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Several pilot-scale trials reported in this paper, using palm stearin-rice bran oil (PS-RBO) blends, obviously did not contain trans FA (TFA), whereas the commercial products were found to contain 18-27% TFA. The effects of processing conditions such as rate of agitation, crystallization temperature, and composition of the blends on the crystal structure of shortenings were studied. The products were evaluated for their physicochemical characteristics using DSC, X-ray diffraction (XRD), HPLC, and and FTIR techniques. The formulation containing 50% PS and 50% RBO showed melting and cooling characteristics similar to those of hydrogenated commercial "vanaspati" samples. Analysis of the FA composition revealed that the formulated shortenings contained 15-19% C 18:2 PUFA. Tocopherol and tocotrienol contents of the experimental shortenings were in the range of 850-1000 ppm with oryzanol content up to 0.6%. XRD studies demonstrated that the crystal form in the shortenings was predominantly the most stable β′ form, and there was less of the undesirable β form.

Crude palm oil (CPO) is the richest natural source of carotenes that are destroyed in the conventional processing. There is a growing demand for nutritional products containing bioactive constituents externally fortified or preserved through modified process. A commercially viable process for the production of red palm olein (RPOn) rich in carotenes, tocols and sterols has been developed at pilot scale. The process developed involved neutralization of CPO followed by crystallization at controlled rate of cooling and deodorization of the resultant neutralized and winterized palm olein (WPOn) under controlled conditions of temperature and high vacuum. Analytical data related to micronutrients at each process step was monitored. The RPOn thus produced had not more than 0.25% of free fatty acids (FFA) and it retained more than 80% of the carotenes, about 85% of tocols and 65% of sterols originally present in the CPO. The physico-chemical characteristics of RPOn revealed that it is nutritionally of superior quality compared to that of the commercial refined bleached deodorized (RBD) palm olein currently available in the market. The carotenes, tocols and sterols profile of RPOn by HPLC showed that they were retained in their natural forms.

Fat blends, formulated by mixing refined, bleached and deodorised (RBD) palm oil (PO) or RBD palm stearin (PS) with RBD rice bran oil (RBO) in various ratios were subjected to chemical interesterification (CIE) at pilot scale using sodium methoxide (NaOMe) as catalyst. The resultant interesterified fat was processed through a margarine crystalliser under optimised conditions. The blends before and after CIE were investigated for triacylglycerol (TAG) composition, solid fat content (SFC) and melting characteristics, polymorphic form, fatty acid composition (FAC), bioactive (tocols, sterols, oryzanol) constituents and trans fatty acids (TFA). CIE was found to be very effective in terms of rearrangement of fatty acids (FAs) among TAGs and consequent changes in the physical characteristics. The SFC of the interesterified PS ⁄ RBO blends decreased significantly (P £ 0.05) when compared with those of PO ⁄ RBO blends. The interesterified binary blends with 50-60% PS and 40-50% RBO, and 70-80% PO and 20-30% RBO had SFC curves in the range of all-purpose type shortenings. CIE facilitated the formation of b¢ polymorphic forms. FAC of shortenings prepared using the optimised blends contained 15-20% C 18:2 polyunsaturated fatty acid (PUFA) and no TFA. Total tocol, sterol and oryzanol content of zero trans shortenings were 650-1145, 408-17 583 and 1309-14 430 ppm. CIE using NaOMe did not affect the bioactive constituents significantly (P £ 0.05).

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Seven regions of coconut endosperm, comprising four (inner, middle, outer and testa) from the region adjacent to the water cavity to the testa; and three transverse regions from top to bottom, were analyzed for moisture, fat, protein, non‐protein nitrogen, soluble sugars, reducing sugars, fiber, total ash and acid insoluble ash. The fat extracted from these regions was analyzed for fatty acid composition and chemical characteristics. A marked gradient in the concentration of major constituents was observed across the endosperm, from the inner region enclosing the water cavity through middle and outer regions and testa, the gradation being more striking for moisture fat and soluble sugars. Fatty acids 6:0 to 12:0 were concentrated in the inner regions, and their contents decreased toward the outer regions with a corresponding increase in the higher acids and unsaturated fatty acids. The chemical characteristics of the fat (Reichert value, Polenske value, iodine value and saponification value) from these regions were found to be compatible with the fatty acid profile. The distribution of the constituents in the transverse regions of the coconut endosperm was fairly uniform.

Coconut is the largest oilseed. In the present investigation, various lipid classes, such as triacylglycerol, free fatty acid, diacylglycero], and their fatty acid compositions were determined from three regions of germinating coconut at three stages of germination. In this process, triacylglycerol was hydrolyzed and resynthesized in the haustorium tissue. Cooperative participation of various tissues, such as endosperm, haustorium, and embryo, was therefore involved in the process of germination of coconut. 72, 647-651 (1995). JAOCS