Micro chapter # 30 food microbiology

What are factors that influence the growth of microbes and foods?

Water, pH, nutrients, temperature, O2, hard coverings, natural antimicrobial compounds

Describe cross contamination

Bacteria in raw meat are allowed to contact other foods or utensils, which are then not cooked or cleaned properly

Describe the production of cheese

(1) Soft cheese, such as cottage and ricotta = lactococcus, streptococcus are added to milk and allowed to ferment, then heated and drained (rennin)

(2) hard cheese. The enzymes running is added to increase coagulation then it is also salted press, cut, and aged examples are Swiss cheese and cheddar cheese = contains propionibacterium.

(3) semi soft cheese like Roquefort, gorgonzola Stilton = contain penicillium

Limburger = contains brevibacterium

Yogurt

Contains streptococcus or lactobacillus is added to milk and heated for silver hours to produce aldehydes and acids

Pickled vegetables

The vegetables are placed in an anaerobic environment with salt or vinegar and the bacteria that are naturally on the vegetable cause it to ferment in 2 to 4 weeks. The bacteria are usually leuconostoc or lactobacillus

Processed meat products

The meat is grounded, then sugar, salt, nitrate, and lactobacillus or pediococcus or added, then it is incubated for several days smoked dried.

Alcoholic beverages

(1) For wine grapes are crushed SO2 added extra yeast added, strained several times aged in container containers

(2) for beer greens are mashed and soaked with sugar from various sources until it ferment flowers from the hop plant are added to make it bitter boiled Fuge yeast added fermented more age filtered

(3) for hard liquors, not boiled different greens types of yeast types of containers, and sometimes added bacteria affect flavor

Vinegar

Alcohol is sprayed over acetobacter or glucanbacter and the bacteria convert the alcohol into vinegar

Bread

Yeast is added to various ingredients and allowed to ferment a short time then baked sourdough has yeast plus lactobacillus pumpernickel has yeast plus leuconostoc

Soy sauce

Soy beans are mashed then salt is added then the mold aspergillus is added, and the material is allowed to ferment then lactobacillus and yeast are added and allowed to ferment. Then it is filtered and preservatives are added to stop the growth of the fungi and bacteria.