Edible oils purchased in stores are known as "RBD" oils, i.e. oils that have been Refined, Bleached and Deodorized. Processing of edible oils is often broken into the three RBD categories: refining, bleaching and deodorizing. Refining of oils may include neutralization of fatty acids, removal of phospholipids (a compound containing phosphorous), and filtering of the oil. Bleaching removes the oil components that increase the rate of oxidation. When oil is used at high temperatures, for example when pan frying or deep-fat frying, oxidation is accelerated and the oil may develop undesirable characteristics such as off flavour or dark colour quickly. Bleaching allows the oil to be used for a longer period of time before these undesirable characteristics occur. Deodorizing removes all of the unwanted components (vitamins, fatty acids, protein fragments, traces of pesticides and heavy metals, etc.) from the oil, leaving it flavourless and odourless, essentially the same as other oils which are deodorized.
This SOLTEQ® Oil Neutraliser / Washer / Bleacher unit is a lab-scale batch processing vessel capable of carrying out the neutralisation, washing and bleaching processes on small batches of crude edible oils, as part of the edible oil refining process. Removal of free fatty acids (FFA) is done by the neutralisation process, forming a water-soluble soap, subsequently removed by washing, gravity settling and draining. Colour and impurities are removed by mixing the oil with bleaching earth.
This SOLTEQ® Oil Deodorizing Unit is a lab-scale batch processing vessel capable of carrying out the deodorisation process on small batches of edible oils, as part of the edible oil refining process. Free fatty acids, ketone and acetaldehyde traces in edible oils render an unpleasant odour to the oils. Removal of these compounds is achieved by a steam stripping process, under high temperature and high vacuum conditions, where the steam is passed through the heated oil.
This SOLTEQ® Oil Hydrogenation Unit is a lab-scale batch processing vessel capable of carrying out an oil modification process – hydrogenation, on small batches of edible oils, to increase the degree of saturation. By varying the process conditions, unsaturated oils can be ‘hardened’ by reacting with hydrogen gas, in the presence of a nickel catalyst to speed up the rate of reaction, forming saturated fats.