MICROBIOLOGICAL MONITORING OF ASEPTICALLY PACKED SEMIFLUID FOODS WITHPH GREATER-THAN-4.5 (LOW ACID PRODUCTS)

Sauce a la Carbonara and Sauce Hollandaise serving as a model for low acid aseptic products were inoculated with salmonellae, S. aureus, C. sporogenes, C. perfringens as well as with moulds and bacteria that we re isolated from the air of an aseptic filling and packaging chamber. Formation of blowers and growth of the inocula were registered. Follow ing three weeks' storage at 20-22 degrees C, only a limited number of packs showed swelling and detectable organoleptic changes of the produ ct itself whereas the rest of them always remained unaltered. Neverthe less, the pathogenic bacteria multiplied strongly. S. aureus despite o f intense multiplication, produced no swelling at all. From the experi mental conditions choosen here and for the products used in this study it can be concluded that total sampling is the only non destructive t est of concern. The packages have to be held in quarantine for 3 weeks at 22 degrees C or 5 weeks at 15 degrees C respectively, and may not be released unless each pack is inspected individually.