脱脂对鲢鱼肉蛋白酶解产物的品质和抗氧化活性的影响

研究了脱脂对鲢鱼肉酶解产物的品质和抗氧化活性的影响。与未脱脂的水解产物相比,脱脂鲢鱼肉的酶解产物的水解度略有下降;胰蛋白酶酶解产物(简称DSH)的脂肪、灰分含量显著下降。鱼肉脱脂后,其蛋白水解产物的腥味大大下降。未脱脂鱼肉的胰蛋白酶水解产物(简称SH)的L*值下降,a*值、b*值增加;经过7个月保藏后发现,SH呈现黄褐色,而DSH基本保持乳黄色的外观。DSH具有较高的抑制脂肪酸氧化和清除羟基自由基活性。     

棉籽油的深度分提工艺

新疆棉籽油含有700 mg/kg的蜡质和26%～28%的固体脂，由于新疆气温多在零度以下，棉籽油在运输、储存和销售过程中易产生固化、沉淀、发朦，影响棉籽油的外观、食用和销售。为了保持包装棉籽油透明，提高棉籽油的质量和附加值，对棉籽油进行深度分提以脱蜡脱脂。介绍了棉籽油深度分提工艺，即在15 ℃脱除蜡质，在7 ℃分提出棕榈酸甘三酯，继续降温至-10 ℃分提出棕榈酸甘二酯、棕榈酸甘一酯及其他硬脂，最终得到在低温下保持透明的棉籽液油。     

棉短绒低温低压制浆的方法

棉短绒在低温工况条件下先脱脂后进行双氧水蒸漂制浆,提高得率,降低污染。     

米糠油制取工艺关键技术研究进展

米糠油作为一种很好的健康营养油,受到了越来越多食用油生产企业的关注,但是由于米糠油加工工艺以及技术的复杂性,使其生产量的快速增长受到很大的限制。针对米糠油加工过程中遇到的一些难点,较全面的综述了米糠的稳定化处理、米糠油的脱酸、脱色以及脱蜡脱脂技术等关键技术的研究发展。     

脱脂前后玉米酒糟品质变化的研究

对脱脂前后玉米酒糟的品质进行了研究.结果表明:脱脂后的DDGS中蛋白质有所提高,水分含量显著降低;植酸磷含量变化不明显,而总磷含量有所提高;氨基酸含量提高,生成一些挥发性烯醛和酯类物质,具有较好的气味,改善了DDGS的适口性.     

Physicochemical,Pasting, and Functional Properties of Amaranth Seed Flours: Effects of Lipids Removal

The present work was carried out to evaluate physicochemical (composition, hunter color, and sodium dodecyl sulfate–polyacrylamide gel electrophoresis [SDS‐PAGE]), pasting, and functional properties (foaming, emulsification, water, and fat absorption capacity) of amaranth full‐fat flours from 6 lines/cultivars (AFs), and to see the effects of lipid removal/defatting on these properties. Protein, ash, and lipid content of AFs ranged between 12.5% to 15.2%, 3.0% to 3.5%, and 7.1% to 8.0%, respectively. The flours showed a number of bands between 97 and 7 kDa, with main subunits of approximately 58, 37, 33, 31, 23, and 16 kDa in the SDS‐PAGE profiles. The protein content and L* value increased, while b* values decreased following defatting for most of the lines/cultivars. The defatted flours (DAFs) had higher final viscosity and stability (lower breakdown viscosity) as compared to counterpart AFs. The protein profiling of the flours was not affected with the lipid removal/defatting. However, water absorption capacity and foam stability of the flours improved upon defatting. Principal component analysis revealed that pasting temperature was positively related to lipid content, while breakdown viscosity was negatively related to protein content. Foaming properties (capacity and stability) showed negative relationship with lipid content, and positive with protein content, ash content, water, and fat absorption capacity.     

Composition and Functional Properties of Soy Protein Isolates Prepared Using Alternative Defatting and Extraction Procedures

ABSTRACT: In this study, the effects of alcohol defatting using ethanol, methanol, and non-alcoholic aqueous extraction methods on the yield, purity, and functionality of soy protein isolates were investigated. Soy protein extraction conditions were also modified (heat and mild acidic treatment before protein alkaline extraction, heat isoelectric precipitation, and non-neutral resolubilization of proteins), and the effects on the isolate properties were evaluated. Results showed that ethanol and aqueous extraction were potential alternatives to hexane. The soy protein isolates (SPI) obtained from these samples had protein contents of more than 90% and 84%, respectively, with functional properties comparable to those of SPI prepared from hexane defatted meal. Major differences were a decrease in the emulsifying activity properties of the SPIs resulting from the alternative defatting techniques, with, however, improved emulsion stability and foaming properties for the aqueous extracted SPIs. A marked decrease in the fat-holding capacity of the SPI made from methanol defatted meal was also noted. Modifying the protein isolation procedure also greatly influenced the functional properties of soy protein isolates. The results of the present investigation demonstrate that soy processing conditions can be modified to obtain soy proteins ingredients with specific functional properties.     

脱脂对糯玉米淀粉热力学特性的影响

以4个糯玉米淀粉为材料,对其进行脱脂处理,分析了其对淀粉热力学特性的影响。结果表明,脱脂使淀粉中的磷元素含量显著降低,导致淀粉的起始温度、峰值温度、终值温度、峰值指数和热焓值降低,糊化范围扩大。淀粉和脱脂淀粉糊化冷藏后发生回生,表现为脱脂增加了回生淀粉的热焓值,进而增加了淀粉的回生值和峰值指数,而起始温度、峰值温度、终值温度和糊化范围受脱脂影响较小。淀粉和脱脂淀粉的热焓值存在显著的基因型差异,淀粉的热焓值以渝糯408最低,脱脂淀粉的热焓值以郑彩糯1号最低。淀粉回生后热焓值和回生值差异较小,而脱脂淀粉回生后热焓值和回生值以YA30142最高,郑彩糯1号最低。     

改性谷朊粉的制备及其凝胶结构分析

先将谷朊粉进行脱脂处理,然后采用微波、三氯氧磷和转谷氨酰胺酶法对谷朊粉进行修饰,并使用电子显微镜扫描分析了不同干燥工艺制备的改性谷朊粉凝胶结构.结果表明:脂肪对改性谷朊粉的凝胶性能影响较小,改性谷朊粉的凝胶临界浓度为16%,冷冻干燥比常压干燥更能明显地保持改性谷朊粉的交联结构.因此,酶法改性结合冷冻干燥是一种制备具有优良凝胶性能改性谷朊粉的先进工艺.