发酵时间和蒸制强度对预拌粉马拉糕面糊特性及品质的影响

Effects of Fermentation Time and Steaming Intensity on the Batter Characteristics and the Quality of Mala Cake Made Using Pre-mixed Powder

马拉糕的传统制作步骤复杂耗时,产量低且品质不稳定,而采用预拌粉制备马拉糕能有效缩短生产周期,稳定产品品质。本研究以常见马拉糕预拌粉配方为基础,重点探究了发酵时间(0~70 min)对面糊pH、体积增长量、气泡分布、黏度的影响,以及不同蒸制强度(5~25 mL/min)对成品中心温度、比容、含水量、质构、内部气孔分布及感官品质等指标的影响。结果表明,发酵阶段,随着发酵时间的延长,20%、25%和30%含水量的面糊黏度先升高再降低,达到黏度最大值的时间分别为60、40和30 min;20%和25%含水量面糊的pH降低和体积增加趋势无显著差异(P>0.05),30%含水量面糊的p H降低速率变缓,发酵70 min后的体积增量(70.4 mL)只达到前两者各自增量(123.9 mL)的57%。面糊内部气泡直径总体增加,但单位面积内气泡数目下降15%~20%,气泡表面占有率没有明显变化,25%含水量面糊气泡大小分布范围最广。蒸制阶段,蒸制强度10 mL/min下马拉糕比容最大,20 mL/min下水分含量最高;蒸制强度低于15 mL/min,硬度、弹性、咀嚼性、回复性显著增加(P<0.05),继续加大蒸制强度,质构指标无显著变化(P>0.05);20 mL/min蒸制强度下成品具有较好的弹性和咀嚼性,且内部气孔较为均匀。综合发酵速度和面糊黏度、成品感官评分和质构特性,并从节能角度考虑,25%含水量的马拉糕预拌粉面糊发酵40 min,采用20 mL/min的蒸制强度可获得品质较好的产品。

The traditional processing steps of Mala cake are complicated and time-consuming,with low yield rate and unstable quality.However,the production of Mala cake using pre-mixed powder could effectively reduce the processing steps and maintain the product quality.The effect of fermentation time(0~70 min)on the pH value,volume growth,bubble distribution,and viscosity were determined.And the effect of different steaming intensity(5~25 mL/min)on central temperature,specific volume,water content,texture,stomatal distribution,and sensory quality of final product was also measured.The results showed that the viscosity of batter with 20%,25%,and 30% water content firstly increased and then decreased with the extension of fermentation time,reaching the maximum viscosity at 60,40 and 30 min,respectively.There was no significant difference(P>0.05)in the pH value and cake volume between batter with 20% and 25% water content.The pH of batter with 30% water content decreased slowly.After 70 min of fermentation,the volume increment(70.4 mL)was only 57% of the two former batters’volume increment(123.9 mL).The diameter of bubbles inside batter increased,but the number of bubbles per unit area decreased by 15%~20%,and the surface occupancy of bubbles did not change significantly.The size distribution of bubbles in batter with 25% water content was the highest.At the steaming stage,the specific volume of Mala cake was the highest at the steaming intensity of 10 mL/min,and the moisture content was the highest at the steaming intensity of 20 mL/min.When the steaming strength was lower than 15 mL/min,the hardness,elasticity,chewiness,and resilience were significantly increased with the increasing steaming strength(P<0.05).However,the texture index showed no significant(P>0.05)changes when the steaming intensity increased over 15 mL/min.Under the steam intensity of 20 mL/min,the final products showed higher elasticity and chewiness,and the internal pores were more uniform.Considering the fermentation speed,the rheological property of batter,the sensory evaluation,and texture of final products,and from the perspective of energy conservation,a better product quality could be obtained by fermenting the pre-mixed Mala cake batter with 25% water content for 40 min and then steaming at a steaming intensity of 20 mL/min.