Optimization of process conditions for vacuum microwave drying of lemon peel by response surface methodology: Quality characteristics and volatile compounds

摘要

This study evaluated for to optimization of dried lemon peel production conditions in vacuum microwave dryer as a novel drying technique by using response surface methodology (RSM) and to observation of its effects on the quality and volatile compounds. The optimum vacuum power (584 watt) and temperature (50 degrees C) according to the highest b* value and limonene content while the minimum drying time occurs were estimated using RSM. The volatile constituents of fresh and dried lemon peels were investigated by headspace-solid phase micro extraction-gas chromatography mass spectrometry, as a result, 32 and 34 compounds were identified, respectively. Furthermore, quality characteristics of the optimally developed lemon powder were studied. Dried peels had higher conservation of total phenolic compounds than fresh samples. Drying significantly affected the volatile compounds, antioxidant activity, total carotenoid, and ascorbic acid contents of lemon peel powders. Practical applications Drying is an important food preservation method. However, the effets of drying methods and conditions on foods quality are not clear. This study presents optimum conditions for drying lemon peels in vacuum microwave dryer and appreciates effect of drying system on some quality characteristics and volatile compounds. The data of present study will give information to food industry for installing industrial scale drying systems for aromatic products. It will be contributed to the improvement of firms' conditions that already in production.