Deodorization is the most important step in the oil refining process due to the quality parameters required for packing and human consumption. Deodorization helps eliminate odoriferous compounds along with free fatty acids by steam distillation. Additionally oils are heat bleached to attain the required product quality in terms of colour parameters.

Deodorization is a multi stage process which includes the deaeration, regenerative heating, final heating, stripping, deodorization and regenerative cooling of oil.

Bleached oil is heated and fed to the deaerator to remove air and moisture to avoid oxidation of oil during deodorization while processing at high temperatures. Deaerated oil is heated regeneratively by the outgoing deodorized oil in the economizer. This step offers maximum heat recovery. Pre-heated oil is further heated to required deodorization temperature by a high-temperature medium or high pressure steam in the final heater. It is then sent to the stripper followed by retention to remove free fatty acids and volatile components which are responsible for the odor. Optimum deodorization time, vacuum and temperature are necessary for an efficient deodorization process.

Vacuum reduces the boiling point of FFAs and odoriferous compounds and also reduces the working temperature of the deodorizer and also minimizes steam consumption.

This technique is used to extract tocopherol rich fraction from fatty acid distillates obtained during deacidification of vegetable oils. Scrubbing takes place at two different temperature zones to obtain fatty acid rich and tocopherol rich fractions that can be used in the oleochemicals and pharmaceutical industries after further processing.

With climatic conditions and environmental and regulatory norms at the forefront, Kumar offers plants with various vacuum systems to optimize the edible oil refining process and obtain good quality refined oil with an extended shelf life.

• Vacuum systems with direct condensers comprise ejectors, boosters and direct mixing condensers. They are the most used vacuum system used in edible oil refineries and oleochemicals because of their robust and maintenance free operation. The only limitation is the odor resulting from the contaminated water cooling tower.
• Vacuum systems with surface condensers comprise ejectors and boosters with surface condensers. The advantage to this system is the separate process and cooling medium.
• Closed loop chilled water vacuum systems resolve the odor issue and stabilize vacuum parameters due to constant temperature of the chilled water sent to the condensers. In regions with inexpensive electricity, a closed loop chilled water vacuum system is the most effective option as compared to traditional vacuum systems.
• Ice condensation vacuum systems are the best choice for higher capacity plants due to their low operating cost. They also do not have odor problems and therefore no environmental concerns. They deliver quality products due to stable and optimum vacuum. Process steam is condensed and converted into ice. Vacuum steam is used to effectively melt the ice layer.

The deodorizing process is used primarily for soybean, sunflower, rapeseed, palm and palm kernel oil.