Food Tech: Provenance

Where do different sweeteners come from?

Sugar - Sugar cane / sugar beet

Honey - Bees make it from nectar

Maple syrup - Sap of maple tree

Label a fruit cell

Vacuole - sap, sugar, pigments, salts

Cytoplasm - Jelly, pigments, fat

Cell wall - cellulose (NSP)

What are the categories of fruits and some examples?

Category	Examples
Citrus	Lemon, orange, limes
Soft / Berries	Black currents, blue berries
Hard	Apples, pears
No category	Bananas, melon, kiwi

What causes colour in vegetables?

• Chlorophyll - green

• Carotenoids - orange / yellow

• Anthocyanins - Blue / Red (beetroot)

What are the categories of vegetables and examples?

Leaves	Cabbage, spinach, lettuce
Fruit	Cucumber, aubergine, peppers
Roots	Carrot, beetroot, swede
Flowers	Broccoli, cauliflower, artichoke
Bulbs	Onions, leeks, shallots
Stems	Celery
Tubers	Potatoes, yams
Seeds / Pods	Peans, runner beans, broad beans

Advantages and disadvantages of locally produces fruit and veg

Fresher	Less choice
Less food miles	Different sizes
Less energy for transport	More expensive
Supporting local farmers

What benefits do green/glass houses have?

• Control and monitor conditions

• Increase yield

• Grow foods out of season

What are the categories of meat and examples?

Offal	Kidney, liver, tongue
Poultry	Chicken, turkey, goose, duck
Game	Venison, rabbit, pheasant
Meat	Beef, lamb, pork

How is CHicken reared?

• Barn cage

• Laying cage systems / enriches colony cages

• Free range

• Organic

What does the red tractor logo mean?

The food comes from farms and food companies that meet industry standards for food safety & hygiene, animal welfare and environmental protection.

What is intensive farming of crops?

• Uses chemicals and pesticides to increase yield → (Concerns about long term health affects on us & environment)

• Also called factory farming

What is intensive farming of animals?

• Kept indoors to control their diet, movement, breeding and disease control

• This maximises yeild

What is organic farming? Why do people choose it?

• Grown without chemicals or artificial fertilisers or pesticides

• Animals raised without growth hormones or antibiotics.

• No genetically engineered ingredients

• Certified by the soil association

Tastes nicer, respects environment and wildlife, concerned about health affects of chemicals.

How are fish caught? 10 methods

Trawling	Common. Nets, pulled along sea bed
Dredging	Metal cages pulled across sea bed
Gill netting	Curtains of net suspended in sea
Harpooning	Lunge a long metal pole into fish
Jigging	Grappling hoot attached to line targets fish
Long lining	Lines for miles, strung with bait
Pole & line	Fishing pole and bait targets fish
Purse seining	Large net around school of fish
Traps and pots	Wire cages with bait put on sea floor
Cyanide	Explosive stun or kill fish so easier to catch

What are the categories of fish and examples?

White (round)	Cod, haddock
White (Flat)	Plaice, dover sole
Oily	Tuna, salmon, sardines, herring
Shellfish, molluscs	Oysters, scallops, mussels
Shellfish, crustaceans	Lobster, crab, prawns

What does sustainable fish supply mean?

Farmed or caught with minimal damage to the marine environment and other wildlife.

Marine Stewardship logo confirms sustainable fishing.

What can be done to make catching fish more sustainable?

• Larger holes in nets to let smaller fish out

• Releasing unwated species if accidentally caught

• Sinking long lines deeper to reduce bycatch

• Set up marine reserves to allow stocks to recover

What are the three groups of fish farming?

Farming - Whole process is in captivity

Sea rearing - Young fish caught in wild, grown in controlled environment

Sea ranching - Young fish bread in captivity then released into the wild.

What are the advantages of fish farming?

• Less transport - grown near to market

• Produce higher quantities

• Doesn’t reduce wild fish stock

• Protected from weather changes

• Cannot escape

• Protected from predators

What are the disadvantages of fish farming?

• Expensive to run

• Fed fish which would be food for wild fish

• Use pesticides and antibiotics

• Drugs pollute surrounding water

• Waste is polluting

• Spread disease quickly

What is primary processing?

Processing raw materials into ingredients

Milling wheat into flour

Heat-treating milk

Extracting oil from crops

How is flour processed?

1. Cleaned - metal detectors & machine remove stones, metal. Air currents lift off dust

2. Conditioned - Pericarb softened by water so its easier to remove the floury endosperm

3. Gristing - Blended with other types of wheat to make different types of flour

4. Break rolls - Rolls rotating at different speeds shear open (dont crush) the grain and separate inside from outside

5. Reduction Rolls - Grain fragments are separated by sieves. Channeled through rolls for final milling into white flour

   (Any coarser pieces repeat rolling process until fine)

Label a wheat grain

How is milk processed?

• Milk is an emulsion (mostly water with fat globules)

• The milk is homogenised (forced at high pressure through small holes)

• This break up the fat and evenly disperses it through the milk

• Cream doesn’t sit on top

What methods of heat treatment are used on milk?

Pasteurised - Heated to 72ºc for 15 secs. Quickly cooled below 6º (destroys pathogenic micro-organisms. Stores for short time)

Sterilised - Heated to 104ºc for 40 mins. Cooled quickly (destroys nearly all micro-organisms & enzymes. Extends storage.)

UHT - Heated to 135ºc for 1 sec. Put in sterile, sealed containers (Extend storage up to 6 months unopened

Canning - Packed in aseptic cans, sterilised. (Double seam / hermetic seal)

What are Low temp methods of treating milk?

Cold temp slows bacteria growth (don’t destroy). Freezing temp (-18ºc) makes it dormant

• Chilling - Fridge 0-5º

• Blast Chilling - Reduces to below 3º in under 90 mins

• Cook-chill - Short-term preservation. 4-5 days Cooked to 70º, portioned, chilled within 30 mins. Reduced to 3º in 90mins. Must be heated immediately once out of fridge.

Advantages of cook-chill

• No skill to prepare

• Max quality fresh food for long time

• Save energy at home

• Available in single portions

• Little waste

• Consistent quality

• Doesn’t destroy nutrients

What is the danger zone?

The temp at which micro-organisms can replicate quickly

5º - 63º

How is flour made into bread?

1. Ingredients delivered to bakery

2. Mix ingredients at high speed. Dough is divide. Passes along conveyor belt and left to prove

3. Continuously kneaded for 2 mins. Dropped into pre-greased baking tins.

4. Second proving for about 50 mins

5. Bake in oven for 20 mins at 230º

6. Removed from the pan and cooled for up to 1.5 hours. Passed down conveyor for slicing and to be bagged.

What is milk made into?

Butter - Churning cream to remove liquid

Yoghurt - Fermenting milk with harmless bacteria (Milk pasteurised, homogenised, incubated with bacteria, left to set to reach correct acidity, add flavours)

Cheese

How is cheese made?

1. Milk pasteurised, cooled to 30º

2. started culture of bacteria added

3. Rennet added and left to set

4. Curd is cut so whey is released (soft → whey drains naturally, hard → curd heated and put on top of each other to release more whey)

5. Cheese is milled, pressed into moulds

6. Left to ripen

What is clarified butter?

Melt butter and use the fat that rises to the top.

Ghee is a form of clarified butter

What are the different types of cheese?

Hard	Cheddar, Parmesan
Semi-hard	Cheshire
Soft ripened or bloomy rind	Brie
Blue	Blue stilton
Washed rind	Stinking Bishop
Fresh	Mozzarella, cottage cheese

What are the advantages of preserving?

• Lasts longer, shop less, longer shelf life

• Buy products when out of season, more rnage of foods

• Prevents micro-organisms multiplying

What are the disadvantages of preserving?

• Contains lots of fat, sugar and/or salt

• Not much fibre

• Lose nutrients during processing

• Additives to restore colour lost in processing

• More expensive

Why are frozen food products increasing?

• More choice

• Saves time

• Extends shelf life

• More consumer demand

• Lack of cooking skills

What are some methods of Freezing?

• Blast - -30º / -40º cold air circulates. Stored at -20º / -30º (fish, pizza, ready meals)

• Fluidised bed - freeze small fruits and veg so they don’t stick together. Air causes food to float above conveyer (peas, raspberries)

• Plate - between 2 cold plates (regular shaped foods only, ready meals, fish)

• Cryogenic freezing - liquid nitrogen -190º (raspberries, prawns, strawberries)

Ways of dehydrating foods

Cheaper, easier to transport, long shelf life

• Sunlight - slow evaporation: raisins

• Fluidised bed drying - Clump dry particles into granules: potato, coffee

• Accelerated freeze-drying AFD - quick frozen, then placed in vacuum under pressure. Heat vaporises ice to steam

• Oven-drying - warm oven: herbs, teas, veg

• Spray drying - foods which may be damaged by too much heat: milk, coffee

• Roller drying: baby foods, mash potato

Methods of Chemical preservation

1. Smoking - over wood, gives flavour

2. Add acids, salt, sugar

   Vinegar - bacteria can’t survive in low pH

   Salt - ham / bacon / fish like tuna in brine (salt and water solution) Reduce water via osmosis

   Sugar - Reduces water, so no bacteria. Preserves. candied fruits.

Methods of Modified / controlled atmosphere packaging MAP / CAP

Slows bacteria growth, lack of oxygen, longer shelf life (bananas/cheese)

Package fresh foods in peak condition. ‘Gas flushing’ O2 N CO2 Sealed with hermetic seal

Vaccum packing - remove air (anaerobic), prevent bacteria growth, maintains taste and flavour