冻融循环下抗冻多肽对冷冻马铃薯面团的品质保护及作用机理

通过将抗冻多肽添加到马铃薯面团中,研究在冻融循环条件下抗冻多肽对冷冻马铃薯面团品质的保护作用。在冻融循环条件下测定抗冻多肽（tilapia scale antifreeze peptides,TSAPP）对冷冻马铃薯面团的比容、发酵性能、失水率、淀粉糊化度、质构特性、水分分布与迁移等的影响及作用机理。结果表明：添加1% TSAPP使马铃薯面团比容增大、发酵时间缩短、淀粉糊化程度高、失水率降低;质构分析显示,与空白对照组相比,1% TSAPP组的马铃薯馒头硬度、咀嚼性和胶黏性分别下降了29.96%、26.99%、28.30%;核磁共振分析显示,TSAPP可以影响冷冻马铃薯面团中的水分状态使深层结合水含量增加,半结合水含量减少;TSAPP还能抑制水分流失,提高马铃薯面团的持水力。结论：抗冻多肽可作为冷冻马铃薯面团产品的低温保护剂。     

乳酸菌发酵对面包品质的影响

本论文将按两种比例混合的混合乳酸菌发酵剂按22.3%和44.6%添加到面包制作中,测定发酵面团及面包比容、面包感官、面包质构(如硬度、弹性、咀嚼性等).实验结果表明,添加22.3%的发酵剂有助于面团发酵,增加发酵面团比容,添加量达44.6%的发酵剂却会降低面团的比容;烘烤后,乳酸菌发酵的面包比容小于未添加乳酸菌制作的对...     

食品添加剂对冷冻面团面包品质的影响

采用快速发酵法制作冷冻面团面包,研究了酵母、海藻糖、抗冻改良剂(F-99)和硬脂酰乳酸钠(SSL)等添加剂对冷冻面团面包质构和感官品质的影响,通过单因素和正交试验,优化确定了不同添加剂的最佳添加量。结果表明:添加适量的酵母、海藻糖、F-99和SSL等添加剂能提高面包弹性、降低硬度等,4种添加剂添加量对冷冻面团面包品质影响顺序为:海藻糖SSL酵母F-99。最佳添加剂配方为:酵母1.8%,海藻糖5%,F-99 6%,SSL 0.4%,制作的冷冻面团面包水分含量42%、比容5.1m L/g、酸度4.4o T、硬度3.13N、弹性11.93mm、胶黏性2.5N、咀嚼性29.88m J,面包质量符合国家规定标准,硬度、弹性等指标明显优于对照制品。     

刺槐豆胶对冷冻面团水分分布及面包品质的影响

将刺槐豆胶(Locust bean gum,LBG)加入冷冻面团中,利用核磁共振测定冷冻面团的水分分布及状态,扫描电镜测定面团的微观网络结构,扫描仪及质构仪对面包的纹理结构和质构特性进行分析,研究持水性强的刺槐豆胶对冷冻面团水分分布状态的改善作用,探讨面团微观网络结构,纹理及质构特性与水分分布的关系。结果显示:随着冷冻面团冻藏周数的增加,对照组面团中深层次结合水占比由17.40%下降至14.40%,自由水占比上升了3.40%,面筋蛋白包裹淀粉颗粒能力逐渐下降,淀粉颗粒的排布逐渐混乱,面团的发酵速度逐渐缓慢,冷冻面团烘烤面包的纹理结构不再均一有序,硬度增大,弹性下降。加入LBG后,深层次结合水占比由17.20%下降至15.40%,自由水占比上升了2.70%,面筋蛋白网络结构及其烘烤面包劣变幅度减小,说明LBG有效的延缓了面团中深层次结合水的转化,改变了冷冻面团的储藏特性。     

花生乳稳定性研究

研究几种乳化剂和增稠剂对花生牛奶稳定性的影响,结果表明蔗糖脂肪酸酯、单硬脂酸甘油酯、黄原胶、瓜尔豆胶、结冷胶在适宜的添加量时,对花生乳稳定性都有良好的促进作用。单因素分析优选结果为:蔗糖脂肪酸酯与单硬脂酸甘油酯复配比例为2:3,总添加量为0.06%,黄原胶0.04%,瓜尔豆胶0.02%,结冷胶0.004%。     

挤压糙米粉对糙米面团及面包品质的影响

将糙米粉（生粉）与挤压糙米粉（熟粉）分别按照生熟比10 ∶ 0,9 ∶ 1,8 ∶ 2,7 ∶ 3,6 ∶ 4比例混合制备成混合粉,然后将糙米混合粉与谷朊粉按照8 ∶ 2的比例混合制备糙米面团及面包。研究挤压糙米粉添加量对糙米面团及面包品质的影响。结果表明：随着挤压糙米粉添加量的增加,糙米面团网络结构越疏松,孔隙越大,黏弹性均比未添加挤压糙米粉的面团低,糙米面包比容先减小后增大。添加挤压糙米粉后,糙米面包的硬度降低,感官评分值升高。放置1～4 d,糙米面包的硬度增加值随着挤压糙米粉添加量的增加而降低,面包弹性均比未添加挤压糙米粉面包的高。挤压糙米粉的添加有利于面包延缓老化,提升品质,当生熟比为6 ∶ 4时,面包品质最好。     

冷藏对面团发酵及面包品质的影响

通过测定酵母发酵力、面包比容、质构及风味物质等参数,研究了不同冷藏温度、冷藏时间及面团冷藏前醒发处理时间对面团发酵及面包品质的影响。结果发现,面团前处理时间越短,冷藏醒发温度越低,酵母持续产气时间越长;增加前处理时间以及提高冷藏醒发温度,可使面团更快达到醒发终点。增加面团前处理时间或提高冷藏发酵温度,可有效改善面包芯硬度和弹性。通过GC-MS测定的风味物质结果显示,冷藏会增加面包风味物质含量,并随着冷藏时间增长而增加。     

麦芽糖淀粉酶对面包品质及面团特性的影响

研究枯草芽孢杆菌来源的麦芽糖淀粉酶对面包品质及面团特性的影响,为深入了解酶制剂在烘焙产品中的作用提供理论依据。本实验主要研究了麦芽糖淀粉酶(添加量0%、0.02%、0.04%和0.06%)对面包比容、质构、贮藏期间面包保水性、质构、感官品质及面团流变学特性的影响。结果表明:面包保水性随麦芽糖淀粉酶添加量的增加而显著提高(P<0.05),而且麦芽糖淀粉酶能显著延缓面团黏度和回生值的增加(P<0.05),改善面团品质。当面包贮藏天数的增加,麦芽糖淀粉酶还能延缓面包硬度和咀嚼性的增加,减缓贮藏期面包品质下降(P<0.05)。其中,添加0.04%的麦芽糖淀粉酶能够明显延缓面包老化,对面团淀粉糊化特性影响较小。面包贮藏第7 d时,能减少水分损失36.92%,保持面包弹性。因此,麦芽糖淀粉酶能够延缓面包老化和面包品质下降。     

低场核磁共振分析仪研究添加剂对冷冻面团 持水性的影响

为提高面团的持水性以降低面团在冷冻过程中的水分迁移。利用低场核磁共振分析仪(NMR)研究34种面团常用添加剂的持水特性。对于发酵面团,提高面团持水性能力排在前5位的依次为双乙酰酒石酸单(双)甘油酯(DATEM)、瓜尔豆胶、硬脂酰乳酸钠(SSL)、抗坏血酸(VC)、三聚磷酸钠,它们能使深层结合水的比例从19.29%分别提高到28.66%、25.80%、25.10%、24.90%、23.86%。对于未发酵面团,提高面团持水性能力排在前5位的依次为三聚磷酸钠、羟甲基纤维素钠(CMC)、瓜尔豆胶、VC、六偏磷酸钠,它们能使深层结合水的比例从17.27%分别提高到23.80%、23.35%、23.16%、23.07%、22.84%。     

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。     

结晶果糖的发酵性能和焙烤产品工艺优化

以酵母菌体生物量和细胞生长残糖量为指标,比较了酵母对结晶果糖与蔗糖发酵能力;以感官评价、质构和比容为指标,对面包生产工艺进行优化。结果表明：结晶果糖和蔗糖的发酵性能相似,实验获得了以果糖作为甜味剂的优化工艺和配方组成,使用食品添加剂可以有效改善面包的品质,最佳添加剂配比为SSL 0.1%、DATEM0.1%、SE 0.3%、瓜胶0.2%、CMC 0.3%、真菌α-淀粉酶480U/100g面粉,最适发酵/醒发时间为40min/50min,30℃。在此工艺及配方下,面包品质得到明显改善,添加结晶果糖的面包能达到与添加绵白糖的面包同样的品质,且在温度20℃、相对湿度55%环境下无包装保存3d后,面包内部仍保持较佳品质。     

乳化剂、亲水胶体及谷朊粉对方便湿面品质的影响

为解决方便湿面因水分含量高易发生老化,硬度增加、弹性下降和口感变差等问题,采用三类添加物即乳化剂（单甘酯、硬脂酰乳酸钠、蔗糖酯）、亲水胶体（黄原胶、瓜尔胶、羧甲基纤维素钠）和谷朊粉对方便湿面面片的色泽、蒸煮品质及储藏期间的质构拉伸特性和水分分布的影响开展了研究。结果表明：蔗糖酯将面片的亮度从95.26显著提高到96.78;三类添加物均显著降低了蒸煮损失,其中添加0.20%硬脂酰乳酸钠使方便湿面的蒸煮损失从5.81%降低至3.00%;储藏期间,添加0.40%单甘酯可使方便湿面的硬度从4 787.44 g降低至2 904.95 g;三类添加物均显著提高了方便湿面的拉伸特性,其中添加0.20%蔗糖酯使方便湿面的拉伸力从17.94 g提高到24.13 g;从水分分布可以发现,乳化剂抑制了结合水的流动,增大了结合水的含量,减小了自由水的流失。综上所述,添加三类添加物均延缓了方便湿面在储藏期间淀粉的老化,使方便湿面的蒸煮损失降低、硬度减小和弹性增加,进而改善了方便湿面的品质,其中添加0.40%的单甘酯和0.30%瓜尔胶的效果较好。     

Pre-Germinated Brown Rice Substituted Bread: Dough Characteristics and Bread Structure

Pre-germinated brown rice (PGBR) having the germ length of 0.5–1.0 mm is produced as a healthy food by immersing the brown rice in water. In this article, various additives were used for making PGBR breads, and suitable combinations of PGBR and additives for breadmaking were evaluated to provide PGBR bread with high functional properties. The 30% of the wheat flour was substituted with PGBR (PGBR 30), and combined additions of phytase (PHY), hemicellulase (HEM) and sucrose fatty acid ester (SE) to PGBR 30 improved the bread qualities with more suitable dough properties, as compared with the sample without their addition. During fermentation, the amounts of gas leaked from the PGBR 30 dough were suppressed by the additions. PHY and HEM hydrolyzed the phytate and hemicellulose in PGBR, and the maturity and extensibility of the PGBR 30 dough were caused by the activated yeast with formed phosphate and decomposed bran, making the large loaf volume and softness of breadcrumbs during storage. In addition, SE accelerated the dough tolerance to mixing or fermentation with the emulsifying ability. Therefore, the combined additions with PHY, HEM, and SE to PGBR 30 improved the dough and bread qualities.     

品质改良剂对复合杂粮面包粉流变学特性的影响

以营养优化后的复配杂粮面包粉为原料,选择谷朊粉、硬脂酰乳酸钠（sodium stearoyl lactylate,SSL）、黄原胶及瓜尔豆胶为品质改良剂,通过单因素试验研究4 种品质改良剂对杂粮面包粉流变学特性的影响,在此基础上通过响应面分析试验,以面团综合得分为响应值,得出复合改良剂的最佳配方为：1 000 g杂粮面包粉（杂粮粉占比34%）为基重,谷朊粉3.77%、SSL 0.35%、黄原胶1.08%、瓜尔豆胶0.35%。各因素对杂粮面包粉综合评分的影响大小为：黄原胶添加量＞谷朊粉添加量＞瓜尔豆胶添加量＞SSL添加量。添加复合改良剂后杂粮面包粉的稳定时间由4.7 min上升到14.2 min,形成时间由3.9 min上升到了13.3 min,粉质指数从56上升到192。复配杂粮面包粉流变学特性有很大程度改善,达到制作杂粮面包的粉质要求。     

Rheological properties of rice pasta dough supplemented with proteins and gums

Rheological properties of rice pasta dough were studied by creep-recovery tests for various formulations containing guar gum (0.5%), casein (1%), and egg white (1%) mixtures. Non-gelatinized rice semolina (RS) was also mixed with gelatinized RS in different ratios (0, 25, 50, 75 and 100%) for each formulation. The effects of gelatinization, gum and proteins on pasta dough rheology were determined by a control stress rheometer (Haake Rheostress 1). From the creep-recovery data it was obvious that as the amount of gelatinized fraction increased there was an increase in the elasticity of the samples. However, the samples that were produced with 75 and 100% gelatinized RS in the formulation were not smooth in texture, but lumpy. From the creep-recovery and dynamic oscillation measurements it was found that guar gum and protein mixture can be used as a stabilizer together with 50% pre-gelatinized rice semolina. This will result in an improvement in dough properties during gluten free pasta processing from rice.     

Rheological properties of gluten-free bread formulations

In this study, the rheological properties of rice bread dough containing different gums with or without emulsifiers were determined. In addition, the quality of rice breads (volume, firmness and sensory analysis) was evaluated. Different gums (xanthan gum, guar gum, locust bean gum (LBG), hydroxyl propyl methyl cellulose (HPMC), pectin, xanthan–guar, and xanthan–LBG blend) and emulsifiers (Purawave^™ and DATEM) were used to find the best formulation for gluten-free breads. Rice dough and wheat dough containing no gum and emulsifier were used as control formulations. The rice dough containing different gums with or without emulsifiers at 25 °C showed shear-thinning behavior with a flow behavior index (n) ranging from 0.33–0.68 (except pectin containing samples) and consistency index (K) ranging from 2.75–61.7 Pa sⁿ. The highest elastic (G′) and loss (G″) module were obtained for rice dough samples containing xanthan gum, xanthan–guar and xanthan–LBG blend with DATEM. When Purawave^™ was used as an emulsifier, dough samples had relatively smaller consistency index and viscoelastic moduli values compared to DATEM. The viscoelastic parameters of rice dough were found to be related to bread firmness. Addition of DATEM improved bread quality in terms of specific volume and sensory values.     

十二种常见亲水胶体对馒头品质影响的研究

本文研究了12种亲水胶体不同添加量(0.2%、0.6%、1.0%)对馒头质构、比容、水分含量及持水力的影响。结果表明:适宜浓度的瓜尔豆胶,高甲氧基柑橘果胶在降低馒头硬度及咀嚼性的同时提高了馒头弹性(p<0.05),总体上有效地改善了馒头的质构特性。0.2%的瓜尔豆胶及魔芋胶,0.2%~1.0%的高甲氧基柑橘果胶、阿拉伯胶及乳清水解蛋白,0.6%~1.0%的低甲氧基柑橘果胶及酪蛋白钠使馒头比容显著增加(p<0.05)。在室温及-4 ℃条件下,与空白比较,除阿拉伯胶对馒头持水力无显著影响外,其他亲水胶体均能不同程度的提高显著馒头的持水力。由此可知,添加适宜浓度的瓜尔豆胶、高甲氧基柑橘果胶对馒头综合品质具有较好的改良效果。     

糙米干法和湿法微粉碎对面团及面包品质的影响

将糙米分别进行干法和湿法微粉碎,与谷朊粉以4:1比例混合,制备糙米面团和面包,研究干法和湿法微粉碎对糙米面团和面包品质的影响。结果表明,经干法和湿法微粉碎后糙米粉颗粒细度显著降低,湿法粉碎糙米粉破损淀粉含量较少。干法粉碎糙米粉面团结构致密,弹性和黏性升高,糙米面包比容降低,硬度和耐咀性增强,弹性降低。随着粉碎时间的延长,湿法粉碎糙米粉-谷朊粉面团的黏性和弹性先升高后降低,面团网络结构更加紧密,其面包的比容与黏性和弹性变化规律一致,面包耐咀性和硬度增加,弹性降低。干法粉碎15 min(微粉A),湿法粉碎40 min(微粉X)时,糙米面包的比容最大,硬度和弹性适中,面包的品质较好。