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71.
太行山水柿果实成熟过程中主要成分含量的动态变化   总被引:3,自引:0,他引:3  
对太行山水柿转色期后果实成熟过程中总糖、蛋白质、单宁等主要成分的变化规律进行研究,以确定最佳采收期.结果表明,在果实成熟过程中,可溶固形物和总糖的含量呈上升趋势,可溶固形物和总糖含量分别为180 g.kg-1,150 g.kg-1左右达到峰值,然后趋于平稳;单宁和蛋白质含量呈逐渐减少趋势,其含量分别在12 g.kg-1,6 g.kg-1左右时相对平稳;原果胶含量逐渐降低,可溶性果胶含量逐渐上升;总酸含量较低,整个过程变化不大.因此采收期的确定应以含糖量为准,当表皮呈现品种特有的橙黄色,含糖量达150~170 g.kg-1时采收,此时水柿可维持较高的硬度,有助于运输中的稳定性和完整性.  相似文献   
72.
高粱中单宁含量的检测方法分析   总被引:2,自引:1,他引:1  
结合国家标准GB/T15686—2008与实验室的实际情况,建立高粱中单宁含量的测定方法。对显色反应时间、酸碱性、溶液反应温度等方面进行了反复的验证。经过对单宁标准系列的测定,结果表明,显色剂与单宁反应后溶液颜色变化显著,用分光光度计在波长为525 nm处测定,单宁质量浓度在0.1~5 mg/mL范围内服从朗伯-比耳定律,回归方程为A=0.9640c+0.219 3,相关系数R2为0.995 4。经过对17个高粱品种样品单宁含量进行测定,该方法的回收率在97.3%~103.4%范围内。该方法简便快捷、灵敏度高、特异性好、结果准确,适合大批量样品分析,可应用于高粱中单宁含量的检测。  相似文献   
73.
The nutritive quality of sorghum-commonbean (40:60) tempe manufactured byRhizopus oligosporus: Rhizopus oryzae (1:1) mixed culture fermentation was determined. The protein, crude fat and ash content increased slightly while carbohydrates decreased. The dietary fibre of the tempe increased by 10%. Mould fermentation increased the content of reducing sugars, total acid and aminonitrogen 15.3, 6.7 and 4.6-fold, respectively. It decreased the phytate content by 44% and it increased the tannic acid content by 52%.In vivo iron absorption increased from 2.8 to 12.5%. The protein efficiency ratio of tempe was 1.61±0.33; the net protein ratio was 2.39±0.20; thein vitro andin vivo protein digestibility were 88.2 and 80.0±0.05% respectively, while the protein efficiency ratio, net protein ratioin vivo digestibility of skim milk was 2.96±0.17, 3.51±0.17 and 98.0±1.87, respectively. The sorghum-bean tempe could be used for supplementary feeding.  相似文献   
74.
The nutritional quality of wild and cultivated species ofVigna has been evaluated. Wild species showed significantly higher protein content (P<0.01), antitryptic activity (P<0.005) and tannin content (P<0.025) and significantly lower protein digestibility (P<0.005). No significant differences were found with regard to protein quality, measured as chemical score corrected by the digestibility; sulphur amino acids turned out to be limiting in both groups. In addition no correlations were found between sulphur amino acids and protein levels, or between sulphur amino acid and trypsin inhibitor levels.Selected lines showed an improvement from the nutritional point of view linked to lower antitryptic factors and tannin content, which may give rise to a decreased resistance to pests. For all the properties considered, whether physical or biochemical, wild samples presented wider variations and the types considered most primitive were those that differed most from the cultivated ones, whose properties were altogether more consistent. In vitro protein digestibility turned out to be a useful parameter in evaluating wild and improved samples.IITA (International Institute of Tropical Agriculture) fellowship recipients.  相似文献   
75.
Two faba bean cultivars (317/99/81 and Giaz/402) obtained from Shambat Research Station in Northern Sudan, were used for this study. Investigation showed that the tannin contents of untreated seeds were 0.077% and 0.067% for cultivars 317/99/81 and Giza/402. In vitro protein digestibility values were 80.68% and 81.48% for the two cultivars, respectively. The extractable tannin content of the faba bean cultivars was markedly reduced by imbibing water or Na2CO3 solution into whole seeds and incubating them at 30°C for 1, 3, 6, 12 or 24 hours, or at 100°C for 5, 10 or 20 minutes. The extent of reduction depended on time, temperature, and Na2CO3 concentration; the percent tannin extracted and percent in vitro protein digestibility increased with time or Na2CO3 concentration, while application of high temperature reduced the time.  相似文献   
76.
作者采用醇提,F-D试剂显色,分光光度法比色测定了红豆草不同生育期各个器官鲜草和干草的丹宁含量,结果表明:鲜草比干草丹宁含量高;全株、叶子和茎杆中丹宁含量随生长天数均呈有规则的下降;叶子丹宁含量高于全株,茎杆低于全株;蕾中丹宁含量与同期叶子相近,花和籽接近全株,荚接近茎的含量。  相似文献   
77.
The effects of inclusion of persimmon peel (PP) in total mixed ration (TMR) silage on its nutrient composition, tannin content, and in vitro ruminal fermentation were studied. Four types of TMR silages containing 0, 50, 100, and 150 g/kg of PP on a dry matter basis were prepared. The dietary contents of non‐fiber carbohydrate (NFC) decreased, while soluble protein fraction increased after ensiling of the TMR. In the TMR silages, the content of insoluble tannin increased (p < .05) with increasing PP level. The fraction of soluble protein decreased linearly (p < .01), while that of neutral detergent insoluble protein increased linearly (p < .01) with increasing the PP level in the TMR silages. The total gas and methane yields from the in vitro rumen fermentation of the TMR silages were lower (p < .01) than those of pre‐ensiled TMR and declined linearly (p < .01) with increasing PP level. These results indicate that adding PP to TMR silage may resist the breakdown of dietary protein during the ensiling process, although the ruminal fermentability of TMR possibly decreased after ensiling due to the loss of NFC.  相似文献   
78.
【目的】 研究单宁添加剂对育肥羊生产性能、血液生化指标和养分消化率的影响。【方法】 选择30只五月龄,体重为25~30 kg的育肥羊随机分成3组,每组10个重复。分别是空白对照组:A组,饲喂基础日粮;试验组:B组在基础日粮中添加10 g/d单宁,C组在基础日粮中添加15 g/d单宁。试验预饲期为7 d,正饲期为42 d,整个试验周期为 49 d。饲喂结束后,检测其生长性能、相关血清生化指标和营养物质表观消化率。【结果】 B组和C组的日增重都高于A组;与A组相比,B组和C组的谷丙转氨酶水平显著提高(P<0.05);B组和C组的总蛋白、白蛋白、球蛋白、肌酐和葡萄糖等血清生化指标均无显著影响;与A组相比,B组的碱性磷酸酶含量显著提高(P<0.05),C组差异不显著;B组的粗蛋白表观消化率低于A、C两组(P>0.05),干物质、粗脂肪、钙和NDF等的表观消化率均无显著差异。【结论】 在育肥羊日粮中添加10、15 g/d单宁添加剂可以改善育肥羊的生产性能,对谷丙转氨酶、碱性磷酸酶、尿素和粗蛋白含量的影响较大。  相似文献   
79.
为制备无甲醛的环保型生物基木材胶黏剂,以单宁和纳米SiO2改性脱脂豆粉制备大豆基胶黏剂(DSF),并分析了改性大豆基胶黏剂的性能。研究结果显示:单宁和纳米SiO2二元复合改性大豆基胶黏剂(DSF-T-SiO2)在固化过程中能够形成稳定的交联结构;TG分析表明单宁和SiO2改性显著提高了胶黏剂的热稳定性;单宁改性大豆基胶黏剂(DSF-T)可提高干态和湿态胶合性能,纳米SiO2改性大豆基胶黏剂(DSF-SiO2)的干态胶合性能略有提高,但湿态胶合性能无明显改善。经分析以25 g脱脂豆粉、 5 g单宁、 0.1 g纳米SiO2和70 g去离子水混合均匀搅拌得到的改性胶黏剂DSF-T-SiO2-2的起始黏度比未改性的DSF降低了79.58%;DSF-T-SiO2-2的固化胶层水溶解率为(27.5±0.05)%,比对照组DSF下降了28.4个百分点。此外,DSF-T-SiO2-2...  相似文献   
80.
杨梅叶提取物抗烟草花叶病毒活性及其化学成分初步研究   总被引:7,自引:1,他引:7  
以烟草花叶病毒(Tobaccomosaicvirus,TMV)为供试病毒,对杨梅叶提取物抗病毒活性进行测定.结果表明,杨梅叶提取物具有较强的体外钝化和抗病毒侵染作用;通过系统预试和含量测定,初步确定杨梅叶提取物中主要含有黄酮和鞣质2类成分,两者含量分别在水和体积分数为70%的乙醇提取物中较高.  相似文献   
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