亲水性胶体在乳制品工业中的应用

<正> 亲水性胶体是指水溶性多糖,其作用是使多糖分散体系具有黏度和形成凝胶的能力。根据原料来源,亲水性胶体可分为:生物胶(黄原胶、葡聚糖、结冷胶)、植物胶(刺槐豆胶、瓜尔豆胶)、植物渗出液(阿拉伯胶、黄耆胶)、海藻胶(卡拉胶、琼胶)、纤维素及衍生物(纤维素、羧甲基纤维素(钠))、淀粉及其衍生物、动物胶(明胶)、果胶。 在乳制品工业中被广泛应用的亲水性胶体主要有刺槐豆胶、瓜尔豆胶、果胶和卡拉胶。主要作用是保护体系中的蛋白质以耐受加工中     

美拉德反应提高鸡蛋白粉凝胶性质的研究

采用果胶酶水解果胶、盐酸水解魔芋胶和瓜尔豆胶的方式得到了三种胶的水解产物,并将其与脱糖鸡蛋白粉进行美拉德反应以改进蛋白质的凝胶性质。通过对胶的水解条件、产物的凝胶性质、色泽、消化性等性质的研究,发现瓜尔豆胶经盐酸在80℃水解3h后,其还原基团数为7.3mmol/g瓜尔豆胶,将该水解物与蛋白粉以1∶100的比例在控制条件下进行美拉德反应,所得蛋白粉-瓜尔豆胶复合物的凝胶强度达1378.9g,比普通蛋白粉提高1207%,复合物色泽、消化性、溶解性均可接受,且优于蛋白粉与果胶或魔芋胶的反应产物。     

芝麻风味复合蛋白饮料稳定性研究

芝麻风味复合蛋白饮料是新兴的健康饮品,其稳定性和良好的风味体现是产品成功的关键。本文为了研制风味接受度较高,体系较稳定的芝麻风味复合蛋白饮料,探讨了不同稳定剂对体系稳定性的影响。通过单因素实验、正交试验,对芝麻风味复合蛋白饮料的产品稳定性进行了研究。实验以4.8%全脂奶粉加0.65%大豆分离蛋白,配合添加0.1%芝麻主剂。以蔗糖、阿斯巴甜、安塞蜜作为复合甜味物质。以瓜尔豆胶、k—卡拉胶、微晶纤维素(MCC)和蔗糖酯为复合稳定体系。以乳香精和芝麻香精(比例1∶2)总量0.06%为调香方案。均质温度65~70℃,压力25MPa,杀菌温度121℃,10min,研制出稳定性较高、风味体现较好的芝麻风味复合蛋白饮料。结果显示:在稳定性上,瓜尔豆胶、k—卡拉胶、MCC配合使用对产品的稳定性有较好的影响,通过正交试验优选出稳定剂瓜尔豆胶、k—卡拉胶、MCC最佳配合为:0.03%、0.03%、0.15%,影响度大小顺序为MCk—卡拉胶瓜尔豆胶。     

膳食纤维抑制膳后血糖升高的机理探讨

采用麦麸水不溶性膳食纤维，难消化糊精，麦麸水溶性膳食纤维，羧甲基纤维素，瓜尔豆胶和黄原胶进行了模拟试验，探讨了膳食纤维抑制膳后血糖升高的作用机理，结果表明，膳食纤维至少通过以下三种方式减缓小肠对葡萄糖的吸收，抑制膳后血糖升高，一增加肠液粘度，阻碍葡萄糖的扩散；二束缚葡萄糖，降低肠液中葡萄糖的有效浓度，三影响α－淀粉酶对淀粉的降解作用，延长酶解时间，降低肠液中葡萄糖的释放速率。     

复合纤维素溶胶中营养物质传递特性浅探

以质量分数为2:3的大豆非水溶性纤维素(soybeaninsolublefiber,SIF)和瓜尔豆胶(guar)配制固形物含量为5g/200ml的复合纤维素溶胶,采用SEM(scanningelectronmicroscopy)进行了显微观察、分析,模拟人体中营养物质的吸收条件,进行了体外营养物质传递实验,测定了复合纤维素溶胶中葡萄糖、VC、K+的传递特性后发现,在试验浓度下的复合溶胶体系中,葡萄糖的传质速率仅为在单组分的SIF悬液及guar溶胶中的50%以下;复合溶胶对VC的滞留能力较弱,而对K+的滞留能力较强。     

稳定剂对乳体系稳定性影响的研究

通过稳定剂的单因素实验和复配试验,对乳体系的稳定性进行了研究。采用离心沉淀率、粘度及粒度相结合的方法,研究了不同稳定剂对乳体系稳定性的影响。实验结果表明：5种稳定剂中,PGA对乳体系的稳定效果最好,且最佳添加量为0.10%,PGA分别与瓜尔豆胶、黄原胶或果胶复配,都有协同增效作用,且PGA与黄原胶在添加量3∶7时对乳体系的稳定效果最好。     

亲水胶体对胡柚饮料稳定性的影响

以胡柚饮料为研究对象,以离心沉淀率和混浊稳定性为考察指标,探讨了添加黄原胶、羧甲基纤维素（CMC）、瓜尔豆胶和果胶4种亲水胶体对胡柚饮料稳定性的影响。结果表明：随着亲水胶体添加量的增加,胡柚饮料的稳定性呈上升趋势,其适宜的添加量为0.15%～0.2%,亲水胶体的稳定性顺序为：果胶〉CMC〉瓜尔豆胶〉黄原胶;黄原胶与果胶复配比为1∶2～3,添加量为0.15%～0.2%时,胡柚饮料稳定性最好,口感最佳。     

不同品种膳食纤维影响小鼠糖耐量结果的比较

本文选择多功能大豆纤维（MSF）、小麦纤维、纤维素、果胶和瓜儿胶等5种膳食纤维，对其影响小鼠葡萄糖耐量结果作了比较与分析。结果显示，1.0g/kg MSF、果胶或瓜儿胶可使葡萄糖耐量曲线变得尤为平缓，而同剂量纤维素和小麦纤维的效果并不显著。水溶性、粘性膳食纤维具有明显的稳定餐后血糖的作用，原因可能在于它能增加小肠内容物粘性，增加肠内非搅动层（unstirred layer）的厚度，并能使胃的排空速率降低，从而显著降低葡萄糖吸收速度。     

复配食品胶的研究进展

复配食品胶是指根据各种单体胶的性能，将两种或两种以上的单体胶按照一定的比例复配而成的复合物，具有增稠、稳定、悬浮、胶凝、乳化、组织改进等作用。典型的食品胶有变性淀粉、黄原胶、果胶、海藻酸钠、明胶、琼脂、卡拉胶、瓜尔豆胶、魔芋胶等几十种。     

调配型酸乳饮料中最优稳定剂的选择

在制作酸性乳饮料时需添加稳定剂。探讨了稳定剂与酪蛋白的作用机理。选用果胶、CMC、PGA、瓜尔豆胶、黄原胶5种稳定剂,通过离心沉淀率的测定,选取其中稳定效果最优的稳定剂。结果表明：在酸乳饮料体系中,果胶是最优稳定剂。     

Utilizing whey protein isolate and polysaccharide complexes to stabilize aerated dairy gels

Heated soluble complexes of whey protein isolate (WPI) with polysaccharides may be used to modify the properties of aerated dairy gels, which could be formulated into novel-textured high-protein desserts. The objective of this study was to determine the effect of polysaccharide charge density and concentration within a WPI-polysaccharide complex on the physical properties of aerated gels. Three polysaccharides having different degrees of charge density were chosen: low-methoxyl pectin, high-methoxyl type D pectin, and guar gum. Heated complexes were prepared by heating the mixed dispersions (8% protein, 0 to 1% polysaccharide) at pH 7. To form aerated gels, 2% glucono-δ-lactone was added to the dispersions of skim milk powder and heated complex and foam was generated by whipping with a handheld frother. The foam set into a gel as the glucono-δ-lactone acidified to a final pH of 4.5. The aerated gels were evaluated for overrun, drainage, gel strength, and viscoelastic properties. Without heated complexes, stable aerated gels could not be formed. Overrun of aerated gel decreased (up to 73%) as polysaccharide concentration increased from 0.105 to 0.315% due to increased viscosity, which limited air incorporation. A negative relationship was found between percent drainage and dispersion viscosity. However, plotting of drainage against dispersion viscosity separated by polysaccharide type revealed that drainage decreased most in samples with high-charge-density, low-methoxyl pectin followed by those with low-charge-density, high-methoxyl type D pectin. Aerated gels with guar gum (no charge) did not show improvement to stability. Rheological results showed no significant difference in gelation time among samples; therefore, stronger interactions between WPI and high-charge-density polysaccharide were likely responsible for increased stability. Stable dairy aerated gels can be created from WPI-polysaccharide complexes. High-charge-density polysaccharides, at concentrations that provide adequate viscosity, are needed to achieve stability while also maintaining dispersion overrun capabilities.     

食品增稠剂瓜儿豆胶性质及复配性的研究

本文对瓜尔豆胶的流变性,浓度、温度、pH值、电介质对粘度的影响,与黄原胶、卡拉胶复后粘度变化进行了初步研究。结果表明,低浓度瓜儿豆胶属非牛顿流体中假塑性流体,其粘度随浓度升高而上升,随温度升高而下降,几乎不受pH值影响,对NaCl和低浓度Ca~(2+),Al~(3+)有良好兼容性,与卡拉胶复配无增效作用,而与黄原胶复配增效显著,复配最佳比例为瓜儿豆胶:黄原胶=0.6:0.4     

瓜尔豆胶对锥栗淀粉糊化和流变学特性的影响

以新鲜锥栗为原料,考察了瓜尔豆胶对锥栗淀粉的糊化特性和流变学特性的影响。结果表明,向锥栗淀粉中添加瓜尔豆胶后,锥栗淀粉糊化溶液的峰值黏度和终值黏度增大,且随瓜尔豆胶添加比例的增加而增大;添加瓜尔豆胶增大了锥栗淀粉的起始糊化温度和峰值糊化温度,提高了锥栗淀粉的吸热焓,使得糊化过程更长,吸热更多。添加瓜尔豆胶后的锥栗淀粉溶液显示为假塑性流体,剪切变稀现象更为明显,具有更大的黏弹性。添加瓜尔豆胶后,混合物形成的凝胶表面空隙中填充物增多,空隙数量减少,且空隙分布更加均匀。     

Development and characterization of soluble fiber enriched noodles via fortification with partially hydrolyzed guar gum

Partially hydrolyzed guar gum was prepared via enzymatic hydrolysis of native guar gum. Partially hydrolyzed guar gum (PHGG) thus obtained after enzymatic hydrolysis contained 80.04% soluble dietary fiber and 83.1% total dietary fiber. In present study, the effect of process variables such as PHGG level (1–5%), water level (30–40%) and mixing time (2–6 min) on response variables i.e. cooking yield, cooking loss and overall acceptability of noodles were studied using response surface methodology. The second order model obtained for cooking yield, cooking loss and overall acceptability of noodles revealed coefficient of determination of 0.9796, 0.9446 and 0.7787, respectively. The optimum values for independent variables i.e. PHGG level, water level and mixing time were 2.23, 32.03% and 2.81 min, respectively. Results showed that noodles with reduced cooking yield, increased cooking loss and improved sensory and textural characteristics were prepared with fortification of 2.23% partially hydrolyzed guar gum as soluble fibre.     

低黏度瓜尔胶的制备及其增强性能研究

以双氧水为氧化剂,对羟丙基瓜尔胶进行氧化降解,使其黏度从2390mPa·s降到10mPa·s以下。将降解后的瓜尔胶对滤嘴棒纸进行涂布,研究其增强性能,考察其对纸张抗张指数、裂断长、撕裂度、耐破度和耐折度的影响。得出低黏度瓜尔胶氧化降解的较佳工艺为:密封,过氧化氢用量为8.6%、反应温度65℃、反应时间4h。选出效果较优的低黏度羟丙基瓜尔胶,研究涂布浓度和涂布温度对其增强性能的影响。最后将制备的低黏度瓜尔胶与改性淀粉对滤嘴棒纸的增强性能做了比较。     

瓜尔豆胶对搅打稀奶油的搅打性能的影响

研究了不同浓度的瓜尔豆胶对搅打稀奶油乳状液的表观黏度、脂肪球粒度、脂肪球界面蛋白浓度、脂肪球部分聚结率、泡沫硬度和搅打起泡率的影响。结果表明，瓜尔豆胶对搅打稀奶油乳状液的表观黏度影响非常显著；瓜尔豆胶浓度过高或过低，都会使得解冻后的乳状液粒径变大；瓜尔豆胶的质量分数越高，脂肪球部分聚结速度越快，泡沫硬度也越大；搅打起泡率随着瓜尔豆胶质量分数增大而降低。     

亲水多糖对鲜湿面货架期内水分迁移及老化进程的影响

利用低场核磁共振、差示量热扫描、Avrami数学模型研究瓜尔胶、可溶性大豆多糖、卡拉胶对鲜湿面贮藏期间水分迁移、热力学参数、老化动力学的影响。结果表明：贮藏7 d的鲜湿面结合水含量：瓜尔胶＞可溶性大豆多糖＞卡拉胶＞空白组（P＜0.05）;不易流动水含量：瓜尔胶＞卡拉胶＞可溶性大豆多糖＞空白组（P＜0.05）;自由水含量：空白组＞可溶性大豆多糖＞卡拉胶＞瓜尔胶（P＜0.05）。多糖主要作用于淀粉及面筋蛋白表面极性基团所吸引的结合水;同时多糖对3 种水分流动性的束缚并非呈单一的线性关系,且能抑制鲜湿面淀粉老化过程中重结晶融化起始温度（T0）、重结晶融化终止温度（Tc）、老化焓（?H）的上升速率;老化动力学方程：Y空白组=0.732x－0.946,Y卡拉胶=0.744x－1.192,Y瓜尔胶=0.791x－1.328,Y可溶性大豆多糖=0.752x－1.114。     

不同条件对胖大海胶表观黏度的影响

以胖大海胶研究对象,研究pH、钙离子浓度、不同阳离子、蔗糖及其他胶体对胖大海胶黏度的影响。结果表明:pH偏高或偏低、阳离子存在均使胶体溶液表观黏度下降;随着蔗糖浓度增加,溶液表观黏度逐渐增大;胖大海胶与瓜尔豆胶复合后胶体溶液黏度大于原胶体的黏度,而与黄原胶、海藻酸钠、琼脂复合则小于原胶体黏度。     

瓜尔胶用于浆内增强及助留助滤

实验研究了瓜尔胶在浆内增强作用及助留助滤作用，对瓜尔胶和阳离子淀粉混合使用做了对比。结果表明，加入瓜尔胶后能提高强度、留着率，改善滤水效果。瓜尔胶与阳离子淀粉混合使用，增强、助留助滤作用更明显。