1th INTERNATIONAL CONFERENCE ON ADVANCES IN ENGINEERING SCIENCES: THAILAND 2017, Phuket, Thailand, 3 - 05 July 2017, pp.34-40
THE FATE OF IMPURITIES IN SOME LIQUID FOOD RAW MATERIALS
*Ali E Bodur
Canakkale Onsekizmart University Biga Vocational School
Impurity, spirits, vegetable oil, milk
*Phone: 0 286 316 28 78
Fax: 0 286 316 37 33
Impurities are substances that are found in the natural structure of the food or occured during processing except contaminants. They are also undesirable substances. While a substance may be pure for a purpose, it may be impure for another purpose. With proper manipulation, impurities can be reduced to acceptable limits, but the closer the absolute purity is an ideal that can never be approached. The important thing is whether a substance is pure enough or not. It is vital to have criteria to determine the degree of purity in the final product.
Raw milk, crude plant oil and crude spirit are raw liquid foodstuffs that are specially processed to remove impurities. The removal of impurities from these raw materials is traditionally expressed in different terms. Removal of impurities from raw milk, crude vegetable oil and crude spirit are expressed as clarification, refining and rectification respectively. The main impurities in raw milk are somatic cells, bacterial deposits, blood and milk protein clots. Since these elements are denser than milk, they are separated by equipment called a clarifier which operates on a centrifugal basis. The main impurities in crude spirit are fusel oils, esters, aldehydes and ketones. Since the boiling points of them are different, these impurities are removed by equipment called rectifier which operates according to the destillation principle. The main impurities present in crude vegetable oil are free fatty acids, mucilage, phospholipids, various coloring matters and various volatile fatty acid degredation products such as aldehydes and ketones. Since these impurities have different properties, refinement involves some physical and chemical processes.
Crude vegetable oil and crude sipirit can not be consumed without refining and rectification respectively. Clarification can not be used in place of heat treatments such as pasteurization and sterilization because it can not make full bacterial separation. What are the fates of the impurities separated by these processes? The impurities are small amount but they cause significant quantities of waste especially with chemical processes. In this study, impurities and methods of removing them will be explained, and then the possible methods can be used to reduce or prevent them from disposal. Finally evaluation opportunities of these substances will be explained.