目的:本研究建立并优化山药(Chinese yam,CY)超高压(Ultra-high pressure,UHP)预处理联合热风干燥(Hot air drying,HAD)工艺,以期缩短山药干燥时间并提高山药品质.方法:以干燥时间、复水比、色差值、多糖及总酚含量为指标,通过单因素实验探讨不同超高压压力、保压时间及干燥温度条件对山药干燥时间的影响,利用CRITIC法计算各指标的权重系数和不同条件下山药综合评分,并以综合评分为响应值,通过响应面法优化超高压预处理联合热风干燥的加工工艺.结果:超高压预处理能显著缩短干燥时间(P＜0.05)并提高山药品质,山药干燥时间、复水比、总酚含量、色差值和多糖含量所占权重分别为0.34、0.19、0.19、0.14、0.14,最佳工艺参数为压力380 MPa、保压时间9 min、干燥温度50℃,该条件下验证试验各指标结果分别为干燥时间400±17.32 min、复水比 2.18±0.04g/g、色差值 6.02±0.18、多糖含量 78.08±1.33 mg/g、总酚含量 2.77±0.16 mg/g 和山药综合评分74.75±2.40,验证结果与预测值的相对标准偏差(Relative standard deviation,RSD)为2.71％,说明该模型具有良好的预测性.结论:该研究建立了一种高效节能的超高压预处理联合热风干燥工艺,可为山药加工规范化研究及应用提供新思路.
Abstract
Objective:The ultra-high pressure(UHP)pretreatment combined with hot air drying(HAD)process of Chinese yam(CY)was established and optimized in this study,in order to shorten the drying time of CY and improve its quality.Methods:The drying time,rehydration ratio(RR),color difference value,polysaccharide and total phenol content(TPC)were used as indicators to investigate the effects of different UHP pressure,holding time and drying temperature conditions on CY processing by single factor experiment,the weight coefficient of five indicators and the comprehensive score under different conditions were calculated by the CRITIC method,using the comprehensive score as the response value to optimize the processing technology of UHP pretreatment combined with HAD by response surface methodology.Results:UHP pretreatment could significantly shorten the drying time(P＜0.05)and improve the quality of CY.The weights of drying time,RR,TPC,color difference value and polysaccharide content of CY were 0.34,0.19,0.19,0.14 and 0.14,respectively.The optimal process parameters were determined as follows:Pressure 380 MPa,holding time 9 minutes,drying temperature 50 ℃.Under these conditions,the results of the validation experiment for each indicator were drying time of 400±17.32 min,RR of 2.18±0.04 g/g,color difference value of 6.02±0.18,polysaccharide content of 78.08±1.33 mg/g,TPC of 2.77±0.16 mg/g,and comprehensive score of 74.75±2.40.The relative standard deviation(RSD)between the validation result and the predicted value was 2.71％,indicating that the model had good predictability.Conclusion:This study established an efficient and energy-saving UHP-HAD drying process of CY,which would provide new ideas for the standardized research and application of CY processing.
关键词
山药/超高压预处理/干燥/CRITIC法/响应面试验
Key words
Chinese yam/ultrahigh pressure pretreatment/drying/CRITIC law/response surface methodology
维普
万方数据