酶制剂及溴酸钾对面团流变学性质及显微结构的影响

本文研究了葡萄糖氧化酶、戊聚糖酶、脂肪酶和溴酸钾单独使用及复合使用时对面团流变学性质及面团内部显微结构的影响，分析了面团流变学性质和显微结构间的内在联系。同时，对在小麦粉品质改良中以酶制剂替代溴酸钾的可行性进行了简要讨论。     

葡萄糖氧化酶对全麦面团及全麦馒头品质改良的影响

将葡萄糖氧化酶(glucose oxidase,GOD)应用于全麦馒头的制作,通过测定面团的流变、热机械、吹泡特性以及全麦馒头品质的相关指标,研究该酶对全麦面团及馒头品质的影响。实验结果表明,随着GOD添加量的增加(小于300 U/kg),全麦面团的稳定时间增加,但对全麦粉吸水率没有显著改变;峰值粘度(C3)、保持粘度(C4)增加,表示面团的糊化稳定性越好,面团稳定性增加;当GOD的添加量为300 U/kg时,全麦面团的弹性模量、粘性模量最大,tanδ 值最低,全麦面团固体特性增强,机械强度增大;面团P值、L值、W值增加,改善了面团的韧劲、延展性和持气性。与空白组对照可知,随着GOD添加量的增大(小于300 U/kg),馒头的比容呈现增加趋势并且硬度、咀嚼性以及黏附显著降低,品质得到改善,但是过量的GOD(500 U/kg)反而对其品质有负面的影响。因此添加GOD 300 U/kg时,可改善面团的网络结构,改良全麦馒头的品质。     

葡萄糖氧化酶和戊聚糖酶对面团流变学性质的影响

应用粉质仪、拉伸仪和动态流变仪,研究了葡萄糖氧化酶(GOD)和戊聚糖酶(PE)对面包粉和中筋粉流变学性质的影响.结果表明,GOD增大了两种小麦粉的吸水率、形成时间和稳定时间、降低了弱化度,而PE对小麦粉粉质的作用效果与GOD相反;添加GOD后两种小麦粉的拉伸阻力和拉伸面积都增大,而PE的作用主要表现在改善了小麦粉的延伸度,拉伸阻力下降;两种酶共同使用时小麦粉的稳定时间增加,延伸性和拉伸面积增大,粉质和拉伸特性得到全面改善.在频率扫描过程中,添加GOD的两种面团弹性模量(G')和黏性模量(G')增大,损耗角正切值tan δ减小,其中GOD对中筋粉的影响大于面包粉.PE使面团的G'和G'下降,tan δ增大,而两种酶同时添加时有协同增效作用.     

复合酶制剂对全麦馒头品质的改良作用

受加工技术水平影响,我国全谷物食品感官品质欠佳,产业发展缓慢。本研究采用生物酶对以纯全麦粉制作的馒头制品进行品质改良。结果表明:葡萄糖氧化酶(Gox)、戊聚糖酶(Pn)和纤维素酶(Ce)三酶协同作用,当添加量分别为Gox 40 mg/kg、Pn 40 mg/kg、Ce 30 mg/kg时,馒头比容可达到2. 69 cm~3/g,较空白样品提高22%;馒头高径比0. 56,挺立度适中;同时馒头内部结构明显改善,气孔均匀、质地疏松、富有弹性、粗糙感显著降低。     

戊聚糖酶与氧化酶对面团流变性质影响的研究

研究了戊聚糖酶(Pentopan)、葡萄糖氧化酶(GOX)以及脂肪氧合酶(活性大豆粉,SF)对普通粉和专用粉面团流变性质的影响。由粉质曲线可知,不同品种的面粉,酶对面团吸水量的影响不同,对普通粉影响最大的是GOX;对专用粉影响最大的是Pentopan。由动态流变学试验知,Pentopan降低了面团中的弹性成分,GOX使弹性成分增加;GOX对普通粉的影响较大,SF则对专用粉的影响较大。      

戊聚糖酶与氧化酶对面团流变性质影响的研究

研究了戊聚糖酶(Pentopan)、葡萄糖氧化酶(GOX)以及脂肪氧合酶(活性大豆粉,SF)对普通粉和专用粉面团流变性质的影响。由粉质曲线可知,不同品种的面粉,酶对面团吸水量的影响不同,对普通粉影响最大的是GOX;对专用粉影响最大的是Pentopan。由动态流变学试验知,Pentopan降低了面团中的弹性成分,GOX使弹性成分增加;GOX对普通粉的影响较大,SF则对专用粉的影响较大。     

食品添加剂对全麦馒头品质的影响

研究了蒸馏单甘酯、大豆磷脂及抗坏血酸对全麦馒头品质的影响。通过单因素试验和正交试验,确定了全麦馒头制作中蒸馏单甘酯、大豆磷脂及抗坏血酸的最佳添加量。结果表明,蒸馏单甘酯、大豆磷脂和抗坏血酸均可显著改善全麦馒头品质;以试验用全麦粉为原料,当蒸馏单甘酯、大豆磷脂和抗坏血酸添加量分别为5 g/kg、3 g/kg和80 mg/kg时,所制得全麦馒头品质最好。     

全麦发酵面团菌群结构分析及对风味物质的影响

采用宏基因组学的方法解析全麦传统发酵面团细菌菌群结构组成,确定其核心菌属为乳酸菌科乳杆菌属短乳杆菌种。对全麦传统发酵面团和商业发酵面团的风味物质进行了测定,发现传统发酵面团风味物质种类比商业发酵多9种,在含量上也存在差异,但均以烃的含量最多。说明传统发酵剂更有利于全麦面团风味物质的形成,更易让消费者接受,为传统发酵剂在全麦制品中的应用提供理论支持。     

葡萄糖氧化酶和戊聚糖酶对面团流变学性质的影响

面团流变学特性是小麦品质的重要指标,是小麦粉吸水量、面团耐揉性和粘弹性的综合表现。应用粉质仪、拉伸仪和动态流变仪,研究了葡萄糖氧化酶（GOD）和戊聚糖酶（PE）对面包粉和中筋粉流变学性质的影响。结果表明,GOD增大了两种小麦粉的吸水率、形成时间和稳定时间、降低了弱化度,两种小麦粉的拉伸阻力和拉伸面积都增大,提高了面团的抗拉阻力,使面包粉的各项指标更加符合面包制作的要求。而PE对小麦粉粉质的作用效果与GOD相反,     

麸皮预处理对全麦面团及面包的影响

本实验分别采用微波、烘烤、常压蒸汽、高压蒸汽对小麦麸皮进行预处理,研究比较了不同预处理方法对全麦面团和面包品质的影响。结果表明：和未处理全麦粉相比,烘烤、常压蒸汽和高压蒸汽处理均使全麦粉的稳定时间提高,其中常压蒸汽效果最显著,提高了4.2 min;同时,这三种处理方式分别使全麦面包的比容增加了6.92%、9.34%、5.19%,硬度分别降低11.81%、21.79%、19.57%,弹性分别提高2.59%、3.06%、1.65%。推测原因是这三种处理方式均显著降低了麸皮中的还原型谷胱甘肽含量,使全麦面团的游离巯基显著减少,二硫键显著增加,其中常压蒸汽和高压蒸汽效果最显著,分别使还原型谷胱甘肽减少了66.77%、69.30%,使游离巯基减少了40.43%、42.77%,使二硫键增加了51.35%、38.63%。综上,采用烘烤、常压蒸汽、高压蒸汽对麸皮预处理,可以通过降低还原型谷胱甘肽含量、提高二硫键含量来提高面团的稳定性,进而改善面包品质,且常压蒸汽处理的改善效果最好。     

The influence of xylanase and thermal treatment on the composition and interfacial rheology properties of whole wheat dough liquor

The dough liquor (DL) centrifuged from dough played an important role in determining the gas cell stability during dough making, and the adding of xylanase (XYL) in the dough could efficiently increase the stability of DL foam, especially at 60 °C. In this work, we prepared whole wheat dough added with different dosages of XYL and extract the DL. The components especially proteins in DL and their interaction mechanism and interfacial rheology properties at the air–water interface were studied. The proteins formed protein aggregates (>150 kDa) at 60 °C. After XYL treatment, DL solution exhibited higher protein surface hydrophobicity and surface pressure. And the equilibrium surface pressure of DL varied between 23 and 28 mN m⁻¹. At 25 °C, the interfacial dilatational modulus increased by 26.77% and 14.22% compared with control, respectively. And the XYL can improve the interface shear strength both for the unheated and heated DL solutions. These findings showed that XYL might improve the ability of DL constituents to stabilise the air–water interface to contribute to the stability of gas cells in the dough. The obtained results have provided a theoretical basis for improving the gas cell stability by changing the properties of whole wheat DL with the addition of XYL.     

细度对挤压麦麸理化特性及其全麦粉加工品质特性的影响

以挤压麦麸(粗麸、细麸、胚芽、次粉混合料)为原料,研究筛分细度(粒径44.15~198.48μm)对挤压麦麸的理化特性及其全麦粉加工品质特性的影响。结果表明:随着筛分目数的增加,挤压麦麸的粒径范围分布变窄;筛分细度对其戊聚糖、阿魏酸含量的影响较大;对其持水性、溶胀性的影响较小,对全麦粉的糊化特性、粉质特性的影响较小;挤压处理麦麸混合料可获得较均一的麦麸产品。     

Effect of inulin on rheological properties of soft and strong wheat dough

The influence of inulin with different degrees of polymerisation (DP) on the farinograph characteristics, extensograph parameters and fermentation rheological properties of soft and strong wheat dough was explored. The results showed that the addition of inulin can reduce the water absorption of doughs, and inulin with lower DP had more significant effect and the influence on the soft dough was stronger than the strong dough. Inulin can enhance mechanical properties of the gluten network and improve the resistance to mixing of soft dough. The extensibility of doughs decreased with increasing inulin. Inulin increased the resistance to extension of soft dough; however, it is reverse for strong dough. Adding inulin significantly increased the volume of gas production and the maximum expansion height of doughs, and the effect of inulin with lower DP was more prominent. Additionally, the gas‐holding capacity of doughs was enhanced by inulin.     

Effects of aleurone-rich fraction on the hydration and rheological properties attributes of wheat dough

This study aimed to evaluate the effects of incorporation of aleurone-rich fraction (ALF) on the hydration and rheological properties of wheat dough. Incorporation of ALF significantly increased water absorption (P < 0.05) and competition for water in dough was observed. Peak viscosity, through viscosity, and final viscosity decreased with the amount of ALF added (P < 0.05), whereas 20% ALF had stronger gel ability than whole-wheat flour. Dynamic rheological experiments revealed ALF blend dough were more stable than whole-wheat dough, which was in accord with the higher dough stability and strength observed in Mixolab. Scanning electron microscopy showed that disruption of gluten network with ALF incorporation, whereas 20% ALF showed better stability dough structure than the whole-wheat dough. Considering those influences on dough properties, the 20% ALF seems to be a promising substitute for whole-wheat flour to producing dietary fibre-rich products.     

藜麦-小麦混合粉面团特性及藜麦馒头加工工艺

探讨不同比例的藜麦全粉对高筋小麦粉面团流变学特性的影响,确定藜麦全粉馒头中最佳的藜麦全粉添加比例并进行馒头加工工艺的优化。通过混合实验仪和吹泡仪对面团流变学特性进行测定,以馒头的感官评价和质构特性为评价指标,对藜麦全粉馒头的酵母添加量、发酵时间和醒发时间进行优化。结果表明：藜麦全粉馒头的最佳藜麦全粉添加量为15%;当酵母添加量0.75%、发酵时间100 min、醒发时间15 min时,藜麦全粉馒头的感官评价总分达到最高值86.58,比容达到最高值3.02 mL/g,同时,硬度、咀嚼性和胶着性分别达到最低值9.76、45.53 N和6.66 N。     

维生素C对面团特性影响研究

通过研究Vc对面团特性影响表明,面粉中添加Vc能增加面团吸水率和形成时间,降低面团弱化度,增加面团拉伸面积、拉伸阻力和拉伸比值,降低面团延伸性;其最适添加范围为120～160ppm.     

不同酵母对面团发酵特性及馒头品质的影响

就不同酵母对面团发酵特性和馒头品质的影响进行了试验.通过比较不同酵母发酵面团的产气量和面团膨发状态,进而确定相同条件38℃,88%RH,酵母添加量0.8%,不同酵母的最适发酵时间,然后对其发酵的馒头进行感官评价和质构测定,结果显示:不同酵母发酵面团时的产气量和面团膨发状态不同,Y-1、Y-2、Y-3和Y-4的最适发酵时间依次为40、30、25和30 min.由感官评价和质构测定结果还得出结论:不同酵母显著影响馒头产品的感官评价总分,且感官评价和质构测定参数与其面团发酵性能相一致.