Effect of hot air drying process on the cracks and quality of jujubes

Authors

• Hu Linbin, College of Mechanical and Electronic Engineering , Tarim University , Alaer , Xinjiang 843300 , China;Modern Agricultural Engineering Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region , Alaer , Xinjiang 843300 , China;Xinjiang Production and Construction Corps (XPCC ) Key Laboratory of Utilization and Equipment of Special Agricultural and Forestry Products in Southern Xinjiang , Alaer , Xinjiang 843300 , China
• Li Lin, Xinjiang University of Technology , Hetian , Xinjiang 848000 , China
• Wang Long, College of Mechanical and Electronic Engineering , Tarim University , Alaer , Xinjiang 843300 , China;Modern Agricultural Engineering Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region , Alaer , Xinjiang 843300 , China;Xinjiang Production and Construction Corps (XPCC ) Key Laboratory of Utilization and Equipment of Special Agricultural and Forestry Products in Southern Xinjiang , Alaer , Xinjiang 843300 , China
• Hu Can, College of Mechanical and Electronic Engineering , Tarim University , Alaer , Xinjiang 843300 , China;Modern Agricultural Engineering Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region , Alaer , Xinjiang 843300 , China;Xinjiang Production and Construction Corps (XPCC ) Key Laboratory of Utilization and Equipment of Special Agricultural and Forestry Products in Southern Xinjiang , Alaer , Xinjiang 843300 , China
• Yi Xiaokang, College of Mechanical and Electronic Engineering , Tarim University , Alaer , Xinjiang 843300 , China;Modern Agricultural Engineering Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region , Alaer , Xinjiang 843300 , China;Xinjiang Production and Construction Corps (XPCC ) Key Laboratory of Utilization and Equipment of Special Agricultural and Forestry Products in Southern Xinjiang , Alaer , Xinjiang 843300 , ChinaFollow

Corresponding Author(s)

弋晓康（1976—），男，塔里木大学教授，博士。E-mail：yxk@taru.edu.cn

Abstract

[Objective] To investigate the crack occurrence in jujubes under different hot air drying conditions and the resulting quality differences. [Methods] Jujubes of Xinjiang are taken as the research objects. Based on hot air drying technology, three drying temperature and wind speed levels are set up to explore the drying characteristics and quality changes of crack-free and cracked jujubes under different drying conditions. [Results] Under hot-air drying conditions, the drying rate can be accelerated by increasing drying temperature and wind speed. Compared to crack-free jujubes, cracked ones are prone to moisture loss, thus requiring shorter drying times. Increases in temperature and wind speed enhance the effective moisture diffusion coefficient. The initial crack rate of fresh jujube samples is between 35% and 55%. The newly added crack rates of crack-free jujubes after drying at 65 ℃ (with a fixed air drying wind speed) and 2.0 m/s (with a fixed drying temperature) are 30% and 20%, respectively. Under the same conditions, no new cracks occur in the cracked jujubes after drying. As drying temperature and wind speed are increased, total sugar, total acid, and ascorbic acid content, as well as L*, a*, and b* values decrease, while reducing sugar content and △E show the opposite trend. [Conclusion] Increased drying temperature and drying wind speed shorten the drying time of jujubes and influence crack occurrence, but the resulting cracks do not affect jujube quality.

Publication Date

7-25-2026

First Page

194

Last Page

202

DOI

10.13652/j.spjx.1003.5788.2025.80493

Recommended Citation

Linbin, Hu; Lin, Li; Long, Wang; Can, Hu; and Xiaokang, Yi (2026) "Effect of hot air drying process on the cracks and quality of jujubes," Food and Machinery: Vol. 42: Iss. 7, Article 24.
DOI: 10.13652/j.spjx.1003.5788.2025.80493
Available at: https://www.ifoodmm.cn/journal/vol42/iss7/24

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