羧甲基纤维素钠和羟乙基纤维素对冷冻猪血豆腐品质的影响

为提高猪血豆腐在冷冻条件下的品质特性,以新鲜猪血为原料,添加羧甲基纤维素钠(carboxymethyl cellulose sodium,CMC-Na)和羟乙基纤维素(hydroxyethyl cellulose,HEC),研究其对冷冻猪血豆腐蒸煮损失、色差、质构及感官品质的影响。结果表明:CMC-Na和HEC添加量均为1.00 g/100 mL时,冷冻猪血豆腐的蒸煮损失比未添加CMC-Na和HEC分别降低69.65%、86.82%(P<0.05),质构特性中的硬度、弹性、咀嚼性比未添加CMC-Na和HEC分别提高41.01%、20.03%、83.43%(P<0.05),其色泽指标红度值和黄度值高于鸭血豆腐(P<0.05),感官上嫩度软硬适中、切面密实、几乎无气孔。因此,添加CMC-Na和HEC能提高冷冻猪血豆腐的品质特性。     

从猪血中提取血红素的研究

猪血是生猪屠宰加工过程中的主要副产物之一,我国拥有丰富的猪血资源,但利用却很少,造成宝贵资源的浪费。本文选用有机萃取剂丙酮提取猪血中的血红素,通过正交实验确定了提取纯化血红素的最佳条件:溶血时添加1.0倍蒸馏水、0.25倍乙醇及0.2倍的氯仿,分离血红素时加入4倍丙酮同时调pH2.0,结晶血红素时加1.4倍的1mol/L的NaAc并调pH5.0,此条件下,血红素提取率可达28.6%以上。     

海藻酸钠和羧甲基纤维素钠涂膜改善鲜切豇豆贮藏特性的比较分析

为了提高鲜切豇豆的品质,本文研究了海藻酸钠(0.6%,m/m)和羧甲基纤维素钠(0.8%,m/m)两种涂膜剂对其贮藏期间的呼吸强度、维生素C、叶绿素等品质指标变化规律的影响。研究发现,与对照相比,在贮藏期间,海藻酸钠和羧甲基纤维素钠涂膜均有效降低鲜切豇豆的呼吸强度,维持较高的可溶性固形物含量,减少鲜切豇豆维生素C和叶绿素的损失,保持较高的过氧化物酶活性,减少丙二醛的积累。贮藏至12 d,海藻酸钠涂膜的鲜切豇豆呼吸强度为237.67 mg/(kg·h),处于较低水平;其维生素C、叶绿素及可溶性固形物含量分别比羧甲基纤维素钠涂膜的高13.06 mg/100 g、0.62 mg/g、0.49%,但丙二醛含量低11.36%。研究结果表明,海藻酸钠涂膜更有利于保持鲜切豇豆的品质及延长贮藏期,其用于豇豆的保鲜贮藏具有潜在的应用前景。     

不同胶体对碳酸饮料CO_2气容量的影响

研究羧甲基纤维素钠(CMC)、海藻酸丙二醇酯(PGA)、阿拉伯胶和瓜尔豆胶对碳酸饮料在储存和饮用过程中CO2气容量的影响。当碳酸饮料中含有相同质量分数(0.05%)的食用胶时,饮料开启后,CO2的释放速率由慢到快的胶体顺序为:CMC相似文献   

猪血亚硝基血红蛋白亚基色素的保存期限及其应用研究

以猪血和亚硝酸钠合成的亚硝基血红蛋白亚基色素为对象,通过光谱扫描、菌落总数测定和肉制品发色试验,研究色素在不同保存状态下的稳定性,以确定其保质期限。另外通过色差计测定该色素所制肉制品在贮藏期内的颜色变化,来判断色素发色的稳定性。结果表明:在-29℃冷冻条件下和采用真空冷冻干燥手段保存亚硝基血红蛋白亚基色素较为理想,保质期为6个月之久。而在肉制品贮藏期内,其色泽同样保持稳定,证实该色素添加到灌肠肉制品中是可行的。     

再生纤维素基交联改性纳滤膜的制备及对无机盐截留性能的研究

以竹纤维素再生膜为基膜,海藻酸钠和羧甲基纤维素的共混溶液为涂覆液,环氧氯丙烷为交联剂,采用交联法制备了一种新型纤维素复合纳滤膜。研究了纳滤膜的制备工艺和对NaCl、Na_2SO_4、MgCl_2、MgSO_4、CaCl_2(500 mg/L)的截留性能。结果表明,在海藻酸钠与羧甲基纤维素共混溶液质量分数2.0%、共混比1∶3、环氧氯丙烷质量分数3.0%条件下,纤维素复合纳滤膜的膜通量为13.75 L/(m~2·h),Na Cl截留率为48.15%,较纤维素再生膜的膜通量(487.81 L/(m~2·h))下降明显,较纤维素再生膜的截留率(1.52%)有明显提高。对几种无机盐的截留性能顺序为:Na_2SO_4﹥Mg SO4﹥Na Cl﹥Mg Cl2﹥Ca Cl2。相比纤维素再生膜,纤维素复合纳滤膜的抗张力为83.31 N,比纤维素再生膜的抗张力(46.65 N)提高了44.0%,膜伸长量4.7 mm,伸长率9.40%,抗张强度5.554 k N/m,机械性能相对提高。     

超声波法提取猪血液中血红蛋白的研究

本实验研究了超声波处理过程中水与红细胞体积比、超声功率、超声时间与间歇时间比以及工作时间等四个因素对血红蛋白提取率的影响,首先通过单因素试验初步确定各因素的范围,然后通过正交试验得出其最佳提取工艺参数。结果表明：水与红细胞体积比为4:1,超声功率为100W,超声时间与间歇时间比为1:1,工作时间为20min,血红蛋白提取率可达97.65%。     

Functional Properties of Heat Induced Gels from Liquid and Spray-Dried Porcine Blood Plasma as Influenced by pH

The properties of gels obtained from porcine blood plasma were studied under different pH conditions. Gels from liquid and spray-dried plasma were prepared and analyzed for water holding capacity (WHC), texture, and microstructure at pH 7.4, 6, 5.5 and 4.5. The denaturation extent of proteins was also determined by differential scanning calorimetry (DSC). All properties studied were dependent on pH. The WHC and consistency of gels decreased when pH decreased. These results correlated with microstructural changes observed by SEM. Spray drying affected the consistency of gels. The penetration force of the gel from dehydrated plasma was always lower than that prepared from liquid plasma where the pH was the same, but neither the WHC nor the micro-structure of gels were affected.     

亚硫酸钠对小鼠不同脏器的DNA损伤

本文对亚硫酸盐诱发小鼠不同脏器（脑、心、肺、胃、肝、脾、肾、胸腺和骨髓）细胞的DNA损伤进行了研究。运用单细胞凝胶电泳技术（又称彗星试验）对3个染毒组的小鼠腹腔注射125、250、500mg／kg bw亚硫酸钠和亚硫酸氢钠混合液（3：1，mol／L：mol／L），每天1次，共7d，并测量细胞DNA迁移长度。对照组小鼠腹腔注射生理盐水。结果表明，亚硫酸盐可引起受试小鼠多种脏器细胞DNA迁移长度显著增加，并具有明确的剂量一效应关系。这些结果提示亚硫酸盐可引起小鼠多种脏器细胞的DNA损伤，而不仅只作用于呼吸器官，是一种全身性DNA损伤因了，一种全身性毒物。     

由大蒜叶制备叶绿素亚铁钠盐及其稳定性研究

将净化处理后的大蒜叶打碎成浆,经皂化、酸化、铁代等过程,制得叶绿素亚铁钠盐。结果表明,该工艺能够减少有机溶剂的使用,所得产品水溶性好,在酸性条件下稳定性好,但是碱性条件下稳定性变差;对光的稳定性差,温度低于80℃时热稳定性较好;具有很好的耐还原能力,耐氧化性能较差;Cu2+、Fe3+和柠檬酸对叶绿素亚铁钠盐的吸光度有影响,其他添加剂对其吸光度无明显影响。     

Effects of rumen-protected choline and dry propylene glycol on feed intake and blood parameters for Holstein dairy cows in early lactation

A 6 × 6 Latin square design was used to test 3 sets of comparisons simultaneously to study response in dry matter intake, milk yield, and blood parameters to propylene glycol (PG) supplementation delivered by 2 methods [incorporating PG into the total mixed ration (TMR) vs. top dressing; comparison I]; individual or combined dietary choline and PG supplementation as a 2 × 2 factorial (comparison II); or increasing amounts of dietary choline (comparison III). Six multiparous (lactation number = 1.5 ± 0.8 SD) Holstein dairy cows were at 41 d in milk (± 9 SD) at the start of the experiment. Propylene glycol used was a dry product containing 65% PG, and choline was a rumen-protected choline product (RPC; estimated to be 50% rumen-protected) containing 50% choline chloride. In comparison I, treatments compared were 1) control: no PG; 2) PG-TMR: 250 g/d of dry PG (corresponding to 162.5 g/d of PG) incorporated into the TMR; and 3) PG-top dress: 250 g/d of dry PG top-dressed onto the TMR. In comparison II, treatments compared were 1) control: no PG and no RPC; 2) PG: 250 g/d of dry PG incorporated into the TMR; 3) RPC: 50 g/d of RPC top-dressed onto the TMR; and 4) PG + RPC: combination of treatments 2 and 3. In comparison III, treatments compared were 0, 25, and 50 g/d of RPC top-dressed onto the TMR. Each experimental period lasted 10 d with 9 d of adaptation followed by 1 d of serial blood sampling. Dry matter intake and milk yield were recorded daily. During the serial blood sampling, jugular blood was sampled every 20 min for the first 4 h and at 8 and 12 h after treatment administration. Results obtained from comparison I showed that feeding 250 g/d of PG as a dry product decreased plasma β-hydroxybutyrate (BHBA) concentration (mean ± SEM) from 701 ± 81 (control) to 564 ± 76 μmol/L without affecting serum insulin, plasma glucose, or plasma nonesterified fatty acid concentrations. Top-dressing PG decreased plasma BHBA concentrations more than by incorporating it into the TMR [527 vs. 601 μmol/L (± 81 pooled SEM)]. Results obtained from comparison II showed that supplementing choline as RPC, PG, or both had no effect on dry matter intake, milk yield, or any of the blood parameters measured. Results obtained from comparison III showed that milk yield tended to increase linearly with increasing amounts of dietary choline as RPC. We concluded that feeding PG as a dry product reduced plasma BHBA concentration but top-dressing PG was more efficient at reducing plasma BHBA level than incorporating PG into the TMR. Dietary choline as RPC tended to increase milk yield linearly. However, a combined effect of dietary PG and choline was not evident and therefore not beneficial.     

硫酸亚铁和富马酸亚铁对母猪及仔猪血液指标的影响研究

将母猪随机分为两个组,分别饲喂添加来源于硫酸亚铁和富马酸亚铁的铁元素150 mg/kg的母猪基础日粮.各组的每窝仔猪出生后选取一半注射牲血素1 ml,另一半则不注射.结果表明:(1)富马酸亚铁组对母猪血液指标的影响较硫酸亚铁组差异不显著.(2)同一组中,注射牲血素的仔猪血液指标均极显著高于未注射牲血素的仔猪.(3)在注射牲血素的情况下,富马酸亚铁组的仔猪各血液指标(红细胞压积除外)均显著高于硫酸亚铁组;在未注射牲血素的情况下,富马酸亚铁组的仔猪各血液指标均极显著高于硫酸亚铁组.     

富铁锌苜蓿芽对小鼠血液和脏器铁锌积累的研究

研究富铁锌苜蓿芽对小鼠生长发育,毒性及血液和脏器铁锌含量及吸收率。通过用试验培育出的苜蓿芽和用无机盐硫酸亚铁和硫酸锌作为对照饲喂昆明种小白鼠,考察各个剂量组对小鼠生长发育,死亡率及铁锌富集规律的影响。结果表明:苜蓿芽组比无机盐组更能促进小鼠的生长发育,随剂量的增加,小白鼠生长逐渐减慢。苜蓿芽组比无机盐组对小鼠毒害作用小,铁和锌元素吸收率高,但随着剂量的增加,吸收率降低。     

酒度、总酸、pH值以及饮用温度对干红葡萄酒涩味的影响

利用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（sodium dodecyl sulphate polyacrylamide gel electrophoresis,SDS-PAGE）分析唾液蛋白与模拟酒反应后蛋白减少比例,并将其表示为涩味强度;同时,以酒度、总酸、pH值以及饮用温度为考察因素,利用二次正交旋转组合设计分析各因子对涩味强度的影响。结果表明：pH值对涩度影响最大,其次是酸度和温度,酒度影响最小;其中pH值和酸度互作效应对涩味的影响显著。     

银杏叶提取液复合涂膜对鲜切苹果品质的影响

以‘红富士’苹果为试材,采用0.5 mg/mL银杏叶提取液及其与1%海藻酸钠复合涂膜两种方式处理鲜切苹果,从色泽、硬度、质量损失率、VC含量、多酚氧化酶活性、菌落总数以及感官评定等方面对鲜切苹果的保鲜效果进行评价,探讨银杏叶提取液及其复合涂膜对鲜切‘红富士’苹果保鲜的影响。结果表明：银杏叶提取液处理和银杏叶提取液复合海藻酸钠涂膜处理均可降低鲜切‘红富士’苹果贮藏期间的呼吸强度及乙烯释放速率,延缓鲜切苹果可溶性固形物、可滴定酸和VC含量的下降,减缓鲜切苹果的质量损失及硬度的下降,抑制贮藏期间苹果表面微生物的生长,使多酚氧化酶和过氧化物酶的活性维持在较低的水平,较好地维持了鲜切苹果的感官品质,银杏叶提取液复合海藻酸钠涂膜保鲜效果最佳。     

南瓜中降血糖活性成分的提取及其功能性质的研究

为探寻南瓜中对正常及糖尿病模型小鼠血糖有影响的有效成分 ,本实验采用新的分离工艺从南瓜粉中提取得到南瓜粗多糖 (PP) ,用DEAE分级获得 3个组分 ,收集的主导组分经过SephadexG 10 0柱分级 ,以小白鼠血糖值作为筛选活性成分的指标 ,收集有活性的组分(PP CG)经SephadexG 2 0 0证实为单一峰。气相色谱分析其单糖组成为葡萄糖、半乳糖、阿拉伯糖及鼠李糖。高效液相色谱证明其为杂多糖 ,分子质量为 1.16× 10 5u。     

米糠提取物二十八烷醇对断奶仔猪生产性能和血液指标的影响

将米糠提取物二十八烷醇应用于断奶仔猪教槽料中,探索二十八烷醇对断奶仔猪生产性能和血液指标的影响,并与抗生素泰妙菌素效果进行比较,旨在探索二十八烷醇替代抗生素的可能性。选取105头21日龄、初始体重为(5.70±1.41)kg的健康"杜×长×大"断奶仔猪,随机分为3组,即对照组、泰妙菌素组和二十八烷醇组,每组7个重复,每个重复5头猪,进行饲养试验,试验期42 d,分别测定各组仔猪的生长性能、日粮中养分消化率、腹泻程度和血液指标。结果表明,整个试验期内,与对照组相比,二十八烷醇组仔猪的日增重、饲料转化率、腹泻程度和血液指标均显著优于对照组(P0.05),并可提高日粮中干物质和粗蛋白质的表观消化率;与泰妙菌素组相比,二十八烷醇组仔猪的血液指标与泰妙菌素组存在显著性差异(P0.05),日增重、饲料转化率、营养成分消化率和腹泻程度指标与泰妙菌素组效果无显著差异(P0.05)。因此,二十八烷醇可替代抗生素用于断奶仔猪教槽料中,为开发安全、高效、无残留的畜禽促生长饲料添加剂提供参考。     

纳米甘薯渣纤维素对糖尿病大鼠血糖及血脂水平的影响

目的：探讨纳米甘薯渣纤维素对糖尿病大鼠血糖及血脂的影响。方法：选用40 只雄性Sprague-Dawley（SD）大鼠随机分组为5 组,其中1 组大鼠喂食基础饲料作为空白组,另外4 组采用链脲佐菌素（streptozotocin,STZ）诱导大鼠建立糖尿病模型,分为模型对照组（MC组）、普通甘薯渣纤维素组（OC组）、微晶甘薯渣纤维素组（MCC组）和纳米甘薯渣纤维素组（CNC组）,实验期28 d,测定大鼠体质量、采食量、空腹血糖、糖化血清蛋白、血清胰岛素、肝糖原及血脂水平等指标。结果：模型对照组大鼠的采食量,空腹血糖、糖化血清蛋白、血脂水平均显著高于空白组（P＜0.05）,体质量、胰岛素和肝糖原含量明显下降（P＜0.05）,说明造模成功,糖尿病大鼠表现出相应的症状。喂食不同粒度甘薯渣纤维素的糖尿病大鼠,其体质量、血清胰岛素和肝糖原水平有所增加,而空腹血糖、糖化血清蛋白、血脂水平等都有所下降,其中喂食纳米甘薯纤维素的糖尿病大鼠指标变化具有显著性差异（P＜0.05）。结论：从甘薯渣纤维素粒度分析,可以看出随着甘薯渣纤维素粒度的减小,其对糖尿病大鼠血糖血脂的调节作用愈加明显,其中纳米甘薯渣纤维素具有较好的调节血糖血脂水平的作用。     

Assessing Potential Effects of Inulin and Probiotic Bacteria on Fe Availability from Common Beans (Phaseolus vulgaris L.) to Caco-2 Cells

ABSTRACT:  Inulin, a prebiotic, may enhance intestinal Fe absorption. Our objective was to assess the effects of supplemental inulin and 2 probiotic bacteria ( B. infantis and L. acidophillus ) on Fe availability to Caco-2 cells from common white and red beans ( Phaseolus vulgaris L.). Cooked beans were mixed or not with supplemental inulin (4%, w/w), and then subjected to simulated gastrointestinal digestion (pepsin, pH 2; pancreatin, pH 7.2). Subsequently, the digests were incubated overnight with and without B. infantis or L. acidophilus . Ferritin formation in Caco-2 cells was used to evaluate Fe uptake. Total soluble phenols (Folin–Ciocalteau) and phytate (HPLC-electrochemical detection) were quantified, and the flavonoids profile (HPLC-PDA/UV detection) was monitored in the digests. Supplemental inulin did not affect Fe uptake from white nor red beans. Incubation with B. infantis increased total soluble phenols (TSP) in the digests and decreased Fe uptake. Incubation with L. acidophilus decreased TSP in the digest and increased Fe uptake. Variations in Fe uptake were not associated with soluble phytate concentrations in the digests. The largest change in flavonoids profile were found in the digests incubated with L. acidophilus , which decreased the soluble concentration of astragalin (kaempferol-3-O-glucoside). These results suggest that certain probiotics could increase Fe uptake from common beans.