Cooking products in dry heat in an oven. Shelf position in the oven is quite important the higher the shelf the hotter the oven temperature and the quicker the products will cook. Fan ovens blow the heat around and all the shelves cook evenly at the same temperature.
This means baking a product such as a pastry flan without the filling in the oven.
It helps to get the base layer of pastry really crisp. You can buy baking beans made from ceramic for baking blind. Cover the pastry flan with baking paper and drop in the ceramic beans to add weight and hold down the pastry. Lift the paper after about 15 minutes and check to see if the pastry has dried. If so, you can carefully remove the paper containing the baking beans and shoot them back into their storage jar ( take care they are HOT.) Allow them to cool and use again and again for baking blind.
Cooking in water ‘on the move’ at boiling point (100 C) on the cooker hob. Mostly a lid is placed over the pan to retain the heat and keep in the steam. The lid needs to allow some steam to escape or it will rattle so tilt the lid slightly on the pan. Usually boil is a first step and is followed by the term simmer which is a gently boil ( see simmer)
A slow and moist method of cooking that helps to make meat tender and vegetables soft and juicy. Rapid searing of the outside of a meat joint is followed by resting the meat on a vegetable layer. Enough stock or water is used to cover the vegetable layer. The cooking dish is then covered with either a lid or foil to sealing the cooking container. Cook gently at a moderate heat for up to an hour. Tougher cuts of meat such as topside or silverside can be cooked successfully this way.
To cook in a frying pan that is usually shallow and flat. Frying is carried out on the cooker hob. A stir-fry pan is deeper with sides that enable you to stir quite rapidly and cook over a high heat. It is wise to choose a non-stick frying pan.
Deep frying is using a deep pan on the hob at least one third to a half full of cooking oil. A basket is usually used to hold the product to be cooked this way and to drain off the oil when the product is cooked. It is popular for Indian products such as samosa and puri, and English products such as doughnuts and battered fish and chips! I would strongly recommend buying a thermostatically controlled deep-fat fryer for safety. Frying tends to give wonderful flavour and texture to food.
Stir-fry a method of cooking using a wok or a deep sided frying pan allowing the hob heat to spread up the sides thus cooking the food very rapidly. It is used for many Asian and Thai dishes.
Dry frying is using a frying pan on thehob and placing ingredients such as bacon, lardon ( cubes of bacon), chorizio, pancetta or sausages directly into the pan without adding any oil or fat. The frying actually begins once some fat from the product melts and begins to come out of the product and lubricate the pan. It extracts oil and fat from the product and uses it to cook the product.
A hot, intense and direct method of applying heat to a product. The grill compartment of the cooker should enable the grill tray to have shelf positions nearer or further away from the heat. Thin products are best as the heat can penetrate one side then you can turn it over and cook the other side. Best products are sausages, bacon, tomatoes and of course bread for toast. Always keep an eye on grilling it can be fast and furious.
Poaching is a gently moist method of cooking and is either carried out on the hob or in the oven. Either way requires the product to be covered with a well-fitting lid or a foil wrap. Moisture such as water, white wine, apple juice or stock is needed. Usually the base of the cooking container is covered in a thin layer of juice and the product laid into the moisture along with other flavourings such as bay leaves, star anise, black peppercorns or similar. Salmon fillets or whole fish can be poached. Medium heat is used to create steam to gently cook the product without drying it out.
A method of cooking in hot fat or oil in a hot oven. The fat can be meat fat such as lard or dripping. Oil is usually corn oil as it can be heated to a high temperature. Hot fat browns the food and give it a recognisable golden crispy coating. Roast potatoes are a good example of classic English roast potato. Modern cooking reduces the amount of fat by coating products in oil before cooking and laying the products on a tray. ‘Oven-bake’ is sometimes used as a cooking term for lower-fat roasting.
Cooking in water or stock just below boiling point. Usually you boil first and then turn down the heat so that the food simmers just below boiling point. It prevents boiling over!! This requires you to recognise that you need to control the temperature by adjusting the number or setting for the hob ring you are using.
Steaming is a fat free method of cooking that is suitable for vegetables and puddings. It can be carried out in a saucepan with a lid on the hob but usually a steamer tier or stack is placed over a saucepan and a top lid traps all the steam. If you have more than one layer you can cook cauliflower in one layer and carrots in another. This saves fuel and also makes good use of the hob, one pan cooking what might otherwise need two pans. You can buy electric steamers.
Using a microwave is a quick way to re-heat food products and to cook moist products. It relies on the microwaves juggling water in the food so that it gets hot and spreads the heat through the food. It is a good idea to rest the product for about 30 seconds to allow time for the heat to spread. Stirring helps the heat to spread and will avoid cold spots. Take care NOT to super-heat products such as coffee. Time is a very important control on a microwave.
FOOD SCIENCE terms
Acid: substances that turn universal indicator aperture shades of red. They form salts when they react with a base. Found in foods: citric acid in citrus fruits, tartaric acid in cream of tartar, ascorbic acid (vitamin c ) in fruits and vegetables, amino acids in proteins.
Alkali: substances that neutralise acids. Alkali is also called a base e.g. Acid plus base = salt plus water. Sodium bicarbonate is the most commonly used alkali in cooking.
Amino acids: molecules made up from carbon, hydrogen, oxygen and nitrogen. Phosphorus and sulphur are commonly linked as well.
Ambient temperature: Normal room temperature around 18?C- 20?C
Antioxidant: A substance, often an additive, which prevents oxidative rancidity of fats in foods.
Biological value: (BV) The value a protein food gives to the human body.
The effectiveness of a protein to enable growth and repair in the body.
Caramelisation: A process which occurs when sucrose is heated and changes in colour
from white to golden brown giving characteristic flavour change.
Carbohydrate: A substance made up from carbon, hydrogen and oxygen. Carbohydrate is a macronutrient, the major source of energy for the body.
Catalyst: A catalyst is a substance that increases the speed of a chemical reaction without being consumed by the reaction.
Coagulation: An irreversible process which involves the denaturation of proteins, changing from a soluble to an insoluble structure. As proteins coagulate they form crosslinks between themselves which’ holds’ or ’sets’ mixtures e.g. Raw eggs are coagulated by heat.
Collagen: The insoluble protein in connective tissue, tendons bones and skin of
animals and fish. It is converted to the soluble protein substance gelatine in the presence of
moist heat and therefore increases the tenderness of meat.
Colloid: a homogenous mixture made up of two phases one dispersed in another Eg milk is a fat in water colloid.
Control: Part of an experiment used to compare results
Denaturation: An alteration in the structure and shape of protein caused by heat, acid alkali or
mechanical action. It is an irreversible process.
Dextrinisation: the changed state of starch (dextrin) caused by application of dry heat.
Dextrin: Soluble compounds formed by the breakdown of starch by heat, enzymes or acids. Dextrins are formed in the presence of dry heat when bread is toasted.
Emulsifying Agents: Substances which help water and oily liquids to be uniformly dispersed together creating an emulsion.
Lecithin: is a natural emulsifying agent found in egg yolks. Surfactants are products used as emulsifying agents and help stablise emulsions.
Emulsion: A mixture of two immiscible liquids which can be stabilised or separate out on standing.
Enzymes: Natural protein substances which control other bio-chemical reactions. Eg. Ascorbic acid oxidase controls loss of vitamin C in cut fruits.
Fermentation: Chemical breakdown of sugars by the action of yeast or bacteria or enzymes eg grape juice to wine, soya milk to tofu, cream to creme fraiche. Products labelled as cultured or soured.
Foams: Formed when gas or air is introduced in quantity into a liquid or semi-liquid. Masses of bubbles are a characteristic. Egg white meringue, ice-cream and whisked sponge mixture are all examples.
Fortification: The addition of nutrients to manufactured foods to provide an increased intake and replace nutrients lost during processing. White flour is fortified with iron and Vitamin B (thiamin and niacin).
Gelatinisation: A process that occurs when starch is mixed with a liquid and heated. The
starch swells, absorbs and bursts as it gradually thickens the liquid. Used in saucemaking.
Gluten: A mixture of the low biological value proteins glutenin and gliadin that combine to form gluten when water is added to flour. Dough is formed with characteristic elasticity. Gluten is denatured by heat and loses elasticity. Gluten sets, helping to hold a risen structure of baked goods.
Gums: Substances used in food manufacturing to stabilize emulsions. Gums are hydrocolloids. Guar Gum See: Xanthan gum
Homogenisation: A process where milk (a colloid) is forced through fine nozzles to break
fat globules into fine droplets which are dispersed and remain dispersed throughout the milk. No cream line occurs on standing or during shelf life.
Humectant: Substances used in food processing, such as glycerol, which inhibit the loss of moisture from manufactured baked products. Humectants hold the water and prevent crystallization of sugar in confectionery and growth of ice crystals in frozen foods.
Hydrogenation: The treatment of oils by the addition of hydrogen under pressure which attaches to
unsaturated double bonds in the oil (lipid). Used in margarine or spread manufacture to firm up the oil to become a spreadable fat.
Hygroscopic: substance that absorbs moisture from the air. Sugars are hygroscopic.
Hydrocolloids: Colloidal structures that hold water. Gums
Indicator: A liquid that changes colour to indicate acid or alkaline.
Invert sugar: Produced by the hydrolysis of sucrose. Used in the manufacture of sweets as it prevents the crystallization of sucrose.
Lactic acid: produced by the fermentation of carbohydrate lactose in milk. Give characteristic flavour to fermented dairy products.
Lactose: A disaccharide formed from one unit of glucose and one unit of galactose. Found in milk.
Lecithin: An emulsifier naturally present in egg yolk. Helpful in making fresh mayonnaise and in cakes. Used as an emulsifier in manufactured foods.
Macronutrients: the nutrients in the diet measured in g. Protein, carbohydrate and fat.
Maillard reaction: A browning reaction, NOT due to enzymes, which occurs due to a reaction between carbohydrates and proteins during cooking at high temperatures. Responsible for meaty flavour and colour on the surface of roasted meat , and browning on baked goods where protein and carbohydrates are mixed. Eg. cakes
Mycoprotein: A (a fungi) compressed to form Quorn. An ingredient that provides a good source of protein.
Micronutrients: the nutrients in the diet measured in milligrams or micrograms, vitamins and minerals
Mixture: A mixture is a substance made by combining two or more different materials in such a way that no chemical reaction occurs. A mixture can usually be separated back into its original components. Some examples of mixtures are a tossed salad or salt water.
Myoglobin: A deep red tissue pigment that is responsible for the colour of meat. It holds
oxygen in the muscles and enables them to function
Oxalic acid: A substance present in rhubarb leaves and spinach, which is poisonous if consumed in large amounts.
Oxidation: the chemical reaction of a product with oxygen which might adversely affect flavour texture or colour of a product and limit shelf life.
Oxidative rancidity: Occurs in unsaturated fats and oils. The reaction is initiated by the
presence of some metals, ultra violet light and high temperatures.
Pasteurisation: The heat process used to make safe food e.g. milk or juice. Helps to prolonging the keeping quality of products by heating to destroy harmful bacteria.
pH is the level of acid or alkaline concentration of a substance, on a scale of 0-14 where 0 is very acidic and 14 is very alkaline
Plasticity: Capacity of a fat to melt over a range of temperatures enabling it to be firm, spreadable or melt.
Pectin: A complex polysaccharide, formed by some plants. It forms gels in water and is used
in the setting of jam.
Polypeptides: Long chains of amino acids used to form proteins.
Polysaccharides: Formed from long chains of monosaccharide units. Called starch, they are insoluble in cold water.
Polyunsaturates: Term used to describe the chemical structure of fatty acids with more than one double bond.
Pre gelatinised starch: Starches heat treated to speed up end cooking time e.g. quick cook pasta, quick cook rice, easy blend flour for sauces without lumps.
Preservatives: Substances added to some processed foods to prevent spoilage.
Probiotics: Live micro organisms which are added to foods and thought to restore the
microbial balance in the intestine.
Proteins: Essential constituents of all cells. Composed of carbon, hydrogen, oxygen, nitrogen phosphorus and sulphur.
Quorn: see mycoprotein
Rancidity: A chemical change in fats caused by oxidation or hydrolysis. It causes ‘off’ flavours to
Retrogradation (of starch): the opposite of gelatinisation. The starch undergoes a colloidal
change and contracts due to the loss of water. Stabilizers are used in processed foods to
Saturated solutions: A solution that has absorbed as much of a solute as possible at a given temperature. E.g. sugar in water
Sol: the liquid stage of a colloid. E.g.gelatin when cooled a sol become a gel.
Solution: a homogeneous mixture of two phases – the solute and the solvent.
Stabilisers: Substances which absorb water and are often used as thickening agents or to keep an emulsion stable.
Starch: A long chain polysaccharide composed from units of glucose.
Suspension: mixture with two phases solvent and solute that eventually separates.
Syneresis: Refers to overcooked eggs custard, when the proteins shrink as they coagulate and
squeezes out watery liquid ( Seen as holes in the baked custard). Also degrading of a set white sauce as it shrinks.
Viscosity: The thickness of a liquid or a mixture related to flow, such as a sauce.
Xanthan gum: Polysaccharide produced by bacterial fermentation and used as a thickening
agent to form gels and increase viscosity. Used to replace gluten in gluten free flour to achieve acceptable baked products.
Yeast: Microbe and biological raising agent. Bakers yeast has thetechnical name, Saccharomyces Cerevisciae. A source of vitamin B.Ferments to produce carbon dioxide if it has food, moisture, warmth and time.
Zylitol: sugar-free sweetener