. Pharm Res 2021, 5(3): 000243. Copyright© Elkhateeb WA, et al. 3 Open Access Journal of Pharmaceutical Research like ethanol, acetaldehyde, CO2, amino acids and vitamins, nowadays used for some specialty beers. Traditional ciders removing toxic end-products of metabolism, taking part in are produced from spontaneous fermentation of juice some interactions