milk, yoghurt & cheese

Question 1

milk (nb)

Answer 1

considered a complete food: easy 2 digest & contains all 5 nutrients + water

Question 2

milk processing

Answer 2

reasons:

• makes safe 2 drink
• prolongs shelf life
• improves flavor

types:
pasteurisation, homogenisation

Question 3

pasteurisation

Answer 3

milk heated to 72° for 25 seconds,
cooled quickly before packed into cartons or bottles.
kills pathogenic bacteria without changing the taste. destroys any vit c present.
pasteurised milk lasts 3-4 days in fridge

Question 4

pathogenic

Answer 4

disease causing

Question 5

homogenisation

Answer 5

distributes fat in milk; improves flavour

carried out after pasteurisation

Question 6

types of milk

Answer 6

whole (3.6% fat)
low-fat (1% fat)
skimmed (.3% fat)
fortified 
protein 
lactose-free
long-free (VHT)
buttermilk
flavoured
dried 
evaporated
condensed

Question 7

whole (3.6% fat)

Answer 7

pasteurised and homogenised

suitable for young children

Question 8

low-fat (1% fat)

Answer 8

much fat removed

suitable for adults on low-cholesterol and low-calorie diets

Question 9

skimmed (.3% fat)

Answer 9

almost all fat removed

suitable for adults on low-cholesterol or low-calorie diets

Question 10

fortified

Answer 10

fortified with calcium, b group vitamins (folic acid incl.), vit d + e
suitable for everyone

Question 11

protein

Answer 11

much fat removed
xtra protein (100g p/litre)
popular w ppl following strength & conditioning programmes

Question 12

lactose-free

Answer 12

lactose removed

useful for ppl w lactose intolerance

Question 13

long-free (vht)

Answer 13

heated 2 high temps to kill all bacteria present
keeps for months if unopened
common in warm countries

Question 14

buttermilk

Answer 14

acidic liquid left after butter made

used in baking (eg brown soda bread)

Question 15

flavoured

Answer 15

flavourings added

can b high in sugar

Question 16

dried

Answer 16

moisture removed
useful 4 camping & emergencies
keeps 4 long time in sealed tin
example: baby formula milk

Question 17

evaporated

Answer 17

some water removed , milk sterelised, sealed in can
keeps 4 over yr
used in desserts, 2 enrich sauces, as coffee creamer

Question 18

condensed

Answer 18

some water removed , sugar added, milk sterilised, sealed in can
keeps 4 over yr
used in desserts (eg caramel slices)

Question 19

nutritive value of milk

Answer 19

hbv protein (repair + growth, heat + energy)
saturated fat (heat + energy, layer of fat around organs + body, vitamins a d e + k)
lactose
vit a, b group vits, vit d (a: eysight, linings of mouth nose + throat, growth, eyes skim + hair; b group: controls energy released from food, nervous system; d: works w calcium)
calcium (bones, teeth 4 young, g bone density 4 older), phosphorus, potasum
water (body tissues + fluids, transports nutrients + oxygen, removes waste, regulated body temp

Question 20

dietetic value of milk

Answer 20

easily digested: preg women, older ppl, invalids, convalescents
fat removed (low-fat + skimmed): low-calorie + low-cholesterol diets. lack vits a + d: don’t serve 2 young children
high calcium content: children, teens, pregnant women
refreshers + hydrates
nutritious + inexpensive: low-income families

Question 21

milk: complete food

Answer 21

lacks fibre, vit c & iron. should b combined w food high in these nutrients 2 create balanced meals
example: milk w wheetsbix, boiled egg, brown bread, glass of oj makes balanced breakfast

Question 22

yogurt nutritional & dietetic value

Answer 22

similar to that of milk.

probiotic yoghurt has ‘healthy’ bacteria added to aid digestion & strengthen immune system

Question 23

cheese enzyme

Answer 23

rennet
found in stomachs of grass-eating animals.
there is also a vegetarian rennet

Question 24

production of cheese

Answer 24

1. pasteurisation (raw milk pasteurised; 72° for 25 secs)
2. starter culture added ( lactic acidosis bacteria added; changes lactose in milk to lactic acid. adds flavour & preserves cheese)
3. rennet added (milk heated 2 30° & enzyme rennet added. milk then separates into curds & whey - process that takes 40 mins)
4. cut & drained (salt added & curds are cut up + drained 2 allow more whey 2 drain off. if process stops here, cottage cheese is produced)
5. moulded (curds pressed into large moulds. more whey drained off. cheeses
   taken out of mould containers & left to mature so that flavours can develop. some cheeses mature 4 a year+)
6. packaged (cheese cut up into sizes suitable 4 sale & packaged)

Question 25

classification of cheese

Answer 25

``` hard (cheddar, parmesan) semi-hard (edam, feta) soft (cottage, brie) blue-veined (stilton, danish blue) processed (cheese strings, cheese triangles) ```

Question 26

average composition of hard cheese

Answer 26

protein: 25.4% fats: 34.9% carbs: 0% minerals: calcium vitamins: a, b group, d water: 36.6%

Question 27

nutritive value of cheese

Answer 27

``` excellent source of hbv protein high in saturated fat (esp hard cheese) most cheese contains no carbs excellent source of calcium vits a, b group, d water content depends on how hard/soft cheese is - the higher the water content the lower the fat content ```

Question 28

dietetic value of cheese

Answer 28

high hbv protein content - vegetarian diets relatively cheap protein food - low income limit full-fat cheese - low-calorie & low-cholesterol diets. useful: cheese made from low-fat milk (eg cottage cheese) high calcium content - diets of children, teens, pregnant women. low fat varieties - old people (maintains g bone density)

Question 29

culinary uses of cheese

Answer 29

``` snacks (on crackers) savoury dishes (pizza) salads (greek salad) sandwiches (croque madame) sauces (carbonara) dips & fondues (blue cheese dip) baking (çheese scones) desserts (cheesecakes) ```

Question 30

safe & hygienic practices 4 buying milk yoghurt & cheese

Answer 30

``` buy from hygienic shop check use-by date - often freshest products are shelved behind less fresh products buy in usable amounts to avoid waste ensure cartons/packs r properly sealed buy towards end of shopping trip ```

Question 31

safe & hygienic practices for storing milk, yoghurt

Answer 31

store upright in door of fridge to avoid spillages store at 4° to prevent it going off quickly use in rotation - check use-by dates & use oldest first avoid mixing milks w diff best-befor dates as all milk will go off at same time, ie earliest use- by date keep covered & away from strong-smelling foods (eg onions) as taste can b affected

Question 32

safe & hygienic practices for storing cheese

Answer 32

store at 4° to prevent going off quickly store in original packaging. of opened, wrap in wax paper or place on sealed container. if exposed to air, it dries out & become hard + inedible use before use-by dates 2 avoid waste

Question 33

effects of cooking on milk

Answer 33

protein coagulates (sets), forming a skin on milk steam builds up under skin, causing milk 2 boil over bacteria are destroyed b group vits destroyed flavour becomes sweeter

Question 34

effects of cooking on cheese

Answer 34

protein coagulates, causing cheese to shrink fat melts - overcooked cheese becomes greasy color changes as cheese browns if overcooked, cheese becomes rubbery & indigestible, so add it at end of cooking