紫薯曲奇饼干品质和加工工艺研究

Quality and Processing Technology of Purple Sweet Potato Cookies

以紫薯粉、小麦标准粉、黄油、鸡蛋、糖粉为原料,采用单因素和正交试验设计,对紫薯混合粉的流变学特性,紫薯曲奇饼干的抗氧化性、质构特性、感官品质等测定分析,研究确定紫薯黄油曲奇饼干的最佳紫薯粉添加量、最佳配方和加工工艺。结果表明:紫薯粉的添加量与混合粉的形成时间、稳定时间、面粉的吸水率呈负相关,与面筋的弱化度、面团的延伸性呈正相关;紫薯粉有利于面筋的弱化,适宜加工曲奇饼干;紫薯粉能降低黄油曲奇饼干贮藏期间的抗氧化值。添加50%~70%的紫薯粉可以改善黄油曲奇饼干的硬度、黏聚性、咀嚼性、感官性状,最佳配方为:紫薯粉60g (小麦标准粉40g)、鸡蛋75g、黄油70g、糖粉40g。最佳搅打工艺为:先打发鸡蛋与糖粉至奶油状,然后加入黄油搅打至粘稠的絮状,再拌入紫薯粉与小麦标准粉的混合粉;单个重10~12g的湿饼坯最佳烘烤温度为上火155~160℃、下火170℃、烘烤时间12min。

The effects of purple sweet potato powder on the quality and processing technology of cookies were studied.In order to determine the optimum formula and processing technology,single factor and orthogonal design were used to measure the rheological properties of purple potato powder,the antioxidant activity of purple potato cookies as well as the texture properties and sensory quality,while the wheat flour cookies was used as control.Results showed that the amount of purple sweet potato powder was negatively related to the formation time,the stability time,and the water absorption rate of the flour,and positively linked to the weakening degree of the gluten and the extension of the dough.Additionally,the purple potato powder was beneficial to the weakening of the gluten and suitable for processing cookies.Besides,purple sweet potato powder could reduce the antioxidant value of butter cookies during storage.Based on the result,the addition of 50%~70% purple potato powder could improve the hardness,cohesiveness,chewiness and sensory properties of cookies.The best formula was purple sweet potato powder 60 g(wheat flour 40 g),egg 75 g,butter 70 g,sugar 40 g.The best mixing process was first whip the egg and the sugar powder into the cream,and then add butter and stir the mixture to the sticky floc,subsequently mix the mixed powder of purple sweet potato powder and wheat flour into the mixture.Finally,each wet cake weighed about 10~12 g,and the optimal condition was 155~160℃(upper temperature) and 170℃(lower temperature) for 12 min.