FOOD MICROBIOLOGY (With complete solution)

Define: microbial ecology correct answers How a microorganisms interacts with physiochemical and biological aspects of its environment; food in this case Which 2 growth phases are the most important in spoilage of food correct answers Lag and exponential phases What are intrinsic paramters, name all six correct answers Affect the inherent part of the tissues. -Nutrient Content -Aw -pH/Buffering Capacity -Oxidation-reduction potential (Eh) -Antimicrobial constituents -Biological strucures What are extrinsic paramters, name the 3 correct answers physical aspect of the storage environment that affects both food and microorganisms. -Temperature of storage -Relative humidity -Presence and [gases] What are implicit parameters, name all 3 correct answers properties and interactions of microorganisms present: -growth rates -mutalism/antagonism/commensalism -cell-cell communication What do intrinsic,extrinsic,implicit parameters along with processing factors affect... correct answers growth of microbes in food In relation to nutrient content, list in order from lest fastidious to most fastidious. Yeasts/gram (+/-)/mold correct answers molds<yeasts<gram negative<gram positive bacteria Name six nutrient categories correct answers Carbohydrates, lipids, proteins, Vitamins, minerals and other N-containing compounds What is water activity and what reduces it. correct answers Aw: the measure of free or available water = vapour presure of solution/food (p) / vapour pressure of solvent/water (p0) Ice, crystallization, colloid gel substance Also inc. salt dec. water activity. Does water content proportionally reflect water activity? correct answers No --> grains/rice/dried fruit