food quality Flashcards
safe storage of food: methods of storing foods
dry storage: room temp, well ventilated and spacious areas
cold storage: refrigeration and cool rooms 0-4 degrees
freezing: storing food for a long period of time below -18 degrees. microbes do not activate or grow because there is no exposure to air
perishable vs non-perishable foods
perishable: go off quickly, enzymes grow quickly (less than 7 days) e.g. cold meats, fruit and vegetables, fish and dairy - KEEP IN COLD STORAGE
non-perishable: canned, dried, preserved foods, enzymes do not grow quickly due to their environment e.g. rice, flour, pasta, canned sauces - KEPT AT ROOM TEMP
safe preparation and presentation of food: safe and hygienic work practises
PHYSICAL: caused by foreign objects, such as hair, dust, dirt, jewellery and pests, entering food during preparation or service.
-cover food and hair
-wear gloves over open wounds
-regular pest control
CHEMICAL: occurs when chemicals such as pesticides or detergents get onto food.
-keep chemicals away from food
-safe chemicals to wash, clean and sanitise equipment
-wash fruit and vegetables before use
MICROBIOLOGICAL: single-celled organisms that multiply rapidly to spoil food e.g. moulds, viruses, yeasts and bacterias
CROSS CONTAMINATION: the transfer of food with bacteria from one source to another e.g. when bacteria from raw, uncooked food spreads to cooked food.
safe preparation and presentation of food: methods of cooking
MOIST HEAT: low temps with liquid (steaming, poaching, slow cooking meats)
DRY HEAT: high temperatures directly onto food (roasting, bbq, grilling, frying meats)
MICROWAVE: transfer of energy to food in electromagnetic radiation
safe preparation and presentation of food: plating, styling and photographing
-contrasting colours, garnishes and utensils
-variety of shapes and sizes to provide dimension
-range of textures, such as crispy chips with soft, flaky fish
-ensure the main ingredient stands out
-a focal point that draws attention immediately
-software, apps, artificial lighting and lights, digital editing, and props
sensory characteristics of food
appearance: colour, shape, size and surface texture
colour, odour, taste and texture
functional properties of food: the role of proteins DENATURATION AND COAGULATION
DENATURATION: breakdown of the protein as hydrogen bonds break, and the coiled strands of the proteins begin to unwind. due to heat, agitation, acids, salts and enzymes
e.g. beating an egg
COAGULATION: occurs after denaturation, the already-separated strands of amino acids rejoin with new bonds due to heat, acids, and enzymes and create a physical change
e.g. cooking an egg, baking a meringue
-overcoagulation = stiffened proteins (syneresis) that is irreversible
functional properties of food: the role of proteins GELATION, FOAMING AND BROWNING
GELATION: when droplets of liquid get trapped in coagulated proteins
e.g. custard and soft cheeses
FOAMING: when air, or another type of gas, is spread through a liquid
e.g. meringues, pavlovas and souffles
BROWNING:
1. ENZYMATIC: enzymes cause oxygen to react with substances, resulting in browning (an apple)
2. MYOGLOBIN: food is exposed to air, resulting in browning (fresh meat)
3. MALLIARD REACTION: denatured proteins recombine with sugars under dry heat (toasting marshmallows, browning potatoes)
functional properties of food: the role of carbs
GELATINISATION: the breakdown of starch granules when heat is applied with a liquid, resulting in a thickened texture
e.g. pie fillings, custard, porridge
DEXTRINISATION: when a starch is exposed to dry heat, resulting in a golden brown colour
e.g. toasted bread/muesli, golden crust on cakes
CARAMELISATION: when foods with high sugar content, are heated above melting point resulting in a golden brown caramel
e.g. caramel, maple syrup, honey
CRYSTALLIZATION: when sugar is dissolved in liquid and it heats and evaporates, then cools to crystallize
e.g. toffee, fudge, brittle
functional properties of food: the role of fats
EMULSIFICATION: a mixture of two or more liquids that separate (oily and watery liquids together)
-temporary = it will separate again, e.g. vinegar and oil
-permanent = it cannot be reversed, e.g. egg yolk and vinegar/oil
AERATION: incorporating air into food products to increase the volume and create a light, airy texture
e.g. sifting flour and beating a meringue
functional properties of food: factors that effect functional properties of food
OXYGEN: too much can dry/brown food
TEMPERATURE: too low = undercooked, too high = overcooked, burnt and tough
ACIDITY: can speed up or hinder processes, provide stability, or cause curdling
AGITATION: can effect a functional property (possibility to over-stretch or deflate foods)
ENZYMES: can speed up or hinder the ripening process and tenderize foods
OTHER INGREDIENTS: impacts stability, thickness, texture and processes occuring e.g. sugar, salt and fats
