Effect of Alkaline Electrolytic Water Pretreatment on Temperature-and Humidity-controlled Hot Air Drying Quality of Wolfberry
The high energy consumption and quality degradation caused by low drying efficiency pose significant challenges in hot-air drying processing of fruits and vegetables.To enhance the hot-air drying quality of wolfberry,pretreatment with different alkaline media soaking methods(3％Na2CO3 and alkaline electrolyzed water soaking for 1 min,10 min,and 20 min,respectively,was employed.The hot-air drying characteristics,microstructure,color,rehydration ratio,shrinkage,and nutritional content of wolfberry were investigated.The results revealed that compared with the control group,alkaline electrolyzed water pretreatment significantly reduced the hot air-drying time required for wolfberries(P＜0.05),with the shortest drying time observed in group treated by 10 min soaking of alkaline electrolyzed water.This group achieved a higher drying rate and an effective moisture diffusivity of 5.020×10-8 m2/min.After alkaline electrolyzed water pretreatment,the gaps between the waxy stripes on the epidermis were enlarged,with some stripes even dissolving or breaking.When pretreated with alkaline electrolyzed water for 10 min,the hot-air dried wolfberry exhibited the closest color to fresh samples,coupled with superior rehydration capabilities,reduced shrinkage and significantly elevated levels of polysaccharides(9.79％),total phenols(4.18 m g/g),and total flavonoids(6.42 mg/g)compared with the control(P＜0.05).Pectin composition underwent notable transformations upon alkaline electrolyzed water pretreatment and drying.While fresh wolfberry primarily contained sodium carbonate-soluble pectin(SSP),the content of chelator-soluble pectin(CSP)increased post-treatment,suggesting a reconfiguration of pectin fractions.In conclusion,pretreating wolfberries with alkaline electrolyzed water for 10 min produced the hot-air dried wolfberries with best quality.The research result can not only present a straightforward and effective pretreatment strategy for improving the hot-air drying of wolfberry but also can offer a green and environmentally benign approach for enhancing the quality and efficiency of drying processes for a wide range of fruits and vegetables.
wolfberryalkaline electrolyzed water pretreatmenttemperature-and humidity-controlled hot air drying
国家科技期刊平台
NSTL
万方数据
