Effect of Sugars on Rate of Respiration of Baker's Yeast
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Brewing Yeast – Theory and Practice
Brewing yeast – theory and practice Chris Boulton Topics • What is brewing yeast? • Yeast properties, fermentation and beer flavour • Sources of yeast • Measuring yeast concentration The nature of yeast • Yeast are unicellular fungi • Characteristics of fungi: • Complex cells with internal organelles • Similar to plants but non-photosynthetic • Cannot utilise sun as source of energy so rely on chemicals for growth and energy Classification of yeast Kingdom Fungi Moulds Yeast Mushrooms / toadstools Genus > 500 yeast genera (Means “Sugar fungus”) Saccharomyces Species S. cerevisiae S. pastorianus (ale yeast) (lager yeast) Strains Many thousands! Biology of ale and lager yeasts • Two types indistinguishable by eye • Domesticated by man and not found in wild • Ale yeasts – Saccharomyces cerevisiae • Much older (millions of years) than lager strains in evolutionary terms • Lot of diversity in different strains • Lager strains – Saccharomyces pastorianus (previously S. carlsbergensis) • Comparatively young (probably < 500 years) • Hybrid strains of S. cerevisiae and wild yeast (S. bayanus) • Not a lot of diversity Characteristics of ale and lager yeasts Ale Lager • Often form top crops • Usually form bottom crops • Ferment at higher temperature o • Ferment well at low temperatures (18 - 22 C) (5 – 10oC) • Quicker fermentations (few days) • Slower fermentations (1 – 3 weeks) • Can grow up to 37oC • Cannot grow above 34oC • Fine well in beer • Do not fine well in beer • Cannot use sugar melibiose • Can use sugar melibiose Growth of yeast cells via budding + + + + Yeast cells • Each cell is ca 5 – 10 microns in diameter (1 micron = 1 millionth of a metre) • Cells multiply by budding a b c d h g f e Yeast and ageing - cells can only bud a certain number of times before death occurs. -
BREWERS' CRYSTALS® High Maltose Corn Syrup Solids
BREWERS’ CRYSTALS® High Maltose Corn Syrup Solids Advantages • Good match for all malt wort • Gluten free • Consistent purity and quality while adding flexibility and capacity Ingredion understands that brewery is an art as well as a science; our brewing adjunct portfolio is based on more What is it? than 100 years of service to the industry with a variety of ingredients. We take pride in our quality and ISO 9001 and BREWERS’ CRYSTALS High Maltose Corn Syrup Solids are FSSC 22000 systems certifications and our reliability one fermentable carbohydrates from corn, specially produced of the strongest supply chains in the industry. to obtain a profile close to an all-barley malt wort (Figure 1). Easy to use in powder form, they can be added directly to the brew kettle to create beers with crisper lighter flavor, or later How do I use it? in the process to add more complex character in priming. Ingredion BREWERS’ CRYSTALS HM Corn Syrup Solids can be easily added as an adjunct directly to the brewing kettle BREWERS’ CRYSTALS HM Corn Syrup Solids provide 100% or before filtration steps to add crisp and light character- total extract and 80% fermentable extract allowing the istics to lagers, ales and special beer recipes, or in priming Brew Master the flexibility of including them in a broad for added notes to complex beers. range of formulation and thus a wider spectrum of beers. Why should I use it? FIGURE 1: CARBOHYDRATE PROFILES COMPARISON 60 The benefits of BREWERS’ CRYSTALS HM Corn Syrup Solids: 56 • Packaged in convenient 25 kg (55 lb) multiwall poly-lined 52 BREWERS’ 50 CRYSTALS bags, they are easy to handle and store without the need for Wort* additional liquid handling systems. -
Alcoholic Fermentation Without Yeast Cells*
Reprinted from New Beer in an Old Bottle: Eduard Buchner and the Growth of Biochemical Knowledge, pp. 25–31, ed. A. Cornish-Bowden, Universitat de València, Spain, 1997 ALCOHOLIC FERMENTATION WITHOUT YEAST CELLS* Eduard Buchner Until now it has not been possible to separate fermenting activity from living yeast cells; the following describes a procedure that solves this problem. One thousand grams of brewer’s yeast1 that had been cleaned as a prerequisite for the preparation of compressed yeast, but to which no potato starch had been added, is carefully mixed with the same weight of quartz sand2 and 250 g Kieselguhr. It is then triturated until the mass has become moist and pliable. Now 100 g of water are added to the paste, it is wrapped in filter cloth and gradually subjected to a pressure of 400–500 atmospheres: 350 cc press juice are obtained. The residual cake is again triturated, sieved, and 100 g water are added. A further 150 cc of press juice result when the cake is again subjected to the same pressure in the hydraulic press. One kg of yeast hence yields 500 cc press juice, containing about 300 cc cell substances. Traces of turbidity are now removed by shaking the press juice with 4 g of Kieselguhr and filtering through paper with repeated refiltration of the first portions. The resulting press juice is a clear, slightly opalescent yellow liquid with a pleasant yeast odour. A single determination of the spe- cific gravity gave a value of 1.0416 (17°C). A large amount of coagu- lum separates upon boiling, so that the liquid almost completely *Preliminary Note, received 11 January. -
Multiple Genetic Origins of Saccharomyces Cerevisiae in Bakery
Multiple genetic origins of Saccharomyces cerevisiae in bakery Frédéric Bigey, Diego Segond, Lucie Huyghe, Nicolas Agier, Aurélie Bourgais, Anne Friedrich, Delphine Sicard To cite this version: Frédéric Bigey, Diego Segond, Lucie Huyghe, Nicolas Agier, Aurélie Bourgais, et al.. Multiple genetic origins of Saccharomyces cerevisiae in bakery. Comparative genomics of eukaryotic microbes: genomes in flux, and flux between genomes, Oct 2019, Sant Feliu de Guixol, Spain. hal-02950887 HAL Id: hal-02950887 https://hal.archives-ouvertes.fr/hal-02950887 Submitted on 28 Sep 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. genetic diversity of229 propagating a natural sourdough, which is a of mixed naturally fermented domestication of wide diversity of fermented products like wine, Saccharomyces cerevisiae sake, beer, cocoa and bread. While bread is of cultural and historical importance, the highly diverse environments like human, wine, sake, fruits, tree, soil... fruits, tree, human, wine, sake, like highly diverse environments clade on the 1002 genomes whichtree, also includes beer strains. Sourdough strains mosaic are and genetically are to related strains from strains. Selection for strains commercial has maintained autotetraploid. strains mostly to Commercial are related strains of origin the Mixed The origin of bakery strains is polyphyletic. -
Relation Between the Recipe of Yeast Dough Dishes and Their Glycaemic Indices and Loads
foods Article Relation between the Recipe of Yeast Dough Dishes and Their Glycaemic Indices and Loads Ewa Raczkowska * , Karolina Ło´zna , Maciej Bienkiewicz, Karolina Jurczok and Monika Bronkowska Department of Human Nutrition, Faculty of Biotechnology and Food Sciences, Wrocław University of Environmental and Life Sciences, 51-630 Wroclaw, Poland * Correspondence: [email protected]; Tel.: +48-71-320-7726 Received: 23 July 2019; Accepted: 30 August 2019; Published: 1 September 2019 Abstract: The aim of the study was to evaluate the glycaemic indices (GI) and glycaemic loads (GL) of four food dishes made from yeast dough (steamed dumplings served with yoghurt, apple pancakes sprinkled with sugar powder, rolls with cheese and waffles with sugar powder), based on their traditional and modified recipes. Modification of the yeast dough recipe consisted of replacing wheat flour (type 500) with whole-wheat flour (type 2000). Energy value and the composition of basic nutrients were assessed for every tested dish. The study was conducted on 50 people with an average age of 21.7 1.1 years, and an average body mass index of 21.2 2.0 kg/m2. The GI of the analysed ± ± food products depended on the total carbohydrate content, dietary fibre content, water content, and energy value. Modification of yeast food products by replacing wheat flour (type 500) with whole-wheat flour (type 2000) contributed to the reduction of their GI and GL values, respectively. Keywords: glycaemic index; glycaemic load; yeast dough 1. Introduction In connection with the growing number of lifestyle diseases, consumers pay increasing attention to food, not only to food that have a better taste but also to food that help maintain good health. -
Sensory Evaluation and Staling of Bread Produced by Mixed Starter of Saccharomyces Cerevisiae and L.Plantarum
J. Food and Dairy Sci., Mansoura Univ., Vol. 5 (4): 221 - 233, 2014 Sensory evaluation and staling of bread produced by mixed starter of saccharomyces cerevisiae and l.plantarum Swelim, M. A. / Fardous M. Bassouny / S. A. El-Sayed / Nahla M. M. Hassan / Manal S. Ibrahim. * Botany Department, Faculty of science, Banha University. ** Agricultural Microbiology Department, Agricultural Research Center, Giza, Egypt. ***Food Technology Research Institute, Agricultural Research Center, Giza, Egypt. ABSTRACT Impact of processed conditions and type of starter cultivars on characteristics of wheat dough bread by using mixed starter cultivars of Sacch. cerevisiae and L. plantarum was estimated. L. plantarum seemed to be more effective in combination with Sacch. cerevisiae on the dough volume. Dough produced by starter containing L. plantarum characterized with lower PH and higher total titratable acidity (TTA) and moisture content, in comparison with control treatment. Highly significant differences in aroma and crumb texture were recorded with bread produced by starter culture containing L. plantarum. The obtained results also revealed significant differences in bread firmness which reflected the staling and its rate among the tested treatments after 1, 3, 5 and 6 days during storage time at room temperature. Data also confirmed a processing technique using L. planturium mixed with Sacch.cerevisia to enhance organoleptic properties of produced bread. INTRODUCTION Cereal fermentation is one of the oldest biotechnological processes, dating back to ancient Egypt, where both beer and bread were produced by using yeasts and lactic acid bacteria (LAB), Clarke and Arendt, (2005). Starters composed of specific individual LAB, or mixed with yeasts, became available a few years ago allowing the production of a full sourdough in one- stage process. -
AP-42, CH 9.13.4: Yeast Production
9.13.4 Yeast Production 9.13.4.1 General1 Baker’s yeast is currently manufactured in the United States at 13 plants owned by 6 major companies. Two main types of baker’s yeast are produced, compressed (cream) yeast and dry yeast. The total U. S. production of baker’s yeast in 1989 was 223,500 megagrams (Mg) (245,000 tons). Of the total production, approximately 85 percent of the yeast is compressed (cream) yeast, and the remaining 15 percent is dry yeast. Compressed yeast is sold mainly to wholesale bakeries, and dry yeast is sold mainly to consumers for home baking needs. Compressed and dry yeasts are produced in a similar manner, but dry yeasts are developed from a different yeast strain and are dried after processing. Two types of dry yeast are produced, active dry yeast (ADY) and instant dry yeast (IDY). Instant dry yeast is produced from a faster-reacting yeast strain than that used for ADY. The main difference between ADY and IDY is that ADY has to be dissolved in warm water before usage, but IDY does not. 9.13.4.2 Process Description1 Figure 9.13.4-1 is a process flow diagram for the production of baker’s yeast. The first stage of yeast production consists of growing the yeast from the pure yeast culture in a series of fermentation vessels. The yeast is recovered from the final fermentor by using centrifugal action to concentrate the yeast solids. The yeast solids are subsequently filtered by a filter press or a rotary vacuum filter to concentrate the yeast further. -
The Relationship Between Fructose, Glucose and Maltose Content With
stry: Cu i rre em n t Moussa et al., Organic Chem Curr Res 2012, 1:5 h R C e c s i e n a DOI: 10.4172/2161-0401.1000111 a r Organic Chemistry c g r h O ISSN: 2161-0401 Current Research ResearchResearch Article Article OpenOpen Access Access The Relationship between Fructose, Glucose and Maltose Content with Diastase Number and Anti-Pseudomonal Activity of Natural Honey Combined with Potato Starch Ahmed Moussa1*, Djebli Noureddine2, Aissat Saad1 and Salima Douichene2 1Institute of Veterinary Sciences University Ibn-Khaldoun, Tiaret, Algeria 2Departments of Biology, Faculty of Sciences, Mostaganem University, Algeria Abstract Honey whose medicinal uses date from ancient times has been lately rediscovered as therapy for burns. Objective: To evaluate the additive action of potato starch on the antipseudomonal activity of natural honey. Methods: Physicochemical parameters of 6 samples of Algerian honeys were analysed; four parameters were measured, including Diastase, glucose, fructose and maltose. The antibacterial activity was tested using the well-agar diffusion assay. Results: Six honey samples with initial diastase activity between 22.1 and 7.3 Schade units were tested. Glucose, fructose and maltose values range between 21, 45-30, 95%, 25, 20-37, 81% and 4, 72-78, 45% respectively. The zone inhibition diameter (ZID) for the six honey samples without starch against P. aureogenosa ranged between 26 and 31 mm. When starch was mixed with honey and then added to well, a zone inhibition increase diameter (ZIID) 27 and 32 mm. The percentage increase (PI %) was noticed with each variety and it ranged between 3, 57 and 18, 75%. -
14419802.Pdf
View metadata, citation and similar papers at core.ac.uk brought to you by CORE REVIEW ARTICLE 277 Potential Application of Yeast β-Glucans in Food Industry Vesna ZECHNER-KRPAN 1 Vlatka PETRAVIĆ-TOMINAC 1 ( ) Ines PANJKOTA-KRBAVČIĆ 2 Slobodan GRBA 3 Katarina BERKOVIĆ 4 Summary Diff erent β-glucans are found in a variety of natural sources such as bacteria, yeast, algae, mushrooms, barley and oat. Th ey have potential use in medicine and pharmacy, food, cosmetic and chemical industries, in veterinary medicine and feed production. Th e use of diff erent β-glucans in food industry and their main characteristics important for food production are described in this paper. Th is review focuses on benefi cial properties and application of β-glucans isolated from diff erent yeasts, especially those that are considered as waste from brewing industry. Spent brewer’s yeast, a by-product of beer production, could be used as a raw-material for isolation of β-glucan. In spite of the fact that large quantities of brewer’s yeast are used as a feedstuff , certain quantities are still treated as a liquid waste. β-Glucan is one of the compounds that can achieve a greater commercial value than the brewer’s yeast itself and maximize the total profi tability of the brewing process. β-Glucan isolated from spent brewer’s yeast possesses properties that are benefi cial for food production. Th erefore, the use of spent brewer’s yeast for isolation of β-glucan intended for food industry would represent a payable technological and economical choice for breweries. -
Invert Sugar Determination by Polarimeter
Invert Sugar Determination by Polarimeter Invert sugar (IS) contains fructose and glucose in roughly equal proportions. The Invert sugar is greater in demand than pure glucose as food and drink sweeteners, because fructose is sweeter than glu- cose. Main consumers of Invert Sugar are the baking, beverages, canning, confectionery and dairy industries. In addition, high fructose syrup is used in many other processed foods like jams and jellies. However, it is being used only in biscuits and soft drinks. A manufacturer of IS expecting to supply it in next couple of years to the confectionery, fruit canning, processed foods and dairy products industries also. Fructose, also known as fruit sugar, is the sweetest natural sugar and is found in fruits, vegeta- bles, and honey. The body responds to fructose in a different way than to glucose and sucrose. Fructose is more satiating, and it is up to 1.8 times sweeter than sucrose, making it useful in foods and bever- ages for the health conscious. Fructose is also ideal for use in diabetic foods as it has very little effect on blood glucose and only a negligible effect on the secretion of insulin. Enzymatic treat- ments are a now a major way of producing sweeteners, including syrups derived from sucrose derived from sucrose or starch th at contain mixtures of glucose, maltose, fructose, and other sugars. Glucose has 70-75% the sweetening strength of beet sugar (sucrose), but fructose is twice as sweet as sucrose. Thus, processes for the manufacture of fructose are of considerable value. Invertase enzyme is used traditionally in the production of inverted sugars for industry, espe- cially in the manufacture of candies and preserves, production of lactic acid and ethanol pro- duction from fermentation of cane sugar molasses. -
Impact of Wort Amino Acids on Beer Flavour: a Review
fermentation Review Impact of Wort Amino Acids on Beer Flavour: A Review Inês M. Ferreira and Luís F. Guido * LAQV/REQUIMTE, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto, Portugal; ines.fi[email protected] * Correspondence: [email protected]; Tel.: +351-220-402-644 Received: 3 March 2018; Accepted: 25 March 2018; Published: 28 March 2018 Abstract: The process by which beer is brewed has not changed significantly since its discovery thousands of years ago. Grain is malted, dried, crushed and mixed with hot water to produce wort. Yeast is added to the sweet, viscous wort, after which fermentation occurs. The biochemical events that occur during fermentation reflect the genotype of the yeast strain used, and its phenotypic expression is influenced by the composition of the wort and the conditions established in the fermenting vessel. Although wort is complex and not completely characterized, its content in amino acids indubitably affects the production of some minor metabolic products of fermentation which contribute to the flavour of beer. These metabolic products include higher alcohols, esters, carbonyls and sulfur-containing compounds. The formation of these products is comprehensively reviewed in this paper. Furthermore, the role of amino acids in the beer flavour, in particular their relationships with flavour active compounds, is discussed in light of recent data. Keywords: amino acids; beer; flavour; higher alcohols; esters; Vicinal Diketones (VDK); sulfur compounds 1. Introduction The process by which beer has been brewed has not changed significantly since its discovery over 2000 years ago. Although industrial equipment is used for modern commercial brewing, the principles are the same. -
Nutritive Sweeteners from Corn Have Become America’S Premier Sweeteners
NutritiveNutritive SweetenersSweeteners FromFrom CornCorn CONTENTS Member Companies and Plant Locations ....................................... 2 Foreword .......................................................................................... 3 Historical Perspective ...................................................................... 4 Research and development orientation ....................................... 5 Technology aimed at needs .......................................................... 7 Growth, Development and Diversity ............................................. 7 CONTENTS Classification and Nutrition ............................................................ 9 Classification ................................................................................. 9 Corn sweeteners in nutrition ..................................................... 10 Technical Background ................................................................... 11 Corn starch ................................................................................. 11 Starch hydrolysis ........................................................................ 13 Crystalline dextrose .................................................................... 14 Dextrose isomerization .............................................................. 15 Manufacture ................................................................................... 17 Corn syrups ................................................................................ 17 Dried corn syrups ......................................................................