3.1.3 Micro-organisms and Food Production Flashcards
What are micro-organisms used for?
to make many food products like bread, cheese, yoghurt and wine. and have been used since ancient times. food manufacturers use them to make foods by fermentation
How is yeast used in food production?
it is used as a raising agent in foods and in the brewery industry to ferment grapes into wine and beer from hops
How is bacteria used in food production?
used in cheese in the form of starter culture (lab grown bacteria) at the start of cheese making process along with rennet and salt. starter culture converts milk sugar lactose into lactic acid which begins the yogurt/cheese making process
How is mould used in food production?
provides wide variety of flavour + texture to food. such as cheeses (brie/stilton). moulds used to ripen surface of some sausages, improves smell + texture + shelf life (salami/pepperoni). moulds and yeast used in production of soy sauce
What are some examples of fermented foods?
kombucha, kefir, tempeh, soy sauce, miso, kimchi, ginger beer
What are the steps in cheese production?
milk is pasteurised, bacteria culture added, rennet enzyme added, curds cut to release watery whey, whey is collected and drain, curd piled up and release more whey, curd heated and cut to develop texture, cheese salted and pressed
Why is milked pasteurised in cheese production?
because its perfect food for bacteria to grow in, pasteurisation destroys pathogenic bacteria
Why is bacteria culture added in cheese production?
it turns milk sugar (lactose) into lactic acid. which coagulates milk protein and adds flavour + texture as well as acting like a preservative
What is coagulation?
the process of a liquid changing to a solid/semi-solid state
What does rennet do in cheese production?
rennet is an enzyme that clots (coagulates) the milk proteins (curd and whey)
What is done with collected whey?
used to manufacture baked products as ‘whey protein’
What happens after the cheese is salted and pressed?
it is then r`ipened which matures the cheese, the longer its ripened the stronger and more mature the cheese will be
How are micro-organisms used in bread production?
special nonpathogenic baker’s yeast is used. given correct conditions starch is broken down in the flour and adds flavour and produces CO2 gas bubbles which make the dough rise (fermentation)
What else is produces during fermentation when making bread?
alcohol is produced which adds flavour and escapes the oven and evaporates
What are the 3 types of yeast used in bread production?
fresh, dried, fast acting
