基于电子鼻气味检测的苹果微波干燥方案优选  

Optimization of control strategy of microwave drying for apple based on online volatile measurement with electronic nose

作　　者：李静[1,2] 宋飞虎[1,2] 浦宏杰[1,2] 徐晚秀 李臻锋 

机构地区：[1]江南大学机械工程学院,江苏省食品先进制造装备重点实验室,无锡214122 [2]绍兴县魁联机电科技有限公司,绍兴312000

出　　处：《农业工程学报》2015年第3期312-318,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然基金项目(21206051);江苏省产学研联合创新资金(BY20130155-22);江苏省普通高校研究生科研创新计划项目(KYLX_1158)

摘　　要：微波干燥中,过程参数设置不当会引起物料结构破坏和表面焦糊,期间往往伴随着特征气味的散发。该文以苹果为对象,采用60、70、80℃恒温、模糊逻辑控制和线性温度控制5种干燥方案,通过电子鼻采集的气味图谱,研究特征气味的散发规律,及优化干燥方案。根据恒温方案气味图谱中苹果风味峰和焦糊峰的变化规律,确定的模糊逻辑控制方案,可实现在线调节磁控管功率,保留风味、减少焦糊。将模糊逻辑控制方案中实测物料温度曲线进行优化,确定的线性温度控制方案,省去电子鼻检测环节,更适合工业应用。通过比较不同微波干燥方案下的产品品质,线性温度控制方案下干燥产品的品质高、耗时合理、干燥能力强,为优先方案。该研究为气味检测技术应用于苹果干燥提供了技术依据。Apple is widely cultivated in China for its characteristic flavor. In order to prolong the shelf life of harvested apple, the use of the method of dehydration drying to preserve product is a common way. Since the early study in 1920 s, more than 300 volatile compounds have been identified as aroma substances from various cultivars of apples. Within these numerous compounds, only a few have been determined to have a decisive impact on the sensory quality. However, only a few exhaustive studies of apple aroma during the drying process have been published; moreover, the present analyses are all restricted to offline detection of apple aroma volatiles and no online measurement has been reported. Although the offline volatiles detection can provide some useful information, it is inconvenient and time-consuming. In addition, the methods are all impossible to provide control parameters to optimize drying conditions in real time and in situ to improve volatiles control with online measurement. Compared with other drying methods, microwave drying is used more extensively due to its advantages of high efficiency and short time-consumption. However, microstructure of the object may be destroyed and the surface may be burnt under improper drying parameters, leading to the emission of corresponding volatiles. During the drying process, an electronic nose（z NoseTM） was used to carry out online detection of the smell spectrum, where four significant peaks could be extracted. Peak 1 and Peak 2, i.e. ＂natural peak＂ could be detected from both fresh and burnt apples. Peak 3 and Peak 4, i.e. ＂burning peak＂ appeared only in the spectrum of burnt apple. Apple cubes were first dried at three fixed temperatures（60, 70 and 80℃）. At 60℃, ＂natural peak＂ and ＂burning peak＂ were kept small in the whole drying process. At 80℃, higher ＂natural peak＂ indicated more loss of aroma volatiles, and higher ＂burning peak＂ indicated that more burnt appeared. Fuzzy logic controller was designed with the input of Pe

关 键 词：微波 干燥 温度 气味检测 控制方案 苹果 

分 类 号：TS255[轻工技术与工程—农产品加工及贮藏工程]