不同分子结构的黄原胶对冷冻面团及面包特性的影响

为研究不同分子结构的黄原胶对冷冻面团品质和面包烘焙特性的影响,该研究将3种不同分子结构的黄原胶分别添加至面粉中制作面团,经冷冻贮藏后进行面包焙烤,测定面团发酵速率、流变学特性、热稳定性及面包比容、硬度、弹性等。结果显示：随着冻藏时间的延长,面团品质及面包烘焙特性均受到影响,添加黄原胶显著降低面团劣变程度、改善面包品质。流变学结果表明,添加黄原胶增加面团黏弹性,抑制淀粉糊化;质构结果表明,黄原胶的添加显著增加面包的弹性,降低面包硬度（P<0.05）;比容结果显示,黄原胶的添加可以显著增加冷冻面团面包的比容（P<0.05）;低分子量黄原胶对面包品质改善效果较好。综上,在冷冻面团中添加黄原胶,可以得到品质较好的冷冻面团面包,且较低分子量黄原胶（1 400 kDa）不仅能改善面包焙烤特性,还可以降低实际生产应用过程中的时间成本。     

焙烤冷冻面团专用油脂的制备

利用棕榈硬脂代替氢化油作基料,开发适用于焙烤冷冻面团的专用油脂生产技术及配方.将棕榈硬脂与大豆油按7:3比例混合进行酯交换反应,得到酯交换油脂用于制备焙烤冷冻面团专用油脂.通过单因素及正交实验确定的O/W型专用油脂最佳制备条件为:复合乳化剂(Tween80和SE比例为1:1)添加量12%(总重),乳化温度75℃,乳化时间1 min,油水比例4:6.在最佳制备条件下,O/W型专用油脂的乳化稳定性为95%,黏度为175 Pa·8.     

蛋氨酸在面包中应用研究

通过添加不同量蛋氨酸研究其对面粉粉质拉伸特性及对面包焙烤品质和贮存过程中老化程度影响。结果表明:蛋氨酸可改善面团流变特性,适量添加可增加面包体积和比容,改善面包芯硬度和组织结构,对增加面包蛋白质含量和持水能力、提高面包营养和感观品质有促进作用,同时能有效延缓面包老化,延长其货架期;蛋氨酸最适添加量为0．15％。     

变性淀粉对冷冻面团面包焙烤特性的影响

探讨了醋酸酯马铃薯淀粉对冷冻面团面包焙烤特性的影响。面团中分别添加不同质量分数(0%、5%、7.5%、10%、12.5%、15%)的醋酸酯马铃薯淀粉,在冷冻不同天数后,解冻进行焙烤,并对比容和全质构等参数进行测定。结果表明:醋酸酯马铃薯淀粉增大了面包的比容,减缓了面包在冻藏过程中比容的下降趋势,改善了面包的品质。     

复配型面包品质改良剂在板栗面包中的应用

首次利用面包品质改良剂对板栗面包的焙烤品质及延缓老化的作用效果进行了研究。依据各种改良剂对面包防老化效果的不同,确定出试验用改良剂为黄原胶、α-淀粉酶、单甘酯。分别以三种面包品质改良剂做单因素实验,实验结果表明:当黄原胶以板栗粉与面包粉总重量的0.5%、1%、1.5%、2%的比例添加到板栗面包中时,对板栗面包的感官品质及老化指标均产生了显著影响,当添加量为1%时,不但板栗面包具有良好的焙烤品质而且延缓了面包的老化;当α-淀粉酶按不同的比例添加时,在添加量为0.01%或0.005%时,板栗面包的抗老化效果及焙烤性能均较对照组好,但当添加量为0.03%、0.06%时,致使板栗面包芯发粘,面包醒发性能受阻;在单甘酯的单因素实验中,不同添加量的单甘酯对板栗面包的老化均有延缓作用,但对面包的焙烤品质均产生负面影响。选择几种改良剂的较优添加量做正交实验,实验结果表明:在板栗面包制作过程中按板栗粉及面包粉总重用量添加1.5%黄原胶、0%α-淀粉酶、0.3%单甘酯时,板栗面包具有良好的焙烤品质,且在贮存7d后,面包芯硬度比对照组下降44%,延缓了面包老化,延长了其货架期。     

鲢鱼酶解产物和鱼胶原肽对冷冻面团品质的影响

通过对比分析经0～6次冻融循环处理后面团的酵母菌存活率、发酵力保存率、醒发时间以及焙烤性质研究了鲢鱼酶解产物和鱼胶原肽对冷冻面团品质的影响。结果表明:添加鲢鱼酶解产物和鱼胶原肽的面团经6次冻融循环后,酵母菌的存活率分别为78.95%和61.80%,发酵力保存率分别为59.06%和46.67%,面团醒发时间分别为330 min和318min,均明显优于空白组;冻融后的面团与新鲜面团相比,焙烤的面包比容和弹性减小,添加了鲢鱼酶解产物和胶原肽不仅可缓解冷冻面团这一缺陷,还可改善面包色泽。结果证明了鲢鱼酶解产物和鱼胶原肽具有良好的酵母菌抗冻保护活性。     

几种改良剂对板栗面包焙烤品质及老化指标的影响

采用单因素实验,研究了黄原胶、α-淀粉酶、单甘酯三种面包改良剂对板栗面包焙烤品质及老化指标的影响。实验结果表明：黄原胶的添加对板栗面包的感官品质及老化指标均产生了显著影响,当添加量为板栗粉及面包粉总重的1%时,板栗面包具有良好的焙烤品质,贮存7天后,其硬度比对照组下降了9%;不同添加量的单甘酯对板栗面包的老化均有延缓作用,但对面包的焙烤品质均产生负面影响;当α-淀粉酶添加量为0.01%或0.005%时,板栗面包的抗老化效果及焙烤性能均好于对照组,但当添加量较高时,面包焙烤品质骤然下降。     

不同解冻方式对冷冻面团品质的影响

为改善冷冻面团品质,该文研究不同解冻方式对冷冻馒头面团和冷冻面包面团品质的影响。在对馒头粉与面包粉进行粉质特性评价的基础上,设置4组不同的解冻条件,对解冻引起的面团质量损失,解冻后面团的水分流动性以及酵母产气速率、面团膨胀体积进行测定;并进行馒头蒸制和面包焙烤,测定冷冻面团产品（馒头、面包）比容和质构、表皮和切片的色泽、切片内部纹理结构。结果表明：4℃缓慢解冻后制得的馒头或面包的比容最大,硬度最小,在微波解冻条件下的比容最小,硬度最大。解冻条件剧烈程度的增加不利于冷冻面团终产品的色泽保护,并且对面包的影响更大。缓慢解冻条件下得到的面团有较好的膨胀体积并且缓慢解冻更有利于减少面团中水分的流失。因此,通过缓慢解冻（4℃）可获得品质更优的冷冻面团及其产品。     

解冻温度和冷冻—解冻周期对冷冻面团焙烤特性的影响

冷冻技术最早用于贮藏和运输易腐败的食品，如蔬菜、水果、水产等。随着人们生活水平的提高和消费形式的改变，冷冻食品也由原来的初级加工品逐渐发展成深加工调理食品。冷冻技术早期用于面包工业是用来防止和延缓面包老化和变质的，而今主要用于冷冻未焙烤的面包团和冷冻成品面包，而冷冻面团在消费市场具有更大的吸引力。冷冻面团在发达发展得很快，美国有50％以上的超市面包房和零售店都采用冷冻面团加工面包，冷冻面团的零售业额接近65亿美元^[1]。冷冻面团与新鲜面团相比，由于面团配方、加工工艺、贮存条件以后处理方法等不同会造成面团品质的差异。西文中采用快速法面包面团制作工艺，以面团醒发时间和面包比容作为评价指标，研究贮藏一段时间后的面团的解冻温度和冷冻－解冻周期对它的质量的影响。     

硬脂酰乳酸钠对冷冻面团及其烘烤面包品质的影响

将硬脂酰乳酸钠(Sodium stearyl lactate,SSL)加入自制冷冻面团中,通过测定冷冻面团的流变学特性,以及冷冻面团烘烤面包的比容、质构特性和感官评分,研究SSL对冷冻面团及其烘烤面包品质的影响。结果显示,随着SSL添加量增加,冷冻面团弹性模量先升高后降低,损耗角正切tanδ先降低后升高,其中最优SSL添加量为0.20%;冷冻面团烘烤面包的硬度、咀嚼性先降低后升高,弹性、回复性、比容和感官评分先升高后降低,当SSL添加量为0.20%时,各指标达到各自的峰值,说明SSL改善了冷冻面团及其烘烤面包的品质。30 d冷冻储藏期内,加入SSL后,冷冻面团及其烘烤面包劣变幅度减小,说明SSL改善了其储藏特性。上述结果表明:加入SSL后,冷冻面团及其烘烤面包的品质及储藏特性得到改善,且最佳添加量为0.20%。     

流态起酥油对冷冻面团烘焙特性的影响研究

使用冷冻面团生产面包具有经济、方便、快捷,产品质量稳定的特点,冷冻面团的主要缺点是:面团的醒发时间随着冷冻储存时间的延长而延长,且面包比容小.起酥油系统是提高冷冻面包面团储存稳定性的关键因素之一,流态起酥油具有良好的功能性和流动性,可以满足食品工业自动化生产的要求.研究了一种流态起酥油对冷冻面团烘焙特性的影响,结果表明在冷冻面团研究开发中使用流态起酥油可以很好地改善冷冻面团面包的烘焙特性,使得用冷冻面团制得的面包与新鲜面包在制作参数和口感上相比没有很大的区别,冷冻面团在冷冻储存期间烘焙品质的下降可以用一种专用于冷冻面团的起酥油系统来弥补.     

Effects of milk proteins and gums on quality of bread made from frozen dough

BACKGROUND: Mixtures of milk proteins and gums incorporated into bread formulations may enhance the quality of bread and retard the deterioration of frozen dough. Our objective was to investigate the effects of mixtures of milk proteins (casein (C) and whey protein (W)) and gums (sodium alginate (A) and κ‐carrageenan (K) on the quality of bread made from frozen dough. We hypothesized that bread containing milk proteins and gums would be of improved quality. Milk proteins improve texture, moisture retention and specific volume, and reduce the size of ice crystals, while gums incorporated into the bread improve moisture retention, control water mobility and prevent the growth of ice crystals, so we hypothesized milk proteins and gums would suppress the quality deterioration of bread during frozen storage. RESULTS: We found that mixtures of milk proteins and gums proved effective with regard to the maintenance of the baking quality of frozen dough. Breads containing CA had a higher specific loaf volume than the control bread. The addition of WK enhanced crumb firmness during extended frozen storage. In sensory evaluation, the addition of WA and CA contributed to the improvement of baking quality, taste, texture and acceptability. CONCLUSION: These findings are consistent with the hypothesis that mixtures of milk proteins and gums improved baking quality by reducing the deterioration of frozen dough. These results indicate that the addition of CA and WA improved the bread quality and WK could effectively be used as an anti‐staling agent in bread. Copyright © 2009 Society of Chemical Industry     

γ-聚谷氨酸对全麦冷冻面团烘焙特性的影响

将γ-聚谷氨酸(γ-PGA)添加至全麦冷冻面团中,通过全麦粉持水率、酵母存活率研究γ-PGA的保水性和抗冻活性;以面包比容和质构等作为评价指标,研究γ-PGA对冷冻面团制作的全麦面包烘焙品质的影响。结果表明,添加γ-PGA可提高冷冻全麦面团的酵母存活率和发酵高度,增大全麦面包比容,减小面包硬度,促进面包芯中形成大气孔;贮藏3 d后,添加γ-PGA的全麦面包硬度和老化率显著降低(P<0.05),且γ-PGA的最佳添加量为1%。     

Effect of Amino Acids and Peptides on Mixing and Frozen Dough Properties of Wheat Flour

Free amino acids, peptides, and vital wheat gluten were investigated to determine their effect on the mixing and frozen dough baking properties of wheat flour. Addition of 1% cysteine and aspartic acid decreased and glutamic acid, histidine, arginine, and lysine increased the mixing tolerance of flour. Cystine, methionine, tryptophan, and phenylalanine increased but isoleucine, histidine, glycine, arginine, glutamic acid, aspartic acid, and lysine decreased loaf volume of nonfrozen dough breads. However cystine, methionine, tryptophan, and phenylalanine did not increase loaf volume of bread prepared from frozen dough. Vital wheat gluten increased mixing tolerance and bread loaf volume only for the nonfrozen dough. However, wheat gluten hydrolysate, corn, and bonito peptides decreased mixing tolerance after optimum mixing time and were effective in increasing loaf volume for both frozen and nonfrozen dough. As the amount of corn and bonito peptide increased, specific loaf volumes also increased. Addition of 2.5% corn peptide was most effective in increasing loaf volume of frozen dough bread. Crust browning and crumb stickiness increased, whereas crumb softness decreased with addition of peptides. Addition of less than 1% peptide did not adversely affect the aftertaste and off‐flavor of bread. These results suggest that addition of peptides are effective for improving the baking quality of frozen dough, whereas amino acids and gluten have no effect.     

Two-dimensional CFD modeling and simulation of crustless bread baking process

A special type of baking oven was developed where crustless bread was made by gently baking the dough at controlled temperature by spraying water at prefixed intervals on the surface of the dough. In this study, a two-dimensional (2D) CFD model for crustless bread during baking has been developed to facilitate a better understanding of the baking process. Simultaneous heat and mass transfer from the bread during baking was successfully simulated. It was found that core temperature of the bread reached at 95 °C at the end of baking where as moisture of the bread satisfies the normal bread quality. The model can be successively applied to study the unsteady heat and mass transfer from the crustless bread during baking.     

海藻酸丙二醇酯对全麦冷冻面团冻藏稳定性和烘焙特性的影响

本文研究了海藻酸丙二醇酯（Propylene glycol alginate,PGA）对全麦冷冻面团冻藏期间稳定性的影响,并探究了冷冻面团烘焙面包品质的变化。将0.3%的PGA加入全麦面团,通过测定冷冻面团冻藏1、2、3、4和5周后发酵特性、流变特性、蛋白质二级结构、微观结构以及面包的比容、质构特性、内部纹理结构和老化程度等,研究冷冻面团冻藏期间的稳定性。结果表明,随着冻藏时间的延长,添加PGA的冷冻面团在冻藏5周后具有较好的保水性,其发酵特性及流变特性相对于对照组均有所改善。冻藏5周后,对照组与PGA组其面包比容分别下降了19.872%和14.153%;面包硬度分别升高了64.186%和36.386%;气孔表面积分率分别下降了3.497%和2.300%;老化焓值分别上升了65.142%和42.416%。添加PGA能延缓冷冻面团冻藏期间β-折叠含量的上升和β-转角相对含量的下降。电镜扫描图（SEM）显示,随着冻藏时间的延长,PGA组的冷冻面团孔洞数目相比对照组明显减少且大小均匀,面筋网络结构完整性和连续性提高。研究结果表明PGA可以有效地延缓冷冻面团在冻藏期间的品质劣变,维持冷冻面团的稳定性并提高面包的烘焙特性。     

冷冻面团馒头研究进展

冷冻面团是通过速冻、冷藏方式对面团进行贮藏、运输处理的一种面团,这种冷冻面团推动了我国馒头、包子等中式面食制品快速发展,具有一定的发展潜力。本文介绍了冷冻面团馒头的生产工艺,总结了冷冻面团馒头品质的影响因素,探讨了目前我国改良剂对冷冻面团品质的改良效果,为提高冷冻面团馒头品质提供参考依据。     

Cryoprotective Role of Exogenous Trehalose in Frozen Dough Products

Aim of this work is to study the cryoprotective role of extracellular trehalose in the production of bakery products from frozen dough. Therefore, different levels of trehalose (up to 200 ppm) were incorporated in dough/bread samples made from white and whole-wheat flour, and their quality (loaf volume, weight loss during baking, crust and crumb color) and texture characteristics (dough, crust and crumb firmness) were examined during frozen storage. To investigate the role of trehalose on dough behavior, the sugar content (glucose, fructose, and sucrose) of dough samples composed with or without trehalose was monitored, and dough microstructure was also analyzed with scanning electron microscopy. The cryoprotective effect of trehalose was confirmed, and it was found proportional to its level for both flour types. Trehalose can improve dough behavior under freezing conditions in terms of bread volume and texture characteristics.     

鲢鱼酶解产物对冷冻面团品质特性的影响

为研究鲢鱼酶解产物对冷冻面团品质的影响，在面团中加入2%的系列鲢鱼酶解产物，分析冻融处理前后（第0和4次冻融循环，－18 ℃冷冻18 h，4 ℃解冻6 h为一次冻融循环）面团醒发和焙烤特性、流变特性及显微结构等的变化。结果表明，添加酶解产物能抑制冻融后面团醒发时间延长和面包比容下降，其中30 min酶解产物（SCMH-30）效果最好，醒发时间（121 min）显著低于空白组（170 min），面包比容（1.72 mL/g）显著高于空白组（1.54 mL/g），说明其抗冻效果良好；与空白组新鲜面团相比，酶解产物组面团的拉伸强度降低，黏附性和延展性增大，可能与酶解产物中还原性肽的负面作用有关；冻融后所有面团的拉伸强度降低，黏附性和延展性增大，而抗冻性较好的海藻糖组和SCMH-30组面团的变化幅度相对较小。电镜观察表明添加SCMH-30削弱了面团面筋形成，但能较好地维持冻融后面团面筋结构稳定；粉质特性分析说明添加SCMH-30使面粉的面团形成时间、稳定时间、粉质指数均显著降低，弱化度显著上升，而加入葡萄糖氧化酶则可减轻其对面粉粉质特性的不利影响。研究结果为鲢鱼酶解产物在改良冷冻面团中的实际应用及其有效调控提供了理论依据。