超声处理对中短波红外干燥红枣时间及品质的影响.pdfVIP

74 2015， 协1. 36， No.08 ※王艺技术 画画翻事 超声处理对中短波红外于燥红枣时间及 品质的影响 陈文敏，彭星星，马婷，杨泽龙，徐怀德* (西北农林科技大学食品科学与工程学院，陕西杨凌 7121∞) 摘 要:为提高红枣干燥品质，减少干燥时间，以干燥时间为响应值，响应面优化得到红枣中短波红外干燥前超 声处理条件为:频率40 kHz、时间40min、功率350W。最优超声处理后中短波红外干燥红枣至其干基含水率约为 40%时所需干燥时间为9.55 h; 未超声处理中短波红外干燥需13.33 h; 传统热风干燥需17.13 h。扫描电镜观察红枣 果皮，超声处理40min使果皮表面产生大量裂缝，表皮层变薄，仅38.8μm，表皮层和亚表皮层易分离，利于干燥 过程中水分扩散，显著缩短中短波红外干燥时间。红枣超声处理后中短波红外干燥的干制品品质显著优于未超声处 理红外干燥，极显著优于传统热风干燥。最优超声处理条件结合中短波红外干燥，所得干制品在3 种处理方式中总 VC、总酸、总黄嗣含量最高，糖酸比最高，色泽最忧，能耗最少，是适合红枣干燥的技术方法。 关键词:超声波处理:中短波红外干燥:红枣:时间:品质 Impact of Ultrasonic Treatment on Drying Time and Quality of Red J时ubes Dried by Medium- and Short-Wavelength Infrared Radiation CI面N Wenmin , PENG Xingxi吨， MA Ting, YANG Zelong, XU Huaide * (College of F，∞d Science and Engineeri吨， Northwest AF University , Yangling 7121∞， China) Abstrad: In order to improve the quality of dried products and reduce the drying time , red j时ubes were subjected to ultrasonic treatment before medium- and short-wavelength infrared drying. The optimal conditions for ultrasonic pretreatment determined by response surface methodology were 40 kHz, 40 min and 350 W. The drying time to reach a moisture content of 40% by medium- and short-wavelength infrared radiation was 9.55 and 13.33 h with and without ul位asonic pretreatment, respectively, while the drying time for untreated samples by 位aditional hot air drying was 17.13 h. A负er ul位asonic treatment for 40 min , red jujube peel produced a large number of cracks and became thin , only 38.8μnin 出ickness， and were eωily separated into cuticul缸