Maturation characteristics and quality evaluation of Huizao jujube from six producing areas in Southern Xinjiang

【Objective】Huizao jujube, originating from Xinzheng, Henan Province, was introduced to Xinjiang in the early 1970s and has now become the dominant dried jujube cultivar in the region. To better support the high - quality cultivation and production of Huizao in southern Xinjiang, this study systematically investigated the mature quality characteristics of Huizao from different producing areas and their suitable cultivation patterns.【Methods】Using Huizao fruits from different producing areas in southern Xinjiang as the research subject, analysis of variance, correlation analysis, and principal component analysis were used to explore the mature quality characteristics of Huizao fruits from different regions, the influence of cultivation patterns on Huizao quality, and to establish maturity kinetic models for Huizao from different producing areas.【Results】There were certain differences in various quality indicators of Huizao from different producing areas. The single fruit mass was highest in Yecheng Huizao (7.54 g) and lowest in Wensu Huizao (5.76 g). The longitudinal diameter was largest in Maigaiti Huizao (36.79 mm) and smallest in Alaer Huizao (31.75 mm). The transverse diameter was larger in Maigaiti (23.81 mm), Yecheng (23.33 mm), and Luopu Huizao (23.03 mm), while the smallest value was recorded in Wensu Huizao (20.79 mm). The brightness value (L) was higher in Yecheng (27.67), Maigaiti (27.57), and Qiemo Huizao (26.00), and the lowest in Luopu Huizao (14.13). In terms of sugar and acid content, Qiemo Huizao had a relatively high titratable acid content (0.32% ), while Yecheng Huizao had a lower one (0.21%). In sparse - planting orchards, Yecheng Huizao had the highest soluble sugar content (76.79% ), while Wensu Huizao had the lowest (46.25% ). Among the sugar- acid ratios, Yecheng Huizao recorded the highest value at 344.50, while Wensu Huizao had the lowest at 128.38. In dense planting orchards, the sugar-acid ratio was higher in Wensu (317.88), Alaer (312.84), and Luopu Huizao (307.22), while it was lower in Maigaiti (269.98), Yecheng (271.86), and Qiemo Huizao (256.39). The hardness was higher in Wensu, Alaer, Maigaiti, Yecheng, and Qiemo Huizao, with the lowest value observed in Luopu Huizao. The springiness was higher in Qiemo and Luopu Huizao, while it was lower in Wensu and other producing areas. The cohesiveness of Huizao was higher in Wensu and Maigaiti, while it was lower in Luopu and Qiemo. The gumminess was higher in Wensu, Alaer, and Maigaiti Huizao, while the lowest level was observed in Luopu Huizao. According to the comprehensive evaluation results, the fruit quality ranked from high to low is as follows: Maigaiti, Yecheng, Qiemo, Alaer, Wensu, Luopu. The quality characteristics of Huizao varied with cultivation patterns across different producing areas: Wensu Huizao showed significant differences in single fruit mass, brightness value (L), and soluble sugar content between dense and sparse planting. Alaer Huizao exhibited significant differences in brightness value (L), gumminess, and soluble sugar content between sparse and dense planting. Maigaiti Huizao exhibited significant differences in single fruit mass, brightness value (L), and soluble sugar content between close and sparse planting. Yecheng Huizao showed significant differences in single fruit mass, brightness value (L), gumminess, and soluble sugar content under the two planting densities. Luopu Huizao showed a significant difference only in soluble sugar content between sparse and dense planting. Qiemo Huizao exhibited significant differences in single fruit mass, brightness value (L), springiness, gumminess, and soluble sugar content because of planting density. Comprehensive evaluation results indicated that Qiemo and Yecheng Huizao performed better under sparse planting conditions, while Wensu, Alaer, Maigaiti, and Luopu Huizao achieved higher scores under dense planting conditions. The maturity kinetic models of Huizao varied among producing areas: In Maigaiti, the total soluble sugar content of Huizao showed a significant negative correlation with water content (R2 = 0.809, P＜0.05). As the water content decreased from 63.45% to 20.98%, the total soluble sugar content increased non - linearly from 39.27% to 89.48%. In Qiemo, the total soluble sugar content of Huizao also showed a significant negative correlation with water content (R2 = 0.712, P ＜ 0.05). When the water content decreased from 59.19% to 20.39%, the total soluble sugar content increased non - linearly from 29.45% to 85.12%. In Yecheng, the total soluble sugar content of Huizao was significantly negatively correlated with the water content (R2 = 0.774, P ＜ 0.05). As the water content declined from 53.23% to 18.98%, the total soluble sugar content increased non - linearly from 29.23% to 73.52%.【Conclusion】 Climatic conditions vary significantly among production regions in southern Xinjiang, which affects the growth and development of Huizao, as well as the quality formation and retention during maturation and drying. Consequently, Huizao from different regions exhibits marked differences in quality and suitable cultivation patterns. The maturity kinetic model can serve as a simplified alternative method for evaluating Huizao quality. The research results would provide data support for the high - quality development of Huizao in southern Xinjiang.