Wx^mp基因背景下可溶性淀粉合成酶基因SSⅡa和去分支酶基因PUL对水稻蒸煮食味品质的影响

【目的】分析在同一主效基因(Wx^mp)背景下可溶性淀粉合成酶基因SSⅡa和去分支酶基因PUL对稻米蒸煮食味品质的影响,以期为水稻品质遗传改良提供依据。【方法】选择在SSⅡa和PUL存在多态性而其他淀粉合成酶相关基因没有多态性的半糯品系宁0145和粳稻品种武运粳21进行杂交,获得F2群体与F3株系。利用分子标记,选择含有Wx^mp基因的F2单株与F3株系,将这些F2单株与F3株系分成SSⅡa^nPUL^n、SSⅡa^nPUL^w、SSⅡa^wPUL^n和SSⅡa^wPUL^w4种基因型(n和w分别表示该基因来源于宁0145和武运粳21),分析不同基因型蒸煮食味品质性状的差异,探讨同一Wxmp基因背景下不同SSⅡa和PUL等位基因对蒸煮食味品质性状的影响。【结果】不同基因型间蒸煮食味品质性状均存在显著差异,来源于武运粳21的SSⅡa^w基因和PUL^w基因分别使直链淀粉含量增加0.29%~1.00%和0.62%~1.18%,且PUL的效应大于SSⅡa,两者间存在互作效应。SSⅡa^w基因和PUL^w基因降低胶稠度和崩解值,提高了热浆黏度、冷胶黏度、消减值和回复值,对糊化温度、峰值黏度和峰值时间的作用较小。【结论】明确了Wx^mp背景下SSⅡa和PUL基因对稻米蒸煮食味品质的遗传效应,该研究结果为SSⅡa和PUL基因的分子标记辅助选择改良稻米品质提供了理论依据。     

煮熟和干燥处理对黄藤笋抗氧化活性的影响

通过测定黄藤熟笋、生笋(鲜切笋)、熟笋干和生笋干的水和4种不同浓度乙醇提取物中的自由基清除能力、总还原能力、总多酚含量和总黄酮含量,研究了煮熟、干燥加工方法对黄藤笋提取物抗氧化活性的影响。结果表明,煮熟处理能保持或提高提取物的抗氧化活性,干燥处理则相反。乙醇提取物比水提取物具有更高的抗氧化活性,以50%~75%的乙醇提取溶剂效果最好。熟笋在所有溶剂中的自由基清除能力、总还原能力、总多酚含量和总黄酮含量均表现出最高水平,表明煮熟是黄藤笋适宜的加工利用方式。     

Fatty Acid Porfiles of Farm-Raised Catfish Fillet:

Fatty acid profiles of the total lipids and the phospholipid classes of farm-raised channel catfish (Ictalurus punctatus) fillets were analyzed. Monoenes represented 49.22 mol% of the total lipid fatty acids while polyunstaturated fatty acids (PUFA) accounted for 19.37 mol%. The total n-3 PUFA content was low (4.22 mol%). The total saturated fatty acids as 31.44 mol %. Catfish contained phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), lysophosphatidylcholine (LPC), and sphingomyelin (SPH). Analysis for the individual phospholipid class fatty acid profiles indicated that PI had a high concentration of 18:0 (33.20 mol%) and 20:4 n-6 (13.08 mol%). Phosphatidylethanolamine had the highest concentrations of combined eicosapentaenoic acid, and docoshahexaenoic acid, of 17.37 mol%. Higher ratios of n-3/n-6 PUFA were found in the phospholipid classes than the total lipids. LPC and SPH did not contain measurable PUFA of the n-3 series. The level of 18:1 n-9 in PC, PE, and LPC was approximately 31 mol% whereas in PI, PS, and SPH, the level was approximately 16 mol%. The understanding of the basic distribution of fatty acids in the individual phospholipid classes of channel catfish may be an essential first step in explaining the protective role of 18:1 n-9 and n-3 PUFA against thrombotic and cardiovascular disorder in humans.     

Pigeonpea Nutrition and Its Improvement

Abstract

Pigeonpea (Cajanus cajan [L.] Millsp.), known by several vernacular and trade names such as red gram, tuar, Angola pea, Congo pea, yellow dhal and oil dhal, is one of the major grain legume crops of the tropics and sub-tropics. It is a favorite crop of small holder dryland farmers because it can grow well under subsistence level of agriculture and provides nutritive food, fodder, and fuel wood. It also improves soil by fixing atmospheric nitrogen. India by far is the largest pigeonpea producer where it is consumed as decorticated split peas, popularly called as ‘dhal’ In other countries, its consumption as whole dry seed and green vegetable is popular. Its foliage is used as fodder and milling by-products form an excellent feed for domestic animals. Pigeonpea seeds contain about 20-22% protein and appreciable amounts of essential amino acids and minerals. Dehulling and boiling treatments of seeds get rid of the most antinutritional factors such as tannins and enzyme inhibitors. Seed storage causes considerable losses in the quality of this legume. The seed protein of pigeonpea has been successfully enhanced by breeding from 20-22% to 28-30%. Such lines also agronomically performed well and have acceptable seed size and color. The high-protein lines were found nutritionally superior to the cultivars because they would provide more quantities of utilizable protein and sulfur-containing amino acids.     

Effects of Cooking on Anthocyanin Concentration and Bioactive Antioxidant Capacity in Glutinous and Non-Glutinous Purple Rice

Purple rice is a source of bioactive antioxidants for rice consumers. Loss of the major antioxidant compounds after a range of cooking processes was evaluated by measuring the changes in anthocyanin concentration (ATC) and antioxidant capacity (DPPH activity) of four non-glutinous and four glutinous genotypes. However, soaking in water prior to cooking generally decreased more ATC and antioxidant capacity in non-glutinous than in glutinous genotypes. Wet cooking (WC) and soaking before wet cooking (S-WC) led to lose almost all the ATC and antioxidant capacity with only slight variation between genotypes. In the glutinous genotype Pieisu, which had the highest raw rice ATC, ATC remained the highest when cooked by the WC method. By contrast, almost no ATC remained after WC and S-WC in the low ATC genotypes such as Kum Doi Saket. Overall, the loss of ATC was greater in non-glutinous than in glutinous genotypes for both WC and S-WC methods, but the reverse occurred for antioxidant capacity. WC using electric rice cooker retained higher ATC than the pressure cooking. Thus, for genotypes with high ATC and antioxidant capacity, the selection of cooking method is critical for retaining and stabilizing rice quality.     

Effect of the Cooking Process on the Gelling Properties of Whole and Minced Jumbo Lump of Blue Crab (Callinectes sapidus)

Commercially, crab meat is obtained by hand-picking after a cooking process, followed by pasteurizing or canning. Jumbo lump is one of the pieces of meat obtained from the blue crab. The aim of this study was to evaluate the effect of the commercial cooking process (boiling and steaming) on the mechanical and functional properties of whole jumbo lump and the gels obtained from cooked and minced jumbo lump from blue crab (Callinectes sapidus). The gels were prepared combining the washing process and microbial transglutaminase. The boiling and steaming processes showed a different effect on the textural and color properties. Whole jumbo lump pieces cooked by immersion in boiling water showed a higher hardness value as compared to steamed jumbo lump pieces, suggesting a different internal structural. The cooking processes used in this study did not modify the water holding capacity, gelling capability, or color of the minced jumbo lump. The addition of microbial transglutaminase to washed minced jumbo lump improved the hardness, cohesiveness, and chewiness of gels elaborated with boiled or steamed jumbo lump, which allowed the textural properties similar to those of the whole jumbo lump.     

玉米生料发酵生产酒精的研究

采用低温淀粉酶对玉米生料发酵酒精技术进行研究,结果表明,在玉米粉碎度为40目,活性干酵母加量0.3%时,玉米淀粉生料发酵制备酒精的最佳工艺条件为:初始底物质量分数为30%,发酵温度30℃,搅拌转速为75 r/min,自然初始pH值,低温淀粉酶加量为200 U/g(液化酶100 U/g,糖化酶100 U/g),在此条件下,发酵醪的酒精体积分数达到16.4%。     

中国鲜面条耐煮特性及评价指标

以我国北部和黄淮冬麦区的46份主栽小麦品种和育成品系为材料, 分析了品质性状与煮熟面条冲洗水中总有机物含量(TOM)、干物质蒸煮损失率、面条吸水性和黏性等面条耐煮性指标的关系。结果表明, 小麦品种的磨粉品质、面团流变学特性、淀粉品质及TOM值、蒸煮损失率和黏性等面条耐煮性指标存在较大变异。拉伸面积和最大抗延阻力与TOM值呈显著负相关, 相关系数分别为-0.66 (P<0.01)和-0.56 (P <0.01); 稳定时间、拉伸面积和最大抗延阻力与面条煮6 min和10 min后鲜重的相关系数为-0.55~ -0.63 (P <0.01), 耐揉指数与二者的相关系数分别为0.67 (P<0.01)和0.69 (P<0.01); 糊化温度与面条煮10 min后鲜重呈极显著正相关(r = 0.60, P<0.01), 说明提高小麦面粉的蛋白质含量、面筋强度可以显著改善面条耐煮特性, 蛋白质特性是影响面条耐煮性的主要品质因子, 淀粉糊化参数对面条耐煮性也有一定影响。TOM值与面条煮6 min和10 min后鲜重呈显著正相关, 相关系数分别为0.66 (P<0.01)和0.69 (P<0.01); 面条煮6 min与煮10 min后鲜重也呈高度正相关(r = 0.86, P<0.01)。建议将10 g鲜面条煮10 min后的鲜重≤21.0 g作为优质鲜面条耐煮性的主要评价指标。     

运用生本教育理念 提高烹饪教学课堂气氛

生本教育演绎的是积极、欢乐、优质、高效的课堂教学。它的核心理念体现在最大程度地调动学生的内在积极性,组织学生自主学习,激发学生的积极情感,进而产生对烹饪技能学习的热烈追求、积极思考、主动探索的课堂教学氛围。