Abstract

At present, the drying methods for jujube powder consists of powder process after jujube dryness and powder process after concentrating jujube juice. In order to obtain jujube powder with small particle size, good rehydration, higher VC content and better color, this study proposes to adopt different drying methods, namely, first carry out preliminary cooling against the jujube pieces at low temperature before drying and then take the secondary cooling method during the drying process, in order to make jujube pieces brittle and get superfine jujube powder. After comparing the jujube powder prepared through ordinary drying methods and the drying method of low-temperature superfine grinding, results show that in terms of physical properties, the latter may get smaller particle size, lighten color and better tastes of jujube powder particle than the former; in terms of nutrient content, the latter has relatively higher reducing sugar and total sugar contents. Therefore, the second drying method is superior to the first one. In this context, this study analyzes the structure, drying principle and force required by the drying process of drying equipment of low-temperature superfine grinding system. In the design process of grinding system, this study attempts to separate the nucleation and growth process of powder particles into different parts for drying equipment, in order to effectively control the particle size of jujube powder, reduce the particle agglomeration when collecting the jujube powder and improve the quality and uniformity of jujube powder.

Keywords:

Brittleness, low temperature, red jujube, superfine crushing,

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Competing interests

The authors have no competing interests.

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