Occurrence of Some Spoilage Microorganisms in Cheese Highlighting The Impact of Salt and Starter Culture Activity on The Viability of Pseudomonas aeruginosa and Candida albicans

Ahmed, Lamiaa; Taher, Eman M; Fahim, Karima M; Ali, Zeinab

doi:10.21608/ejvs.2025.315453.2361

Occurrence of Some Spoilage Microorganisms in Cheese Highlighting The Impact of Salt and Starter Culture Activity on The Viability of Pseudomonas aeruginosa and Candida albicans

Articles in Press

Document Type : Original Article

Authors

¹ Department of food hygiene and control, faculty of veterinary medicine, Cairo university. Giza. Egypt

² Lecturer, food hygiene and control Department. faculty of veterinary medicine, Cairo university

³ Food Hygiene and Control, Faculty of Veterinary Medicine, Cairo University, Egypt

10.21608/ejvs.2025.315453.2361

Abstract

Cheese contamination
with spoilage microorganisms causes significant economic losses in food industry. In this study, 100 cheese verities (Kariesh, Domiatti, Ras, and Processed (25 each)) were gathered from different markets across Cairo governorate, Egypt. Chemical assessment (Salt% and Titratable acidity) and Microbiological evaluation (Total yeast, Mold, Lipolytic, and Proteolytic counts) were done. The results found that both Kariesh and Domiatti cheeses showed high incidence of yeast that reached 2.6 × 10¹⁰ and 4.7 × 10¹⁰ cfu/g, respectively. Moreover, Kariesh and Ras cheeses exhibited the highest proteolytic and lipolytic counts, nevertheless, Kariesh cheese had the highest mold count with mean value of 4.6 × 10⁸ cfu/g. The second part of the study studied the effect of salt percentage and starter culture activity represented in its produced acidity on viability of Pseudomonas aeruginosa 27853 and Candida albicans during the cold storage of lab-manufactured fresh and ripened white soft cheeses. The obtained results demonstrated that P. aeruginosa could not be detected in fresh or ripened soft cheese by the end of the sixth and third weeks of storage period, respectively. While C. albicans continued to grow in both fresh and ripened soft cheese samples until visible deterioration appeared (holes and yeasty flavor) by the ninth week. In contrast to C. albicans, the study's findings revealed that P. aeruginosa could be efficiently controlled by a combination of salt and acidity presenting a safe and feasible approach for spoilage control in cheese sector.

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