Abdelkarim Diaeldin O, Mohamed Ahmed Isam A, Ahmed Khaled A, Younis Mahmoud, Yehia Hany M, Zein El-Abedein Assem I, Alhamdan Abdulla
Chair of Dates Industry & Technology, King Saud University, Riyadh 11451, Saudi Arabia.
Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia.
Plants (Basel). 2022 Aug 4;11(15):2029. doi: 10.3390/plants11152029.
The Barhi date is a high-quality date cultivar whose fruits (dates) are plucked and eaten fresh when they reach the Khalal maturity stage due to their sweetness, crispiness, and yellow skin color. After harvesting, Khalal Barhi fruits rapidly matured to the Rutab stage, where their tissues become soft and their skin color browner. This results in a decrease in their market value and customer demand. This study aims at investigating the effectiveness of the postharvest ultrasonic treatment in conserving the physical, microbial, and nutritional quality of Barhi fruits and extending their shelf life. To achieve the goals of the present work, the response surface methodology (RSM) was used for the optimization of the ultrasonic intensity (50, 100, 150, and 200 W/cm) and application time (5, 10, 15, and 20 min) to preserve the Barhi dates high quality features for varied storage temperatures (1, 5, 15, and 25 °C) and duration (1, 6, 16, and 21 days). In RSM, a four-factors-mixed-levels central composite rotatable design (CCRD) was applied to optimize the ultrasound treatment and storage environments for better-quality physical [total soluble solids (TSS), firmness, and total color changes (ΔE)], microbial [total viable count (TVC)], nutritional [total phenolic content (TPC), DPPH antiradical activity, glucose, and fructose] features of Barhi dates. The outcomes showed that ultrasound intensity and its application time, storage temperature, and storage period influence the physical, microbial, and nutritional quality attributes in different magnitudes. The ideal settings for lessening the changes in the physical attributes, eliminating the microbial growth, and improving the nutritional quality attributes were 140 W/cm, 5.2 min, 20.9 °C, and 21 days for ultrasound intensity, ultrasound exposure duration, storage temperature, and storage duration, respectively. In conclusion, this study proved the potential application of ultrasound for persevering the excellence aspects of Barhi dates and identified the ideal ultrasound environments for maintaining the physical, microbial, and nutritional quality features of Barhi dates during extended storing.
巴尔希枣是一种优质枣品种，其果实（枣）在达到哈勒尔成熟阶段时，因其甜度、脆度和黄色果皮而被采摘并新鲜食用。收获后，哈勒尔阶段的巴尔希枣果实迅速成熟至鲁塔卜阶段，此时其组织变软，果皮颜色变深。这导致其市场价值和客户需求下降。本研究旨在调查采后超声处理对保持巴尔希枣果实的物理、微生物和营养品质以及延长其货架期的有效性。为实现本研究的目标，采用响应面法（RSM）优化超声强度（50、100、150和200W/cm）和处理时间（5、10、15和20分钟），以在不同储存温度（1、5、15和25℃）和储存时间（1、6、16和21天）下保持巴尔希枣的高品质特性。在RSM中，采用四因素混合水平中心复合旋转设计（CCRD）来优化超声处理和储存环境，以获得品质更佳的巴尔希枣的物理特性[总可溶性固形物（TSS）、硬度和总颜色变化（ΔE）]、微生物特性[总活菌数（TVC）]、营养特性[总酚含量（TPC）、DPPH抗自由基活性、葡萄糖和果糖]。结果表明，超声强度及其处理时间、储存温度和储存期对物理、微生物和营养品质属性有不同程度的影响。超声强度、超声处理时间、储存温度和储存时间的理想设置分别为140W/cm、5.2分钟、20.9℃和21天，以减少物理属性的变化、消除微生物生长并改善营养品质属性。总之，本研究证明了超声在保持巴尔希枣优良品质方面的潜在应用，并确定了在延长储存期间保持巴尔希枣物理、微生物和营养品质特性的理想超声环境。
