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1.
建立并优化了测定王草青贮饲料中乳酸(LA)、乙酸(AA)、丙酸(PA)、丁酸(BA)的高效液相色谱检测方法.采用20 mmol/L NaH2PO4/H3PO4(pH2.65)-甲醇二元梯度洗脱程序在高效液相色谱-紫外检测器上完成4种有机酸的定性定量分析.结果表明,4种有机酸在0.015~2.25 mg/mL范围内的线性关系较好,相关系数R2≥0.999 4,精密度、稳定性的RSD均小于5%,样品回收率在88.44%~114.51%,LA、AA、PA、BA的检出限分别是1.40、3.31、3.57、5.23 μg/L.该方法简单、准确、重复性好,可用于王草青贮饲料中有机酸测定.  相似文献   

2.
混合盐碱胁迫对高粱幼苗的影响   总被引:46,自引:0,他引:46  
用50,100,200,300mmol/L含有不同比例NaCl,Na2SO4,NaHCO3和Na2CO3的混合盐溶液对高粱(Sorghum bicolor L.)幼苗进行混合盐碱胁迫处理。测定高粱幼苗存活率、相对生长率、相对含水量、相对根系活力以及电解质外渗率等胁变指标。结果表明:上述各项胁变反应均随盐浓度和碱性盐比例增加而加剧,由碱性盐造成的高pH所致的胁变效应与盐浓度之间相关:即低盐度时pH作用较小,随盐度增大其作用加剧。在碱胁迫较弱时胁变主要受盐度影响,随碱胁迫增大pH成为影响胁变的主要因素。在高盐高碱条件下,盐胁迫与碱胁迫间具有协同作用。  相似文献   

3.
选择4种中性盐(NaCl、KCl、Na2SO4和K2SO4)和4种碱性盐(Na2CO3、NaHCO3、K2CO3和KHCO3),设置0mmol/L(对照)、50mmol/L、100mmol/L、150mmol/L和200mmol/L5个浓度,借助InfoStat软件中DGC方差分析法,分析了盐类型和浓度对普通玉米种子发芽率和幼苗生长的影响。结果表明,盐胁迫延缓了玉米种子的发芽时间,且随着盐浓度增加胁迫作用增强。硫酸盐对幼苗生长的胁迫作用大于氯盐,钠盐大于钾盐,碳酸盐大于硫酸盐,二价盐大于一价盐,碱性盐大于中性盐。  相似文献   

4.
不同盐分胁迫对野生大豆种子发芽的影响   总被引:2,自引:0,他引:2  
一年生野生大豆是栽培大豆的野生近缘种和基因资源,具有耐盐碱、抗寒、抗病等优良性状.研究其种子萌发的耐盐性,为利用盐碱地资源和野大豆的引种驯化供依据.以山东德州一年生野大豆为材料,研究NaCl、Na2SO4、Na2CO3及三者的混合盐的胁迫对野大豆种子的发芽率、发芽势、发芽指数及胚生长的影响.随盐溶液浓度的增加,野大豆种子的发芽率、发芽速度、发芽指数均呈下降趋势,而低浓度的Na2SO4(10~50 mmol·L-1),Na2CO3(0~10 mmol·L-1)促进种子萌发,高浓度的NaCl(>200 mmol·L-1)、Na2SO4(≥200 mmol·L-1)、Na2CO3(≥75mmol·L-1)抑制种子萌发;10 mmol·L~Na2SO4处理下,其胚根胚轴长度都大于未经盐处理的,低浓度的盐分促进了胚根和胚轴的生长.结果表明低浓度的盐分促进一年生野生大豆胚的生长,野生大豆的胚根比胚轴对盐分更敏感.  相似文献   

5.
对木薯品种(系)SC8、南植199、C869、D346和E632在6~11个月生长期的块根淀粉糊化特性进行研究。结果表明,木薯的含粉量随生长期的延长呈先增后减趋势,不同品种的变化拐点各不相同;直链淀粉含量随生长期变化趋势因品种而异,表现出显著的品种效应和生长期差异性;峰值粘度在生长期为8个月后随生长期的延长而增加,其值与鲜薯含粉率、直链淀粉含量呈显著正相关关系;木薯淀粉糊化温度的生长期差异性显著,且变化趋势因品种的差异而略有不同,它与直链淀粉含量呈显著负相关关系。木薯淀粉恩氏粘度与直链淀粉含量呈显著正相关。  相似文献   

6.
不同木薯品种(系)块根淀粉特性研究   总被引:10,自引:1,他引:10  
古碧  李开绵  李兆贵  李凯 《热带作物学报》2009,30(12):1876-1882
对79个木薯品种(系)块根淀粉的鲜薯含粉率、原淀粉水分、直链淀粉和支链淀粉含量、峰值粘度、糊化温度、透明度、恩氏粘度、淀粉粒直径和表面积等淀粉特性指标进行研究.结果表明,不同木薯品种(系)各淀粉特性指标存在很大的差异,不同指标间也有一定的相关性,利用主成分分析对各品种(系)各指标进行综合分析,认为E169、C766、E1424、E339、R72、E217、E344、E232、E316和桂热3号木薯淀粉的加工特性最好,更适合木薯淀粉的深加工.  相似文献   

7.
不同木薯/花生模式下的产量表现及其经济产出研究   总被引:3,自引:0,他引:3  
研究了4种木薯株行距配置0.8 m×0.8 m(M_1)、0.6 m×1.0 m(M_2)、0.8 m×(1.0 m+0.6 m)(M_3)、0.6 m×(1.0 m+0.8 m)(M4),木薯单作与相应木薯/花生体系的产量表现和经济产出的影响。结果表明:4种间作处理的土地当量比(LER)和产值当量(VOE)均大于1,木薯实际产量亏损(AYLc)均大于0,木薯偏土地当量比(PLER-C)均高于木薯在间作和单作中所占的土地面积之比,即4种间作模式均能提高土地利用率,且对木薯来说均具有间作优势;M3间作处理中花生相对于木薯的竞争力(Apc)和花生实际产量亏损(AYLp)大于0,而经济产出则比M3单作木薯高出了237元/667 m2,总的实际产量亏损(AYL)为1.07,在4种间作处理中数值最大。故木薯/花生间作体系中M3木薯株行距配置的间作产量优势和经济效益优势最佳。  相似文献   

8.
内生解淀粉芽孢杆菌TB2液体发酵条件的研究   总被引:3,自引:0,他引:3  
采用单因素试验和正交试验对具有广谱拮抗作用的内生解淀粉芽孢杆菌TB2菌株的摇瓶发酵培养基和发酵条件进行优化。结果表明,最佳培养基组份为:玉米淀粉1.0%、豆粉1.0%、(NH4)2SO40.5%、MgSO4·7H2O0.1%、FeSO4·7H2O0.03%、K2HPO4·3H2O0.02%、KH2PO40.01%;培养条件为:初始pH值为7.5,温度35℃,接种量3%,装液量50mL/250mL三角瓶,摇床转速200r/min,发酵周期22~26h。优化条件下发酵水平活菌数达到8.52×1010cfu/mL。  相似文献   

9.
振荡发酵生产球形细菌纤维素   总被引:2,自引:0,他引:2  
采用振荡发酵生产球粒形细菌纤维素,以提供外观和口感新颖独特的纤维素产品.结果表明:培养基的碳源浓度、椰子水添加量、装瓶量、振荡速度等对纤维素颗粒的形状、产量影响较大.最佳发酵工艺为:15g/L蔗糖,(NH4)2SO43 g/L,KH2PO43g/L,MgSO4·7H2O 0.2 g/L,酵母粉0.5 g/L,20%(ν/ν)椰子水,20%(ν/ν)菠萝汁,500mL三角瓶装200mL发酵液(液高3.4 cm),初始pH4.5,150 r/min,30℃振荡培养10d.在此条件下,可得到粒形均匀(φ 0.8~1.0 cm)、产量较高(3.15 g/L)的球形细菌纤维素.这种新型纤维素球粒能满足食品工业和消费者多元化的需求.  相似文献   

10.
为探讨盐碱胁迫下亚麻幼苗阳离子吸收和分配的特点,为盐碱地种植亚麻栽培技术提供理论指导。采用2种中性盐(Na Cl和Na2SO4)和2种碱性盐(Na HCO3和Na2CO3)分别混合模拟盐胁迫和碱胁迫,对中亚麻2号进行14天胁迫处理,测定了苗长、根长和茎长等生长指标,并分析了根系和地上部Na+、K+、Ca2+、Mg2+含量的变化。结果表明:(1)盐碱胁迫不同程度抑制了亚麻幼苗的生长,碱性盐胁迫比中性盐胁迫的抑制更严重。中性盐胁迫对亚麻茎的抑制较根更严重,而碱性盐胁迫则得到相反的结果。(2)盐碱胁迫大幅度增加了亚麻苗期根和地上部对Na+的吸收。中性盐胁迫下地上部K+的吸收增高,根的K+吸收降低。碱性盐胁迫下根和地上部K+的吸收均降低。中性盐胁迫和碱性盐胁迫下根和地上部Ca2+和Mg2+的吸收均降低,根系中的降低程度较地上部大。(3)相关性分析表明盐碱胁迫下Ca2+的吸收与Na+的吸收呈极显著负相关。  相似文献   

11.
为了解食品添加剂时南阳彩色小麦淀粉糊特性的影响,采用Brabender黏度仪,测定南阳彩色小麦淀粉在添加不同碱面、明矾、食盐和葡萄糖后的黏度曲线.研究了这些因素对小麦淀粉糊化特性的影响.结果表明,四种添加剂均使淀粉的糊化温度升高.随着碱面和明矾浓度的增加,淀粉糊的峰值黏度、最终黏度、消减值、回生值显著降低,崩解值显著升高,淀粉糊的热稳定性降低,凝胶性和凝沉性减弱;而葡萄糖和食盐的加入使淀粉的消减值、回生值和最终黏度升高,增强了淀粉糊的凝胶性和凝沉性.总体来看,碱面和明矾对南阳彩色小麦淀粉糊化特性的影响较大,葡萄糖和食盐的影响较小.碱面、明矾、葡萄糖和食盐的适宜添加量分别为0.4%、0.5 %、5.0%和2.0%.  相似文献   

12.
Changes in pH, titratable acidity and mineral content (Ca, Fe, Mg, Zn) were estimated in processed cassava products while the mineral content of raw and blanched amaranthus vegetable was determined. pH of fresh cassava (6.5) decreased as total organic acid (0.07%) increased with fermentation period. Fufu and lafun had the lowest pH and the highest total organic acids contents. Fermentation of cassava increased the total calcium and iron contents, reduced magnesium level while zinc remained fairly constant in grated cassava but was reduced when soaked in water (for the preparation of fufu and lafun). Fermentation also increased the availability of these selected minerals in both cassva products and simulated cassava-vegetable diets. Blanching reduced the mineral content of amaranthus vegetable but increased mineral availability. Fermentation of cassava and blanching of vegetables play an important role in making minerals more available and these processing methods should be encouraged to potentially ameliorate the disease states associated with mineral deficiency.  相似文献   

13.
In this paper, chitosan was suggested for using as a replacement for sodium alginate in the pretreatment print paste for digital ink-jet printing for cotton fabric. Pretreatment print pastes prepared from the mixture of chitosan and acetic acid with the appropriate viscosity gave satisfactory prints on the cotton fabric. Chitosan-treated cotton fabrics were digitally irk-jet printed with four different colors and the color fastness rating of the printed fabrics was satisfactory. Experimental results revealed the possibility of pre-treating the cotton with chitosan to replace the sodium alginate normally present in the pretreatment print paste recipe.  相似文献   

14.
为研究不同木薯品种的鲜食加工适宜性,以12份食用品种(系)为材料,加工成蒸木薯、木薯汁、木薯羹进行品质特性鉴定和感官评价,应用相关性分析和主成分分析等手段综合评价各品种(系)适宜性,分析其主要影响因子。结果表明,15个蒸木薯品质评价性状共提取了5个主成分,色度值a*、色度值b*、纤维感、综合评价、弹性、硬度和胶着性起主要作用;10个木薯汁品质评价性状提取了3个主成分,色泽、组织状态、pH和黏度共4个性状起主要作用;5个木薯羹感官评价性状共提取了2个主成分,感官综合评价和面度共2个性状起主要作用。另外,蒸木薯主要品质评价指标受到鲜薯淀粉、干物质、粗纤维和蛋白质含量的影响,木薯汁主要品质评价指标受鲜薯蛋白质、可溶性糖和直链淀粉含量的影响。12个品种(系)中P3适宜作为水果木薯,M33、M9、ST、NK-10适用于蒸木薯,ST、P9、M11、P3适宜作为木薯汁加工原料,M9、M11、ST、NK-10适宜作为木薯羹加工原料。  相似文献   

15.
以自育品系香稻1601为材料,研究不同氮肥追施量对其品质和淀粉RVA谱特征值的影响,为探明氮肥施用量与香稻品质关系提供数据支撑。试验结果表明:随着氮肥追施量的增加,稻米蛋白质含量增加,食味品质下降趋势,淀粉RVA谱曲线整体下降,峰值黏度、热浆黏度、冷胶黏度均呈下降趋势,崩解值和消减值先升高后降低,糊化温度和峰值时间无显著差异。相关分析表明,峰值黏度和冷胶黏度与大米蛋白质含量极显著负相关,相关系数-0.889和-0.843,与食味值存在极显著或显著正相关,相关系数0.896和0.763。  相似文献   

16.
木薯全粉的功能特性   总被引:2,自引:0,他引:2  
开发推广木薯源大宗食物,充分发挥木薯的资源优势,拓展人们日常消费的食物资源,积极应对日益严重的粮食危机.通过对木薯全粉与鲜木薯、木薯淀粉中的营养成分的测定对比,及对木薯全粉的黏度特性、透光率、膨胀度等进行分析,并对木薯全粉的营养成分保留及功能性质进行评价,探讨木薯全粉在食品工业中的潜在应用范围.结果表明,木薯全粉相对于鲜木薯、木薯淀粉营养成分保持良好,食用安全,同时具有较好的加工性能,在食品工业中应用前景广阔.  相似文献   

17.
This study determined the effects of stearic acid on the functional properties of teff starch, a compound granule starch in comparison to maize, a simple type granule starch. Stearic acid was incorporated into teff and maize starches and pasted (held for 5 or 120 min at 91 °C) with an RVA (Rapid Visco Analyser). Teff starch with added stearic acid (0.25 and 1.5% starch basis) did not produce a pasting peak viscosity within short holding time (5 min) compared to maize starch. The paste viscosity of both teff and maize starches with stearic acid increased by about three times with long pasting (120 min). This increase in paste viscosity occurred earlier for teff starch than maize starch. Teff starch with stearic acid was more viscous and was non-gelling. Confocal laser scanning microscopy showed that stearic acid did not diffuse in teff starch granules, but seemed to coat them. However, stearic acid diffused inside maize starch granules through channels. This microstructural difference may explain the different pasting behavior. The early high paste viscosity and non-gelling properties of the teff starch modified with stearic acid could have promising applications in foods, for example better mouthfeel with lower starch concentration.  相似文献   

18.
为了改善木薯叶青贮品质,研究有机酸对木薯叶青贮品质及营养成分的影响,以确定青贮木薯叶最适合的有机酸种类及添加量。本研究以华南7号木薯幼嫩茎叶为原料进行青贮试验,设对照组、甲酸(0.2%)、乙酸(0.2%)和丙酸(0.2%)处理组,30 d后测定木薯叶青贮饲料pH、乳酸(LA)、乙酸(AA)、丙酸(PA)和丁酸(BA)含量以及主要营养成分含量。结果表明,木薯叶直接青贮品质较差,添加有机酸处理与对照相比显著降低青贮饲料的pH和丁酸含量(P<0.05),降低中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量(P<0.05),提高了饲料相对值(RFV)。添加有机酸可以改善木薯叶青贮品质并提高营养价值,添加乙酸(0.2%)和丙酸(0.2%)青贮品质较好,可作为木薯叶青贮添加剂。  相似文献   

19.
Changes of RVA viscosity and texture properties of waxy rice (n=9) and non-waxy rice (n=10) were analyzed through protein removal or disulfide bond disruption. Protease or DTT had similar effects on the pasting behavior of the waxy rice, but affected differently that of non-waxy rice. For all waxy rice flour treated with DTT or protease, the peak, breakdown and consistency viscosity values all significantly decreased, and the viscosity curves barely rose from the baseline. Pre-incubation of flours with a protease increased RVA pasting temperatures, decreased viscosities along all the points of the curves and the slopes of the linear parts of the curves for all non-waxy cultivars. DTT decreased RVA pasting temperatures and peak viscosities of all non-waxy flour, but increased breakdown viscosities in six non-waxy rice cultivars. With DTT-added cooking water, the hardness of cooked waxy and non-waxy rice, as determined by Instron, generally decreased. With DTT-added cooking water, the adhesiveness of all cooked waxy rice significantly decreased, while it increased significantly or remained the same in all cooked non-waxy rice. The above results indicated that the protein agent of a network linked by disulfide bonds increased the RVA gelatinized paste rigidity, the hardness and adhesiveness of cooked rice of all waxy cultivars, while in non-waxy cultivars, both the network and the increase of the gelatinized paste concentrations resulting from protein hydration contributed to the enhancements of the RVA paste rigidity and the cooked rice hardness.  相似文献   

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