Abdelhak Marwa, Al-Bedak Osama Abdel-Hafeez Mohamed, Abdelmoez Mahmoud N, Abdellah Adel Ahmed, Abdel-Rahman El-Sayed A, El-Wahab Mohamed M Abd
Department of Science and Technology of Sugar Industry, Faculty of Sugar and Integrated Industries Technology, Assiut University, Assiut, 71511, Egypt.
Assiut University Mycological Centre (AUMC), Assiut University, Assiut, 71511, Egypt.
Sci Rep. 2025 May 16;15(1):17095. doi: 10.1038/s41598-025-99870-4.
In hot-weather regions such as Egypt, where maintaining lower storage temperatures is both economically unfeasible and a significantly difficult, this study was directed towards optimizing the storage of beet thick juice in order to enhance white sugar yield and reduce the impact of climate change. In this study, a pilot plant consisting of 12 storage cylinders was used to maintain thick beet juice with total soluble solids (ºBrix) of 67, 68, and 69 at 15, 25, and 35 ºC, respectively. Betastab XL (Hop ß-acids) and KEBOCID 310 (sodium dimethyldithiocarbamate) were employed as biocides at 40 ppm. Surface sealing using 25.0% NaOH along with air removal was also applied. The relationships between bacterial count (CFUs), pH, lactic acid (LA) concentration, and reducing sugars (RS) content were evaluated. CFUs increased gradually with the length of the storage period in all tanks, reaching its peak (350 CFU/mL) in the control tank at 35 °C. LA and RS values were determined in all tanks and occurred at very low concentrations. pH exhibited a stable behavior with the exception of the control tank at 35 ºC that displayed degradation correlated to a pH drop to 7.32. Species of bacteria associated with the stored thick juice were isolated and identified by sequencing the 16 S rRNA. These included Bacillus cereus, B. licheniformis, B. paralicheniformis, B. subtilis, Bordetella muralis, Brevibacillus agri, Pseudomonas juntendi, and Stenotrophomonas geniculata. Antibacterial activity of both biocides at three concentrations-20, 40, and 60 ppm-was investigated against the species isolated. Hop ß-acid concentrations showed significant effects on the investigated bacteria with the exception of B. muralis and P. juntendi. All bacteria, with the exception of B. licheniformis AUMC B-550, were significantly affected by KEBOCID 310 concentrations. However, S. geniculata responded negatively to 20 ppm of KEBOCID 310. For the investigated strains, the effects of KEBOCID 310 at 40 and 60 ppm were almost identical. Along with better control over juice solids content and storage temperature, identifying the source and type of the bacterial infection can assist with managing the process and reduce thick juice deterioration. Sugar industry designers could potentially benefit from this study's elucidation of the ideal circumstances for cost-effective storage in hot temperature zones.
在埃及等炎热气候地区，维持较低的储存温度在经济上既不可行，难度也极大。本研究旨在优化甜菜浓汁的储存，以提高白砂糖产量并减少气候变化的影响。在本研究中，一个由12个储存罐组成的中试装置被用于分别在15℃、25℃和35℃下储存总可溶性固形物（°Brix）为67、68和69的甜菜浓汁。以40 ppm的浓度使用了Betastab XL（啤酒花β-酸）和KEBOCID 310（二甲基二硫代氨基甲酸钠）作为杀菌剂。还采用了25.0%的NaOH进行表面密封并去除空气。评估了细菌计数（CFUs）、pH值、乳酸（LA）浓度和还原糖（RS）含量之间的关系。在所有储存罐中，CFUs均随着储存期的延长而逐渐增加，在35℃的对照罐中达到峰值（350 CFU/mL）。在所有储存罐中均测定了LA和RS值，且浓度极低。除了35℃的对照罐pH值降至7.32并出现降解外，pH值表现稳定。通过对16S rRNA进行测序，分离并鉴定了与储存的浓汁相关的细菌种类。这些细菌包括蜡样芽孢杆菌、地衣芽孢杆菌、类地衣芽孢杆菌、枯草芽孢杆菌、壁氏博德特氏菌、农业短芽孢杆菌、琼氏假单胞菌和膝状寡养单胞菌。研究了两种杀菌剂在20、40和60 ppm三种浓度下对分离出的细菌种类的抗菌活性。除壁氏博德特氏菌和琼氏假单胞菌外，啤酒花β-酸浓度对所研究的细菌有显著影响。除地衣芽孢杆菌AUMC B - 550外，所有细菌均受到KEBOCID 310浓度的显著影响。然而，膝状寡养单胞菌对20 ppm的KEBOCID 310有负面反应。对于所研究的菌株，40 ppm和60 ppm的KEBOCID 310的效果几乎相同。除了更好地控制浓汁的固形物含量和储存温度外，识别细菌感染的来源和类型有助于管理该过程并减少浓汁变质。制糖行业的设计师可能会从本研究对炎热温度区域经济高效储存的理想条件的阐释中受益。
