Milk decay RP

what happens when milk goes off (RP)

bacteria in it breaks down lactose into lactic acid, decreasing pH

role of lipase in milk RP

speeds decay up and breaks down lipids in milk to produce 3 fatty acids, and glycerol. The fatty acids decrease the pH and make it acidic

indicator of milk RP

phenolphthalein is pink at alkali and colorless at acid

why is sodium hydrocarbonate added to milk for the decay RP

to make it alkali so phenolphthalein works

milk RP basic method

milk alkali solution is heated up and lipase is added. it is stirred continuously while a stopwatch goes until it goes colourless (white) and acidic

milk decay RP resuts

rate of decay increases with temperature until a temperature where it sharply drops due to denaturing