High pressure inactivation of Clostridium botulinum type E endospores in model emulsion systems

Clostridium botulinum type E is a cold-tolerant, neurotoxigenic, endospore-forming organism, primarily associated with aquatic environments. High pressure thermal (HPT) processing presents a promising tool to enhance food safety and stability. The effect of fat on HPT inactivation of C. botulinum type E spores was investigated using an emulsion model system. The distribution of spores in oil-in-water (O/W) emulsions and their HPT (300-750 MPa, 45-75 degrees C, 10 min) inactivation was determined as a function of emulsion fat content (30-70% (v/v) soybean oil in buffer). Approximately 26% and 74% of the spores were located at the oil-buffer interface and the continuous phase, respectively. Spore inactivation in emulsion systems decreased with increasing oil contents, which suggests that the fat content of food plays an important role in the protection of C. botulinum type E endospores against HPT treatments. These results can be helpful for future safety considerations.