FA and tocopherol composition of Vietnamese oilseeds

Seeds of 40 oilseed species from 23 different plant families (Brassicaceae, Cucurbitaceae, Fabaceae, Sapindaceae, Malvaceae, Gnetaceae, Clusiaceae, Bruseraceae, Ranunculaceae, Convolvulaceae, Amaranthaceae, Tiliaceae, Basellaceae, Solanaceae, Umbelliferae, Labiatae, Compositae, Theaceae, Euphorbiaceae, Caesalpiniaceae, Sapotaceae, Anacardiaceae, and Connaraceae) grown in Vietnam were analyzed for oilseed oil content, FA, and vitamin E. The seed oil content varied between 0.2 g/100 g for Mangifera indica and 75.7 g/100 g for Calophyllum inophyllum, whereas only nine seeds contained more than 40% oil. The tocopherol content ranged from 26 (Sapindus mukorossi) to 9361 mg/kg (Litchi chinensis). In nine seed oils unusual FA such as conjugated, cyclopropenoic, or epoxy FA were found.     

Volatile aroma compounds of raw and roasted palm kernel

The volatile aroma compounds of raw and roasted palm kernel, isolated by hydrodistillation, were analysed by g.l.c. and g.c.-m.s. A number of compounds have been identified for the first time in this commodity. It was found that δ-lactones and ethyl esters were predominant in the flavour profile. In roasted palm kernels, flavour analysis showed the presence of a number of pyrazines formed during heating. Most of the lactones and esters identified in raw palm kernel were present in the roasted samples also. The flavour concentrate included a number of fatty acids in both the raw and roasted samples, in small amounts.     

Proton magnetic resonance imaging of lipid in pecan embryos

Magnetic resonance images of plant tissues typically are manifestations of water protons in tissues. Within oilseeds, however, lipids contain a major portion of the mobile protons, which should enable specific imaging of lipids. In this study, experiments were done to demonstrate spin-echo imaging (SEI) and chemical-shift imaging (CSI) of lipid within nonimbibed and imbibed embryos of pecan (Carya illinoensis), a high-lipid seed. Magnetic resonance spectra of airdry embryos contained a single major peak for lipid, whereas those of imbibed embryos contained separate peaks for water and lipid. This separation of spectral peaks enabled CSI of distributions of either lipids or water in imbibed embryos. A longer spin-spin relaxation time of lipid protons than of water protons in imbibed embryos allowed selective SEI of lipids in those embryos. SEI of normal, dry embryos revealed fairly uniform distribution of lipids across tissues. Similar images of embryos damaged by the fungusPhoma exocarpina or the insectZerara viridula were less intense than those of a normal embryo, reflecting the lower oil contents of the damaged embryos. Magnetic resonance imaging should provide a useful technology for studying lipid distribution and metabolism within oil seeds.     

粮油种子平衡水分测定方法及数据处理

介绍了采用静态称重法测定谷物和油料种子平衡水分的原理、方法,以期对我国粮食平衡水分研究和应用有参考意义。     

反相高效液相色谱法测定油料饼粕氨基酸含量

采用反相高效液相色谱（RP-HPLC）法测定油料饼粕氨基酸含量,条件为:C₁₈（4.6mm×250mm,5μm）柱,流动相A为0.1mol/L的醋酸钠（pH6.5）-乙腈溶液（V/V185:14）,流动相B为80%乙腈水溶液（V/V）,流速为1mL/min,梯度洗脱,检测波长254 nm,柱温40℃。比较花生、菜籽和棉籽等饼粕样品中氨基酸组成和含量,分析结果表明菜籽饼粕氨基酸组成最合理,棉籽蛋白氨基酸含量最高。     

Feeding the multitude — where is tomorrow's equivalent of the five loaves and two fishes?

Despite the fears of Malthus, production of the major food products (grains, oilseeds, and livestock) has kept pace with population growth on a global basis, though not always on a regional basis. This claim is supported with appropriate numbers and the ways in which food supplies have been increased are discussed. It seems likely that this can continue for at least another twenty years but the situation is less clear thereafter. However, man s ingenuity continues to provide hope for a favourable outcome.     

气相色谱-质谱法测定粮油制品中的二甲基黄和二乙基黄含量

目的建立气相色谱-质谱法测定粮油制品中二甲基黄和二乙基黄的含量的分析方法。方法试样以1%醋酸的乙腈提取,采用油基质萃取管净化和HP-5MS色谱柱分离,质谱采用全扫描和选择离子模式测定,以外标法定量。同时考察了不同的提取溶剂及净化方式对回收率的影响。结果在添标水平为1、10和25 mg/kg时,二甲基黄和二乙基黄的平均回收率为76.3%~89.3%,相对标准偏差为3.0%~8.7%,二甲基黄的方法检出限为0.002 mg/kg,二乙基黄的检出限为0.001 mg/kg,符合检测方法参数的确认要求。结论该方法快速、准确,适用于粮油制品中的二甲基黄和二乙基黄含量。     

Attractancy of diethyl ether extracts of Arachis hypogaea (Linnaeus) (Papilionaceae), Citrullus lanatus (Thunberg) (Cucurbitaceae) and Irvingia gabonensis var. excelsa (Baillon) (Irvingiaceae) to Oryzaephilus mercator (Fauvel) (Coleoptera: Silvanidae)

Volatiles of the diethyl ether extracts of I. gabonensis, C. lanatus and A. hypogaea attracted 1–7 and 28–42-day-old adult O. mercator when tested in a two-choice pitfall Petri dish bioassay. For both age groups, a significant difference was observed in response between fed and starved adults to the different extracts. Differences in starvation time did not affect responses of individuals in the 1–7-day-old group; a significant effect was observed in the 28–42-day-old group.

Adults, 28–42-day-old were significantly more responsive to virtually all extracts than 1–7-day-old adults. Responses of adults in each age group to the different extracts were not significantly different. The time of trial within the period 0900–1900 h did not significantly affect the response of adults in both age groups, starved for 2 days, to any extract.     

Comparison of different methods for the determination of the oil content in oilseeds

The investigation and assessment of the oil content of oilseeds are important criteria, especially for the oil milling trade. Standard methods for the determination of the oil content of oilseeds are very time consuming, with extraction periods of 4 to 8 h. Three different oilseeds—rapeseed, sunflower, and soybean—are extracted by supercritical fluid extraction (SFE), accelerated solvent extraction, microwave-assisted extraction, solid fluid vortex extraction, and Soxtherm, and the results are compared with the result of the German Fat Science Society (DGF) standard method B-I 5 (87). Besides, the extracts are analyzed regarding the content of tocopherols as a parameter for mild extraction conditions and the content of diglycerides and free fatty acids as parameters for the content of more polar lipids. The results of the determination of the oil content under optimal conditions are comparable with the results of the DGF standard method B-I 5 (87). There are no significant differences between the different methods. The content of tocopherols is dependent upon the extraction method and the type of oilseed. The highest content is obtained by SFE. The content of diglycerides and free fatty acids varied according to the oilseed.     

Shape factors for the analysis of diffusion in air drying of grains

The shape factors (φ) of different varieties of wheat, corn (maize), rice, sorghum, sunflower seeds and soybean have been experimentally determined. Shape factor values ranged from 0.63 to 0.99. These values are useful for correcting literature moisture diffusion coefficients in grains of different shapes, obtained from the analysis of drying curves; this allows direct comparison of diffusivity in different grains.