复合凝固剂制备彩色嫩豆腐工艺优化

为确定凝固剂谷氨酰胺转氨酶(TGase)与葡萄糖内酯(GDL)联合应用于彩色嫩豆腐制作时的较佳条件,通过响应面法对制备条件进行了优化。用彩色蔬菜汁作为豆腐的天然染料添加到豆浆中,分别以彩色嫩豆腐的弹性和凝聚性为主要响应值,建立了复合凝固剂浓度和点浆温度的响应面模型。结果表明,相对于复合凝固剂的浓度,点浆温度对于彩色嫩豆腐的质地影响更大;构建的响应面模型可靠,可以用于预测彩色嫩豆腐的弹性和凝聚性。根据响应面模型确定的制备彩色嫩豆腐的优化条件为:TGase添加量1.4g/L,GDL添加量1.7g/L,点浆温度53℃。采用感官评定和质构分析方法,对比了实验条件下制备的彩色嫩豆腐与市售内酯豆腐口感和质地差异,彩色嫩豆腐均优于内酯豆腐。     

内酯鱼肉豆腐的凝胶特性及感官品质研究

选用养殖量大、价值低的鲢鱼为原料,研究葡萄糖酸内酯(GDL)添加量、鱼蛋白质浓度以及盐添加量对内酯鱼肉豆腐凝胶特性和感官品质的影响。结果表明,鱼肉内酯豆腐的凝胶强度随蛋白质浓度和盐添加量的增加而显著增强;GDL添加量对内酯鱼肉豆腐的质构和感官品质影响显著,当GDL浓度低于0.07 g/g蛋白质时鱼肉蛋白不能形成良好的质构;在鱼肉蛋白浓度为0.9%,GDL添加量为0.10 g/g蛋白质,盐添加量为1.5%时,鱼豆腐有较好的感官品质。     

糖类对内酯豆腐质构的影响

为研究糖类对内酯豆腐的影响,向内酯豆腐中添加不同浓度的葡萄糖、麦芽糊精、可溶性淀粉和卡拉胶,并观察其质构的变化。结果表明,糖的种类和浓度对内酯豆腐的不同质构影响显著:葡萄糖对弹性影响较大,麦芽糊精对内聚性和黏性影响较大,可溶性淀粉对硬度和咀嚼性影响较大,卡拉胶对黏着力影响较大。SPSS主成分分析法研究表明,对内酯豆腐质构综合作用强弱顺序为卡拉胶>可溶性淀粉>葡萄糖>麦芽糊精。糖分子的分子质量、分子结构和表面电荷是影响内酯豆腐质构的重要因素。     

花生胡萝卜内酯豆腐工艺的研究

以花生和胡萝卜为原料,以葡萄糖酸-δ-内酯(GDL)为凝固剂,研制出花生胡萝卜内酯豆腐.产品具有蛋白质含量高,富含维生素A的营养特点.以产品的感官为主要评定指标,通过正交试验,确定了花生胡萝卜内酯豆腐的最佳配方和工艺参数.     

大豆品种对卤水豆腐和内酯豆腐加工特性的影响

以中黄13、小金黄、黑豆一号、东农53、五河野生大豆(新、陈)等不同品种的豆子为原料,根据卤水豆腐和内酯豆腐制作的基本工艺加工豆腐,以盐卤和葡萄糖酸-δ-内酯为凝固剂,利用感官评分、TPA质构分析、产率和营养素等指标,分析不同品种大豆对卤水豆腐和内酯豆腐加工特性的影响。结果表明,不同种类豆子加工两种豆腐的感官评分和质构分析结果差异均达极显著水平(p0.01),其中中黄13、小金黄、黑豆一号的感官评分和质构结果较高;五河野生大豆的卤水豆腐结构较为松散,而五河野生大豆(陈)内酯豆腐不能成型;结合产率、蛋白质和脂肪含量,综合分析得出小金黄、中黄13、黑豆一号这三个品种比较适合加工卤水豆腐;小金黄和黑豆一号比较适合加工内酯豆腐。     

芹菜花色豆腐的研制

本文研究了芹菜豆腐的制作工艺.通过单因素和正交试验研究芹菜汁与豆浆的比例,凝固剂葡萄糖酸-δ-内酯(GDL)添加量、凝固时间、凝固温度、淀粉添加量对豆腐品质的影响.试验结果表明,芹菜花色豆腐的最佳工艺条件:芹菜汁与豆浆的比例为1∶4,凝固剂葡萄糖酸-δ-内酯(GDL)添加量为0.4%,凝固时间为30min,凝固温度为95℃,淀粉添加量为0.5%.     

芹菜鱼肉豆腐的加工工艺研究

以大豆、鱼肉、芹菜为主要原料,葡萄糖酸-δ-内酯(GDL)作为凝固剂,研制出芹菜鱼肉豆腐。以产品的感官评价为指标,采用正交试验的方法。试验结果表明:在料水比为1∶6的豆浆中加入30%芹菜汁12mL,50%鱼浆20 g、85℃下添加10%葡萄糖酸-δ-内酯12 g,最终所得的产品颜色风味较好,营养丰富,具有一定的保健功效。     

不同方式处理的黄花菜对豆腐品质影响

为研究制粉、切段、榨汁3种处理方式的黄花菜对豆腐品质影响,以MgCl2为凝固剂制作黄花菜豆腐,采用流变仪对黄花菜豆腐断裂应力和屈服应变进行分析,并对黄花菜豆腐感官评分、得率、保水性、色差、质构特性、理化指标进行比较研究。结果表明：黄花菜汁豆腐感官评分、凝胶强度、得率、保水性等显著优于黄花菜粉豆腐和黄花菜段豆腐（p＜0.05）,分别为32分、2 505.17 g/mm、231.41 g、68%,同时黄花菜汁豆腐和黄花菜粉豆腐质构特性均显著优于黄花菜段豆腐（p＜0.05）,综合而言,添加黄花菜汁可更好地提升豆腐各项品质。为探究各项指标之间的相互影响,对黄花菜汁豆腐的重要特性做相关性分析,结果表明,豆腐得率与保水性和感官评分呈正相关,说明豆腐的得率越高,其保水性和感官评分越高;硬度、咀嚼性、胶着性、回复性、弹性、内聚性与得率、保水性和感官评分呈负相关,说明豆腐质构结果增大导致豆腐综合感官评分下降。     

响应面法优化燕麦内酯豆腐生产工艺

对燕麦内酯豆腐的生产工艺进行优化研究,通过正交实验和响应曲面分析考察燕麦粉和大豆分离蛋白粉的添加量对产品的硬度、表观黏度、弹性和凝胶性等质构特性的影响。结果表明:燕麦内酯豆腐的硬度、弹性和凝胶性受大豆蛋白添加量的影响较大,均随其含量的增加而增强。燕麦内酯豆腐的表观黏度则主要受燕麦成分的影响,并随其含量的增加而增大。当燕麦粉:大豆分离蛋白粉:水为9:10:300时,煮浆方式为直接加热煮沸5min,D葡萄糖酸-δ-内酯添加量为3g/kg,热凝固方式为80℃加热20min时,制得的产品表观黏度较小,硬度、弹性、凝胶性和持水能力最好。     

绿茶内酯豆腐的研制

以大豆、干茶叶为主要原料,以葡萄糖酸-δ内酯(GDL)为凝固剂,研制绿茶内酯豆腐。通过单因素实验和正交实验研究了豆浆浓度、豆浆与茶汁的混合比例、GDL添加量及凝固温度对绿茶内酯豆腐产品品质的影响。结果表明:当豆浆浓度为料水比1∶5,豆浆和绿茶汁的混合比例为8∶2,加热凝固温度为90℃,GDL添加量为0.20%时,绿茶内酯豆腐的品质最好,制得的豆腐呈浅黄色,口感细腻爽滑,具有绿茶特有的清香。     

紫甘蓝豆腐的工艺优化及其营养成分分析

以紫甘蓝和大豆为主要原料,选择主要影响豆腐品质的三个因素(紫甘蓝添加量、GDL添加量和凝固温度),以感官评分为响应值,通过响应面试验,建立回归模型,优化紫甘蓝豆腐加工工艺,并分析营养成分。结果表明,最佳工艺条件为:紫甘蓝添加量25%,GDL添加量0.18%,凝固温度为87 ℃,感官评分为86.40分。所得产品颜色为紫色,软硬适中,口感细腻,兼有普通豆腐的香气和紫甘蓝特有的甜味。紫甘蓝豆腐含水率为79.98%,蛋白质含量为7.70%,脂肪含量为29.95%。紫甘蓝豆腐中含有人体所需的8种必需氨基酸,占全部氨基酸的46.30%。其中苏氨酸含量最高,赖氨酸含量RC值最小,为第一限制氨基酸。     

豆渣添加量对豆腐凝胶特性和保水性的影响

采用超微处理的豆渣添加到豆浆中制作豆腐。凝固剂为葡萄糖酸内酯（内酯）和硫酸钙。研究结果表明,适量的豆渣可以提高硫酸钙豆腐的凝胶强度和粘附性,但对内酯豆腐来讲,降低了凝胶强度和粘附性。内酯豆腐和硫酸钙豆腐凝胶的硬度都表现出下降的趋势,而弹性和保水性在一定程度上得到增加。结果有益于提高豆腐营养价值,改善豆腐的品质。     

脂肪氧化酶缺失品种豆腐的感官和质构评价

豆制品的豆腥味与大豆中的脂肪氧化酶活性有关,为了降低豆腥味,培育出了脂肪氧化酶缺失类型的大豆品种.本研究分析了脂肪氧化酶缺失品种大豆(北农103)和普通大豆的脂肪氧化酶活性、可溶性蛋白含量、蛋白质亚基组成、Ca、Mg和植酸磷的含量等理化性质,并以这两种大豆为原料分别用卤水、石膏和内酯为凝固剂加工豆腐,对其豆腐产品进行了感官和质构评价.感官分析结果表明,脂肪氧化酶缺失品种(北农103)豆腐的豆腥味明显弱于普通大豆豆腐,由北农103大豆品种加工成的内酯和卤水豆腐的质构特性好于普通品种大豆,而石膏豆腐则相反.     

Yield and Quality of Tofu as Affected by Soybean and Soymilk Characteristics: Glucono-delta-lactone Coagulant

Nine light hilum soybean [Glycine max (L.) Merr] cultivars were used to study characteristics that affect yield and quality of tofu (soybean curd) coagulated with glucono-delta-lactone (GDL). Pressed and packed (nonpressed) curds were examined. Yield of tofu was not affected by size of beans. Protein and total solids in soymilk increased when protein and moisture increased in soybeans. Yield of pressed GDL tofu increased with protein content of soybeans (or soymilk) plus decreased calcium content. Fracturability of pressed GDL tofu increased with levels of phosphorus. Hardness of packed tofu increased with protein content in soymilk. Yield of pressed GDL tofu was 20% higher than CaSO₄ tofu.     

The effect of different varieties of soybean and calcium ion concentration on the quality of tofu

The Japanese food tofu (bean curd) was prepared by the traditional method using 15 varieties of soybeans. The tofu quality was evaluated on the basis of colour, taste and texture. The texture measurements were subjective and instrumental (hardness and cohesiveness).A slight variation in the texture of tofu was due to the 7S and 11S proteins in the soybean but an important factor affecting the texture of tofu was found to be the amount of calcium ions added during processing. The firmness and coarseness of the product increased with increases in the amount of calcium ions added and a linear relationship was found between the protein content of the beans and the calcium sulphate concentration required for good quality tofu.     

大豆油体对豆腐凝胶性质的影响研究

通过向脱脂豆浆中添加大豆油体,研究其对豆腐凝胶性质的影响。运用质构仪和离心机分别测定了豆腐凝胶的硬度和失水率。结果表明:非油体成分含量一定时,油体的加热时间延长(0~4min)对豆腐凝胶有利,体现在硬度增加和失水率降低;体系固形物含量一定时,油体与非油体成分含量之间存在一个最佳干基比值(0.143),此比值下豆腐凝胶性质最好,过高或过低凝胶性质均会减弱;室温下,随生豆浆放置时间的延长(0~60 min)制得的豆腐硬度略有下降,失水率没有明显变化。此外,与大豆油相比,油体因其独特的结构对豆腐凝胶有利。     

Influence of four different coagulants on the physicochemical properties,textural characteristics and flavour of tofu

The coagulation mechanism and quality characteristics of tofu depend on the choice of coagulant. The effects of using magnesium chloride (MgCl₂), calcium sulphate (CaSO₄), glucono-δ-lactone (GDL) and fermented soybean whey (FSW) as coagulants for tofu were investigated using solid-phase microextraction (SPME), two-dimensional gas chromatography coupled with mass spectrometry (GC×GC-MS), scanning electron microscopy (SEM) and analysis of textural characteristics and physicochemical properties. Results showed that GDL tofu exhibited the highest yield (202 g 100 g⁻¹) and moisture content (76.3%). FSW tofu had the highest protein content (18.5%), amino acid content (15.85%) and textural properties. GC×GC-MS analysis revealed the number of 49, 44, 55 and 63 flavour substances, respectively. In sensory evaluation tests, GDL tofu was reported to possess a smooth surface and white colour. The microstructure of FSW tofu was dense and uniform. Through the above technical researches, the study suggested FSW gave tofu the best quality, more unique flavour and more potential popular among consumers.     

Comparison of Two Small-Scale Processing Methods for Testing Silken Tofu Quality

In developing a simple, reliable, small-scale method to assess silken tofu quality in our soybean improvement program, we examined two processing methods and two coagulants, glucono-δ-lactone (GDL) or nigari (magnesium chloride) in two experiments. Silken tofu was prepared from a commercial soybean variety (expt 1) or seven soybean varieties (V1–V7) which were grown and harvested together (expt 2). The soybeans were soaked overnight (the soak method, with 55 g soybeans) or ground dry first (the dry method, with 60 g soybeans) before processing. The quality of the silken tofu was evaluated and compared among varieties and coagulant-processing methods and their interactions. Moisture and protein content in soymilk and soybean seeds, soymilk yield and protein and solid recovery in soymilk were determined. Compared with the dry method, the soak method allowed faster soymilk extraction, produced soymilk with lower solid and higher protein content and firmer silken tofu with either GDL or nigari as coagulant. Depending on whether nigari or GDL was used as coagulant, the soak method also produced silken tofu with the highest or the lowest water loss which correlated strongly and negatively with tofu hardness (r?=??0.93***). Differences were detected among varieties for the key quality attributes. Taken together, the soak method with GDL as coagulant would be the preferred combination to use to assess tofu quality.     

Instrumental Textural Characteristics of Restructured Carrot Cubes

Studies were carried out on the instrumental textural evaluation of restructured carrot cubes. The experiment was conducted by incorporating different levels of alginate, glucono delta lactone (GDL), and calcium salt to the carrot pulp. Investigations showed that as pulp level increased from 0 to 90%, there was a corresponding decrease in failure stress, failure strain, and deformability modulus. Instrumental textural profile analysis (TPA) parameters viz. hardness, springiness, gumminess, cohesiveness, chewiness, and resilience also showed a similar trend. Effect of formulation variables, i.e., alginate, GDL, and calcium salt on hardness (response variable) were evaluated by the application of response surface methodology. All the three ingredients showed a significant (P < 0.05) influence on hardness of carrot gel. Heat treatment of restructured carrot samples resulted in an increased hardness, cohesiveness, gumminess, and chewiness while springiness, cohesiveness, and resilience decreased. The data indicated that the shrinkage during thermal treatment may be responsible for the change in textural attributes. The authors concluded that a thermally stable restructured product with appreciable textural integrity can be obtained from carrot pulp.     

加工工艺对北方豆腐品质特性的影响

分别以生浆法、熟浆法、热水套法3种工艺制备北方豆腐,以出品率、保水性为指标,获得最佳制浆方式后,研究磨浆料液比、凝固温度、Mg Cl2溶液添加量、凝固时间对北方豆腐品质特性的影响以及出品率、保水性与质构特性的相关性。结果表明:熟浆法制成北方豆腐的出品率、保水性明显高于生浆法和热水套法;豆腐工艺的最佳优化条件为磨浆料液比1∶7(g/m L)、凝固温度80℃、0.6 mol/L?Mg Cl2溶液添加量18 m L/L、凝固时间20 min,制作的北方豆腐出品率和保水性均最高;根据相关性分析得出:不同加工条件下,硬度、内聚性及回复性与北方豆腐出品率、保水性均呈负相关,咀嚼性、胶着性及弹性与北方豆腐出品率、保水性均呈正相关。