Lab 2 - Food microbiology and enumeration

regulating the safety of drinking water

what is EPA responsible for

non-meat food plus food additives, seafood, wild game, eggs in the shell, and bottled water

what is FDA responsible for

raw fruits and vegetables, meat/poultry, and processed eggs

what is USDA responsible for

high heat, cooling, drying, lowering pH, antimicrobials, protection from environment, and behavior

7 types of controls in place for food manufacturing

40-140 Fahrenheit → foodborne bacteria can easily multiply

what is the danger zone?

wash hands, don’t use canned food when it’s bursting, wash fruits and veggies, etc

ways to practice food safety at home

gram-negative bacilli capable of fermenting lactose often found in feces of war-blood animals (serve as a fecal indicator)

what are coliform bacteria

the source is fecal contamination and could contain pathogens 

what does it mean if coliforms are detected?

MCA → grows gram-negative organisms and shows lactose fermentation 

what plate do we use to detect coliforms 

serial dilutions

what do we use if microbial samples are too dense to count?

colony forming units

represents one cell that was healthy enough to divide enough times to form a visible colony of bacteria on an agar plate

30-300

what is the countable range of colonies?

spread plating

technique used to evenly distribute microbes from a liquid sample or culture across an agar plate

CFU of coliforms / CFU of normal plate * 100

calculate percentage of coliforms