Dairy pt 5 Flashcards
list 6 milk products
- cheeses
- cream
- butter
- ghee
- ice cream
- fermented products
name 6 fermented products
- sour milk
- sour cream
- buttermilk
- yogurt
- kefir
- ititu
list the steps of the cheesemaking process
1) standardize milk
2) add ingredients (salts, lysozyme, nitrites)
3) mix or blend thoroughly
4) pasteurize
5) homogenize
6) treatment w/curdling agents
7) cut into cubes
8) separate curds from whey
9) ripening
what’s the purpose of adding salt to make cheese?
- draw out moisture from curd
- flavor
- acts as a preservative
- somewhat increase interactions between proteins
what’s the purpose of adding CaCl2 to make cheese?
it furnishes Ca2_ that forms insoluble calcium caseinate to facilitate coagulation
why is lysozyme added to the cheese making process?
acts as a preservative by breaking bacterial cell walls
why are nitrates/nitrites added to cheese?
destroy C. botulinum
what are some curdling agents?
- proteases (rennet, chymosin)
- acid (lactic, acetic, propionic)
why are rennet and chymosin better for curdling than other proteases?
- more specific for cleaving the k-casein bond between phenylalanine and threonine
- reduces potential development of off flavors & texture softening (less thorough proteolysis)
what does cutting the curds into cubes do?
further removes moisture, enhances hydrophobic interaction between proteins to form firmer curds w/relatively lower moisture content
list some ripening agents
- enzyme cocktails
- microbial cultures
- salt
- color
- flavor
describe what the enzyme cocktails are like as ripening agents
mixture of proteases and lipases
- proteases: break down proteins to form peptides and free AAs, leading to bitter peptides
- lipases: break down fats which produce free FAs which induce the desired cheese flavors
describe what the microbial cultures are like as ripening agents
able to produce desired enzymes and acids (lactic, propionic)
how are acetic and propionic acid related?
propionic acid can be broken down to acetic acid and CO2
give examples of pigments applied to cheese during the ripening stage
carotenes, chlorophylls
what kind of flavors are imparted during the ripening stage?
- moldy
- bitter
- fruity
what are some ways that cheeses are classified?
based on:
- milk source
- means of curdling
- fat content
- cultures used to ripen cheese
list types of cheese based on their milk source
goat, sheep, cow, buffalo
list types of cheese based on their means of curdling
enzyme assisted, acid assisted
which curdling method produces greater yields of curd?
acid
list some cheese types based on their moisture content
- soft
- semi soft
- semi hard
- hard
- extra hard
list some cheese types based on their fat content
- skim milk cheese
- low fat
- semi fat
- fat/whole fat
- cream
- double cream
which type of cheese has the most fat?
double cream
what examples of cheeses can be made with mesophilic bacteria? what is the temperature range?
- cheddar
- blue cheese
28-40
what examples of cheeses can be made with thermophilic bacteria? what is the temperature range?
- parmesan
- mozzarella
- swiss
>40
what is cream?
the fat phase of milk separation via gravity or centrifugal separation
what products can be derived from cream?
- butter
- ghee
how is butter made?
after pasteurizing the cream and subjecting it to rapid churning a lower temps of 10-18C, the fat globules begin to coalesce and crystalize. more churning = bigger crystals.
true or false: buttermilk is high in fat
false, it’s practically devoid of fat
how is buttermilk made?
it’s the liquid byproduct of butter production
how is ghee made?
further processing of butter using heat. Ghee is the golden liquid portion and rest is residues
what is the first 4 steps to ice cream making regardless of the type of ice cream?
- obtain ingredients/raw materials
- mix
- pasteurized
- homogenize
how is soft serve ice cream made?
1) first 4 steps
2) age at 0-4C
3) freeze at 5C
then we add other ingredients
how is hard ice cream made?
1) first 4 steps
2) age at 0-4C
3) freeze at 5C
4) packaging
5) hardening (-34C)
6) storage (-18C)
7) transportation
