桑葚复合酸奶的研制

将桑葚果汁与脱脂牛乳复配,经过酸乳发酵工艺可制备出口感良好、营养丰富并具有多种功能的保健酸奶。经研究,桑葚酸奶的最佳配方为白砂糖添加量4%、桑葚汁含量6%、发酵剂接种量6%、发酵时间6 h。在最佳条件下制得的酸奶感官评分为85.3分,品质、风味、口感俱佳。     

低脂无糖保健酸奶的研制

在酸奶配方的基础上,利用低聚果糖和木糖醇配比以取代全部的蔗糖,利用脱脂乳粉部分取代全脂乳粉,采用多因素正交试验设计出低脂无糖保健酸奶的最佳配方。结果表明：采用低聚果糖和木糖醇配比为1.5%和4.0%,脱脂乳粉和全脂乳粉配比为4.5%和4.0%,低脂无糖保健酸奶的感官品质最佳。     

胶原蛋白酸奶的研制

以新鲜牛乳为原料,添加天然深海鳕鱼皮提取的胶原蛋白,经杀菌、真空浓缩、冷却、添加乳酸菌发酵剂发酵,开发了具有营养和保健功效的胶原蛋白酸奶,其主要成分为:蛋白质4％(其中胶原蛋白≥1％),脂肪3.5％,碳水化合物11％,固形物21.8％(均为质量分数),乳酸菌数9×108 g-1.该生产工艺可行、技术上合理、设备上可操作...     

酶解糯米制作酸奶工艺的优化

以糯米酶解液、奶粉为原料进行乳酸发酵,制得一种新型凝固酸奶——糯米酸奶。通过单因素试验初步确定加工工艺参数,再用正交试验得出制作糯米酸奶的最佳工艺条件。试验结果表明最佳工艺条件为：糯米酶解液与奶粉液体积比72∶28、白砂糖2.8%、发酵剂3%,在42℃发酵4h。在此最佳条件下获得的酸奶产品品质最好,兼具糯米和酸奶的风味特点。     

新型无糖苦瓜酸奶的研制

研究了具有营养保健功能的无糖苦瓜酸奶的加工工艺,结果表明:以鲜苦瓜为原料,用100mg/kg葡萄糖酸锌作为护色剂、1%-β环状糊精作为苦味包埋剂,可制得质量良好的苦瓜汁;采用苦瓜汁∶鲜牛奶=37∶的原料配比、阿斯巴甜0.05%、复合稳定剂0.15%,将保加利亚乳杆菌和嗜热链球菌以11∶混合作为发酵剂进行发酵、接种量3%、发酵温度42℃、发酵时间5h等工艺条件,可得到品质风味优良的新型无糖苦瓜酸奶。     

Novel probiotic-fermented milk with angiotensin I-converting enzyme inhibitory peptides produced by Bifidobacterium bifidum MF 20/5

In previous research, we have demonstrated that Bifidobacterium bifidum MF 20/5 fermented milk possessed stronger angiotensin converting enzyme (ACE) inhibitory activity than other lactic acid bacteria, including Lactobacillus helveticus DSM 13137, which produces the hypotensive casokinins Ile-Pro-Pro (IPP) and Val-Pro-Pro (VPP). The aim of this study is to investigate the ACE-inhibitory peptides released in B. bifidum MF 20/5 fermented milk. The novel ACE-inhibitory peptide LVYPFP (IC₅₀ = 132 μM) is reported here for the first time. Additionally, other bioactive peptides such as the ACE-inhibitor LPLP (IC₅₀ = 703 μM), and the antioxidant VLPVPQK were identified. Moreover, the peptide and amino acid profiles, the ACE-inhibitory activity (ACEi), pH, and degree of hydrolysis of the fermented milk were determined and compared with those obtained in milk fermented by L. helveticus DSM 13137. The sequences of the major bioactive peptides present in fermented milk of B. bifidum and L. helveticus were identified and quantified. B. bifidum released a larger amount of peptides than L. helveticus but no IPP or VPP were detected in B. bifidum fermented milk. Also the lactotripeptide concentrations and ACEi were higher in L. helveticus fermented milk when the pH was maintained at 4.6. This may represent a technical advantage for B. bifidum that reduces the pH at a slow enough rate to facilitate the peptide generation without the need for pH control. Thus these findings show the potential for the use of this probiotic strain to produce fermented milk with a wider range of health benefits including reduction of blood pressure.     

Effect of papain‐hydrolysed casein peptides on the fermentation kinetics,microbiological survival and physicochemical properties of yoghurt

The objective of this study was to determine the effect of different molecular mass papain‐hydrolysed casein peptides (PCP) on the growth of lactic acid bacteria (LAB) (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus in 1:1 ratio) and on the fermentation kinetics, microbiological survival and physicochemical properties in yoghurt. The fraction of PCP4 (<3 kDa) exhibited the highest growth‐promoting activity on the strains. The value of T_pH4.5 (time necessary to reach pH 4.5) of yoghurt fortified with PCP4 reduced from 5.21 to 4.29 h, and the total counts of LAB present in the final products increased from 8.29 to 8.42 log CFU mL^?1 with the addition of PCP4 at nitrogen replaced ratio of 3% (w/w). Moreover, the yoghurt exhibited lower postacidification power, higher viscosity and sensory evaluation scores than did the control product during storage period.     

低聚异麦芽糖改善小鼠胃肠道功能的研究

以二月龄雄性BALB／c小鼠为实验对象,研究了IMO－50与IMO－90调节胃肠道菌群的功能,结果表明：连续给予IMO－50或IMO－9014天后,小鼠胃肠疲乏内双歧杆菌数量显著增加。以二月龄雄性BALB／c小鼠为实验对象,以复方地芬诺酯建立的便秘模型为参比对照,研究IMO-50IMO－90的润畅通便功能,结果表明：在连续给予受试物14天后,便秘小鼠的肠推进率显著提高,首便、首黑便时间明显缩短,8小时排便重量显著增加。提示IMO－50和IMO－90均可改善小鼠胃肠道功能。     

果蔬绿豆发酵酸乳的研制

本饮品是利用绿豆和牛乳为发酵原料，保加利亚乳杆菌、嗜热链球菌和啤酒酵母为发酵菌剂酿制成发酵酸乳后，再配以山渣、胡箩卜、枸杞浆调制而成的。其中含有原料的全部可食部分，营养价值高。     

三聚氰胺对酸乳发酵的影响

为了阐明三聚氰胺对酸乳发酵的影响,以含不同浓度三聚氰胺的鲜牛乳为原料进行了酸乳的发酵实验,测定了发酵过程中的pH值、发酵前后的活菌数及凝乳时间.结果表明：添加三聚氰胺会增大凝乳时的pH值,变化的最大值为0.78;也会增加凝乳时间,增加的最大值为1.5 h;凝乳时,乳酸菌的活菌数有所下降,但下降值不超过一个数量级;酸乳中三聚氰胺浓度越高,凝乳时质地越疏松;酸乳中菌体的形态差异并不明显.