Food production and effects on nutrients

• nutrient profile


  the different types and quantities of nutrients that a specific food contains.
• nutrient profile can be affected by:

  -the environment in which they were grown or reared in: e.g. if the soil contains lots of minerals, water and micro-organisms so crop can grow healthy and nutrient profile will be dense and varied.
• Can be affected by:

  -length of time they are stored after harvest or slaughter: natural processes break down the composition which results in destruction of food. e.g. fish are kept in ice when killed to slow down deterioration and maintain nutrient profile.
• can be affected by:

  -the variety/species of plant or animals: the nutrient density will naturally vary due to variety and the species. e.g. different types of apples.
• leaching 


  the loss of a nutrient from a food by it dissolving in the water it is cooked in.
• denaturation of protein 


  the bonds are disturbed by heat, whisking or the PH level which results in the unravelling and reshaping of the protein molecules.
• after denaturation happens coagulation takes place which is

  where the unravelled denatured protein molecules occupy a greater amount of space and start to interact with other denatured protein molecules nearby which forms solid gel textures.
• when heated, fats melt gradually to oils 


  this is because molecules are a mixture of different sizes and types of fatty acids, each with a different melting point. When heating continues it will reach smoke point (around 230 degrees for veg oil) then the oil will produce flames causing domestic fires.
• at smoke point some fatty acids break away from the triglyceride and become free fatty acids which causes oxidation reaction.

  When oil is repeatedly reheated the fat molecules decompose as number of fatty acids is increasing which lowers temperature of smoke point and makes it more likely for oil to become rancid.
• rancid fats


  -have an unpleasant off smell

  -it increases risk of developing cancers and heart disease.

  -this will happen more with oils that contain high levels of polyunsaturated fatty acids such as sunflower oil compared to monounsaturated fatty acids such as olive oil.
• gelatinisation


  when starch is heated to 60 degrees in water, the starch granules absorb the water and begin to swell. When starch molecules reach 80 degrees some starch granules start to burst which starts to make liquid thicker. Then at 100 degrees gelatinisation is complete and the liquid is thickened.