Effect of Waxy Wheat Flour Blends on the Quality of Chinese Steamed Bread

Steamed bread is very popular in the East and Southeast Asian regions, and its quality is affected by some physicochemical properties. Chinese steamed bread was made by adding waxy flour into normal wheat flour in the present study. The results showed that specific volume was not affected by the proportions of waxy flour, whereas, adding waxy flour decreased the appearance, color, texture, elasticity, stickiness, and the total score of Chinese steamed bread. However, there were no significant differences in all values when the proportions of waxy flour were below 10%. All evaluations but specific volume of Chinese steamed bread were positively influenced by the peak viscosity, resistance, and maximum resistance. When the waxy flour proportions were below 25%, the firmness of Chinese steamed bread stored at -18℃ for 3 days gradually decreased with the increase of waxy flour. It was revealed that the qualities of Chinese steamed bread cannot be improved by waxy flour but it can be widely used in frozen storing food in the future.

Effects of Sourdough Addition on the Quality and Shelf Life of Chinese Steamed Bread

The effect of adding sourdough with lactic acid bacteria(Lactobacillus plantarum M616) on dough quality and the sensory scores, specific volume, crumb firmness, and spread ratio of resultant Chinese steamed bread were studied. The moisture content of crumb and texture characteristics of the Chinese steamed bread with sourdough during storage were analyzed. In this study, 10%,20%, 30%, and 40% of sourdough addition was investigated. The sourdough starter resulted in significant decrease in the water absorption, development time, stability, and farinograph quality number of the dough. The addition of sourdough improved the quality of Chinese steamed bread such as improving the sensory scores and specific volume, decreasing the crumb firmness, and a lower spread ratio was observed with an increase in the sourdough concentration up to 30%. Sourdough addition delayed a fast decrease in the moisture content of the Chinese steamed bread crumb during storage. The texture profile analysis of the bread crumb indicated that the addition of sourdough improved the quality and delayed the staling speed of Chinese steamed bread during storage.Moreover, inclusion of 30% sourdough produced the best protective effect on product staling.

Effect of Pectins on Dough Rheology and Chinese Steamed Bread Quality

Dough preparation and performance are two critical factors influencing the final quality of wheat products. The influence of high and low methoxyl pectins on empirical and dynamic rheological properties of dough and Chinese steamed bread(CSB)quality were investigated. Different concentrations of high methoxyl apple pectin(HMAP), low methoxyl apple pectin(LMAP),and amidation apple pectin(ALMAP) were tested. Results from dynamic and empirical rheological tests indicated that all concentrations of pectins tested(0.2%, 0.6%, and 1%) negatively affected the gluten network. The low methoxyl pectins, LMAP and ALMAP, which had higher anionic densities, resulted in a pronounced weakening of the dough. Meanwhile, dough fermentation properties improved in the presence of appropriate pectins concentrations, and higher maximum dough height, stability of dough pore space, and gas retention were recorded. HMAP was the pectin most effective in influencing dough fermentation properties at all tested concentrations. Regarding CSB quality, textural properties, specific volume, moisture content, and water-holding capacity were analyzed. Generally, the textural properties of CSB were improved, including improved springiness and decreased hardness and chewiness, when 0.2%–0.6% HMAP or LMAP was used. The specific volume of CSB was increased by adding 0.2%–1% HMAP,0.6%–1% LMAP, or 0.2%–0.6% ALMAP. Moreover, CSB moisture loss was progressively reduced in the presence of different pectins at all tested concentrations during storage. In conclusion, pectins, especially HMAP, are good additives for improving the fermentation properties of dough and overall quality of CSB.

Relationship between physicochemical characteristics of Korean wheat flour and quality attributes of steamed bread

The purpose of this study is to identify major factors affecting the manufacture and quality of steamed bread,consumed in Southeast Asia including China,Japan,and Korea.Hence,flours of 11 Korean wheat cultivars were used to evaluate quality attributes of two different styles of steamed bread,Korean style steamed bread(KSSB)and northern-style Chinese steamed bread(NSCSB).KSSB prepared more ingredients and higher optimum water absorption of dough than NSCSB because Korean consumers prefer white and glossy surface and soft crumb.KSSB showed lower height,larger diameter and volume of steamed bread,higher stress relaxation,and softer texture of crumb than NSCSB.The correlation between flour characteristics and quality of steamed bread was different in KSSB and NSCSB.About 90%of variability in the height and volume of KSSB could be predicted from protein content,mixing tolerance of Mixograph,average particle size of flour,final viscosity and solvent retention capacity.Protein content and quality parameters also could explain the variation of steamed bread height in NSCSB.Korean wheat carrying Glu-A3c allele produced higher volume of steamed bread(704.7 mL)than Glu-A3d allele(645.8 mL)in KSSB,although there was no significant difference in volume of NSCSB by glutenin compositions.Glu-D1d and Glu-A3c alleles had softer texture of crumb than Glu-D1f and Glu-A3d alleles in KSSB,Glu-B3i allele also showed lower hardness of crumb than their counterpart allele in NSCSB.Hard wheat showed higher height and volume of steamed bread,and lower stress relaxation and hardness of crumb than soft wheat in KSSB.

Study on Quality Traits for Steamed Bread Made from 25 Representative Wheat Varieties in Shandong Province

In order to study steamed bread quality traits and explore good wheat cultivars, 25 wheat cultivars grown in Shandong province were used through one-process fermentation procedure to examine the variability of steamed bread quality traits and the correlation between quality and score. The results showed that all the steamed bread quality traits expressed large variable coefficient except volume, L* value, l* value and cohesiveness traits, which suggested that the genetic diversity made from wheat in Shandong province was large. The average comprehensive score of the steamed bread was 76.8 for the tested 25 varieties, and ten varieties reached the good steamed bread level, which were Liangxing 99, Luyuan 205, Jimai 22, Jinan 17, Tainong 19, Wennong 17, Huaiyin 84137, and Huaimai 8. The main quality factors affecting the steamed bread score were volume, L* value, A* value, hardness, chewiness, and adhesiveness. Among these factors, the adhesiveness has a significantly positive correlation with the hardness and cohesive, and the volume has a significantly positive correlation with the A* value. The volume, L* value has a significantly positive correlation with score, A* value, hardness and chewiness, and gumminess has a significantly negative correlation with the score. There was no correlation between the score and other traits. The results will benefit the understanding of steamed bread quality in wheat cultivated in Shandong. l

Effects of acetic acid bacteria in starter culture on the properties of sourdough and steamed bread

Sourdough starters for making traditional steamed bread are rich in microbes.Studies have shown that,in addition to yeast and lactic acid bacteria(LAB),acetic acid bacteria(AAB)are other functional species in sourdough,but the influences of AAB on the properties of sourdough and steamed bread were rarely reported.This study aimed to assess the effects of a selected strain of acetic acid bacterium on the properties of sourdough and steamed bread.Sourdoughs and steamed breads were prepared from five different starter cultures,marked as CK(control check,with no starters),Y(only yeast),YL(yeast+LAB),YA(yeast+AAB)and YLA(yeast+LAB+AAB),and their properties were determined.The results of sour dough properties showed that the YLA sourdough had the highest total titratable acid of 14.6 mL and the lowest pH of 3.87 compared with the other groups after fermentation to 8 h;and the YLA sourdough had the greatest elasticity and viscosity.The results of quality properties of steamed bread revealed that the L*value(88.40±0.09)of the YA steamed bread was significantly higher than those of the YLA and YL steamed breads;the YLA steamed bread had the highest specific volume and the highest sensory score of 89.6±3.31 in comparison to those of the other groups;the hardness and chewiness of YLA and YA steamed breads were significantly lower than those of the other groups.Volatile compounds in the steamed breads were also determined by SPME-GC-MS.A total of 42 flavor substances were detected,including 3 kinds of alcohols,8 kinds of aldehydes,7 kinds of ketones,2 kinds of acids,15 kinds of esters,1 furan,and 6 kinds of other types of compounds,mainly alkanes and esters,followed by alcohols and aldehydes.The YLA steamed bread was richer in esters,aldehydes,and acids than those from the other treatment groups.By contrast,alkanes and aldehydes were dominant in the Y and YL steamed breads.Therefore,the flavor and quality of the steamed bread made from the YLA sourdough could be improved obviously.These results could provide references for the application of AAB in dough fermentation and the improvement of new kinds of starters.

Study on the Quality Evaluation of Steamed Bread and the Physical and Chemical Properties of Wheat

In this study,the different physical and chemical properties of wheat were studied,and on this basis,and the quality of steamed bread made was evaluated.We analyzed the correlation between the evaluation indexes of steamed bread and the basic physical and chemical indexes of wheat,and investigated important factors that affect the evaluation indexes of steamed bread,including flour extraction rate,protein content,amylose content,protein,added amount of yeast,fermentation time and other aspects.According to the study results,it was shown that different factors had different effect on steamed bread quality,with both positive correlation and negative correlation.

不同分子量蛋白质对小麦品质及馒头加工品质的影响

为了解不同分子量蛋白质对小麦品质及馒头加工品质的影响,以石优17、石4366、石麦15等30个石麦系列小麦品种为材料,对不同分子量蛋白质相对含量、品质特性以及馒头加工品质进行了检测与分析。结果表明,UPP(SDS不溶性蛋白大聚体)、LPP(大分子量聚合体蛋白)、LMP(大分子量单体蛋白)的相对含量及LPP/LMP比值与小麦粉的大多数品质指标存在显著或极显著相关性;不同分子量蛋白质相对含量较蛋白质含量更能反映小麦品质;UPP相对含量可作为小麦粉品质性状及面筋特性的预测和评价指标。蛋白质含量显著影响馒头的粘着性,UPP、LPP、LMP相对含量及LPP/LMP比值主要影响馒头质构特性中的硬度、胶着性及咀嚼度。UPP相对含量可以作为评估小麦粉是否适宜馒头加工的重要指标。

基于模糊数学优化银条小米杂粮馒头工艺及体外消化特性分析

为改善我国居民的膳食结构,研制一款品质良好、低淀粉水解指数(Hydrolysis index,HI)和低血糖生成指数(Glycemic index,GI)的银条小米杂粮馒头,以杂粮馒头的外形色泽、组织结构、成品口感及成品风味为评价指标,建立模糊数学感官分析模型,通过单因素试验、质构特性分析及正交试验优化其加工工艺。最终确定银条小米杂粮馒头最佳配制比如下:以小麦粉和小米粉总量(100%)为基准,小米粉添加量35%,银条添加量20%,水添加量40%,酵母添加量1.1%,此条件下的杂粮馒头HI值为58.47,GI值为69.76,微生物及理化指标均符合国家标准。

预醒发冷冻生胚馒头熟制工艺优化

为提高冷冻生胚馒头的品质,该文探究预醒发时间、解冻方式和蒸制方式对馒头比容、感官评分和质构特性的影响,结合单因素和Box-Behnken响应面法,优化预醒发冷冻生胚馒头熟制工艺。通过差示扫描量热仪、扫描电子显微镜和面包图像分析仪,分析对照生胚面团与最优工艺条件下预醒发冷冻生胚馒头面团可冻结水含量、微观结构以及馒头孔隙分布的变化。结果表明,最佳预醒发冷冻生胚馒头熟制工艺为预醒发时间22 min,醒发箱解冻时间58 min,蒸箱蒸制时间18 min,该条件下馒头具有最优的感官品质,且不发生起泡收缩现象,馒头品质得到明显改善。

不同包装形式对大米-小麦混合粉馒头贮藏品质的影响

为探究大米-小麦混合粉馒头的最佳包装形式和贮藏方式,通过分析馒头中微生物含量、水分含量、质构特性及复蒸后感官特性,揭示透气包装、脱氧包装和密封包装在25℃和4℃贮藏条件下对大米-小麦混合粉馒头品质的影响。研究发现,透气包装馒头的水分含量、弹性的下降速率和硬度的上升速率最快,感官评分最低;整个贮藏中脱氧包装馒头的水分含量和硬度略小于密封包装馒头,弹性大于密封包装馒头。在25℃贮藏时透气包装、脱氧包装和密封包装馒头分别在1、6、3 d时菌落总数超过6 lg CFU/g;2、5、4 d时霉菌数超过标准GB/T 21118-2007200 CFU/g,1、3、5 d时出现感观品质劣变。在4℃贮藏时密封包装、脱氧包装和透气包装馒头分别在8、14、12 d时菌落总数超过6 lg CFU/g,10、12、10 d时霉菌数超过标准GB/T 21118-2007200 CFU/g,8、12、10 d时出现感观品质劣变。因此,采用脱氧包装的低温贮藏形式使馒头具有较好的贮藏品质。

2种乳酸菌发酵酸面团对馒头品质与风味的影响

选取融合魏斯氏菌、植物乳酸杆菌2种乳酸菌分别与酵母发酵以及共同与酵母发酵(LP+WC)制备酸面团,与仅添加酵母的酸面团(CK)对比,研究不同酸面团的乳酸菌菌落数变化、有机酸含量及其对馒头面团水分分布、流变学特性以及馒头品质和风味的影响。结果表明,添加乳酸菌发酵的酸面团24 h后pH值保持稳定,WC+LP组乳酸菌菌落数在24 h达到最高,为9.34 lg(CFU/g酸面团)。发酵24 h后,LP组乳酸含量最多,为7.75 mg/g酸面团;LP+WC组乙酸含量最多,为0.49 mg/g酸面团。添加酸面团的馒头面团T2弛豫时间为235.43 ms,CK组为252.35 ms,低于未添加酸面团的馒头面团的T2弛豫时间289.94 ms,且使馒头面团黏弹性下降。酸面团的加入增加了馒头的比容,LP+WC组比容最大为2.17 mL/g,较普通干酵母面包(OSB)增长了20.56%,降低了馒头的硬度,LP+WC组的硬度较OSB降低了25.89%,提升了馒头的弹性,LP+WC组弹性较普通干酵母面包(OSB)增长了4.5%。GC-MS分析表明,在LP+WC组中检出35种风味物质,种类最多,表明融合魏斯氏菌和植物乳酸杆菌复合发酵酸面团对馒头品质及风味有改善作用。

改性豆渣的工艺优化及豆渣馒头的品质改良

为加快大豆副产物豆渣的加工利用效率,该文在单因素试验基础上,利用响应面试验进行优化,确定豆渣的最佳改性工艺,同时通过质构、色差和血糖生成指数等确定改性豆渣在馒头中的最适添加量。结果表明,豆渣的最佳改性条件为复合酶添加量0.6%、改性时间6 h、接菌量6%,改性豆渣在馒头中的最适添加量为30%,所制得的馒头颜色微黄、硬度适中、香气浓郁,富含膳食纤维,预测血糖生成指数(predicted glycemic index,pGI)为58.35±1.29。

不同粒度小麦重组粉对馒头品质的影响

使用验粉筛将市售小麦粉筛分为105~137、95~105、88~95、58~88、<58μm 5个不同粒度,研究不同粒度小麦粉的粒度分布、颗粒形态,不同粒度重组粉的理化指标、粉质特性及其馒头的比体积、宽高比和质构特性。结果表明:随着粒度的减小,小麦粉的D_(10)、D_(50)、和D_(90)显著减小,淀粉、破损淀粉含量增加,蛋白质和湿面筋含量先增大后减小。粒度为58~88μm和58μm以下的小麦粉对重组粉的粉质特性和馒头品质影响显著,缺少58~88μm粒度的重组粉的吸水率和粉质指数最小、稳定时间最短、弱化度最大,所制馒头的比体积最小、质构特性最差、感官评分最低,缺少58μm以下粒度的重组粉则与之相反。综上所述,不同粒度小麦粉对馒头品质的贡献度不同。

干燥温度对高水分小麦加工和应用品质的影响

为探究不同干燥温度对高水分小麦品质的影响,采用不同热风干燥温度(65、85、105、125℃)对初始水质量分数26%的小麦进行干燥处理,以未烘干小麦为对照,分析干燥对小麦加工及应用品质的影响。结果表明:热风干燥温度对高水分小麦品质影响显著,随热风温度升高,干燥后的小麦容重显著下降,裂纹率显著上升。在相同条件下制得的小麦粉,出粉率和灰分含量变化不大,破损淀粉有所下降,白度上升,粒径减小,溶剂保持力、沉淀指数降低,其中125℃下出粉率影响较大,破损淀粉含量和白度影响较小。与对照样品相比,65、85℃干燥对面筋含量和质量影响不大,面团的加工特性有所改善,馒头比容变化不大,硬度、黏性显著降低。当干燥温度为105℃和125℃时,湿面筋含量、形成时间、稳定时间显著下降,面团的操作性能降低,馒头比容和感官得分下降。对于制作馒头而言,26%水质量分数的小麦可采用不高于85℃的干燥温度。

粗糙脉孢菌发酵改性黑小麦麸皮馒头配方优化及其品质分析

以黑小麦粉、粗糙脉孢菌(Nc)发酵改性黑小麦麸皮(BWB)为主要原料,制备Nc-BWB馒头。以馒头感官评分、比体积及宽高比为综合评价指标,通过单因素试验和响应面试验优化馒头配方,并对其色度、质构和挥发性风味物质进行分析。结果表明:最佳配方为以Nc-BWB与黑小麦粉总质量计,Nc-BWB添加量8%、水添加量49%、酵母添加量1%,在此条件下制得的Nc-BWB馒头综合评分为87.25。与BWB馒头和纯黑小麦粉馒头相比,Nc-BWB馒头L^(*)值最低,a^(*)值最高。Nc-BWB馒头中醇类、萜烯类、杂环类挥发性物质相对含量最多;四氢薰衣草醇、苯乙醛、反式-2,4-癸二烯醛、丙位壬内酯、亚油酸乙酯、α-石竹烯是Nc-BWB馒头中独有的风味物质。质构分析表明,用Nc发酵改性后的BWB制备馒头对其品质起到了改善作用。

安徽麦区软质小麦籽粒品质和终端制品品质评价

为明确安徽大田生产环境下软质小麦籽粒和终端产品品质表现,评价优质软麦品种的加工适用性,本研究选取该区当前推广种植的24个软质小麦品种,对其籽粒和面粉的主要品质性状及其制品南方馒头和曲奇饼干的品质进行差异性、相关性分析,并以美国软白麦近五年的主要品质性状平均值为理想指标进行灰色关联度比较。结果表明,供试材料的硬度、面粉色泽b^(*)、湿面筋含量、面团形成时间、稳定时间等籽粒品质性状变异系数较大,而容重、面粉L^(*)值和吸水率变异系数较小。南方馒头品质性状中,白度差异最小,比容差异最大;曲奇饼干品质性状中,感官评分变异系数较大,饼干直径均值和变异系数都较小。蛋白质含量、湿面筋含量、稳定时间均符合弱筋标准(GB/T 17320-2013)的样品数为0。相关分析表明,容重、降落值、面粉L^(*)、b^(*)、白度与大部分性状间相关性不显著;籽粒硬度与水SRC和乳酸SRC均呈显著正相关,与湿面筋含量和面粉a^(*)值均呈显著负相关。蛋白质含量与面粉a^(*)值等7个指标均呈显著正相关,与面粉b^(*)、碳酸钠SRC和面团稳定时间均呈显著负相关;4种溶剂保持力均与吸水率均呈显著正相关;面筋性能指数GPI与蛋白质含量等6个性状均呈显著正相关。南方馒头比容与籽粒硬度、面团形成时间和稳定时间均呈显著负相关,与蛋白质含量、湿面筋含量和面粉a^(*)值均呈显著正相关性;曲奇饼干直径、直/厚比与湿面筋含量、水SRC间均呈显著负相关。灰色关联度结果显示,紫麦19、百农201、豫麦158、隆平麦968、荃麦725共5个品种与美国软白麦关联度均超过0.900,其总体品质表现与美国软白麦较接近,是较好的饼干和南方馒头小麦品种。

小麦淀粉对面团微观结构及冷冻面团馒头品质的影响

淀粉作为小麦粉的主要成分在决定面团特性以及冷冻面团馒头品质中发挥着重要的作用。采用分离重组的方法,探究淀粉添加比例分别为0%(对照组)、10%、15%、20%、25%、30%、35%、40%、45%、50%时,混合粉糊化特性、面团微观结构、游离巯基含量和冷冻面团馒头品质的变化。结果表明:不同比例淀粉的添加量改变了混合粉的糊化特性和粉质特性,分别与淀粉添加比例呈线性相关关系。随着淀粉添加比例的增加,混合粉面团弱化度和面团中游离巯基含量逐渐增加,从微观结构的变化发现面团中面筋蛋白网络的连续性逐渐降低。当淀粉添加比例达到20%时,冷冻面团馒头的硬度和咀嚼性达到最小值,分别为2833 g和2567 g。适当增加小麦粉中的淀粉含量改善面团的加工适应性,更利于冷冻面团馒头的制备。

秋葵多糖对冷冻面团贮藏稳定性的影响

该文探讨了秋葵多糖对在贮藏过程中面团流变学特性和馒头品质变化的影响。结果表明,秋葵多糖可使面团黏弹性增大,并能减缓面团在冷藏过程中黏弹性减小程度;降低可冻结水含量,有效抑制冷藏期间可冻结水含量的升高;适量添加秋葵多糖可改善面团的起发性,增大面团持气率和馒头比容,减缓冷冻面团馒头硬度和弹性的劣变。结果显示秋葵多糖添加量在0.5%~1.5%(质量分数),均可改善冷冻面团品质,提升其贮藏稳定性。

蛹虫草玉米馒头加工工艺及品质

以玉米粉和蛹虫草粉作为添加物制作蛹虫草玉米馒头,并对其加工工艺和品质特性进行探究。基于单因素试验,探究玉米粉添加量、蛹虫草粉添加量、酵母添加量及水添加量对蛹虫草玉米馒头品质的影响,并通过响应面试验优化其加工工艺。得到蛹虫草玉米馒头的最佳工艺条件为以中筋面粉100 g为基准,玉米粉添加量26 g、蛹虫草粉添加量8 g、酵母添加量2 g、水添加量75 g。在此工艺下制作的蛹虫草玉米馒头表面完整光滑,结构均匀,爽口不粘牙,风味清香,感官评分为89.35±0.23。对其理化指标进行测定,均符合国家标准。优化后的蛹虫草玉米馒头与普通小麦馒头相比,在质构特性和理化指标方面无显著性差异,风味更为独特,营养价值更高。