FND 100 Lecture Notes - Lecture 3: Malolactic Fermentation, Saccharomyces Cerevisiae, Ethanol Fermentation

• School: Ryerson University
• Department: Nutrition and Food
• Course: FND 100
• Professor: Yvonne Yuan

Document Summary

Wine production: fermented juice of fruit, usually grapes, apples berries, peaches, herbs. Inhibition of wild yeasts and other undesirable microbes: addition of 25-75mg/l so2, use of sulfites in wine production to decrease amount of wild yeast, the yeast brettanomyces contributes to distinct aromas, barnyard, horsey, leathery, phenolic. Bacteria are also involved in wine-making process: lactic acid bacteria are added in later stages of fermentation, 2o or malolactic fermentation: malic acid > lactic acid + co2, malolactic fermentation, diacetyl buttery flavor node in product. Bacterial fermentations: acetic acid bacteria (problem with storage of wine, acetobacter spp, produce acetic acid (vinegar) from fruit juices and alcohols, occurs in the presence of excess o2. Basic requirement is raw material that can undergo alcoholic fermentation: apples (apple cider), pears, grapes, honey, cerreals hydrolysed starches, beer, wine. C6h12o6 > 2c2h5oh + 2co2: bacteria (production of acetic acid)