El-Garhi Hosam-Eddin M, Abd-Elghany Ahmad A, Ibrahim Azza M A, El-Aidie Safaa A M, Castro-Muñoz Roberto
Dairy Science and Technology, Faculty of Agriculture, Fayoum University, Faiyum, Egypt.
Dairy Technology Department, Animal Production Research Institute, Agricultural Research Centre, Giza, Egypt.
Probiotics Antimicrob Proteins. 2025 Jul 2. doi: 10.1007/s12602-025-10622-2.
This study investigates the antimicrobial properties of lactic and acetic acids against both pathogenic and lactic acid bacteria (LAB), with a focus on their application in the direct acidification of raw milk for Cheddar cheese production. The acids effectively inhibited key pathogenic strains, including Salmonella Enteritidis, Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa, while largely preserving the viability of beneficial LAB (Lactobacillus acidophilus, Streptococcus thermophilus, Lactobacillus bulgaricus, and Lacticaseibacillus paracasei), except under highly acidic conditions. When used in cheese manufacturing, direct acidification with lactic (LRC) and acetic acids (ARC) enhanced microbial safety by eliminating pathogens and spoilage organisms and promoted biochemical changes associated with accelerated ripening. Treated cheeses showed increased levels of moisture, acidity, ripening indices, total viable counts, and LAB populations, though with slightly reduced protein and fat content. Sensory evaluation indicated comparable flavor among cheeses, with pasteurized cheese (PC) receiving the highest overall acceptability. These findings demonstrate that direct acidification using organic acids is a promising strategy for producing microbiologically safe raw milk Cheddar cheese with improved ripening potential. However, adjusting pH to 5.4 and optimizing ripening conditions are recommended to enhance sensory quality and consumer acceptance.
本研究调查了乳酸和乙酸对病原菌和乳酸菌（LAB）的抗菌特性，重点关注它们在切达干酪生产中原奶直接酸化中的应用。这些酸有效地抑制了关键病原菌，包括肠炎沙门氏菌、金黄色葡萄球菌、蜡样芽孢杆菌、大肠杆菌和铜绿假单胞菌，同时在很大程度上保持了有益乳酸菌（嗜酸乳杆菌、嗜热链球菌、保加利亚乳杆菌和副干酪乳杆菌）的活力，除了在高酸性条件下。在奶酪制造中使用时，乳酸（LRC）和乙酸（ARC）直接酸化通过消除病原体和腐败微生物提高了微生物安全性，并促进了与加速成熟相关的生化变化。经过处理的奶酪显示出水分、酸度、成熟指数、总活菌数和乳酸菌数量增加，不过蛋白质和脂肪含量略有降低。感官评价表明，奶酪之间的风味相当，巴氏杀菌奶酪（PC）的总体可接受性最高。这些发现表明，使用有机酸直接酸化是生产具有改善成熟潜力的微生物安全原奶切达干酪的一种有前景的策略。然而，建议将pH值调节至5.4并优化成熟条件，以提高感官质量和消费者接受度。
