产L－乳酸的菌种的筛选及L－乳酸生产新途径

本实验以大豆秸秆酶解液为原料,发酵制备L- 乳酸。首先对产L- 乳酸的四株菌进行筛选,选出性能优良、糖利用率和乳酸产量均较高的干酪乳杆菌作为实验用菌种。然后对乳酸菌发酵大豆秸秆酶解液制备L- 乳酸的影响因素进行了研究,研究结果表明：干酪乳杆菌发酵的最佳接种量为10%,最适发酵温度为30℃,最佳pH 值为5.5;在发酵42h 时,大豆秸秆酶解液中残留糖浓度接近于零,此时,随底物浓度的增高,乳酸产量相应增加,并且酶解液浓度达到34.98g/L 时,乳酸生产没有受到抑制。     

由大豆秸秆酶解液制备L-乳酸试验研究

以大豆秸秆酶解液为原料，对乳酸发酵菌株进行了筛选，并研究了利用乳酸菌发酵生产食品工业中的安全添加剂L-乳酸的发酵条件。结果表明，混合菌种发酵优于单一菌种发酵，以葡萄糖计，糖酸转化率为71．05％。     

酸豆奶生产技术

近年来研究表明,采用优质大豆提取豆奶,并用现代生物工程乳酸发酵技术可制造出风味独特的酸豆奶。本文着重论述大豆经干脱皮、清洗灭酶、磨浆、浆渣分离、脱腥、超滤、标准化、巴氏杀菌以及加入乳酸菌进行乳酸发酵等工艺过程,并对在制造过程中有关大豆抗营养因子的去除,ｐＨ 的掌握进行了讨论     

乳酸菌发酵植物蛋白质饮料的研究

乳酸菌发酵植物蛋白饮料是以大豆为主要原料，通过一系列科学加工除掉大豆的腥味和对人体不利因素，再经乳酸发酵研制而成的有益于人体健康的营养型饮料。     

乳酸菌发酵大豆糖蜜生产乳酸及糖代谢变化

选用德氏乳杆菌保加利亚亚种KLDS1.8501、嗜酸乳杆菌KLDS1.0327、嗜酸乳杆菌ATCC11975、植物乳杆菌植物亚种CICC23168、干酪乳杆菌ATCC393、植物乳杆菌NAU322分别接种于大豆糖蜜,用高效液相色谱法测定乳酸的产生以及碳水化合物的利用情况,分析不同乳酸菌发酵大豆糖蜜生产乳酸能力及糖代谢能力。结果表明,在15 °Brix大豆糖蜜中,37?℃、pH?6.0条件下发酵24?h,植物乳杆菌植物亚种CICC23168的活细胞数达到6.66×109?CFU/mL,乳酸产生量为12.18?g/L,总糖消耗量为22.48?g/L,与其他菌株相比有明显优势。因此,植物乳杆菌植物亚种CICC23168是能利用大豆糖蜜发酵产乳酸的潜力菌株。     

乳酸菌发酵植物蛋白质饮料的研究

乳酸菌发酵植物蛋白饮料是以大豆为主要原料，通过一系列科学加工除掉大豆的腥味和对人体不利因素，再经乳酸发酵研制而成的有益于人体健康的营养型饮料。     

乳酸发酵豆乳饮料生产工艺

以大豆为主要原料,经磨浆、加入驯化后的乳酸菌发酵成熟后进行调配,制成乳酸发酵豆乳饮料。     

灵芝液体深层发酵豆乳饮料的研制

以大豆为原料,采用液体深层发酵技术研究灵芝发酵豆乳饮料的制备工艺.大豆经浸泡、磨浆、过滤、杀 菌后接种灵芝菌种发酵,经调配后制成富含大豆和灵芝有效成分的饮料.以灵芝多糖的含量为指标.研究大豆加水比,通过单因素和正交试验优化灵芝发酵工艺条件,结果表明最适的大豆加水比为110,最佳发酵工艺条件为接种量6%、装液量100 mL、发酵温度28℃、发酵时间6 d.发酵后对饮料进行调配,加入6%蔗糖和0.1%乳酸可明显改善产品的苦味.     

玉米,大豆混合发酵酸奶的研制

近年来,乳酸菌发酵饮料以其独特的风味、丰富的营养和良好的保健功能受到广大消费者的重视和青睐［１～４］。目前国内外开发的乳酸发酵食品种类较多,所用原料有牛奶、鸡蛋、大豆和果蔬等,而以玉米、大豆为原料研制的混合型纯天然发酵酸奶,报道甚少。以玉米、大豆和鲜牛奶为原料,经过工艺研制的凝固型混合酸奶,产品兼有玉米和乳酸菌发酵制品特有的风味、营养和保健作用,从而为玉米和大豆的深加工以及丰富乳酸发酵饮料市场具有重要的现实意义。１材料与方法１．１主要原辅料：玉米、大豆;鲜牛奶：市售;蔗糖,乳糖：食用级。１．２发…     

利用大豆秸秆酶解液发酵制备L-乳酸的动力学研究

对乳酸菌发酵大豆秸秆酶解液制备L-乳酸的动力学特性进行了研究,基于monod方程,提出了固定化乳酸菌生长动力学模型;基于gaden方程,提出了乳酸生成动力学模型,得到了描述发酵过程的动力学模型及模型参数,同时对试验数据与模型进行了验证,模型计算值与实验数据拟合良好,模型基本上反映了乳酸发酵过程的动力学特征.     

Changes of soy protein under ultra-high hydraulic pressure

High pressure (<500 MPa) was applied to soy milk and the protein changes were examined. Soy milk remained a liquid within the range of examined pressures, although its viscosity increased when the time of pressurization was less than 10 min. However, the soy milk changed from a liquid to a sol after treatment at 500 MPa for 30 min. the liquid soy milk showed improved emulsifying activity and stability but reduced emulsifying capacity. Sulfhydryl content of this soy milk was increased slightly after anaerobic pressurization. Harder tofu could be made from pressurized soy milk with CaC1₂ than could be made with unpressurized soy milk. Electrophoresis and isoelectrofocusing revealed that soy proteins were dissociated and some of them coagulated by high pressure. Fluorescence analysis also revealed that soy proteins were modified by high pressure to have larger hydrophobic regions. After pressure treatment, soy milk showed a higher affinity for beany flavour components and saponins which would lead to better use of soy milk in soy foods.     

大豆不同前处理方式对豆浆品质的影响

为探讨大豆不同前处理方式对豆浆品质的影响,选择5 种前处理方式,对所制得豆浆的感官品质、色泽、稳定性、主要营养成分及抗营养因子含量进行对比分析。结果表明：大豆不同前处理方式对豆浆品质有不同的影响。干豆直接制浆虽方便快捷,但所得豆浆品质较差,其感官品质、稳定性均差于浸泡大豆,且主要营养成分如蛋白质、多糖得率低,抗营养因子含量高;高温高压蒸煮大豆制浆,其感官品质、稳定性及抗营养因子的去除效果均差于浸泡大豆,且色泽偏暗,蛋白质损失严重,含量低于干豆制浆;与干豆直接制浆相比,浸泡处理大豆可明显改善豆浆感官品质及其稳定性,且其蛋白质、可溶性固形物、多糖含量显著提高（P＜0.05）,抗营养因子含量显著下降（P＜0.05）;免浸泡豆和NaHCO3溶液泡豆制得豆浆色泽最亮,综合品质最好。     

Fermentation and Properties of Calcium-fortified Soy Milk Yogurt

Calcium-fortified soy milk yogurt containing 190 mg calcium/100g was produced and evaluated for textural and microstructural properties. The soy milk base contained 10% full fat soy flour, 2.25% soy protein isolate, 2.75% high fructose corn syrup, 1.55% calcium lactogluconate, and 1.25% potassium citrate. The mixture was heated 5 min at 80°C, cooled to 42°C, and inoculated with yogurt cultures. Calcium-fortified soy milk required a higher rate of inoculation (5%) than non-fortified soy milk (2.5%) and had higher titratable acidity and more syneresis. Calciumfortified soy milk yogurts showed comparable gel strength with that of commercial regular yogurt. Gels from nonfortified soy milk yogurts were hard and brittle. Addition of calcium did not significantly affect microstructure of the yogurts.     

Microstructure and Texture of Process Cheese,Milk Curds,and Caseinate Curds Containing Native or Boiled Soy Proteins

Scanning electron microscopy was used to examine the internal microstructure of process cheese, process cheese containing native soy protein, process cheese containing boiled soy protein, rennet coagulated milk curd, milk curd containing native soy protein, milk curd containing boiled soy protein, rennet coagulated caseinate curd, caseinate curd containing native soy protein, and caseinate curd containing boiled soy protein. Textural characteristics were determined with an Instron Food Testing System. Soy proteins caused the fine network microstructure of processed cheese to change to coarse porous structure. Hardness of cheese was lowered, but cohesiveness was increased by adding soy protein to process cheese. In milk curd, particles of soy protein were clustered in groups in micrographs. Cohesiveness of milk curd was lowered by native soy protein and even more by boiled soy protein. Hardness and springiness were lowered by boiled soy protein. Boiled soy protein was more extensively aggregated than was native soy protein. Soy proteins were not clearly distinguishable from casein in the micrograph of caseinate curds. Soy proteins reduced hardness and cohesiveness of caseinate curd but not as drastically as in milk curd.     

大豆品种对双蛋白干酪得率和品质特性的影响

用8种不同品种大豆制作的豆乳与牛奶混合,按照切达干酪生产工艺制作双蛋白切达干酪,以同批次纯牛奶制作的干酪为对照组,对产品的得率、色泽、质构和感官特性等指标进行了分析和比较。实验结果表明,各组双蛋白干酪均比纯牛奶干酪的得率高,各组双蛋白干酪之间得率存在较大差异。质构测定结果表明,不同大豆品种生产的双蛋白干酪在硬度、弹性和粘聚性等指标方面具有较大差异。感官评价中,除添加小粒豆8号豆乳的双蛋白干酪带有较浓豆腥味外,其余组与对照组相差不大。相关性分析结果表明,大豆蛋白中球蛋白和β-伴球蛋白的比值(11S/7S)与双蛋白干酪的硬度和粘聚性显著相关,而大豆的蛋白含量、脂肪含量和植酸含量等指标与双蛋白干酪的品质指标无显著相关性。     

大豆及其有效成分体外抗蛋白非酶糖化作用

为探讨豆浆的抗蛋白非酶糖化作用及其有效成分,将20g/L的牛血清白蛋白(BSA)与80mmol/LD-葡萄糖体外孵育,与此同时分别加入不同浓度豆浆、大豆异黄酮和染料木素,糖化系统建立90d时,测定各反应体系荧光值。结果表明,100mg/ml豆浆和0.1mg/ml大豆异黄酮体外能明显抑制非酶糖化反应,且随浓度升高,抑制作用明显增强;与等浓度豆浆比较,大豆异黄酮抑制作用明显较强。1μg/ml染料木素能明显抑制牛血清蛋白的非酶糖化作用,且与阳性对照氨基胍无明显差异。该研究表明豆浆具有抗蛋白非酶糖化作用,其中的有效成分可能与大豆异黄酮有关,大豆异黄酮中的有效成分与染料木素有关。     

Effects of Enzyme Modified Soy Protein on Rennet-Induced Reconstituted Nonfat Dry Milk Coagulum Properties

Soy protein was hydrolyzed by trypsin, pepsin and α-chymotrypsin. Effects of adding hydrolyzed soy protein on rennet-induced nonfat milk coagulum texture and syneresis were studied. Pepsin-modified soy protein increased coagulum firmness and syneresis greater than untreated soy protein. Soy protein hydrolyzed with trypsin for 150 min and added to nonfat milk increased coagulum firmness greater than nonfat milk with no soy protein added. Chymotrypsin-modified soy protein acted similarly to the trypsin modified soy protein except the coagulum firmness was less than nonfat milk alone. Soy protein hydrolyzed by trypsin followed by pepsin increased coagulum firmness more than hydrolysis by a single enzyme and was close to nonfat milk without soy protein.     

Utilization of soy yoghurt in tarhana production

Tarhana, a traditional fermented food made from a mixture of white wheat flour and yoghurt, is widely consumed in Turkey. Tarhana samples with cow's milk yoghurt, soy milk yoghurt, and a blend of cow's and soy milk yoghurt were produced and evaluated for pH, viscosity, color, and sensory properties. Acid production was slower in soy milk-added samples, and increasing yoghurt amount in tarhana significantly contributed to acidity of the samples (P<0.05). Soy milk-added samples had higher viscosity compared with cow's milk yoghurt-added samples (P<0.05). Soy milk yoghurt bleached the wheat flour and therefore these samples appeared whiter than the cow's milk yoghurt-added samples (P<0.05). Panelists could not detect any beany-off flavor in soy milk yoghurt-added samples and gave similar scores to soy milk yoghurt-added tarhanas for all sensory properties     

不同预处理方法对豆浆中抗营养因子的影响

豆类中除营养成分外也含有多种抗营养因子,制作豆浆时不同预处理方法可能影响到豆浆中抗营养因子的残留量。本文就浸泡、萌发和去皮3种不同预处理方法对豆浆中胰蛋白酶抑制剂、植酸、单宁等抗营养成分的影响进行综述。与干豆制浆相比,浸泡和萌发处理均可降低所制豆浆中抗营养因子的含量,其中萌发大豆处理去除抗营养因子的效果最佳。     

Calcium Fortification of Soy Milk with Calcium-Lecithin Liposome System

Calcium ion was enveloped with a membrane system before addition to soy protein to prevent soy protein from being coagulated and precipitated by calcium ion. Soy lecithin was first sonicated in calcium salt solution to envelop the calcium ion with a liposomal structure composed of lecithin. Then, the calcium-lecithin liposomes were added to soy protein solution. Precipitation and coagulation were not observed in this soy protein-lecithin liposome system containing 60 mM Ca²⁺. By this method, it was possible to prepare calcium fortified soy milk containing more calcium (120 mg/100g) than in cow's milk. These results suggest that this calcium-lecithin liposome system is useful for calcium fortification of soy milk.