油莎豆白酒发酵工艺优化及其品质指标检测

以油莎豆饼和高粱为原料，分别采用固态和液态发酵工艺酿造油莎豆白酒，对油莎豆白酒的发酵工艺进行选择。在此基础上，采用单因素试验及正交试验探究发酵温度、糖化酶添加量以及活性干酵母添加量对油莎豆白酒发酵及理化指标的影响，从而确定油莎豆白酒的最佳固态发酵工艺条件，并对油莎豆白酒发酵过程中酒醅的发酵指标进行实时监测。结果表明，油莎豆白酒的最佳发酵工艺为固态发酵，最佳发酵工艺条件为发酵温度23 ℃，糖化酶添加量190 U/g、活性干酵母添加量0.5‰。在此优化条件下，油莎豆白酒的酒精度为9.2%vol，总酯含量为2.96 g/L，总酸含量为1.45 g/L，乙酸乙酯含量为2.42 g/L，出酒率达到41%。油莎豆白酒发酵过程中，酒精含量逐渐升高，最后趋于平缓，发酵结束后，酒精度达9.2%vol；发酵温度先上升后下降，第6天时酒醅温度达到峰值（27.9 ℃）；剩余淀粉含量逐渐下降，发酵结束后，淀粉消耗12.21%。     

油莎豆辛烯基琥珀酸淀粉酯的制备及结构表征

本研究以油莎豆淀粉为原料,以辛烯基琥珀酸酐(octenyl succinic anhydride, OSA)为酯化剂,选用水相法制备OSA淀粉酯。对不同OSA用量的油莎豆OSA淀粉酯的糊液透明度、冻融稳定性、抗性淀粉含量和接触角进行分析,通过傅里叶红外光谱、扫描电镜和X-射线衍射对淀粉酯结构进行表征。结果表明：油莎豆OSA淀粉酯取代度随OSA用量的增加而增大,反应效率与之相反。淀粉酯糊液透明度、冻融稳定性、抗性淀粉含量、接触角均随OSA用量的增加呈现上升趋势。傅里叶红外光谱表明淀粉酯在1732 cm_^-1和1558 cm_^-1出现酯羰基和羧酸的吸收峰。扫描电镜显示淀粉酯形态特征无明显变化,部分颗粒表面出现轻微腐蚀和裂纹。X-射线衍射分析证实,随酯化反应程度加深,淀粉酯部分晶体结构被破坏,淀粉相对结晶度下降。     

Physical and chemical properties of chufa (Cyperus esculentus L) tubers grown in the Çukurova region of Turkey

Four lines of chufa (Cyperus esculentus) grown in 1998 and 1999 in the Çukurova region of Turkey were analysed for their physical properties, proximate chemical composition and fatty acid contents. The chufa lines contained on average (g kg^?1) 932.8 dry matter, 245.0 crude lipid, 256.8 starch, 14.3 ash, 50.5 protein, 89.1 crude fibre, 17.1 reducing sugar, 154.3 total sugar and 130.4 sucrose. Hunter L, a⁺ and b⁺ colour values of ground chufa samples were in the ranges 55.93–60.59, 3.71–5.09 and 15.60–16.85 respectively. Individual chufa tubers weighed between 0.224 and 0.283 g. The fatty acid composition of chufa oil included (g kg^?1) 689.2–732.9 oleic acid, 125.5–141.2 palmitic acid and 99.6–154.6 linoleic acid, which is comparable with that of olive oil. After storage for 1 year the differences in mean values were significant (p < 0.05). © 2002 Society of Chemical Industry     

烘烤温度对浓香油莎豆油风味及综合品质的影响

在浓香型油脂的生产中油料烘烤温度是影响产品风味的重要因素,为了对浓香油莎豆油的产品开发和工艺条件优化提供支持,采用不同温度对油莎豆进行烘烤并压榨制取浓香油莎豆油,对油莎豆油的多个品质指标进行检测分析,明确烘烤温度对油莎豆油风味及综合品质的影响。结果表明：油莎豆经140、150、160、170、180℃烘烤25 min后榨取的5个油样的酸值（KOH）为1.36～2.31 mg/g,过氧化值为1.60～2.24 mmol/kg,维生素E含量为177.82～207.14 mg/kg,甾醇含量为208.73～230.01 mg/100 g;烘烤温度对油莎豆油的脂肪酸组成影响不大,但随温度升高反式脂肪酸含量从未检出升高至0.029%,3,4-苯并\[a\]芘（BaP）含量从1.06 μg/kg升高至1.66 μg/kg,多环芳烃（PAH16）含量从63.67 μg/kg升高至72.50 μg/kg,3-氯丙醇酯均未检出;随烘烤温度升高,5个油样中挥发性成分的种类及含量分别为60种16.46 mg/kg、87种33.07 mg/kg、81种22.36 mg/kg、78种17.71 mg/kg、57种21.78 mg/kg;150℃烘烤时油莎豆油的挥发性成分的种类和含量最为丰富;赋予浓香油莎豆油烘焙坚果味等正面风味属性的主要为杂环类物质,包括2,5-二甲基吡嗪和2-正戊基呋喃,其中2,5-二甲基吡嗪在140℃时的油莎豆油中未检出,之后随烘烤温度升高,在杂环类物质中的占比从烘烤温度150℃时的24.16%升高至烘烤温度为180℃的34.06%。综合油莎豆油风味、安全品质、营养品质和质量指标,浓香油莎豆油生产中以烘烤温度不超过 160℃、烘烤时间不超过 25 min 为佳。     

Geometric Characteristics and Chemical Composition of Okra (Hibiscus esculentus L.) Grown Under Semi-arid Conditions

Abstract

A Landrace and seven foreign genotypes of okra (Hibiscus esculentus L.) were grown in a randomized complete block design at Jordan University of Science and Technology (JUST) Experimental Station in northern Jordan during the 1997 and 1998 growing seasons. The pods were studied for their physical properties, chemical composition, and mineral content. Geometric characteristics of okra fruits were significantly influenced by genotypes. Mosel and Steen had higher protein content than the Landrace, being 23.19, 22.43, and 19.96% respectively. The average fruit mass of different genotypes showed a trend similar to that found in fruit volume; Vigorpak had the highest fruit mass and volume, whereas Mosel had the lowest. Number of pods per plant showed very wide range for all genotypes, which ranged between 17 and 31. Data demonstrated that the variability within individual okra genotypes may be was due to environmental effects. High variability was observed in chemical composition among different genotypes. However, the genotype having high carbohydrate content showed low fiber content. All mineral contents (Ca, Na, Cu, Mn, Zn, Mg, P, and K) varied significantly among the genotypes except for Fe content, which showed no significant differences between genotypes. Mosel genotype was found superior in its mineral contents, whereas other genotypes might be considered good source for proteins, fiber, carbohydrate and minerals. The investigated genotypes seem to be a good source of minerals for human diet. The variation in mineral contents is probably due to genotype, environment and/or genotype environment interaction.     

Separation and Purification of α-Cyperone from Cyperus rotundus with Supercritical Fluid Extraction and High-Speed Counter-Current Chromatography

Abstract

α-Cyperone was separated and purified for the first time from essential oil of the traditional Chinese medicinal plant Cyperus rotundus L. by high-speed counter-current chromatography (HSCCC). Essential oil was obtained by extraction with supercritical carbon dioxide under the pressure of 20 MPa and temperature of 40°C. The separation was performed in one step with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (1:0.2:1.1:0.2, v/v), in which the lower phase was used as the mobile phase at a flow-rate of 2.0 ml/min in the head-to-tail elution mode. A total of 60 mg α-cyperone at 98.8% purity was yielded from 0.9 g essential oil as determined by HPLC analysis. The structure of the target compound was performed by electron impact ionization mass spectrometry (EI-MS) and further conformed by comparison with an authentic sample (National Institute of the Control of Pharmaceutical and Biological Products, Beijing, China).     

油莎豆油不同提取方法的比较

全面比较了油莎豆油的溶剂浸提法、水酶法和水酶-冻融技术这3种提取方法,探索不同提取方法的提取机理,为油莎豆油提取产业化生产提供指导。研究比较了3种油莎豆油提取方法的提取率、油品理化性质、油莎豆粕粉扫描电镜图。结果表明,水酶法和水酶-冻融技术相对溶剂浸提法更具开发潜力。     

油莎豆热风干燥特性及数学模型研究

以新鲜油莎豆为原料,研究风温和风速对油莎豆热风干燥特性的影响,计算干燥过程中有效扩散系数与活化能,并选取8种干燥动力学模型进行拟合分析。实验结果表明：热风温度越高,干燥速率越快,干燥时间越短;风速对干燥速率影响较小。本试验干燥过程主要发生在降速阶段,油莎豆有效水分扩散系数2.2856×10^-10～7.8112×10^-10,平均活化能为35.31kJ/mol,Two-term模型可以很好的反映油莎豆热风干燥过程,实验值与预测值吻合度较高,拟合效果良好。