Effect of the ripening stage on the pulsed vacuum drying behavior of goji berry (Lycium barbarum L.): Ultrastructure, drying characteristics, and browning mechanism

An-An Zhang; Long Xie; Qing-Hui Wang; Ming-Qiang Xu; Yan Pan; Zhi-An Zheng; Wei-Qiao Lv; Hong-Wei Xiao

doi:10.1016/j.foodchem.2024.138489

Effect of the ripening stage on the pulsed vacuum drying behavior of goji berry (Lycium barbarum L.): Ultrastructure, drying characteristics, and browning mechanism

Food Chem. 2024 Jun 1:442:138489. doi: 10.1016/j.foodchem.2024.138489. Epub 2024 Jan 19.

Authors

An-An Zhang¹, Long Xie², Qing-Hui Wang³, Ming-Qiang Xu⁴, Yan Pan⁵, Zhi-An Zheng¹, Wei-Qiao Lv², Hong-Wei Xiao⁶

Affiliations

¹ College of Engineering, China Agricultural University, P.O. Box 194, 17 Qinghua Donglu, Beijing 100083, China.
² Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China.
³ Agricultural Mechanization Institute, Xinjiang Academy of Agricultural Sciences, Urumqi, China.
⁴ College of Engineering, China Agricultural University, P.O. Box 194, 17 Qinghua Donglu, Beijing 100083, China; Institute of Agro-products Storage and Processing, Xinjiang Academy of Agricultural Sciences, Urumqi, Xinjiang, China.
⁵ Institute of Agro-products Storage and Processing, Xinjiang Academy of Agricultural Sciences, Urumqi, Xinjiang, China.
⁶ College of Engineering, China Agricultural University, P.O. Box 194, 17 Qinghua Donglu, Beijing 100083, China. Electronic address: xhwcaugxy@163.com.

PMID: 38278104
DOI: 10.1016/j.foodchem.2024.138489

Abstract

In current work, the effect of ripening stages (I, II, and III) on pulsed vacuum drying (PVD) behavior of goji berry was explored. The shortest drying time of goji berry was observed at stage I (6.99 h) which was 13.95 %, and 28.85 % shorter than those at stages II, and III, respectively. This phenomenon was closely associated with the ripening stage, as contributed by the initial physiochemical differences, ultrastructure alterations, and moisture distribution. In addition, lower maturity suffered more severe browning, primarily due to the enzymatic and non-enzymatic reactions of phenolics, followed by pigment degradation and the Maillard reaction. Additionally, the PVD process promoted the rupture and transformation of the pectin fractions, also causing browning either directly or indirectly through participation in other chemical reactions. These findings suggest that the appropriate ripening stage of goji berry should be considered as having a significant impact on drying behaviors and quality attributes.

Keywords: Browning mechanism; Drying behavior; Goji berry; Pulse vacuum drying; Ripening stage; Ultrastructure.

MeSH terms

Lycium* / chemistry
Vacuum