Food and Industry Microbiology Flashcards
What do all edible microbes have in common
They are fermented
What is anaerobic fermentation used for
used to process a wide variety of food
What does acid fermentation produce
-produces organic acid fermentation products, like lactic acid in cheese
What does alkaline fermentation produce
produces basic fermentation products, like ammonia in natto
What does ethanolic fermentation produce
produces ethanol and carbon dioxide, like in beer
What are the benefits of fermenting foods
-preservation: waste products increase food shelf life
-improved digestibility: microbes break down molecules we cannot, increase a food’s nutritional value
How do you make cheese
-start with curds of milk (pH is about 6.6)
-lactobacillus and streptococcus ferment lactose to lactic acid, acidifying the milk
-as mild acidified, caseins destabilize and begin to clump together
-the initial result is yogurt
-rennet or another protease is added to continue breaking down casein OR heat is added to denature casein
(soft cheese like cottage cheese do not have rennet added)
Why does swiss cheese have holes
propionibacterium freudenreichii ferments lactate to propionate, producing CO2 as a biproduct
What is the purpose of soy fermentation
-soybeans are high in protein, but also have compounds that make them difficult to digest
What is different about alkali fermentation
increases instead of decreasing pH
What is made with ethanolic fermentation
bread beer, and wine made from
YEAST and
CO2 is produced
How does food spoil
-enzymatic processes
-chemical reactions
-microbial processes
What is bioprospecting
the search for organismis with potential commercial applications
