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1.
微波对马铃薯回生抗性淀粉生成的作用   总被引:1,自引:0,他引:1  
通过糊化、酶解、微波处理、高压处理和冷藏等工艺制备马铃薯回生抗性淀粉,研究微波对马铃薯回生抗性淀粉生成的作用。研究表明,微波处理功率、处理时间和高压温度对马铃薯回生抗性淀粉产率有明显影响;微波处理条件下,马铃薯回生抗性淀粉最佳制备工艺为:料水比10g/100mL,pH值6.0,α-淀粉酶加量0.6mL/100mL,在95℃条件下酶解0.5h,微波处理功率和时间分别为400W和4min,高压温度和时间分别为120℃和40min,最后在4℃冷藏24h,在此工艺条件下,马铃薯回生抗性淀粉制备的产率为9.03%。  相似文献   

2.
以新鲜玉米为原料,经过粉碎、糊化等工艺处理后,对酶解的工艺进行研究,分别测定玉米汁饮料在高温α-淀粉酶和糖化酶的不同酶解条件下的DE值,以确定2种酶最佳的工艺参数。通过感官评价的方法,进一步确定蔗糖和稳定剂的添加量,保证玉米汁饮料的最佳口感以及合适的稳定效果。结果表明,高温α-淀粉酶酶解玉米汁的工艺参数为加酶量20 U/g,酶解时间60 min,酶解温度80℃;糖化酶的酶解工艺参数为加酶量200 U/g,糖化时间5 h,糖化温度60℃。选择蔗糖添加量1.0 g/100 mL时,玉米汁饮料甜度适宜、口感清爽;选择黄原胶和CMC作为稳定剂,其中黄原胶添加量0.2%,CMC添加量0.1%达到较好的稳定效果。  相似文献   

3.
利用不同酶制剂对谷物杂粮粉进行水解,探讨酶解条件对谷物杂粮粉黏度的影响。结果表明,当谷物杂粮粉底物质量分数为5%,纤维素酶和中温淀粉酶配比为1∶1,pH值为7,酶解温度为50℃,酶解时间为90 min,此时谷物杂粮粉水解液的黏度为92.34 mPa·S,该酶解工艺条件制得的谷物杂粮粉黏性适中,口感最佳。  相似文献   

4.
为建立啤酒糟酶解物中低聚木糖HPLC-ELSD检测方法,将啤酒糟酶解物用纯水提取,色谱柱为COSMOSIL Sugar-D分析柱(250 mm×4.6 mm,5μm),流动相为乙腈-水(69:31,V/V),流速为0.9 mL/min,柱温40℃,进样量3μL,Evaporator Temperature为78℃,载气流速为1.6 L/min,载气压力为0.5 MPa,采用峰面积外标法定量检测低聚木糖含量。结果表明,木二糖~木五糖分别在0.024~0.245 mg/mL质量浓度范围内呈良好的线性关系,检出限分别为0.0245、0.0245、0.02425、0.024 mg/mL,定量限分别为0.0907、0.0907、0.08981、0.8889 mg/mL,RSD分别为0.203%、0.224%、0.233%、0.252%,样品加标回收率为97.31%~99.83%。该方法具有灵敏度高、重复性好等优点,可用于啤酒糟酶解物中低聚木糖的检测。  相似文献   

5.
酶解猪皮胶原蛋白制备抗氧化产物的研究   总被引:3,自引:0,他引:3  
以猪皮为原料,首先对猪皮胶原蛋白进行高温变性处理,再通过胃蛋白酶降解,用硫代巴比妥酸法(Thiobarbituric acid reactive substances assay,TBA法)评价酶解产物的抗氧化活性,并用SDS-PAGE电泳测定产物的分子量.结果表明,高温处理猪皮5 min,胃蛋白酶用量为底物的1.5%,酶解时间为0.5 h,酶解产物的抗氧化活性最强.但与抗坏血酸相比,酶解产物没有表现出还原能力.  相似文献   

6.
以蜜蜂蜂蛹为原料,研究蜂蛹蛋白质酶解工艺,并对所得结果进行分析。结果表明,胰蛋白酶水解蜂蛹蛋白质最适条件为:酶解温度为60℃,酶用量为1.5%,酶解时间1.5 h,pH值为8.0,料水比为1∶8,最适水解条件下,水解液中的氨基氮质量浓度为1.526 mg/mL;中性蛋白酶水解蜂蛹蛋白质最适条件为:酶解温度为45℃,酶用量为2.0%,酶解时间为1 h,pH值为7.5,料水比为1∶6,最适水解条件下,水解液中的氨基氮质量浓度为2.068 mg/mL;最优水解酶是中性蛋白酶;双酶水解蜂蛹蛋白质的最适条件为:总酶量为2.0%,酶量比为1∶2,酶解温度50℃,酶解时间为2 h,最适水解条件下,水解液中的氨基氮质量浓度为1.889 mg/mL。双酶同时水解的效果不及中性蛋白酶。  相似文献   

7.
用5种蛋白酶(木瓜蛋白酶、中性蛋白酶、typsin、pepsin以及Alcalase 2.4L)分别酶解金枪鱼头蛋白,以羟基自由基清除率为指标,筛选出羟基自由基清除力最强的是Alcalase 2.4L的酶解液,通过响应面试验优化Alcalase2.4L最佳酶解条件为:酶解时间340 min,酶解温度54℃,加酶量0.38%,该条件下酶解液的羟基自由基清除率最佳,为63.67%。  相似文献   

8.
论述了检测谷物及淀粉糊化特性的方法和电子旋转式粘度仪的总体结构、工作流程、设计要点和实验。研究表明:该仪器测定谷物及淀粉粘度性状,采用非牛顿流体粘度测量方法 (旋转式粘度),全面真实地反映谷物及淀粉糊化的实际情况,为GB/T 14490-2008《粮油检验谷物及淀粉糊化特性测定粘度仪法》的执行提供技术手段。  相似文献   

9.
对莲藕汁饮料的生产工艺进行研究,将莲藕经过清洗、去杂、切片、护色、打浆和糊化后,添加淀粉酶酶解淀粉后得到莲藕汁,添加白砂糖、苹果浓缩汁、梨浓缩汁、哈密瓜浓缩汁、黄原胶复配,经过均质、脱气、超高温瞬时杀菌和无菌灌装后,制备出莲藕汁饮料。通过单因素试验与正交试验确定了淀粉酶的种类和莲藕汁的酶解工艺,得到α-淀粉酶的最优酶解条件为α-淀粉酶添加量10 U/g,酶作用pH值6.0,酶处理温度75℃,酶解时间50 min;确定了莲藕汁复合饮料的最优配方为莲藕汁添加量70%,白砂糖添加量3%,梨浓缩汁添加量2%,苹果浓缩汁添加量2%,哈密瓜浓缩汁添加量2%。  相似文献   

10.
选用苦味胡麻油为试验原料,分别采用碱性蛋白酶、中性蛋白酶、酸性蛋白酶对苦味胡麻油进行脱苦。通过对脱苦胡麻油进行感官评价并测定胡麻油中苦味物质环八肽的含量,考察不同种类的酶、酶活力、酶解时间和酶解pH值对酶法胡麻油脱苦效果的影响。最后通过正交试验设计得到最佳的胡麻油脱苦条件组合为采用中性蛋白酶,酶活力45 U/mL,酶解时间6 h,酶解pH值7时,处理效果最好;最佳条件下可测得胡麻油中苦味物质环八肽的含量为13.6 mg/kg。  相似文献   

11.
Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.  相似文献   

12.
Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.  相似文献   

13.
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...  相似文献   

14.
Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.  相似文献   

15.
T. Visser  E. H. Oost 《Euphytica》1981,30(1):65-70
Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.  相似文献   

16.
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...  相似文献   

17.
Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.  相似文献   

18.
[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...  相似文献   

19.
E. Keep 《Euphytica》1986,35(3):843-855
Summary Cytoplasmic male sterility (cms) is described in the F1 hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf 1) and recessive for the other (Rf 2).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph 3(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf 1(one of two dominant additive genes controlling early season leafing out) indicated that Rf 1and Rf 2were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf 1, and 0.15 for Lf 1-Sph 3were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph 3.It is suggested that competitive disadvantage of lf 1-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph 3. Poor performance of lf 1- (and possibly lf 2-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).  相似文献   

20.
Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.  相似文献   

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