Term
| How are milk proteins denatured? |
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Definition
| They are denatured by the acids produced during microbial fermentative metabolism |
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Term
| The two major bacteria in the starter culture of yogurt |
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Definition
| Streptococcus thermophilus (responsible for acid) and lactobacillus bulgaricus (responsible for flavor) |
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Term
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Definition
| Milk proteins coagulate due to lactic acid fermentation? |
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Term
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Definition
| Curds are formed, curd is pressed so water is removed then salted, product then may be inoculated one or two times depending on the variety |
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Term
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Definition
| Churning milk causes fat globulins to aggregate and seperate from the watery buttermilk |
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Term
| Yeast grows under what type of conditions? |
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Definition
| Aerobic whch results in increased CO2 production and some EtOH accumulation |
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Term
| What is special about Baker's Yeast? |
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Definition
| Selected strains of saccharomyces cervisiae produce enzymes that hydrolyze the starch and carbohydrates found in the grains used for baking |
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Term
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Definition
Cabbage is shredded and wilted with addition of NaCL
Brine which forms lactic acid bacteria and restricts growth of gram negative bacteria
two microbes responsible for production are Leuconostoc mesenteriodes (drops pH to 3.5) and Lactobacillus plantarum (dominant fermenter) |
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Term
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Definition
juice- white wine the seeds and skin is taken out
this is the must and is pasteurized
it ferments for 3-5 days at 20-28* C final product contains 10-18% EtOH
Sediments removed by racking
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Term
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Definition
malting- Grains are mixed with water and allowed to germinate for one week, then crushed to release enzymes
mashing- the enzymes in the malt hydrolyze the starches and proteins when incubated at 70*C
mash is heated with hops, solid settles
the clear liquid is called the wort and is heated to pitched- fully inactivate the hydrolytic enzymes and inoculated with yeast
then fermented |
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Term
| the major effect of temperature |
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Definition
| affect the velocity of enzyme catalyzed reactions |
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Term
| What happens when milk gets pastuerized? |
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Definition
| nucleic acids and proteins get denatured and membrane lipids melt |
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Term
| Common milkborne pathogens |
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Definition
mycobacterium tuberculosis, salmonella, strep and brucella
NOTE THESE DO NOT FORM SPORES |
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Term
| What is the only way to achieve heat-sterilization? |
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Definition
| Steam sterilization, in an autoclave |
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