干燥温度及氧气含量对胡萝卜气调干燥特性的影响-食品科学.PDF

20 2014, Vol.35, No.23 食品科学 ※基础研究 干燥温度及氧气含量对胡萝卜气调 干燥特性的影响 * 种翠娟，刘云宏 ，朱文学，罗 磊 （河南科技大学食品与生物工程学院，河南洛阳 471023 ） 摘  要：为探讨干燥温度及氧气含量对胡萝卜气调干燥特性的影响，进行氮气气调热风干燥实验研究。结果表明： 提高干燥温度可显著缩短干燥时间；当氧气含量由20.9%降至5%，对流传质系数维持不变，而对流传热系数约增大 0.5%；胡萝卜素含量随着氧气含量及干燥温度的下降而升高，氧气含量低至5%可有效减缓干燥过程中胡萝卜素的 % % E % % 氧化降解；在40～60 ℃区间，5 及10 氧气含量条件下的总色差（ Δ ）值要明显低于15 及20.9 氧气含量条件 E 下的Δ 值，表明低氧气调热风干燥可有效保护产品色泽。因此，采用气调干燥技术有利于获得高品质的胡萝卜干 燥产品。 关键词：气调干燥；胡萝卜；干燥特性 Effect of Drying Temperature and Oxygen Content on Modified Atmosphere Drying Characteristics of Carrots * CHONG Cui-juan, LIU Yun-hong , ZHU Wen-xue, LUO Lei (College of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471023, China) Abstract: To investigate the effects of drying temperature and oxygen content on modified atmosphere-drying characteristics of carrots, a modified atmosphere dryer was used in this study, in which N2 was used as a drying medium to replace partial air. The results showed that increasing drying temperature could shorten the drying time significantly. As the oxygen content decreased from 20.9% to 5%, the mass transfer coefficient remained the same, yet the heat transfer coefficient increased by about 0.5%; as drying temperature and oxygen content decreased, the carotenoid content increased, and the oxidative degradation of carotenoid could be restrained when the oxygen content of drying medium was as low as 5%. With the drying temperatures