Food Technology- Exam Unit 1 :Food Technology- Exam Unit 1


Chemical properties of foods :Chemical properties of foods The nutrients that are present in foods.


What are the sensory properties of food? :What are the sensory properties of food? AFTA Appearance Flavour Texture Aroma


Sensory Evaluation Techniques :Sensory Evaluation Techniques Hedonic Scale- Usually used for children, a very basic measure of whether or not it was a good product using a smile rating. Descriptive Test- AFTA used to explain a product the various aspects of a product in more detail. Ranking- Tasters have to compare product’s properties and rank from lowest to highest.


Safety and Hygiene Practises :Safety and Hygiene Practises Bread making Ensure you use oven mitts when removing hot bread pans from the oven to prevent burning yourself. Ensure that bench surfaces are clean and dry for kneading the dough. Ensure that all of your equipment is clean and dry before use.


Safety and Hygiene cont… :Safety and Hygiene cont… Bread making Do not wear excessive jewellery as it will be touching the dough as it is kneaded. Ensure that hands are clean and dry before kneading dough. Ensure that oven door is closed when finished.


Considerations when buying food :Considerations when buying food Is the item perishable? When is the expiry date? Is the packaging damaged? Is it fresh? What is the quality of the product? How should it be stored?


Danger Zone :Danger Zone


What is Food Contamination :What is Food Contamination The occurrence of chemical, biological, physical or other substances in food that make it unsafe for consumption. Physical contamination- hair, insects, band-aid etc. Chemical contamination- detergents, sprays etc Biological contamination- yeasts, moulds, bacteria. (needs time, certain temperature and moisture in products)


What are the micro- organisms that can cause food spoilage? :What are the micro- organisms that can cause food spoilage? Yeasts, moulds and bacteria. Eg. Salmonella poisoning – in highly processed meats that do not get recooked to kill the bacteria that grow.


What is food poisoning? :What is food poisoning? Food poisoning is caused by bacterial contamination of food (most common occurrence and regular symptoms), chemical contamination and physical contamination.


The 2 to 4 Hour Rule :The 2 to 4 Hour Rule If a product is in the danger zone for less than 2 hours- refrigerate, or use immediately If a product is in the danger zone for 2-4 hours- use immediately If a product is in the danger zone for 4 hours or longer- Do not use, throw out immediately


Hazards in a small food scale operation :Hazards in a small food scale operation Lack of refrigeration Can’t keep hot food hot, cold food cold Dirty surfaces Lack of rubbish bins Food not covered/ protected Food left out in the danger zone for a long period of time


Vegetables :Vegetables Bulbs Flowers Fruits Stems Roots


Legumes and Pulses :Legumes and Pulses Legumes- pods with seeds Pulses- Dried, edible seeds of leguminous plants. They both contain complete proteins.


Fruit :Fruit Fruits are the edible parts of a plant that contain the seed (s) Stone fruits Citrus Fruits Tropical fruits Berry fruits Exotic fruits Melons


Why is it better to purchase fruits and vegetables when they are in season? :Why is it better to purchase fruits and vegetables when they are in season? Usually cheaper to purchase Have better flavour Have a high nutritive content They are more readily available


Pectin :Pectin Found in fruit an vegetables and holds plant cells together. It is used in jams and jellies as a thickening agent.


Carbohydrates found in vegetables :Carbohydrates found in vegetables Sugar Starch


Gluten :Gluten Gluten is the main protein found in wheat products. Gluten gives dough elasticity, resulting in the springy properties of bread.


Dextrinisation :Dextrinisation Starch is partially changed by heat, acid or enzymes to form dextrins


Aeration :Aeration The process of incorporating air into a substance. Makes product porous and light. E.g sifting, creaming etc.


Selection and storage of cereals :Selection and storage of cereals Keep sealed in an air-tight container Do not purchase if there is evidence of moisture


Cereal Grain :Cereal Grain


Cereals :Cereals The seeds of grasses


Denaturation :Denaturation An irreversible change in proteins that occurs as a result of heating or the addition of acids. Changes the structure of proteins


Coagulation :Coagulation The formation of a clot in proteins as a result of denaturation. (chunky bits and fluid separate)


How should chicken be cooked to maintain its optimal properties :How should chicken be cooked to maintain its optimal properties Lowest heat, longest time


How to tenderise meat :How to tenderise meat Meat may be tenderised by adding moisture to a product- e.g marinade, stewing, simmering Meat may be tenderised mechanically- e.g finely scoring the surface, pounding with a meat mallet, rolling meat.


Offal :Offal The leftover edible organs of an animal- e.g liver, brains, kidneys, heart, tripe etc


Meat preperation :Meat preperation Ageing- hanging meat for a period of time allowing it to tenderise Cryovac- ages meat under vacuum in a plastic bag Larding and Barding- when fat is placed on top of or inside a product that is being roasted.


Categories of Seafood :Categories of Seafood White fish- e.g whiting, flathead tails, snapper, ets Oily fish- e.g tuna, salmon, sardines, etc Shellfish -Crustaceans (e.g crab, lobster, prawns, etc) -Molluscs (e.g oysters, scallops, mussels, etc)


Preparing Seafood :Preparing Seafood Grilling Poaching Steaming Baking Deep- frying


Storing fish :Storing fish Fish should be stored in the fridge or freezer. It should be cleaned and scaled when stored and should be covered.


Testing freshness of eggs :Testing freshness of eggs Floating test- if it floats in a bowl of water it is stale, if it sinks it is fresh. Plate test- if a egg is cracked and the yolk and white are both slightly raised and keep their shape the egg is fresh, if it is watery and doesn’t keep shape it is stale.


Structure of an egg :Structure of an egg


Milk Products :Milk Products Full- cream milk Low- fat milk Soy milk Coconut milk


Pasteurization :Pasteurization Involves heating the milk to a temperature high enough to kill disease-producing bacteria


UHT Milk :UHT Milk UHT – stands for ultra heat treated UHT Milk is heated to 135 degrees celcius and held for 2-3 secs, then rapidly cooled and hermetically sealed.


Functional properties of milk in food preperation :Functional properties of milk in food preperation Enhances flavour Adds nutritional value Provides a smooth texture


Lipid :Lipid The term used for fats and oils. Lipids are comprised of hydrogen, carbon and oxygen. E.g butter, olive oil, canola oil, vegetable oil, etc


4 Types of Fat :4 Types of Fat Polyunsatured Mono- unsaturated Saturated Transfats The best fats for us to consume are mono- unsaturated fat products- plant based fats


Functional properties of fats and oils :Functional properties of fats and oils Flavour Basting- add crispness to product Add moisture to foods Assist in browning Frying Aerating Prevents products from sticking


Purposes of salt in food production :Purposes of salt in food production Used as a flavour enhancer Used as a colour enhancer Used as a preservative


Functional Properties of Sugar :Functional Properties of Sugar Sweetness Preservatives and additives Absorbs moisture Bulking agent Aids in temperature control of products Colour enhancer Flavour enhancer


Crystallisation :Crystallisation Dry sugar is heated to produce a syrup and then cooled, producing a cystallised product. It can only occur in a super-saturated solution.


Rancidity :Rancidity Fats and oils become rancid as a result of oxidation. They get a sour smell and an acidic taste.