Processing of fats and oils

The edible oil consumer requires that the marketed product should be of acceptable quality irrespective of whether the product is a virgin or crude oil, for example olive oil or premier jus tallow, or a fully refined oil. 

The aspects of importance in edible oil products are eating quality, appearance, oxidative or shelf-life stability and consistency of quality. By eating quality it is meant that the product should not be harmful and that its flavour and odour should be acceptable to the consumer. These aspects must be achieved by the processor as efficiently as possible. 

The impurities with which the processor has to contend are as follows  

Naturally occurring components of the oil/raw material such as pigments, phosphatides, trace metals. 

Contaminants resulting from agronomy and harvesting such as trash or dockage, dirt and chemicals, toxic weeds (List and Spencer, 1979). 

Despite these precautions, small amounts of volatile sulfur compounds are formed. However, they are removed during the refining process. Irrespective of technical achievements in rape-seed production and processing, the selection and breeding of rapeseed double zero cultivars is being continued. 

Rapeseed Canola) oil is used as an edible oil. It is susceptible to autoxidation because of its relatively high content of linolenic acid. It is saturated by hyrogenation to a melting point of 32-34 °C and, with its stability and melting properties, resembles coconut oil. 

Turnip rape oil has practically the same composition as the B. napus oil. It may contain at most 5% of erucic acid, because this can damage the heart muscle in high concentrations. 

Sesame Oil is obtained from an ancient oilseed crop (Sesamum indicum, L.), which is widely cultivated in India, China, Burma and east Africa (cf. Table 14.0). In its refined form the oil is nearly crystal clear and has a good shelf life. In addition to a considerable amount of tocopherols, it contains another phenolic antioxidant, sesamol, which is derived from hydrolysis of sesamolin (Fig. 14.3). 

Sesame oil can be readily identified with great reliability (cf. Table 14.21). Therefore, in some countries, blending this oil into margarine is required by law in order to identify the product as margarine. 

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Monoglyceride (MG) is one of the most important emulsifiers in food and pharmaceutical industries [280], MG is industrially produced by trans-esterification of fats and oils at high temperature with alkaline catalyst. The synthesis of MG by hydrolysis or glycerolysis of triglyceride (TG) with immobilized lipase attracted attention recently, because it has mild reaction conditions and avoids formation of side products. Silica and celite are often used as immobilization carriers [281], But the immobilized lipase particles are difficult to reuse due to adsorption of glycerol on this carriers [282], PVA/chitosan composite membrane reactor can be used for enzymatic processing of fats and oils. The immobilized activity of lipase was 2.64 IU/cm2 with a recovery of 24%. The membrane reactor was used in a two-phase system reaction to synthesize monoglyceride (MG) by hydrolysis of palm oil, which was reused for at least nine batches with yield of 32-50%. 

Homberg,V. (1974) Alteration of sterols by industrial processing of fats and oils, I Influence of refining conditions on the sterol content and sterol composition. Fette Seif. Anstrichm., 76(10), 433 135. 

S. Sefa Koseoglu Extraction and Rehning Program, A Division of Eiltration and Membrane World LLC, College Station, Texas, Membrane Processing of Fats and Oils. 

Use of Enzymes Lipases are widely used in the processing of fats and oils as catalysts of a number of important lipid reactions, such as hydrolysis, esterification, and transesterification reactions (174). There are a wide number of lipases obtained from different sources, which are available commercially in their free/ crude or immobilized form. However, enzymes with a higher tolerance of pressure would be welcomed, and more research is needed to hopefully develop such enzymes (i.e., genetic engineering or marine sources of the deep ocean). 

Carlson, K. Recent developments and trends in processing of fats and oils. Inform 2006, 17,... 

Weiss, T.J. Basic processing of fats and oils. Pood Oils and Their Uses, Second ed. A V I Publishing Westport, CT, 1983 pp. 96-97. 

Tombs MP (1995) Enzymes in the processing of fats and oils. In Tucker GA, Woods LFJ (eds). 

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