PDF(Pubmed)
Abstract：
Egyptian Siwi dates dried using the open sun drying is exposed to different contaminants. So, the current study aims to use the closed solar dryer to improve Siwi date safety. The impact of washing and closed solar drying on the levels of microbial load, aflatoxins and heavy metals in Egyptian Siwi dates (ESD), in comparison to traditional open sun drying methods were examined. Two different drying techniques were employed to dry 300 kg of ESD. The microbial load was assessed following the two drying procedures. The levels of aflatoxins and heavy metals were analyzed using High-performance liquid chromatography (HPLC) and Inductively Coupled Plasma (ICP) techniques, respectively, after both drying methods. Additionally, the influence of storage time on the microbial load of the ESD was also evaluated using standard methods. The findings of the current study demonstrated that the closed solar drying significantly reduced the total bacterial and fungal counts by 96 % and 93 %, respectively, when compared to open sun-drying. No aflatoxins were detected in both fresh Siwi dates and Siwi dates dried using closed solar drying. However, after open sun drying, two aflatoxins; aflatoxin B1 (AFB1) and aflatoxin G1 (AFG1), were detected in the ESD, with concentrations of 0.95 and 0.23 μg kg-1, respectively. The closed solar drying significantly decreased the levels of lead (Pb), cadmium (Cd), copper (Cu), nickel (Ni), chromium (Cr), zinc (Zn), manganese (Mn), and iron (Fe) in the dried dates by 96 %, 94 %, 48 %, 71 %, 64 %, 4 %, 26 %, and 7 %, respectively, when compared to open sun drying. The stored Siwi dates that was exposed to the open sun drying showed a higher increase in bacterial (4.86 log CFU/g) and fungal (4.46 log CFU/g) counts. However, the stored Siwi dates that was exposed to the closed solar dryer showed a lower increase in bacterial (3.21 log CFU/g) and fungal (2.51 log CFU/g) counts. So, the duration of storage significantly impacted the microbial loads of the closed solar dried dates as compared to open sun drying. Overall, closed solar drying reduced the levels of investigated contaminants and extended the shelf life of ESD, thereby enhancing their safety for human consumption.
摘要：
使用露天干燥干燥的埃及Siwi日期暴露于不同的污染物。所以,目前的研究旨在使用封闭式太阳能干燥机来提高Siwi日期的安全性。洗涤和封闭式太阳能干燥对微生物负荷水平的影响，埃及锡威枣（ESD）中的黄曲霉毒素和重金属，与传统的开放式阳光干燥方法进行了比较。采用两种不同的干燥技术来干燥300kgESD。在两个干燥程序之后评估微生物负荷。使用高效液相色谱（HPLC）和电感耦合等离子体（ICP）技术分析了黄曲霉毒素和重金属的水平，分别,两种干燥方法后。此外,还使用标准方法评估了储存时间对ESD的微生物负荷的影响。目前的研究结果表明，封闭的太阳能干燥显著减少了96％和93％的细菌和真菌总数，分别,与开放式晒干相比。在新鲜的Siwi枣和使用封闭式太阳能干燥干燥的Siwi枣中均未检测到黄曲霉毒素。然而,露天晒干后，两种黄曲霉毒素；黄曲霉毒素B1(AFB1)和黄曲霉毒素G1(AFG1)，在ESD中检测到，浓度分别为0.95和0.23μgkg-1。封闭的太阳能干燥显着降低了铅（Pb）的水平，镉(Cd),铜(Cu),镍(Ni),铬(Cr),锌(Zn),锰(Mn),干枣中的铁（Fe）占96%，94%,48%,71%,64%,4%,26%,7%,分别,相比于露天晒干。暴露于公开阳光干燥的储存的Siwi日期显示细菌(4.86logCFU/g)和真菌(4.46logCFU/g)计数的更高增加。然而,暴露于密闭太阳能干燥器的储存的Siwi日期显示细菌（3.21logCFU/g）和真菌（2.51logCFU/g）计数的增加较低。所以,与开放式太阳干燥相比，储存时间显着影响了封闭的太阳干燥日期的微生物负荷。总的来说,封闭式太阳能干燥降低了所研究污染物的水平，延长了ESD的保质期，从而提高人类消费的安全性。
