大豆糖蜜澄清工艺的研究

为了利用大豆糖蜜发酵生产单细胞蛋白,对大豆糖蜜的澄清工艺进行了研究。以除浊率和脱色率为指标,研究了稀释浓度、加酸种类、pH值、加热温度对大豆糖蜜澄清效果的影响。结果表明,加酸种类对澄清效果影响不显著,稀释浓度、pH值、加热温度对大豆糖蜜澄清效果影响显著。最佳澄清工艺条件为:在大豆糖蜜质量分数15%,用磷酸调pH值至3.5,在80℃恒温水浴30min,大豆糖蜜的除浊率为99.24%,脱色率为95.18%。     

香椿酸豆乳的研制

以香椿和大豆为原料,用嗜热链球菌和保加利亚乳杆菌发酵制备香椿酸豆乳,确定大豆的脱腥工艺;通过正交试验,确定香椿酸豆乳的工艺条件和配方:将2种乳酸菌按1:1混合后,按4%进行接种,豆乳制备料水比为1∶10,香椿汁添加量20%,蔗糖5%,葡萄糖2%,果胶0.2%,40℃发酵4h,可制得具有混合香味、各项指标均符合国家标准的香椿酸豆乳。     

匀浆法提取-高效液相色谱法测定烟草料液中苯甲酸·山梨酸

[目的]研究了匀浆法提取-高效液相色谱法测定烟草料液中的苯甲酸和山梨酸。[方法]用匀浆法提取料浸样品,然后采用WatersOasis（HLB固相萃取小柱预分离。以Waters-XbridgeShieldRP18（3.9×150mm,5μm）色谱柱为固定相,0.2%磷酸和乙睛为流动相,流速1.2ml/min。苯甲酸和山梨酸在10min内可达到基线分离,并采用紫外二极管矩阵检测器检测。[结果]方法标准回收率为92%～104%,相对标准偏差为2.8%～3.2%,结果满意。[结论]该研究方法重现性好,回收率较高,检出限较低,可用于烟草料液中苯甲酸和山梨酸含量分析的推广。     

不同水平大豆磷脂对泌乳奶牛生产性能的影响

为了研究日粮中添加不同水平大豆磷脂对泌乳早期奶牛生产性能的影响,选取产后30～40 d的中国荷斯坦奶牛48头,采用完全随机试验设计,按照日均产奶量和体重相近的原则分为4组,每组12头.I组为对照组,饲喂基础日粮,Ⅱ组、Ⅲ组、Ⅳ组分别在基础日粮中添加1.5％的大豆磷脂、2.5％的大豆磷脂和3.5％的大豆磷脂.结果表明:日...     

Growth Response of Tilapia Fed Diets Rich in High-Lysine Corn and Corn Gluten

Abstract

The purpose of this study was to find out if fish meal is necessary in tilapia diet for good growth response. Five experimental diets (32% protein) containing 46-51% high-lysine corn, 20% corn gluten meal, supplemented with soy grits and synthetic amino acids, with and without fish meal were formulated. The diets were fed to tilapia with average initial weight of 13 g for 70 days in aquaria. Weight gain expressed as percentage increase after 70 days or as grams/day, feed conversion ratio, and protein efficiency ratio were equal (P > 0.05) to a commercial feed (36% protein) for all experimental diets. It appears that 32% protein diets with 46-51% high-lysine corn and 20% corn gluten meal were adequate for tilapia based on weight gain, feed conversion ratio, and protein efficiency ratio, and that fish meal is not necessary for tilapia feed to obtain good growth response.     

Preliminary study on effects of methionine hydroxy analog and taurine supplementation in a soy protein concentrate‐based diet on the biological performance and amino acid composition of rainbow trout [Oncorhynchus mykiss (Walbaum)]

A feeding trial was conducted on the effects of methionine hydroxy analog (MHA) and taurine supplementation in diets with high levels of soy protein concentrate (SPC) on the growth performance and amino acid composition of rainbow trout, Oncorhynchus mykiss (Walbaum) comparing with fish meal based diet. The control diet had 520 g kg^?1 fish meal. In the methionine deficient diets (5.1 g kg^?1), fish meal was replaced by 490 g kg^?1 of the SPC in the SPC49 diet. The SPC49 diet was supplemented with either MHA (6 g kg^?1) only or a combination of MHA and taurine (2 g kg^?1). Fish were fed isoproteic (460 g kg^?1) and isolipidic (130 g kg^?1) diets for 12 weeks. Growth performance (i.e. weight, feed conversion ratio, and thermal‐unit growth coefficient) was inferior in fish fed the SPC49 diet. MHA supplementation improved growth performance (P < 0.05). No difference was observed when taurine was added to the SPC49 and MHA diet (P > 0.05). Whole‐body taurine contents increased with taurine supplementation, whereas plasma methionine increased with MHA supplementation (P < 0.05). In conclusion, the substitution of fish meal with SPC supplemented with MHA did not negatively impact growth, and the addition of taurine did not improve growth performance in rainbow trout.     

不同比例番茄酱渣与苜蓿制成的草颗粒对绵羊瘤胃降解率的影响

选用3只安装有永久性瘤胃瘘管的绵羊,采用尼龙袋法对不同配比的番茄酱渣与苜蓿、棉壳制成的草颗粒在瘤胃2、6、12、24、36和72 h的降解率进行研究,从而确定了番茄酱渣与苜蓿、棉壳合适的制草颗粒配比和混合草颗粒中各营养成分的动态降解率。结果表明,番茄酱渣∶苜蓿∶棉壳为60∶35∶5时正组合效应最高,该组降解率:dp(DM)=27+40.9×(1-e^-0.0139t)(n=6,R²=0.978);dp(CP)=31.9+32.6×(1-e^-0.071t)(n=6,R²=0.986);dp(NDF)=14.3+56.1×(1-e^-0.023t)(n=6,R²=0.994)。     

纳豆激酶酱醪制作的可行性研究

[目的]研究纳豆激酶酱醪制作的可行性。[方法]通过整合纳豆激酶发酵工艺与酱油发酵生产工艺,使单次原料发酵产出2套产物,利用两者发酵原料的相同性,通过调整发酵条件实现2种发酵工艺的整合。[结果]该工艺成功制得含有纳豆激酶的酱醪。[结论]该研究证明整合纳豆激酶发酵工艺与酱油发酵生产工艺,单次原料发酵可以产出含有纳豆激酶的酱醪。     

涪陵榨菜酱油香气成分的GC-MS分析

[目的]初步分析涪陵榨菜酱油中挥发性香气成分,为其内在质量评价和鉴定提供特征数据。[方法]采用乙醚萃取法提取榨菜酱油中的香气成分,并用气相色谱-质谱联用仪（GC-MS）分析鉴定。[结果]鉴定出30多种化合物,其中主要成分是醇类、羧酸类、酯类、酮类、酚类以及杂环化合物（如呋喃类、吡嗪类、吡咯类）和一些含硫化合物等,它们对涪陵榨菜酱油的风味贡献较大。[结论]GC-MS分析方法明确了涪陵榨菜酱油中的挥发性香气成分,可以辅助用于其内在质量控制。     

不同卵黄成分、大豆卵磷脂及β-环糊精胆固醇对马精子冷冻效果的影响

本研究旨在比较添加不同浓度的卵黄成分（全卵黄（EY）、卵黄浆蛋白（EYP）、低密度脂蛋白（LDL）及水溶性卵黄蛋白（livetin））、大豆卵磷脂（SL）及β-环糊精胆固醇（CLC）对马精子冷冻效果的影响。选择4匹成年英纯血种公马进行采精,试验1：以INRA82+3.5%的混合抗冻剂作为基础冷冻液,添加0、2%、4%和8%浓度的EY、LDL、EYP或水溶性卵黄蛋白;试验2：以4%全卵黄组为对照,添加1%、2%和4% SL;试验3：在INRA82+3.5%的混合抗冻剂+4% EY基础液中添加0、0.75、1.5和3 mg/mL浓度的CLC。结果显示,EYP、LDL及水溶性卵黄蛋白3种卵黄组分均对马精子冷冻具有显著保护作用（P<0.05）,但不同卵黄组分之间及与EY组相比保护效果无显著差异（P>0.05）;添加低浓度（1%）的SL精子冻融后活力与对照组（4% EY组）相比无显著差异（P>0.05）,但添加高浓度SL组（2%和4%）冻融后精子TM、PM及RAP值均显著低于对照组（P<0.05）;添加不同浓度的CLC解冻后精子活力与未添加组无显著差异（P>0.05）。研究结果表明,卵黄中EYP、LDL和水溶性卵黄蛋白均对精子保护有效,保护效果与EY无显著差异;1% SL可获得与卵黄相似的保护效果;在含有卵黄的基础冷冻液中添加CLC未能提高精子冻后活力。