Studied by 146 peopleExogenous electron acceptor (fermentation or respiration?)
Respiration
Pyruvate or derivative as electron acceptor (fermentation or respiration?)
Fermentation
Fermented foods
Chocolate, dairy products, meat products, vegetables and vegetable products, and yeast bread
Fermentation in food used for...
Food preservation
Fermentation in food may involve...
A succession of microbes
Fermentation in food is a ___ process
Self-limiting
Self-limiting process
Fermentation products inhibit fermenters
Fermentation in food changes ___ of the food
The flavor, odor, and texture
Dairy products are fermented using ___ bacteria
Lactic acid (LAB)
Characteristics of lactic acid bacteria
Acid-tolerant, aerotolerant, Gram-positive, non-spore forming, and strictly fermentative
Examples of lactic acid bacteria genus
Lactobacillus, lactococcus, leuconostoc, and streptococcus
Probiotics in yogurt are not necessarily...
The fermentative bacteria
Probiotics
Live microorganisms which, when administered in adequate amounts, confer a health benefit to the host
Sources of probiotics
Dietary supplements, fermented food, and non-oral supplements
Prebiotics
Substances (such as food) that promote the growth of probiotics
Probiotics must have ___ in order to survive inside one's body
Prebiotics
Can protect probiotics against stomach acid
Fat in yogurt
Pros of probiotics (5)
Considered safe for healthy individuals (nonpathogens), immunomodulation, improve general intestinal balance and health, improve oral health, and may lower blood pressure and serum cholesterol
How can probiotics improve general intestinal balance and health? (5)
Anticancer effects, colonization resistance, control of diarrhea, improve lactose intolerance, and treatment of enteric disease
Area of immunomodulation
Intestines
Cons of probiotics (3)
Difficult to accurately assess effectiveness, may cause mild side effects and systemic infection in severely immunocompromised individuals, and not regulated by FDA
Why is the effectiveness of probiotics difficult to accurately assess?
Each individual and each probiotic is different
How can the fact that probiotics are not regulated by the FDA be problematic?
Misleading advertising, most yogurts have relatively low CFU counts, and voluntary "Live Active Culture" seal
Voluntary "Live Active Culture" seal at time of...
Manufacture
Probiotics may becomes ___ in severely immunocompromised individuals
Opportunistic pathogens
Alcoholic beverages produced by...
Yeast from fermentation of sugar to CO2 and ethyl alcohol
Production of alcoholic beverages begins with...
Formation of liquid containing carbohydrates in readily fermentable form
Wine
Fermentation of grape juice
Beer
Fermentation of malted grain
Distilled beverages
Distillation of fermented solutions
Distilled beverages to make...
More concentrated alcohol
The science of wine production
Enology
Steps of wine production (4 - in order)
Must preparation, fermentation, aging, and racking
Steps of must preparation (2 - in order)
Grapes are crushed to yield must, must treated with sulfur dioxide fumigant, and Saccharomyces cerevisiae or S. elliposideus added
Types of wine fermentation
Primary and secondary
Primary wine fermentation
3-5 days at 20-28 degrees C
Secondary wine fermentation
1-3 weeks at ~20 degrees C
Secondary wine fermentation is also called...
Malolactic wine fermentation
Wine aging allows...
Bitter components to dissipate
Racking removes...
Sediment during fermentation
Alcohol content of wine
10-14%
How is sweet wine produced?
Fermentation is stopped before the fermentation of sugar can occur
How is sparkling wine produced?
CO2 byproduct is trapped
First two steps of ale and beer production (in order)
Mash and wort
Mashing
Process used to release fermentable sugars from grains
How to yield mash
Activation of enzymes and germination of grains to yield malt, and malt transferred to mash tun and mixed with water
Steps of wort production
Mash heated with hops in brew kettle and then hops are removed
Purpose of hops
Assist in clarification (i.e., serves as an antimicrobial) and provide flavor
Heating of mash to produce wort...
Inactivates hydrolytic enzymes
Wort
Clear liquid containing fermentable carbohydrates
Latter four steps of ale and beer production (in order)
Wort pitched, fermentation, storage, and bottling
Pitch
To inoculate wort with desired yeast
Types of yeasts used to pitch wort
Bottom yeast and top yeast
Bottom yeast
Sit on bottom and used in production of lager beers
Lagering
Storage (of ale and beer)
Top yeast
Float to top and used in production of ales
More CO2 (bottom yeast or top yeast?)
Top yeast
More foam (bottom yeast or top yeast?)
Top yeast
Higher pH (bottom yeast or top yeast?)
Bottom yeast
Fermentation of lager beer
7-12 days at 6-12 degrees C
Fermentation of ale
5-7 days at 14-23 degrees C
Usually added at bottling of ale and beer
CO2
How is CO2 added at bottling of ale and beer?
Using sugar
At bottling, beer can be...
Pasteurized or sterilized by filtration
Alcohol content of ale and beer
2-25%
Not supposed to be aged
Ale
Supposed to be consumed warm
Ale
Scotch
Whiskey made in Scotland
Bourbon
Whiskey made in Kentucky that is 25-50% corn
Extension of beer-making process
Whiskey
Distilled spirits
Liquor
Whiskey and bourbon begin with...
Sour mash
Sour mash (of whiskey and bourbon) is inoculated with...
Homolactic bacteria
Following fermentation, sour mash (of whiskey and bourbon) is...
Distilled to concentrate alcohol
Color of fresh distillate
Colorless
Color development of distillate occurs during...
Aging
Note
Flashcard