直接发酵法提取苜蓿叶蛋白

研究直接发酵法提取苜蓿叶蛋白的工艺,试验测定乳酸菌数,发酵时间和发酵温度等单因素的不同水平对苜蓿叶蛋白提取率的影响,并在单因素试验的基础上进行三因素四水平正交试验,优化提取工艺.试验结果表明各因素对苜蓿叶蛋白提取率的影响顺序为:发酵温度>乳酸菌数>发酵时间,最佳工艺参数为:1 mL苜蓿汁液接种乳酸菌107个,将汁液在34℃密闭发酵8 h;深化了对直接发酵法提取叶蛋白工艺的研究,为生产实践提供理论依据.     

青贮苜蓿及不同添加水平的苜蓿草粉对初产母猪繁殖性能、初乳成分及其仔猪生长性能的影响

在初次妊娠母猪的日粮中分别添加10%青贮苜蓿或10%、15%、20%的苜蓿草粉,探讨了青贮苜蓿及不同添加水平的苜蓿草粉对初产母猪繁殖性能、初乳成分及其仔猪生长性能的影响。结果表明:与对照组相比,各试验组母猪在妊娠期背膘厚度增加量和哺乳期背膘厚度损失量上均无显著差异;各苜蓿草粉组在初生仔猪总数、产活仔数、产活仔率、仔猪的断奶重等指标上均有所上升;15%、20%苜蓿草粉组母猪初乳的乳脂率显著升高(P<0.05);各试验组母猪初乳中的乳总固形物含量显著升高(P<0.05)。在不同处理中,以20%苜蓿草粉添加组的综合效果最为理想。     

苜蓿的深加工

具有“牧草之王”美誉的苜蓿以其适应性强、产量高、适口性好且含有丰富的粗蛋白、矿物质及多种维生素 ,作为一种优良饲草已广泛用于养殖业并被大力开发种植。现在不但苜蓿菜肴已摆上餐桌 ,深受食客欢迎 ,而且苜蓿在深加工方面也取得了一定的进展。1　提取食用叶蛋白食用叶蛋白     

苜蓿的营养特点及对反刍动物作用机理的研究

对苜蓿的营养价值和苜蓿对反刍动物作用机理的研究进行了概述。苜蓿草具有较高的营养价值,反刍动物饲喂苜蓿能提高DMI,促进瘤胃发酵和乳牛的泌乳性能,尤其能提高奶中共轭亚油酸的含量,对体液指标影响不大。指出了今后如何在饲料中合理搭配苜蓿草来提高氮的利用率,以及苜蓿草的贮藏加工的研究重点。     

苜蓿叶蛋白研究概述

本文从苜蓿的分布,国内外苜蓿叶蛋白研究进展,用于提取叶蛋白的原料、提取原理、提取方法等方面对苜蓿叶蛋白产业做了较全面的介绍,并对苜蓿叶蛋白产业面临的问题进行分析,对该产业的前景做出展望.     

乙醇纯化苜蓿叶蛋白效果初探

本文应用有机溶剂法对苜蓿叶蛋白的提取纯化方法进行了比较研究.结果表明:通过85℃直接加热法提取的苜蓿叶蛋白,经乙醇处理提纯后,蛋白提纯率达49.2%,蛋白质含量高达89.4%;苜蓿叶蛋白产品品质明显提高,草青味消失,颜色为浅绿色.     

美国的苜蓿种子产业

在美国,被誉为“牧草王后”的苜蓿是种植面积仅次于玉米、小麦和大豆的第四大作物,与前三大作物主要收获子实不同,种植苜蓿主要是为了收获商品干草。粗略统计,苜蓿干草的年产值达81亿美元,其中苜蓿草粉和方草捆的年出口额达5 000万美元,如果把苜蓿与其他牧草混播草地生产干草的产值计算在内,整个苜蓿干草产业创造产值近100亿￣135亿美元。 一、发展历程1847—1850年由加利福尼亚州第一次从南美洲将苜蓿引进美国西部地区以来,美国苜蓿种业的发展大致可以划分为四个时期:1郾种源混杂期(1900—1925) 随着畜牧业的发展,美国中部、东部、东北等土…     

苜蓿高水分打捆人工继续干燥条件的优化

【目的】筛选高水分苜蓿草捆最适的人工辅助干燥条件,为克服第二、三茬苜蓿收获易受雨淋且叶片损失严重的问题提供技术支持。【方法】选择影响高水分打捆人工辅助干燥苜蓿品质的水分、密度、摆放间距和人工辅助干燥方式4个因素,设计L9(34)正交试验,对上述条件下高水分苜蓿草捆的发霉情况、营养物质进行分析,对不同处理条件下苜蓿的相对饲用价值和经济价值进行测算,确定苜蓿高水分打捆人工继续干燥的最佳条件。【结果】通过试验对比分析第2组处理蛋白质和相对饲用价值分别为17.13和153.62,显著或极显著高于其他各组,为最优处理。根据正交试验极差分析结果可知,各因素对高水分打捆苜蓿品质影响的大小顺序为:人工辅助干燥摆放方式密度水分。【结论】高水分苜蓿草捆在水分为30%~35%、密度为120kg/m3、摆放间距20cm、2台鼓风机每日鼓风干燥3h的条件下继续干燥,所得苜蓿草捆的品质最佳。     

苜蓿叶绿素微波萃取的最佳工艺条件

以紫花苜蓿为原料,采用微波萃取法提取苜蓿中的叶绿素,以苜蓿草粉目数、乙醇浓度、辐照时间、复水时间、物料比、微波功率作为影响因素进行单因素试验,通过分析确定了单因素的最佳试验条件.采用L16(45)正交试验设计优化苜蓿叶绿素的提取工艺,结果表明:乙醇含量70%、辐照时间20 s、复水时间1 h、物料比1/20为最优工艺条件,苜蓿叶绿素的提取率可达2.038 mg/g.     

美国的苜蓿种子产业

在美国,种苜蓿主要是为了收获商品干草。粗略统计,苜蓿干草的年产值达81亿美元,其中苜蓿草粉和方草捆的年出口额达5000万美元,如果把苜蓿与其他牧草混播草地生产干草的产值计算在内,整个苜蓿干草产业创造产值近100亿～135亿美元。1.品种培育。美国的苜蓿育种可以追溯到1897-190     

饲料蛋白质在鸡消化道食糜中肽氨基酸含量与氨基酸消化率的关系

通过2个试验研究了饲料蛋白质在鸡消化道食糜中肽氨基酸含量与氨基酸消化率的关系。试验1研究了3月龄黄羽肉鸡对鱼粉、豆粕、棉籽粕、菜籽粕的氨基酸利用率。试验结果，几种蛋白质饲料的氨基酸消化率分别为：鱼粉0．92，豆粕0．87，棉粕0．75，菜粕0．76。试验2研究了鱼粉、豆粕、棉籽粕、菜籽粕在鸡消化道各段（胃、十二指肠、空肠）食糜中肽氨基酸（PAA）的含量，并探讨了氨基酸消化率与肽氨基酸含量之间是否存在相关性。试验结果，不同蛋白质饲料在胃肠道食糜中肽氨基酸含量存在着很大差异 ，鱼粉最高，豆粕其次，棉籽与菜籽最低。将氨基酸消化率与肽氨基酸含量进行相关分析表明：二者之间存在明显相关性，其中以6h时间点的空肠段肽氨基酸含量与氨基酸消化率之间相关最高，R^2=0.98。     

聚合草叶蛋白的提取及饲用价值评价研究

以聚合草为材料,研究其叶蛋白提取的最佳条件及其氨基酸组成,并采用氨基酸评分(AAS)及必需氨基酸指数(EAAI)2种方法对其饲用价值进行评价.结果表明:影响聚合草叶蛋白(LPC)提取率的因素依次为凝絮方法＞固液比＞加盐量,最佳条件组合为65%乙醇沉淀、固液比1∶7、含盐量0.3%.聚合草叶蛋白氨基酸总量19.65%,必...     

Analysis of Amino Acid Composition and Six Native Alfalfa Cultivars

【Objective】 Six domestic alfalfa cultivars (Zhongcao No.3, Gannong No.1, Longmu No. 806, Zhongmu No.2, Xinjiang Big Leaf, Gongnong No.1) were used, amino acid content and the nutrition evaluation of alfalfa were studied, to provide the scientific basis for utilization and further research on native alfalfa germplasm resources or alfalfa resources development and utilization. 【Method】 Randomized block design with three replications was used. Different cultivars were planted in different experimental plot, the experimental plot area was 30 m ². The first year, first cut alfalfa which in the early flower stage were used. After 20 min heated at 105℃ and 48 h heated at 65℃, alfalfa were smashed to pass through a screen of 60 meshes. The samples were hydrolyzed by HCl and analyzed by automatic amino acid analyzer. Amino acid constituents and contents were analyzed. Alfalfa essential amino acid composition were compared with FAO/WHO amino acid pattern spectrum and FAO/WHO ideal protein standards. Ratio of essential amino acid (RAA), ratio coefficient (RC), score of RC (SRC) or essential amino acid index (EAAI) were calculated to evaluate the nutritional value. 【Result】 All of six domestic alfalfa cultivars contained 17 amino acids, 7 essential amino acids and 9 medicinal amino acids. Except Asp, Cys, Pro, F and (S+F)/B were significant difference among six cultivars, other amino acids compositions had no significant differences. The content of total amino acids in alfalfa were ranged from 14.85% to 19.48%, essential amino acids were range from 5.35% to 6.93%, non-essential amino acids were range from 9.50% to 12.55%, medicinal amino acids was greater than 60%. The content of total amino acids, essential amino acids and non-essential amino acids were highest in Xinjiang Big Leaf alfalfa. The ratio of sweet and fresh taste to bitter taste amino acid was above 1.8. Only Met+Cys were lower than FAO/WHO amino acid pattern. E/T was ranged from 35% to 36% and E/N was ranged from 54% to 57%, which were a little lower than FAO/WHO ideal protein standards. SRC was ranged from 73 to 74, and EAAI of all alfalfa was closed to 1. 【Conclusion】 There were abundant species and high content amino acid in alfalfa. The essential amino acids were relatively balanced and reasonable. Alfalfa were good protein sources, which also has medicinal value. The first limiting amino acid was Met+Cys. When used as vegetables, it is recommended that something which has high content of Met+Cys were used as complementary food to improve their nutritional value.     

6个紫花苜蓿品种氨基酸组成分析及营养价值评价

【目的】选择我国培育的中草3号、甘农1号、龙牧806、中苜2号、新疆大叶、公农1号等6个紫花苜蓿品种为试验材料,通过氨基酸组分的分析及含量的测定,综合评价紫花苜蓿蛋白质营养价值,为深入研究和开发利用我国紫花苜蓿资源提供科学依据。【方法】采用随机区组设计,将不同品种紫花苜蓿分别种植于不同试验小区,小区面积为30 m ²,重复3次。试验样品为当年种植的第一茬于初花期刈割的苜蓿,每个小区随机选3行,刈割后105℃杀青20 min,65℃烘干48 h,粉碎过60目筛。采用盐酸水解法,使用氨基酸全自动分析仪测定17种氨基酸含量,分析不同氨基酸含量及组分。通过与FAO/WHO氨基酸模式谱和FAO/WHO理想蛋白质标准比较,通过计算紫花苜蓿必须氨基酸比值（RAA）、必须氨基酸比值系数（RC）、必须氨基酸比值系数分（SRC）和必需氨基酸指数（EAAI）,综合评价紫花苜蓿蛋白质的营养价值。【结果】我国培育的6个紫花苜蓿品种均含有被测的17种氨基酸。6个紫花苜蓿品种除天冬氨酸（Asp）、半胱氨酸（Cys）、脯氨酸（Pro）、鲜味氨基酸（F）的含量以及酸鲜甜氨基酸与苦味氨基酸比值（(S+F)/B）有显著差异外,其他氨基酸含量差异不显著;紫花苜蓿总氨基酸含量为14.85%—19.48%、必需氨基酸的含量为5.35%—6.93%、非必需氨基酸含量为9.50%—12.55%,其中新疆大叶紫花苜蓿总氨基酸含量、必需氨基酸含量和非必需氨基酸含量高于其他品种;紫花苜蓿含有9种药效氨基酸,药效氨基酸占总氨基酸的60%以上,甘农1号、新疆大叶和公农1号紫花苜蓿的药效氨基酸含量高于其他3个品种;紫花苜蓿酸鲜甜味氨基酸含量与苦味氨基酸含量比大于1.8。除了蛋氨酸+半胱氨酸含量低于FAO/WHO氨基酸模式谱外,其他几种氨基酸含量均高于FAO/WHO氨基酸模式谱。6个紫花苜蓿品种必需氨基酸占氨基酸总量的比值（E/T值）在35%—36%之间,必须氨基酸与非必须氨基酸的比值（E/N值）在54%—57%之间,E/T值和E/N值均略低于FAO/WHO理想蛋白质标准。6个紫花苜蓿品种的必须氨基酸比值系数分SRC值在73—77之间,必需氨基酸指数EAAI值均接近1。【结论】紫花苜蓿氨基酸种类齐全,总氨基酸含量较高。必需氨基酸齐全,相对均衡合理,接近人体氨基酸比例。口感好,营养价值高,为可食用优质蛋白源,并具有一定的药用价值。紫花苜蓿第一限制氨基酸为蛋氨酸+半胱氨酸,作为蔬菜食用时建议搭配蛋氨酸和半胱氨酸含量高的食品作为互补,以提高其营养价值。     

枸杞叶草粉营养价值的研究

枸杞叶是茄科枸杞属植物枸杞的茎叶,其活性成分和营养成分种类与枸杞子基本相同,具有较高的药用价值和营养价值。本文测定了枸杞叶草粉干物质、粗灰分、粗纤维、粗蛋白、粗脂肪、钙、总磷的含量,并与部分能量饲料、蛋白饲料和苜蓿草粉相应含量进行比较分析,研究其营养价值。结果表明:枸杞叶草粉干物质含量为90.98%,粗蛋白32.32%,粗脂肪1.10%,粗纤维7.8%,无氮浸出物34.76%,粗灰分15%,钙2.16%,总磷0.43%。其干物质含量高于能量饲料、蛋白饲料和苜蓿草粉,粗蛋白高于能量饲料和苜蓿草粉,粗脂肪低于三者,粗纤维含量介于蛋白饲料之间,无氮浸出物与蛋白饲料和苜蓿草粉相当,粗灰分和钙高于三者,总磷介于三者之间。综上所述,枸杞叶草粉具有较高的营养价值。     

Effect of graded levels of fiber from alfalfa meal on apparent and standardized ileal digestibility of amino acids of growing pigs

Two experiments were conducted to determine the effects of fiber level from alfalfa meal and sampling time on the apparent ileal digestibility(AID) and standardized ileal digestibility(SID) of amino acids(AA) in growing pigs. A total of 24 ileal-cannulated pigs(Duroc×(Large White×Landrace) with body weight(21.4±1.5) kg) were randomly allotted to 4 treatments. The pigs were provided a corn-soybean meal diet or a diet containing 5, 10 or 20% of alfalfa meal during two 10-d experimental periods. The AID of AA was measured. Six ileal-cannulated pigs were fed a protein-free diet in order to estimate the endogenous protein losses and SID of AA. Ileal AA digestibility was not affected by inclusion of 5 or 10% alfalfa meal in the diet(P0.05). The AID of His, Lys, Met, Phe, Thr, Val, Ala, Asp, Cys, Gly, Pro, Ser and Tyr reduced by 2.0–6.8% with the addition level of alfalfa meal(linear, P0.05). The SID of His, Lys, Ser, Thr and Tyr decreased by 2.2–4.3% as the level of alfalfa meal in the diet increased(linear, P0.05). The AID and SID of AA were not affected by the sampling time(P0.05). A multiple linear regression analysis, taking into account both the soluble and insoluble fiber content in the diets, explained more than 36% of variation in SID of Ser and Thr(P0.05). In conclusion, the corn-soybean meal diet containing 10% of alfalfa meal did not affect ileal AA digestion. The AID and SID of AA were similar between two sampling times. Increasing the concentration of total dietary fiber from 12.3 to 21.4% by adding graded levels of alfalfa meal(0–20%) to a corn-soybean meal control diet induced a linear reduction in AID and SID of most AA. Soluble and insoluble fibers from alfalfa meal have differential roles in the AA digestion, which may help explain the variation observed in the SID of partial AA. These findings would provide important information for dietary fiber level and composition related to AA digestion.     

紫花苜蓿品种氨基酸含量的特征性研究

本文对西北地区的１０种紫花苜蓿品种的氨基酸进行了分析．结果表明，礼县苜蓿、临洮苜蓿、永宁苜蓿的总氨基酸和必需氨基酸含量均较高；陇东苜蓿、会宁苜蓿、酒泉苜蓿的总氨基酸和必需氨基酸含量均较低；１０种紫花苜蓿品种的总氨基酸和必需氨基酸平均含量分别为１７．７５％和８．５１％：总氨基酸含量和必需氨基酸含量存在着极显著的正相关关系。所测试的苜蓿品种氨基酸含量具有特征性。     

Evaluation of Apparent Metabolic Energy,Nitrogen Corrected Metabolic Energy,Biological Value of Protein and Ileal Digestibility of Amino Acid of Yeast Hydrolysate for Broilers

【Objective】 The purpose of this study was to evaluate the apparent metabolic energy, nitrogen-corrected apparent metabolic energy, ileal apparent amino acid digestibility, standard ileal amino acid digestibility and total intestinal apparent amino acid digestibility of yeast hydrolysate in broilers, so as to provide the reference for the wide application of yeast hydrolysate in broiler diets. 【Method】 A total of 160 Cobb white-feathered broilers at 18 days old with no difference in body weight were randomly divided into the control group and experimental group. There were 8 replicates in each group, and 10 chickens with half male and half female were in each replicate. The control group was fed a nitrogen-free diet consisting of corn starch, glucose, fiber and soybean oil, and the experimental group was fed a semi-homozygous diet using yeast hydrolysate as the sole crude protein source. Furthermore, the control group and the experimental group were fed with 0.5% titanium dioxide, respectively, as an exogenous indicator. During the whole experiment, free feeding was available for broilers, feces were collected on 22-24 days using total fecal collection method, and the feed intake of broilers was counted. Further, the apparent metabolic energy of yeast hydrolysate and nitrogen-corrected apparent metabolic energy were calculated by measuring the total energy and nitrogen content in both diets and feces of broilers. After26 days of experiment, the latter half of ileum was dissected under anesthesia, the chime was taken out, and the contents of amino acids and titanium dioxide in both diet and ileal chyme were measured to calculate the apparent amino acid digestibility, standard ileal amino acid digestibility and total intestinal apparent amino acid digestibility of yeast hydrolysate. 【Result】 (1) The total energy value of yeast hydrolysate was 18.19 MJ·kg ^-1, the apparent metabolic energy value was 11.22 MJ·kg ^-1, and the nitrogen-corrected apparent metabolic energy was 10.17 MJ·kg ^-1. Effective energy was equivalent to that of common soybean meal. (2) Crude protein content of yeast hydrolysate was 41.7%, and total amino acid was 36.97%. The ratio of essential amino acid to dispensable amino acid was 44:56, which was close to that of common soybean meal. The limiting amino acids of yeast hydrolysate were Met, Met+Cys, Arg, Leu, Ile, Phe+Tyr, Val, His, lys, Thr and Trp, which were different from soybean meal. (3) The ileal apparent amino acid digestibility, standard ileal amino acid digestibility and total intestinal apparent amino acid digestibility of yeast hydrolysate were all higher than 70%. The available limiting amino acids were Met, Met+Cys, Arg, Leu, Ile, Thr, Phe+Tyr, His, Lys, Val, and Trp. Methionine and arginine were the first and the second limiting amino acids, and leucine and isoleucine were the third and the fourth limiting amino acids, respectively. Threonine was poorly available, and was regarded as the fifth restrictive available amino acid. In addition, the limiting amino acids of yeast hydrolysate were quite different to soybean meal. 【Conclusion】 Yeast hydrolysate was a kind of protein feed material. Its protein content and effective energy value were similar to soybean meal, but its amino acid composition and availability were quite different to soybean meal. Therefore, in the application of yeast hydrolysate in broiler diet, it was necessary to consider the need of supplementing different amino acids or mixing different protein feeds to balance amino acids.     

肉鸡酵母水解物代谢能及氨基酸可利用率评定

【目的】 评定肉鸡对酵母水解物的表观代谢能、氮校正表观代谢能、回肠表观氨基酸消化率、标准回肠氨基酸消化率、全肠道表观氨基酸消化率,拟为酵母水解物在肉鸡饲粮中的广泛应用提供基础参数。【方法】 选择18 d、体重无差异的科宝白羽肉仔鸡160只,随机分成对照组和试验组,每组8个重复,每个重复10只试验鸡,公母各半。对照组饲喂以玉米淀粉、葡萄糖、纤维、大豆油配制的无氮日粮,试验组饲喂以酵母水解物为唯一粗蛋白质来源的半纯合日粮,对照组和试验组均添加0.5%的二氧化钛作为外源指示剂。试验期间自由采食,全收粪法收集试验鸡22—24 d粪便,并统计该期间肉鸡采食量,通过检测日粮以及粪便中总能、含氮量来计算酵母水解物表观代谢能值和氮校正表观代谢能值。粪便收集完后自由采食,26日龄麻醉剖解收集回肠后半段食靡,分别检测日粮、回肠食糜中氨基酸及二氧化钛含量,计算酵母水解物回肠表观氨基酸消化率、标准回肠氨基酸消化率、全肠道表观氨基酸消化率。【结果】 （1）酵母水解物总能值为18.19 MJ·kg ^-1,表观代谢能值为11.22 MJ·kg ^-1,氮校正表观代谢能为10.17 MJ·kg ^-1,其有效能值与普通豆粕相当。（2）酵母水解物粗蛋白质含量为41.7%,总氨基为36.97%,必需氨基酸与非必需氨基酸之比为44﹕56,与普通豆粕接近;酵母水解物肉鸡限制性氨基酸依次为Met、Met+Cys、Arg、Leu、Ile、Phe+Tyr、Val、His、Lys、Thr、Trp,与豆粕差异较大。（3）酵母水解物回肠表观氨基酸消化率、标准回肠氨基酸消化率、全肠道表观氨基酸消化率均大于70%,肉鸡可利用限制性氨基酸依次为Met、Met+Cys、Arg、Leu、Ile、Thr、Phe+Tyr、His、lys、Val、Trp,蛋氨酸、精氨酸为第一、第二限制性可利用氨基酸,亮氨酸、异亮氨酸为第三、第四限制性可利用氨基酸,苏氨酸可利用较差,为第五限制性可利用氨酸,酵母水解物限制性氨基酸与豆粕差异较大。【结论】 酵母水解物是一种蛋白饲料原料,其蛋白质含量、有效能值与豆粕相当,但其氨基酸组成及氨基酸可利用率与豆粕存在较大差异。因此,酵母水解物在肉鸡日粮中应用,需要考虑补充不同氨基酸或者搭配不同蛋白质饲料来平衡氨基酸的需要。     

去盲肠鸡和未去盲肠鸡测定饲料氨基酸消化率的研究

试验表明,玉米、豆粕用去盲肠鸡和正常鸡测出的氨基酸真消化率差异不显著;棉仁粕用未去盲肠鸡测定的氨基酸消化率显著高于去盲肠鸡测定的氨基酸消化率（Ｐ〈０．０５）;菜籽粕用正常鸡测定的氨基酸消化率显著高于用去盲肠鸡测定的消化率。因此,当测定玉米、豆粕氨基酸消化率时,可以使用去盲肠鸡也可用未去盲肠鸡进行测定;但测定棉仁粕、菜籽粕氨基酸消化率时,为了获得可靠合理的数值,应选用去盲肠公鸡来进行测定。