为提高蓝莓的干燥速率及品质,探究了不同超声时间(10 min,20 min及30 min)对蓝莓的质地、细胞壁结构、果胶及纤维素酶活性、细胞壁多糖含量、水分状态及干燥特性与品质的影响。结果表明,超声处理20 min及30 min蓝莓果实的硬度值明显下降,细胞壁变皱褶疏松,果胶及纤维素酶活性明显下降。超声预处理促进了螯合态及碱溶态果胶向水溶态果胶转化,水溶态果胶含量提高了12.64%~34.36%。此外,超声预处理提高了蓝莓自由水的自由度,从而促进了水分的向外迁移。相比于对照组,超声预处理显著缩短了蓝莓中短波红外干燥时间(缩短了10.90%~27.24%),提高了酚类物质的保留及抗氧化能力。超声处理20 min蓝莓的干燥时间最短(22.7 h),酚类类物质保留率较高,抗氧化能力较强,是较为优良的超声预处理条件。研究可为提高蓝莓干燥品质提供理论依据。

To enhance the drying rate and quality of blueberries, this study investigated the effects of different ultrasonic durations (10 min, 20 min, and 30 min) on the texture, cell wall structure, pectin and cellulase activity, cell wall polysaccharide content, moisture status, and drying characteristics and quality of blueberries. The results indicated that the hardness values of blueberries treated with ultrasound for 20 min and 30 min significantly decreased, with the cell walls becoming wrinkled and loose. The activities of pectin and cellulase were markedly reduced. Ultrasonic pretreatment facilitated the conversion of chelated and Na₂CO₃-soluble pectin into water-soluble pectin, increasing the water-soluble pectin content by 12.64% to 34.36%. Furthermore, ultrasonic pretreatment increased the mobility of free water in blueberries, promoting moisture migration outward. Compared to the control group, ultrasonic pretreatment significantly reduced the mid-infrared drying time of blueberries (by 10.90% to 27.24%) and improved the retention of phenolic substances and antioxidant capacity. The drying time for blueberries treated with ultrasound for 20 min was the shortest (22.7 h), with a higher retention rate of phenolics and stronger antioxidant capacity, making it the optimal ultrasonic pretreatment condition. This study provides a theoretical basis for improving the drying quality of blueberries.

TS262.5

2022年河南省精品在线开发课程