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The effect of oryzanol, tocopherols and tocotrienols (tocols) and sterols individually and as combinations of two were analyzed for DPPH radical scavenging activity and antioxidant activity. Oryzanol, tocols and sterols were isolated by using column chromatography and then added at known concentrations in stripped RBO. The results showed that tocol added samples are more stable than with oryzanol and sterol as individual additions. Among them T (sample having 0.04% tocols) is more stable than T (sample having 0.08% tocols). Comparing T and T with control oil, T had a peroxide value almost similar to control oil (T, 5.68 mequiv/kg : control oil, 5.52 mequiv/kg) showing the antioxidant activity of tocols even in the absence of other micronutrients. The diene value of both T (4.27) and T (4.03) is lower than control oil (6.14). While analyzing combinations, prevention of oxidation was significantly better for oryzanol and tocols combinations, OT had a peroxide value of 10.57 mequiv/kg, OT, 10.42 mequiv/kg when compared to the control sample (52.25 mequiv/kg). Similarly the diene value 5.86 (OT) and 7.1 (OT), the p-anisidine value 53.8 and 63 for OT and OT, respectively. The DPPH activity of samples T (0.08% tocols) and OT (sample having 0.8% oryzanol + 0.08% tocols) had a lower IC on the initial day and the IC was lowest for T (0.04% tocols) and OT (sample having 1.6% oryzanol + 0.04% tocols) on the final day. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Sea buckthorn berries from Hippophae rhamnoides, H. tibetana, and H. salicifolia were collected from the cold deserts of the Himalayas (Lahaul, Ladakh, and Spiti; India) and characterized in terms of the FA, carotenoid, tocopherol, and tocotrienol composition in their pulp oil. These varied from species to species. Total carotenoids ranged from 692 to 3420 mg/kg in pulp oils of fresh berries, and total tocols, from 666 to 1788 mg/kg. Hippophae salicifolia berries contained substantially lower amounts of pulp oil, with lower levels of carotenoids and tocopherols. There was little difference in the proportion of individual tocols in pulp among the three species. α-Tocopherol alone constituted 40-60% of total pulp tocols in berries. Pulp oils had palmitoleic acid (32-53%) as the most abundant FA followed by palmitic (25-35%), oleic (8-26%), linoleic (5-16%), and linolenic (0.6-2.6%) acids, with the highest deviation observed in the proportion of palmitoleic acid in these berries. Hippophae rhamnoides and H. tibetana contained the highest amount of the lipophilic carotenoids and tocols. Hippophae salicifolia berries had higher amounts of lipophobic constituents such as vitamin C and flavonols. [ABSTRACT FROM AUTHOR]

A new process for the physical refining of rice bran oil through combined degumming and dewaxing was developed on a laboratory scale and then demonstrated on a commercial scale. The simultaneous degumming and dewaxing of the crude oil with a solution of water and CaCl2, followed by crystallization at a low temperature (20°C), facilitated precipitation of the hydratable and nonhydratable phosphatides along with the wax, which enabled its separation and reduction to a greater extent. Bleaching and subsequent winterization (20°C) of this oil further reduced the phosphorus content to less than 5 ppm. Thus, these pretreatment steps enabled the physically refined rice bran oil to meet commercially acceptable levels for color, FFA content, and cloud point values (10-12 Lovibond units in a 1-in. cell, <0.25%, and 4-5°C, respectively) with very low neutral oil loss; this has not been observed hitherto. Rice bran oil is known for its high levels of bioactive phytochemicals, such as oryzanol, tocols, and sterols. The process reported here could retain more than 80% of these micronutrients in the end product. [ABSTRACT FROM AUTHOR]

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-I 9% C18:2 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. [ABSTRACT FROM AUTHOR]

Development of free fatty acids (FFA) and subsequent deterioration of palm oil quality can be attributed to lipase, an active hydrolytic enzyme present in the mesocarp of oil palm fruit. A histochemical method was used to localize this enzyme in the mesocarp. FFA released from endogenous glycerides were precipitated as lead salt. The deposits were located on the membranes of oil bodies. Enzymatic activity in the mesocarp was also studied under different conditions of fruit storage: ambient temperature, freezing, etc. The enzyme was active after freezing but less active under ambient conditions of fruit storage. Investigations on fruit development indicated that the enzyme activity started appearing between 16-20 weeks after anthesis (WAA) which synchronized with the beginnning of lipid formation. These histochemical studies were supported wity biochemical data on FFA. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The mechanism of mobilization and utilization of lipids by the developing seedling and the involvement of different tissues in this process was examined in germinating coconut. The endosperm (lipid reserve) and haustorium (spongy tissue developed during germination) were separated from germinating coconuts at intervals of two weeks up to week 22, and assayed for lipase, isocitrate lyase, malate synthase, and catalase, as well as for lipids and sugars. Except for lipase, activities of all the other enzymes were absent in the endosperm during the entire period of germination. However, these enzymes were found to be activated after the tenth week after germination and plateaued at week 16. Induction of these enzymes indicated the operation of the glyoxylate cycle in the haustorial tissue. Glyoxysomes also were observed in the haustorium. The haustorium was shown to absorb triacylglycerol and free fatty acids from endosperm for subsequent conversion to sugars in this tissue. Haustorium therefore is a biochemically active tissue and is the site of operation of the glyoxylate cycle in germinating coconut. [ABSTRACT FROM AUTHOR]

Coconut is the largest oilseed. In the present investigation, various lipid classes, such as triacylglycerol, free fatty acid, diacylglycerol, 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. [ABSTRACT FROM AUTHOR]

The pattern of accumulation of triacylglycerols, their fatty acid compositions and the positional distribution of the fatty acids at the sn-2- and sn-1,3-positions of the triacylglycerol molecules at progressive stages of oil palm fruit development were determined. There was an exponential rate of increase of triacylglycerols and their fatty acids toward the end of fruit development. The fatty acid composition of the triacylglycerols in the early stages of development, prior to active accumulation, was more or less similar, but differed appreciably from the later stages, and the transition of fatty acid composition toward that of normal palm oil occurred at around 16 wk after anthesis (WAA) and stabilized at 20 WAA. All fatty acids increased in terms of absolute quantity. There was an overall consistency in fatty acid positional distribution, irrespective of development stage. More saturated fatty acids were found to be esterified at the sn-1,3-positions and more unsaturated fatty acids at the sn-2-position of triacylglycerol. Higher rate of incorporation of 16:0 at the 1,3-positions during the active phase of triacylglycerol synthesis was observed, while 18:1 acid exhibited a reverse trend. [ABSTRACT FROM AUTHOR]

A novel method has been developed for the removal of the thin, dark-brown skin, called testa, from the palm kernel of the oil palm ( Elaeis guineensis) by chemical treatment. Studies carried out for this purpose included physical or mechanical means, dry or wet heat, solvents and other chemicals. Of the procedures tried, treatment with hydrochloric acid (HCl) resulted in complete removal of the testa, producing a pearl-white palm kernel. All other treatments were found to be ineffective. Based on our laboratory studies, semi-large-scale trials were made with 4N HCl for continuous dehulling of palm kernel in an abrasive peeling machine for the preparation of superiorgrade kernel flour and oil. [ABSTRACT FROM AUTHOR]

During palm oil extraction, oil loss occurs mainly at three stages of processing, namely sterilization, pressing and clarification. Samples from a semi-commercial palm oil mill were analyzed for their lipid composition (triacylglycerol, diacylglycerol, monoacylglycerol, free fatty acid, phospholipid and glycolipid contents and fatty acid compositions of these lipid classes) and compared with the end product, viz., raw palm oil. The results indicate significant variations between the samples with respect to oil quality and lipid profile. Data relating to the lipid classes showed that sterilizer condensate had the highest levels of free fatty acids (24%), followed by press fiber (12.5%) and sludge effluent (10.9%), as compared to raw oil (1.5%). Diacylglycerol and monoacylglycerol contents were also markedly higher for these streams. Press fiber was characterized by extremely high proportions of phospholipids and glycolipids. Distribution of fatty acids (16:0, 18:1, 18:2 and 18:3) also varied among lipid classes of the process streams, particularly between polar lipids. This paper discusses the compositional aspects of lipids relating to quality of oils of the palm oil mill streams. [ABSTRACT FROM AUTHOR]

Lipid classes and fatty acids were analyzed in expeller and rotary extracted coconut oils and corresponding solvent extracted cake oils. Triacylglycerols (84.0 to 93.1%); 1,2 diacylglycerols (1.5 to 5.1%); 1,3 diacylglycerols (1.2 to 2.1%); monoacylglycerols (1.0 to 7.0%); free fatty acids (1.0 to 2.6%); phospholipids (0.03 to 0.4%) and glycolipids (0.2 to 0.35%) were present in these oils. Fatty acid composition of triacylglycerols, phospholipids and glycolipids resembled each other and differed from those of 1,2 and 1,3 diacylglycerols which in turn were similar. [ABSTRACT FROM AUTHOR]