Journal of the American Oil Chemists' Society

Khi sử dụng một hệ thống chất nhũ hóa có thành phần và trọng lượng phân tử đã biết, chúng tôi nhận thấy rằng để nhũ tương chất béo có 15% hàm lượng dầu ổn định với nhiệt độ cần thiết cho quá trình tiệt trùng, các chất nhũ hóa phải đáp ứng những yêu cầu nhất định. Tỷ lệ phần trăm trọng lượng tối thiểu của tổng nhóm ưa dầu (lipophilic) cần đạt 0,29%; tỷ lệ phần trăm trọng lượng tối thiểu của tổng nhóm ưa nước (hydrophilic) cần đạt 0,57%; các nhóm polyoxyethylene trong các chất nhũ hóa chứa nhóm này phải chiếm ít nhất 70% trọng lượng mol của các chất nhũ hóa; tỷ lệ ưa dầu / ưa nước nên vào khoảng 0,5. Hàm lượng tối thiểu của các nhóm ưa dầu và ưa nước được tìm thấy là tổng cộng thêm của các nhóm này trong hệ thống nhũ hóa hoàn chỉnh, bất kể là được cấu thành từ các tác nhân nhũ hóa đơn lẻ hay đa dạng và bất kể có cùng hoặc khác nhóm chức năng. Đối với các chất nhũ hóa được sử dụng, một nhóm acyl dài hơn 12 nguyên tử carbon được xác định là cần thiết để chuẩn bị nhũ tương dầu hạt bông có khả năng ổn định với nhiệt. Khả năng chịu đựng của nhũ tương trước sự phá vỡ do tác động cơ học được thể hiện qua một lượng lớn nhóm ưa dầu, để tỷ lệ ưa dầu/ưa nước đạt 1 hoặc cao hơn.

The object of the present work has been to study those soybean phosphatides which cannot be extracted by means of nonpolar solvents but only be means of mixtures of nonpolar and polar solvents, for instance hexane and ethanol. These phosphatides were fractionated by the countercurrent distribution technique, and the following groups of substances were found: a) carbohydrates with d-inositol in the form of the methyl ether called pinitol; b) a number of nitrogen-containing substances, the nature of which is not as yet fully elucidated but which is perhaps merely decomposition products of proteins; c) a glyceroinositophosphatidic acid which contains equimolar quantities of glycerophosphoric acid and inositolmonophosphoric acid and phosphorus and fatty acids at a ratio of about 1 to 2; d) a high-molecular phosphatide acid; and e) a mixture of the three glycerophosphatides: phosphatidylcholine,-ethanolamine, and-serine.

Biotechnology is the application of single or multicellular organisms and of associated or derived enzyme systems to the production of desirable products. Particular discussion has been made of the derivation of fats and oils from animals, plants and microorganisms. General consideration has been given to methods, primarily plant breeding and agronomic practices for the improvement of the quantity and quality of oil produced by soybean, rapeseed, palm and sunflower. The possible importance of yeasts, fungi and algae as sources of single cell oil has been examined. A particular role of these systems in the production of specialty oils has been suggested. Enzyme systems, either associated with the intact cell or in isolation, can be used to varying degrees of success in either a free or immobilized form. Particular reference has been made to application of these systems to reactions including specific hydrolysis of triacylglycerols, acylation of glycerol, interesterification of triacylglycerols, wax ester formation and steroid transformations. Consideration has been given to particular plants and microorganisms as sources of new fats and oils. The major impact of biotechnology on the industry is believed to be associated with the production of high value specialty products including cocoa butter substitutes, biosurfactants, waxes and various prostaglandin derivatives. General consideration has been given to the possible relative importance of plant and microbial systems, engineering and scale-up problems, and overall economics of present biotechnological procedures.

A high-performance liquid chromatographic (HPLC) method has been developed to separate sinapine and sinapic acid from other phenolics in canola seed and meal in a single run. The separation was achieved with a reverse-phase C18 column. Owing to the higher recovery of phenolics and ease of use, refluxing with 100% methanol for 20 min was selected as the extraction method for HPLC analysis and determination of total phenolics using Folin-Ciocalteu reagent. A 10-min isocratic/linear/concave gradient and a 15-min isocratic/linear gradient were selected as the best gradients for the separation of these phenolic compounds. Peak identities for sinapine and sinapic acid were verified with ion exchange separation followed by HPLC analysis. The method was calibrated using sinapine bisulfate and sinapic acid standards; correlation coefficients (R 2) for the calibration curves were 0.997 and 0.999 for sinapine bisulfate and sinapic acid, respectively. The extinction coefficient of sinapine was determined to be 1.16 times that of sinapic acid at the detector wavelength (330 nm). Applying this method to routine canola phenolic analyses can greatly reduce the cost by simplifying the procedures and reducing the time required for each determination.

Dầu hạt của Euphorbia lagascae Spreng. chứa 57% axit cis-12,13-epoxy-cis-9-octadecenoic (axit vernolic). Hàm lượng trivernolin trong các glyceride của loài này cho thấy sự phân bố ngẫu nhiên hoặc ngẫu nhiên có hạn của axit vernolic. Hạt từ 57 loài khác trong họ Euphorbiaceae đã được phân tích về hàm lượng dầu và protein cũng như thành phần axit béo của các loại dầu. Các giá trị i-ốt (I.V.) của các loại dầu dao động từ 87 đến 221. Trong số các loại dầu này, có những mẫu chứa tới 76% axit linolenic, 77% axit linoleic hoặc 84% axit oleic.

The wax ester composition of pressed olive oil and its variation during olive ripening were investigated by column chromatography/GC-on column technique. Six compounds were identified: C36, C38, C40, C42, C44 and C46 wax esters, which were grouped as total detected wax esters (TDWEs). The European Union (EU) includes C40, C42, C44 and C46 waxes (TEWEs) as a distinctive characteristic between different categories, with a maximum total content ≤250 mg/kg for an extra virgin olive oil. The International Olive Council (IOC) includes C42, C44 and C46 waxes (TIOCWEs) as a purity parameter, with a maximum total content ≤150 mg/kg for an extra virgin olive oil. The analytical technique proposed by EU and IOC do not separate the wax esters from fatty acids esters with diterpenic alcohols (phytol and geranylgeraniol) that interfere with detected peaks. Although the examined cultivars were grown in the same geographical area and the same agricultural practices were applied to the trees, ANOVA analysis found significant differences among the oils extracted with the same machinery. The oil produced from the Itrana cultivar showed the lowest content in TEWEs (25.00–39.00 mg/kg) and in TIOCWEs (5.67–9.00 mg/kg). Wax content in Leccino and Pendolino cultivars showed a significant tendency to decrease during olive maturation, and a tendency to increase in all other cultivars from the first to the last harvest date when olive pigmentation changed from green to black.