Main constituents of rapeseed lecithin

Commercial rapeseed lecithin has been analyzed after separation by silicic acid column chromatography. Besides neutral oil (40%), four major constituents have been found, viz., phosphatidyl ethanolamine (18%), phosphatidyl inositol (8%), phosphatidyl choline (16%) and sterol glycosides (8%). Among the minor fractions lysophosphatidyl ethanolamine accounts for about 2%. The phosphatides are characterized by low erucic acid content and the major fatty acids are palmitic, oleic and linoleic acids.     

The production of Chinese rapeseed protein isolates by membrane processing

A membrane-based process was developed for the production of Chinese rapeseed protein isolates, which consisted of alkaline extraction of protein at pH 12.0 from CH₂OH/NH₃/H₂O-hexane-extracted Chinese rapeseed meal, isoelectric precipitation at pH 6.5, ultrafiltration followed by diafiltration to concentrate the remaining soluble protein, and freeze-drying. No chemical treatment was required for the removal of phytates from the protein. Three products were obtained with high protein recovery: precipitated and soluble protein isolates, each containing 90 to 100% protein, suitable for animal feed. The two protein isolates were low in phytates, light in color and bland in taste. Chinese rapeseed protein was easier and more economical to treat than canola protein due to the shift of pH for isoelectric precipitation and the elimination of the need for further phytate reduction.     

Modern processing of rapeseed

The various processing steps for rapeseed into finished oil and meal products have been reviewed. Particular attention has been given to recent developments, such as the inclusion of an extruder step in oil extraction, an aqueous enzymatic process to separate flakes into oil, flour and molasses, the TOP total degumming process, and the new Centri-Ad process to eliminate small quantities of impurities (dissolved or emulsified) from large volumes of liquid by a continuous adsorption-centrifugation technique.     

Effects of processing on the functional properties of canola/rapeseed protein

Canola rapeseed is a major oilseed in Canada, Europe and Japan. Recently, Generally Recognized As Safe (GRAS) status was granted to low erucic acid rapeseed oil for use in the U.S. market. Commercial oil extraction of the seed results in a meal that contains 44% protein and which has been subjected to considerable heat. The meal is presently utilized as livestock feed supplement. A number of processes for the preparation of protein concentrates and isolates from canola/rapeseeds and meal have been proposed, although none have proven commercially viable. In addition to protein concentration, a successful process must reduce the levels of glucosinolates, phenolics, phytates and fiber. These antinutrients present a barrier to the use of canola/rapeseed protein materials in foods. Processes to produce protein concentrates have included water extraction of undesirable compounds from heat denatured, dehulled seed followed by solvent extraction for oil recovery and the isopropanol washing of dehulled, defatted flours. Isolates have been prepared by traditional alkaline extraction, and by acid or water extractions followed by isoelectric, heat or polyelectrolyte precipitation of the protein. Isolates have been chemically and enzymatically modified to improve fooduse properties. In this paper, the effects of various processing methods on the functional properties of solubility, color and flavor of canola protein products are reviewed. Presented at the 78th American Oil Chemists' Society Annual Meeting, May 17–21, 1987, New Orleans, LA.     

Sulfur compounds affecting processing of rapeseed

A characteristic feature of cruciferous oilseeds is a high level of sulfur compounds as sulfur-containing amino acids and glucosinolates which determine the nutritional value of rapeseed meal and affect processing factors in oil mills. During rapeseed processing, products of glucosinolate splitting are liberated and attack metal and, as a result, a specific sulfur corrosion of oil mill equipment develops. The most exposed are cooker, toaster and transporters of wet meal. The results of industrial investigation of sulfur corrosion are described and the sensitivity to corrosion of several construction steels during rapeseed processing is considered. A high content of sulfur-containing compounds in starting oil significantly depressed the nickel catalyst activity and influenced the kinetics of rapeseed oil hydrogenation. Removal of these compounds by refining and its influence on the rate of oil hydrogenation are discussed.     

Chemical constituents, in vitro protein digestibility, and presence of antinutritional substances in amaranth grains

The chemical composition, content of antinutritional factors, and the in vitro protein digestibility of grains of the pseudo-cereal Amaranthus were analyzed. The plants were grown in Brazil (without fertilizer), Puerto Rico (100 kg N/ha), and California (200 kg N/ha). The seed analysis gave the following values (%DM): 14.4 - 16.9 protein (N X 6.25), 4.8 - 6.8 fat, 2.5 - 3.9 ash, and 2.3 - 2.9 crude fiber. The trypsin inhibitors, phenolics and saponine contents were low, and the phytohemagglutinin activity, fairly low. The in vitro protein digestibility was 61 - 76%. Digestibility was not correlated to the analyzed proximal composition nor to the antinutritional factors. The grain composition indicates a food value equivalent to that of conventional food grains.     

Solubility of rapeseed protein in aqueous solutions

The solubility of the protein of the dehulled and defatted ‘Tower’ variety of rapeseed in aqueous solutions was determined at temperatures of 25, 35, 45, and 55 C in the pH range of 1–13. It was found that the points of minimum solubility occur at pH values of 4.5, 4.8, 7.0, and 7.2, respectively, for the above four temperatures. No color change of the meal was observed at or near the minimum solubility point. The aqueous solutions were prepared at the selected pH values by using either NaOH or H₂SO₄.     

Production and characterization of an extensive rapeseed protein hydrolysate

Rapeseed protein isolate has been used as starting material for the generation of an extensive protein hydrolysate. Protein hydrolysis was produced by using sequentially an endopeptidase (Alcalase) and an exopeptidase (Flavourzyme). The final hydrolysate has a 60% degree of hydrolysis and was completely soluble between pH values 2.5 and 7. Molecular weight profile of the protein hydrolysate was characterized by gel filtration chromatography. A reduction in protein size was observed during the hydrolysis process with accumulation of small peptides and free amino acids after Flavourzyme digestion. Amino acid composition of fractions with different molecular weights of the final hydrolysate was analyzed. Some of these fractions, enriched or poor in certain amino acids, could be used for supplementation or treatment of determined clinical syndromes.     

Use of esterified rapeseed oil as plasticizer in plastics processing

Until today rape methyl ester (RME) offered as Biodiesel is mainly used as fuel in diesel engines, where it is therefore in hard competition with conventional diesel fuel. Economical constraints arising therefrom, but also the possibility to utilize this valuable raw material more efficiently, were the reasons for considerations about its use in the plastic web industry. The plasticizers used in PVC coating in general, but chlorinated paraffins in particular are criticized because of their environmentally harmful action (waste water, air pollution). Thus, with regard to costs and environmental reasons, producers of plastic webs are greatly interested in alternatives to the common plasticizers. Therefore, investigations concerning the use of RMEs in spread and calender coating with PVC were carried out in laboratory and industrial scales within the framework of a project supported by the Saxon Ministry of Enviroment and Agriculture. The experimental results show that partial substitution of phthalic acid ester plasticizers (max. 50%) or plasticizers based on chlorinated paraffin by RMEs is possible. The demands with respect to processability (e.g. compatibility, gelling behaviour, volatility) and quality of the final products (e.g. strength, migration, and temperature resistance, surface quality) are essentially met.     

Chemical constituents of Solanum coagulans and their antimicrobial activities

The present study aimed at determining the chemical constituents of Solanum coagulans and their antimicrobial activities. The compounds were isolated by various chromatographic techniques and their structures were elucidated on the basis of extensive spectroscopic analysis, chemical methods, and comparison with reported spectroscopic data. One new phenolic glycoside, methyl salicylate 2-O-β-D-glucopyranosyl-（1→2）-β-D-glucopyranoside（1）, together with 12 known compounds（2–13）, were isolated from the aerial parts of Solanum coagulans. Compound 1 was a new phenolic glycoside, and 2–6 were isolated from Solanum genus for the first time. The antimicrobial activities of the isolated compounds were also evaluated. Compound 7 showed remarkable antifungal activity against T. mentagrophytes, M. gypseum and E. floccosum with MIC values being 3.13, 1.56 and 3.13 μg·m L^-1, respectively.     

Minor constituents of vegetable oils during industrial processing

We report the effects of individual steps of industrial refining, carried out in Brazil, on the alteration of selected minor constituents of oils, such as corn, soybean, and rapeseed oils. Total sterols, determined by capillary gas chromatography (GC), decreased by 18–36% in the fully refined oils, compared with the crude oils. The total steradienes, dehydration products of sterols, were determinedvia a simple clean-up on a short silica gel column, followed by high-performance liquid chromatography (HPLC) with ultraviolet detection. The level of steradienes, normally not present in crude oils, increased after each refining step, especially after deodorization. Thus, the content of steradienes increased after deodorization by about 15- to 20-fold in corn and soybean oils, and by about 2-fold in rapeseed oil. The total steryl esters were also determinedvia clean-up on a short silica gel column, followed by HPLC with evaporative light scattering mass detection. A minor decrease in the level of steryl esters was observed after complete refining. The individual tocopherols and tocotrienols were determined by HPLC with a fluorescence detector. The level of total tocopherols and tocotrienols decreased by about 2-fold after complete refining of corn oil and by about 1.5-fold in soybean and rapeseed oils. In all three cases, maximum reduction of tocopherols was observed after the deodorization step. The level of polymeric glycerides, determinedvia clean-up on a short silica gel column followed by size-exclusion HPLC, increased to some extent (0.4–1%) during refining. The level oftrans fatty acids, determined by capillary GC, also increased to a substantial extent (1–4%) after refining. Part of doctoral thesis of Roseli Ap. Ferrari to be submitted to Faculdade de Engenharia de Alimentos, Universidade de Campinas, Campinas, Brazil.     

恩施地区野棉花化学成分及其抗肿瘤活性

采用硅胶、SephadexLH-20、制备液相等色谱方法对恩施地区银莲花属植物野棉花的乙醇(体积分数为70%)提取液进行分离纯化,运用NMR、MS等方法进行结构鉴定,并考察了化合物的抗肿瘤活性。结果显示,得到了10个化合物,分别为络石苷元(Ⅰ)、牛蒡子苷元(Ⅱ)、绿原酸(Ⅲ)、紫云英苷(Ⅳ)、异槲皮素(Ⅴ)、银椴苷(Ⅵ)、络石苷(Ⅶ)、牛蒡子苷(Ⅷ)、水杨苷(Ⅸ)、薯蓣皂苷(Ⅹ)。其中,化合物Ⅰ～Ⅱ、Ⅵ～Ⅶ、Ⅸ是首次从银莲花属中分离得到,化合物Ⅰ～Ⅶ、Ⅸ、Ⅹ是首次从野棉花中分离得到。MTT(四唑盐比色法)测试结果显示,化合物Ⅱ、Ⅷ、Ⅸ、Ⅹ在100μmol/L时对宫颈癌细胞(HeLa)的抑制率分别为10.5%、7.0%、0.5%及88.0%,其中化合物Ⅹ的活性最好,高于阳性对照品顺铂的抑制率(80.5%)。     

Chemical and physical effects of processing fats and oils

Soybean oil is processed for a variety of food uses, salad/cooking oil, margarine and shortening. Crude soybean oil is composed mainly of triglycerides but also contains measurable amounts of minor constituents that may have beneficial or detrimental effects on oil characteristics. The nature of these minor constituents, the role they play in oil stability or deterioration and their fate during processing are subjects of this review. Iodine value, fatty acid composition, solid fat index and congeal point are chemical and physical characteristics of oil that are affected by the hydrogenation process. Techniques and effects of degumming, alkali refining, bleaching, hydrogenation, winterization and deodorization are discussed. Utilization or disposal of by-products or wastes from each processing step is reviewed. Presented at Northeast Section, AOCS, Symposium, Newark, N.J., November 5–6, 1979.     

新木姜子属植物化学成分及其生物活性研究进展

本文对新木姜子属植物的化学成份和生理活性作了全面系统的综述，为该属植物的开发利用提供了科学的依据。     

Partially hydrolyzed rapeseed protein isolates with improved functional properties

Limited rapeseed protein hydrolysates ranging from 3.1 to 7.7% hydrolysis were produced from isoelectric-precipitated protein isolate. Water absorption, oil absorption, whippability, foam capacity and stability, emulsifying activity, and emulsion stability of the hydrolysates were determined. All protein hydrolysates showed better functional properties than the original protein isolate. Foam and emulsion stability decreased as the degree of hydrolysis increased. The hydrolysate with the lowest degree of hydrolysis showed the best functional properties. These improved functional properties make rapeseed protein hydrolysates a useful product to be used in foods such as breads, cakes, ice creams, meat products, desserts, and salad dressings.     

Integrated processing of peanut for the separation of major constituents

Summary Bench-scale experiments were carried out on the processing of peanut by a new method. The decuticled kernels were pasted, and the paste was subjected to the Skipin process to recover approximately 30% oil; the residual paste was made into a dispersion at 10.0 pH and clarified to get a carbohydrate meal (15.7% moisture-free); the clarified dispersion was centrifuged to obtain another 12% fat and the remaining dispersion was acidified to get the protein (21.9% moisture-free). Fifteen batches of 100-1b. (45.4 kg.) each have been processed, and the reproducibility of the yields has been ascertained. The scope for increasing the oil yield and for improving protein quality is discussed.     

Heat-induced gelation of rapeseed proteins: Effect of protein interaction and acetylation

The gel-forming abilities of a rapeseed protein isolate, composed of 70% globulin (cruciferin) and 30% albumin (napin), and their individual protein components, were investigated. The influence of acetylation upon the gelation properties was also studied. Highest gel strength (measured as shear modulus) of the isolate was obtained at pH values around 9, which is between the isoelectric points of both major proteins. Purified cruciferin gave the highest shear modulus values, with maxima at pH 6 and 8. Weak and poorly stable gels exhibiting strong hysteresis were obtained with isolated napin. Acetylation resulted in a pH shift of the shear modulus maximum of the protein isolate to about 6. The gelation temperature of the acetylated isolate had the highest pH and concentration dependence compared with the other proteins.     

The effect of processing operations on the total sulphur content in rapeseed oil

The technological difficulties due to the presence of sulphur-containing compounds in rapeseed oil lead to the problem of proper hydrogenation under commercial conditions. The effect of refining operations on the total sulphur content of rapeseed oil was studied. Degumming (phosphoric acid treatment) had an insignificant effect on the sulphur content while deacidification (alkali refining) removed about 30% and bleaching with Fuller's earth removed about 50% of the total sulphur in commercial crude oil. Deodorization affected nearly the complete removal of residual sulphur left after the application of treatments mentioned above.