酸性面团对普通面包和豆渣面包品质的影响

利用活性酸奶乳酸菌发酵制作酸性面团，在普通面包与豆渣面包中分别加入30％～40％(以面粉计)的这种酸性面团后，面包体积、口感、风味、保鲜期和营养品质得到了明显改善。     

Sensory Analysis of Whole Wheat/Soy Flour Breads

ABSTRACT: Breads containing 0% to 40% defatted soy flour, 35% to 100% whole wheat flour, and 0% to 35% white bread flour were prepared. Beany or bitter flavor ratings for the yeast-leavened breads containing up to 30% soy flour were not significantly different from the control whole wheat bread. A high-quality yeast was the most important factor in reducing the beany taste of the bread. Addition of ascorbic acid significantly increased yeasty flavor, and there was a strong inverse correlation between beany and sweet flavors. These studies suggest that an appealing, nutritious bread containing up to 30% to 40% soy flour can be prepared in an easy and economical manner using equipment available in home or institutional kitchens.     

米酒老面发酵工艺对馒头品质的影响

为探究发酵时间、发酵温度、米酒添加量对米酒老面和米酒老面馒头品质的影响,通过3,5-二硝基水杨酸分光光度法、面筋指数测定仪、pH计、小米容积置换法、白度仪、硬度仪和感官评分等方法,以米酒老面的pH值、还原糖含量、湿面筋含量和面筋指数以及米酒老面馒头比容、白度、硬度和感官为评价指标.结果表明:随着米酒老面发酵时间的延长,...     

Characterization of the Bread Made with Durum Wheat Semolina Rendered Gluten Free by Sourdough Biotechnology in Comparison with Commercial Gluten‐Free Products

Durum wheat semolina was fermented with sourdough lactic acid bacteria and fungal proteases aiming at a complete gluten hydrolysis. The gluten‐free (GF) semolina, added with naturally GF ingredients and structuring agents, was used to produce bread (rendered GF bread; rGFB) at industrial level. An integrated approach including the characterization of the main chemical, nutritional, structural, and sensory features was used to compare rGFB to a gluten‐containing bread and to 5 commercial naturally GF breads. High‐performance liquid chromatography was used for free amino acids (FAAs), organic acids, and ethanol analysis. A methanolic extract was used for determining total phenols and antioxidant activity. The bread characterization also included the analysis of dietary fibers, mycotoxins, vitamins, and heavy metals. Beyond chemical analysis, nutritional profile was evaluated considering the in vitro protein digestibility and the predicted glycemic index, while the instrumental texture profile analysis was performed to investigate the structure and the physical/mechanical properties of the baked goods. Beyond the huge potential of market expansion, the main advantages of durum wheat semolina rendered GF can be resumed in the high availability of FAAs, the high protein digestibility, the low starch hydrolysis index, and the better technological properties of bread compared to the commercial GF products currently present on the market. Vitamins, minerals, and dietary fiber profiles are comparable to those of gluten‐containing wheat bread. Also the sensory profile, determined by a panel test, can be considered the most similar to those of conventional baked goods, showing all the sourdough bread classic attributes.     

Free D- and L-Amino Acid Evolution During Sourdough Fermentation and Baking

The evolution of free D- and L-amino acids in sourdoughs started with various lactic acid bacteria (LAB) and yeasts was studied. Lactobacillus brevis subsp. lindneri CB1 and Lactobacillus plantrum DC400 had high proteolytic activity. During sourdough fermentation, Saccharomyces cerevisiae 141 and Saccharomyces exiguus M14 sequentially utilized free amino acids produced by bacterial activity. Due to increased cell yeast autolysis, more S. exiguus M14 inocula caused more free amino acids which were partially utilized by LAB without causing hydrolysis of wheat flour protein. D-alanine, D-glutamic acid and traces of other D-isomers were observed in sourdoughs fermented with L. brevis subsp. lindneri CB1 and S. cerevisiae 141. Free total D- and L-amino acid content decreased by more than 44% after baking the sourdoughs. No abiotic generation of new D-amino acid isomers was detected in the baked sourdoughs.     

Changes in the Physicochemical Properties of Wheat- and Soy-containing Breads During Storage as Studied by Thermal Analyses

ABSTRACT: Adding soy ingredients to baked products influences textural and sensorial properties. The changes in physical properties of bread modified with soy flour during 7-d storage at ambient temperature were investigated using thermoanalytical techniques (differential scanning calorimetry and dynamic mechanical analysis). An increase in loaf density, moisture content, and FW content, and a decrease in amylopectin recrystallization were observed with increased addition of soy flour. Addition of soy shifted the main thermal transition (0 °C, mainly due to ice melting) to slightly lower temperatures (both in differential scanning calorimetry and dynamic mechanical analysis analysis) and decreased its temperature range (increased homogeneity). These observations suggest a role for soy in modulating bread staling.     

青方腐乳发酵过程中大豆异黄酮的转化研究

本文比较了青方、红方、白方和低盐红腐乳中大豆异黄酮组成和含量差异,并对青方腐乳发酵过程中大豆异黄酮含量和构型变化规律进行研究。结果表明,四种类型腐乳中大豆异黄酮基本以苷元形式存在,青方腐乳大豆异黄酮含量明显低于其他类型腐乳,仅为红方腐乳的33.01%,从单一异黄酮来看,大豆苷元和染料木素在四种类型腐乳中的含量明显高于黄豆黄素;青方腐乳发酵过程中大豆异黄酮转化研究发现,白坯中大豆异黄酮以糖苷型为主,染料木苷含量高于大豆苷和黄豆黄苷,前酵过程中糖苷型大豆异黄酮转化为苷元型大豆异黄酮,盐腌过程中糖苷型大豆异黄酮含量有轻微降低,发酵过程中苷元型大豆异黄酮总量在后酵前30 d显著下降,其中大豆苷元可能部分转化为雌马酚,导致青方腐乳大豆异黄酮含量明显低于其他类型腐乳,对其转化物质需进一步鉴定。     

响应面法优化汉堡面包的种面发酵工艺

为优化选出抑青霉菌效果最好的汉堡面包种面发酵基质及工艺,本文通过单因素实验结合Box-behnken响应面试验进行优化,以种面对青霉菌的抑菌率作为评价指标,选出最优的发酵剂和糖种类等发酵工艺,并对最优条件下制作的汉堡面包的理化性质、微生物数量、感官、质构以及保质期等指标进行测定.结果表明,最优发酵工艺为种面中添加乳酸菌...     

Prevalence,Genetic Diversity,and Technological Functions of the Lactobacillus sanfranciscensis in Sourdough: A Review

The use of sourdough as a leavening agent in bread making is a very old method that can be traced back to ancient times. Sourdoughs harbor a complex microbiota that is affected by multiple factors including factors related to cereal plants, grains, and sourdough processing techniques. Lactobacillus sanfranciscensis is the key autochthonous bacterium of the traditional sourdough microbiota and it is said to be “sourdough adapted” species. Despite the great dominance of this bacterium in sourdoughs, the origin of this species still remains unclear. Lactobacillus sanfranciscensis positively influences all aspects of sourdough and fermented foods. However, the positive influence of this species on sourdough is a strain‐dependent characteristic. The first purpose of this review was to discuss factors affecting the microbiota of sourdoughs with particular emphasis on reasons behind the remarkable prevalence of L. sanfranciscensis in this ecological niche. The second objective was to discuss the genotypic and phenotypic classification of L. sanfranciscensis strains and the influence of this species on technological and functional characteristics of sourdough including its influence on rheological properties of dough and bread characteristics, texture, aroma, and shelf‐life through the inhibition of fungal growth.     

Physicochemical Properties of Partbaked Breads

In this current study eight partially-baked breads were studied and compared in terms of a number of physicochemical characteristics: moisture distribution, density, RVA patterns, starch gelatinization, and retrogradation, amylose lipid complex formation and X-ray diffraction patterns. The samples were different in terms of total moisture content (from 32 to 38%) and moisture distribution in the cross section of the samples, starch retrogradation level (from 0.9 to 4.5 (J/g)) and RVA patterns. DSC experiments were carried out to determine the level of starch gelatinisation. The results showed that all starch granules in the eight partbaked breads were fully gelatinized under the conditions used and there was no intact starch granules left in the systems. Therefore, the second phase of baking will not be of great importance in terms of setting the structure and texture of the crumb of a product made from partbakaed bread. The role of the second phase of baking will be to a large extent the generation of flavor, crust, and coloration in the bread.     

Utilization of Transglutaminase to Increase the Level of Barley and Soy Flour Incorporation in Wheat Flour Breads

ABSTRACT: This study investigated the possibility of incorporating barley or soy flour into wheat flour using transglutaminase (TG)-catalyzed cross-linking, without deterioration in bread quality. A Farinograph and texture analyzer were used to examine mixing properties and extensibility of doughs, respectively. Addition of increasing levels of barley/soy flour (with and without TG) increased Farinograph water absorption in the soft and hard wheat cultivars studied. Dough resistance increased and extensibility decreased with TG treatment. TG showed great promise in processing of bread supplemented with barley flour, even at a very low level (0.25%, wt/ wt), but did not notably improve the quality of soy flour-supplemented breads.     

酸面团发酵过程中蛋白质分解及多肽形成的变化规律

本文以小麦粉,酵母菌和植物乳酸菌M616(Lactobacillus plantarum M616)为原料制备酸面团,酵母发酵面团以及乳酸菌发酵面团,研究酸面团发酵过程中蛋白的分解及肽的形成规律,采用SDS-PAGE分析酸面团发酵过程中蛋白质的组成变化,利用Bradford法分析蛋白质含量的变化,并通过HPLC研究蛋白组分降解形成多肽的含量变化。结果表明,酵母菌对面团中蛋白质几乎没有降解作用,植物乳酸菌M616在面团发酵过程中对面团蛋白具有较强的降解作用,表现为各蛋白含量随发酵时间的进行逐步减少,且在4~10 h之间变化最为显著。其中可溶性蛋白和中分子量麦谷蛋白的降解最为明显,醇溶蛋白含量在0~10 h之间逐渐增加后逐渐减少。对发酵前后多肽含量变化分析发现植物乳酸菌可以明显促进面团中多肽的形成和含量的增加。     

燕麦酸面团发酵剂的冻干和储藏对面包风味的影响

应用固相微萃取技术(SPME)和气相色谱- 质谱联用技术(GC-MS)研究发酵剂冷冻干燥(冻干)前后面包中的挥发性风味物质,考察发酵剂的冻干和储藏对燕麦酸面包风味的影响。结果表明：旧金山乳杆菌发酵燕麦酸面包中的挥发性风味物质共87 种,主要包括酸类、醇类、醛类、酯类、酮类、脂肪烃类,以及一些芳香族和杂环类化合物。酸类物质的含量最高,其次是醇类、芳杂环类和醛类物质。在发酵剂冻干和储藏过程中,醛类和醇类物质先增加后减少,酸类、酯类、酮类和脂肪族化合物先减少后增加,芳杂环类物质含量则持续升高。燕麦酸面团发酵剂冻干后以及储存30d 制得的面包依然具有丰富的风味。乳酸菌和酵母菌的竞争作用导致乙酸和乙醇含量呈现相反的变化。糠醛含量持续升高,而己醛则在冻干后显著减少,并在存储30d 后消失。     

Sourdough Lactic Acid Bacteria Effects on Bread Firmness and Stalin

Lactobacillus sanfrancisco CB1 and Lactobacillus plantarum DC400 were the most proteolytic and amylolytic strains studied. Breads started with LAB and yeasts had higher volumes than the baker's yeast-started bread. One bread with the highest initial firmness (Saccharomyces cerevisiae 141- L . plantarum DC400 starter) had the lowest final firmness. Breads produced with LAB showed the lowest enthalpy throughout 144 h. After 24 h storage the associations of S. cerevisiae 141 and L. sanfrancisco CB1 or L. plantarum DC400 gave a very low percentage increase of enthalpy compared to that from yeast alone. The enthalpy increased markedly when other LAB, neither proteolytic nor amylolytic, were used.     

融合魏斯氏菌和异常威克汉姆酵母混菌发酵荞麦酸面团馒头的香气物质特征

应用分离自我国酒鬼酒曲中的融合魏斯氏菌和梅兰春酒醅中的异常威克汉姆酵母进行混菌发酵,通过测定菌株生长曲线探索两株菌的共生作用,采用固相微萃取结合气质联用(SPME-GC-MS)和气相电子鼻技术,对比混菌发酵酸面团(MBF)和单菌发酵酸面团及其荞麦馒头风味化合物的差异性。结果表明,在MBF中乳酸菌、酵母菌菌落数分别达到9.38 log CFU/g、8.51 log CFU/g,两株菌具有良好的共生关系。发酵后荞麦酸面团的主要特征风味物质为乙醇、乙酸、乙酸乙酯、乙偶姻和异戊醇。与酵母菌单菌发酵荞麦酸面团馒头相比,混菌发酵馒头中酯类物质相对含量从5.27%提高到9.53%,结合ROAV分析,混菌发酵荞麦馒头的风味强度明显高于单一乳酸发酵和单一酵母发酵,赋予馒头更浓郁的酒香和果香,感官评定证实其整体可接受度高于其他组。     

Development of Co-Culture Sourdough Systems for Improving Bread Quality and Delaying Staling

Six different blends of lactic acid bacterial cultures (Lactobacillus plantarum or Pediococcus cerevisiae) combined with Saccharomyces cerevisiae were used as co-culture for preparing sourdoughs. These prefermented sourdoughs were applied for producing pan breads. Acidification power, leavening ability, and microbial counts were conducted at different sour fermentation intervals. The highest acidification power in sourdoughs were recorded when 2% w_d/w_d (dry weight of cells/dry weight of flour) of either L. plantarum or P. cerevisiae was used in combination with 2% w_d/w_d S. cerevisiae. The leavening ability of sourdoughs was significantly (p < 0.05) enhanced by increasing the addition percentage of the studied LAB. According to staling rate, physical, and sensory characteristics, the best two treatments were obtained when the co-culture of 2% w_d/w_d S. cerevisiae with 4% w_d/w_d L. plantarum or 4% w_d/w_d P. cerevisiae were used. These two treatments were successfully applied in production of the flat bread. According to staling rate, physical and sensory characteristics, sourdough prefermented with 2% w_d/w_d S. cerevisiae combined with 4% w_d/w_d L. plantarum was the best treatment for preparing of flat bread. Overall the co-culture of L. plantarum and with S. cerevisiae might be a useful tool for preparing sourdough starter that was most effective for improving sensory and physical properties of both pan and flat bread. In addition it can help extend the shelf life by delaying bread staling and inhibiting mold spoilage.     

大豆异黄酮及其苷元的研究进展

大豆异黄酮是一种天然的雌激素,是大豆生长过程中的次级代谢产物,其主要位于大豆种子的子叶和胚轴中。其中97%左右以糖苷形式存在,其余以苷元形式存在,大豆异黄酮苷元是其发挥主要功能活性的形式。目前大豆异黄酮的常规提取方法包括有机溶剂萃取法、超声波辅助提取法、微波辅助提取法、超临界流体萃取法、亚临界水法等。研究表明,大豆异黄酮及其苷元具有一定的生理功效,包括预防心血管疾病,预防骨质疏松,抗肿瘤和神经保护等。本文在介绍大豆异黄酮及其苷元的组成、化学结构特性的基础上,详细综述了大豆异黄酮及其苷元的研究概况、提取工艺和主要功能活性,并展望了该领域今后的发展趋势和有待加强的研究方向,旨在为大豆异黄酮及其苷元产业化开发和深入研究其临床应用价值提供参考依据。