In this study,we investigated the water absorption capacity,viscosity and molecular weight of arabinoxylan (AX) in dough after xylanase treatment (0、50、100、150 mg/kg),as well as its mechanism of action on dough.We found that when xylanase was added in the range of 0-150 mg/kg,the water absorption capacity and viscosity of AX were decreased,while molecular weight was reduced after this treatment.When the dosage was 150 mg/kg,the water absorption capacity of AX was the lowest (water extractable arabinoxylan (WEAX) was 4.28 g/g,water unextractable arabinoxylan (WUAX) was 7.56 g/g),viscosity was least (WEAX was 35 mL/g,WUAX was 4 035 mL/g),relative molecular weight was minimum (WEAX was 360 298,WUAX was 1 002 309).The addition of xylanase reduced water absorption capacity,shortened dough development and stability times,increased weakening degree,reduced resistance to extension and enhanced extensibility,consequently improving dough processability.

速冻馒头在储藏过程中口感和品质均会下降,需加入合适的添加剂改善其品质.通过木聚糖酶对不同冻藏时间馒头的比容、色泽、淀粉糊化度等指标研究,评价了木聚糖酶添加量对速冻馒头品质的影响.结果表明,随着冻藏时间的延长,速冻馒头的比容下降,而木聚糖酶的加入使速冻馒头的比容、色泽、淀粉糊化度和面筋的持水率明显增加,表明木聚糖酶对馒头品质的改善具有良好的促进作用.水分迁移试验表明,木聚糖酶能将更多的结合水固定在大分子物质上,阻止自由水的流失,改善水分分配状态,提高馒头的品质.木聚糖酶可作为速冻馒头良好的品质改良剂.

主要研究在不同发酵时间的条件下,一次发酵工艺对冷冻面团,馒头品质指标的影响,探讨馒头品尝评分与物性仪的TPA测试指标之间的关系,以及TPA测试在评价馒头加工品质中的应用.研究结果表明:最佳的发酵时间为15 min,在此条件下冷冻面团品质良好,馒头总评分最高.

通过对不同冻藏时间下馒头品质和淀粉回生进行研究,探讨了木聚糖酶对冷冻馒头品质及抗老化作用的影响.结果表明,添加了木聚糖酶的馒头样品在冻藏期间的感官得分、弹性、水浸提物含量均高于对熙组.冻藏48 h内,随着木聚糖酶添加量的增加,馒头的感官得分、冷冻面团水分含量呈现出先上升后下降的趋势;馒头老化速率相对较快,但随着时间的延长,老化现象减弱,基本趋于稳定.木聚糖酶可作为延缓冷冻馒头老化的有效添加剂.

研究不同添加量的木聚糖酶对面粉粉质拉伸特性、面团流变学特性和热力学特性的影响,结果表明:随着木聚糖酶含量的增加,面粉的吸水率、形成时间、稳定时间降低.随着木聚糖酶的加入,面团的延展性显著提高,但抗拉伸阻力显著下降.在频率变化过程中,木聚糖酶可使面团的弹性模量和黏性模量降低,损耗正切角tanδ增大.随着温度上升,面团的弹性模量先降低再显著升高,而tanδ不断下降.热力学分析表明,木聚糖酶使面筋蛋白强度和耐操作性均下降.

The impact of Vc on frozen dough, steamed bread quality were studied in this paper.The results showed that:with different addition of VC, the quality of frozen dough and steamed bread, coherency, etasticity viscidity and recoverability changed with. The optimal dosage of VC was 0.1%, under this condition, frozen dough have properties which could make steamed bread have better sensory quality.

The study focused on the effect of four emulsifier ssl-csl, three monoesters, the single glyceride, the sugar ester for the quality of frozen dough steamed bread. We found the best percentage of additives through a single factor experiment and orthogonal experiment The results showed that: the best formula was 0.2% ssl-csl, 0.25% three monoesters, 0.25% single glycerides, 0.5% sucrose ester. This compound emulsifier can improve the toughness of steamed bread, all indications were ideal.

Aiming to improve the quality of the frozen steamed bread dough,the key process parameters such as the amount of water,yeast and thawing time for frozen dough were studied.The technology had great effect on the sensory and texture quality including specific volume,expansion ratio,hardness and chewiness.The results indicated the addition of yeast was 1.0%,water was 50mL,using one time fermentation and mixing dough in 5min.Then dough was frozen for 35min at-40℃,and stored in a refrigerator at-20℃ for 7 days.The thawing time was 60min,when the humidity was at 75% and the temperature was at 30℃.In this case,steamed bread was attained with the best texture and sensory quality.

To improve the quality of frozen dough,the effects of fermentation time and additives on the quality of twice-fermented frozen dough were studied by measuring the texture quality and using orthogonal experimentation.The results indicated that the best fermentation time for twice-fermented frozen dough was 20min.Adding 0.40% single fatty acid glycerine ester,0.32%Vitamin C,and 0.125% CMC-Na improved the quality of frozen dough remarkably.

Using texture analyzer,the extension characteristics of frozen dough were studied through adding calcium stearoyl lactylate(CSL),sodium stearoyl lactylate(SSL),glycerin monostearate,soya lecithin,diacetyl tartaric acid esters of mono and diglycerides(DATEM).Four emulsifiers,which had evident effect on extension characteristics of frozen dough through single-factor test,were decided to do response surface analysis.The results showed that extension area was the greatest when frozen dough was added 0.11 % SSL,0.62 % glycerin monostearate,0.27 % soybean lecithin and 0.28 % DATEM,and it was evident to improve the quality of frozen dough.

the effects of xanthan gum,carrageeenen and carboxymethylcellulose sodium(CMC)on quality of frozen flour dough steamed bread was studied and discussed in this paper.By single factor test and orthogonal experiment,all indexes of quality of frozen flour dough steamed bread were evaluated.The results showed that when the optimum additive amount of xanthan gum,carrageeenen and CMC was 0.4%,0.04% and 0.08% respectively,the index scores of the internal and external structure of the finished bread were highest.The compound food gum with 0.5% xanthan gum,0.04% carrageeenen and 0.08% CMC can increase the indexes of steamed bread,such as specific volume,toughness and the internal structures,and improve the comprehensive quality of steamed bread.

The effect of proofing process on the quality of frozen dough was studied,because the gluten network of frozen dough was destroyed during freezing process,which had a negative impact on frozen dough and the quality of end product.Main factors included the amount of yeast,proofing time,freezing time and thawing time,etc.By measuring the ratio of height to diameter,cracking level,shrunken grade of dough and the aspect ratio,specific volume,quality ratings of steamed bread and other indicators,the effect of proofing process on frozen dough and the quality of steamed bread was analyzed.The optimal results were as follows: the content of yeast of 0.8%,proofing time of 7 min,freezing time of 4 d and thawing time of 45 min.

The study focuses on the influences of the level of addition, hardness and pH value of the water on the quality the steamed bread with frozen dough. All indicators of steamed bread are evaluated through the single factor experiment and orthogonal experiment, and the results show that all indicators of the steamed bread are best while adding water with pH value at 5, level of addition at 45ml/100g and hardness at 100mg/L. The best compositional formulation for specific volume is the water with pH value at 6, level of addition at 45ml/100g and hardness at 50mg/L; the best compositional formulation for color is the water with pH value at 6, level of addition at 44ml/100g and hardness at 100mg/L; the best compound scheme for surface structure is the water with pH value at 6, level of addition at 44ml/100g and hardness at 100mg/L, and the best compositional formulation for softness is the water with pH value at 5, level of addition at 45ml/100g and hardness at 100mg/L.

This article mainly researched quality of the later-fermented frozen dough,under constant temperature and humidity conditions,the effect of fermentation time and additives on the quality of frozen dough were studied. The results indicated that the best fermentation time for later-fermented frozen dough was 25 min. Adding 0.37% single fatty acid glycerine ester,0.08%Vc,and 0.08% Cryoprotectants improved the quality of frozen dough remarkably.

In order to improve the quality of the fermented frozen dough, the effects of food additives such as CMC-Na, SSL - CSL, Transglutaminase, Vc and trehalose on the quality of fermented frozen dough of steamed bread including sensory quality and texture quality were studied. The orthogonal experiment was done on the basis of single factor experiment, then the experiment data were analyzed by the fuzzy mathematical analysis. The results indicated that the inference degree of the five food additives to the quality of the steamed bread frozen dough were as follows: trehalose > CMC-Na > Vc > TG > SSL-CSL. The sensory quality and texture quality of the steamed bread frozen dough were improved when we added 0.80% CMC-Na, 0.15% SSL-CSL, 0.011% TG, 0.007% Vc and 2% trehalose in the flour.

以改良冷冻面团馒头品质为目的,研究了黄原胶、卡拉胶、瓜尔豆胶对冷冻面团馒头的比容、扩展比影响,并进行了感官评价。通过单因素试验,确定黄原胶、卡拉胶、瓜尔豆胶的相对最佳添加量分别为0.06%、0.45%、0.35%。在此基础上,进行正交试验,利用极差分析,确定了增稠剂复配的最佳比例为:黄原胶0.06%、卡拉胶0.45%、瓜尔豆胶0.35%。

As special and high-gluten flour of frozen dough for study,this paper studied the quality impact of effects of thickening agent on frozen dough tensile properties,wet gluten content,water loss rate and colour through adding xanthan gum,guar gum,carrageenan,sodium polyacrylate.Results showed: for special flour,xanthan gum(0.3%),guar gum(0.8%),carrageenan(0.6%),sodium polyacrylate(0.05%) added,extension area and wet gluten content is highest levels;for high-gluten flour,xanthan gum(0.2%),guar gum(1.2%),carrageenan(0.6%),sodium polyacrylate(0.05%) added,extension area and wet gluten content is the highest;frozen dough by adding thickener,water loss rate has decreased,but regularity is not strong;as increase of the amount of the xanthan gum,guar gum,sodium polyacrylate added,L value is increased,dough brightness increased,but with increase in amount of carrageenan added L value decreases,dough brightness diminished.

Using texture analyzer,this paper studied stretching properties of frozen dough through adding xanthan gum,guar gum, carrageenan, sodium polyacrylate thickening agent. Through the single-factor test, the four thickening agent were definited to do response surface analysis. The results showed that: when adding xanthan gum 0.33% , guar gum 0.90%, carrageenan 0.61%,the Sodium polyacrylate 0.05%,the greatest stretching area of frozen dough was obtained,it was helpful to improve the quality of frozen dough (special grade No.1 flour) .

We carried out single factor experiments to investigate the effects of xanthan gum,carrageenan and sodium carboxymethylcellulose on the quality of frozen dough Mantou and to determine their optimal addition amounts in flour.Based on the single factor experiments,we also conducted orthogonal experiments to study the effects of xanthan gum,carrageenan and sodium carboxymethylcellulose on the quality of frozen dough Mantou so as to determine the optimal ratio of the compound food gum.The results show that the optimal formulation of the compound food gum is as follows: xanthan gum 0.04%,carrageenan 0.5%,and CMC 0.08%;and compound food gum with the optimal formulation can greatly improve the comprehensive quality of the frozen dough.

本文研究了不同发酵时间、不同冷藏时间条件下冷冻面团的裂纹情况、冻缩情况、成品高径比、比容、质构及口感等品质指标的变化。结果表明:随着发酵时间的增加,面团裂纹情况、皱缩情况呈增加趋势,高径比呈减小趋势,综合各个品质指标,确定了最佳发酵时间为10min;随着冷藏时间的增加,在短期内面团品质及成品品质所受的影响较小,但是随冷藏时间的继续增加,成品的色度和比容会明显下降,最后综合各品质指标确定冷藏时间不宜超过8天。