Food Fermentation 2 Flashcards Preview

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Flashcards in Food Fermentation 2 Deck (17):
1

what are the two key biological molecules in fermentation?

Starch amylase
Cellulose NO B1-4 in humans.

2

Starch analysis method 1?

1. Enzyme methods use alpha-amylase and amyloglucosidase

3

Starch anaylsis method 2?

2. Acid hydrolysis
- non-specific
- GOPOD

4

Yeast fermentation aka brewing.. potable alcochol has three stages..what are they?

1. Conversion of biomass to fermentable sugars
a) Sugar crops (sugar cane- extraction of juice)
b) Starches (wheat, barley- enzyme hydrolysis)
c) Lignocellulose ( acid hydrolysis-milling)

5

2nd stage?

2. Fermentation
Predominately Saccharomyces spp. (yeast)
use glucose, fructose, galactose, maltose,

6

3rd stage?

Alcohol recovery/ product fermentation

7

Fermentation with oxygen and without oxygen

WITH oxygen: grows well, glucose--> CO2 and H2O
without O2--> Glucose~ 51% ethanol + CO2.
Side products are toxic. 5% glycerol, butyl alcohols and esters.
Flavors such as acetic and lactic acids.

8

Toxicty?

Ethanol can be. leaky at 4%, which can cause ethanol to go into cells. soluble metabolites ar elost.

9

Distillation of ethanol

1. Primary distillation--> beer wich is >85% (removes volitiles ether and aldehydes)
2. Rectification 96% ehtanol 3.5% water
3. dehydration benzene or cyclohexane 99.9%

10

What are the types of potable ethanol?

1. unforitified
2. Fortified
3. Distilled

11

Unforitifed what type of drinks

beers, wines

12

fortifeid

ports, sherry

13

distilled

Whiskey, gin, vodka, rum.

14

What is the difference between ales and lager beer?

ales beer is bottled for 3 weeks at 18-20C, while lager is bottled for 7 weeks at 13-17C bottom yeast

15

What is a cider?

yeast + Lactobacillus planetarium, L. mali. HOMOlactics
- fermented apple juice

16

What are wines?

fermented grape juice.
10-11% ethanol.
Ferment for 10 days, solids prepicipate for about 6 weeks, add acids. clear "must" for 6months to two years.

17

What is a difference if you dry the grapes in the sun?

Increase sugar content.