cloning and biotech Flashcards
lactobacillus bulgaricus and streptococcus thermophilus are what type of bacteria?
lactic acid bacteria
what does acidity do to the milk proteins?
dentures causing them to coagulate
what else does fermentation add to the milk?
flavours
what are probiotics?
stimulate immune system and improve digestion of lactose
what is the bacterium used in cheese making?
lactobassilicus
what sugar does this bacterium feed on (lactobacillus)?
lactose
what is the purpose of lactobacillus in cheese making?
prevent growth of unwanted bacteria
where does rennet come from naturally?
stomach of young mammals
what enzyme does rennet contain?
chymosin
what is the milk protein called?
caesin
what is the soluble form of caesin?
kappa- caesin
what does chymosin do to kappa- caesin?
converts to casein which is insoluable
which ions bind the casein molecules together?
Ca 2+
name three methods for separating the curd from the whey
cutting, stirring and heating
what is added to produce blue cheese?
penecillin
what type of respiration does yeast mainly carry out?
anaerobic
what are the products of yeast respiration?
CO2, ethanol
what causes the dough to rise
CO2
why does eating bread not make you drunk?
the alcohol evaporates in the oven
what is the yeast in wine brewing called ?
s. cerevisiae
where does s. cerevisiae grow naturally?
on the skin of grapes
what are the two sugars contained in grapes?
fructose and glucose
what are the products of wine fermentation?
co2 and ethanol
which grains are used to make beer?
barley
why are the grains allowed to germinate for a few days before being killed?
amylase converts starch to maltose
what is the purpose of drying the grains after they have germinated?
to stop maltose being used by seedlings, it would have no sugar to turn to alcohol
what do we called germinated dried barley grains?
malt
what is the enzyme that breaks down starch?
amylase
what is the sugar produced when amylase works?
maltose
what happens when yeast and water are added to the malt?
fermentation can begin
what is the substrate?
maltose
what are the products
ethanol and co2
what part of the plant do hops come from?
flower bud
why are hops added?
for flavour and to act as a preservative
what taste do hops have?
bitter
what flavour would beer have without hops?
sweet
what fungus is used to make quorn?
fusarium
give two advantages of quorn
no animal fat/ cholesterol
very high in protein
why may quorn be not as good as animal or plant protein?
different amino acid profile, no methionine
