Advertisement

Pet Food Processing / Pet Food Safety
On November 1, 2012

Validation of extrusion as killing step for E. faecium

The greatest reduction of E. faecium for the inoculation levels (about 5 log) in a carbohydrate-protein meal would occur at the temperature of 81.1uC and moisture content of 28.1%

Outbreaks of Salmonellosis and recalls of low-moisture foods including extruded products highlight the need for the food and feed industries to validate their extrusion processes to ensure the destruction of pathogenic microorganisms. Response surface methodology was employed to study the effect of moisture and temperature on inactivation by extrusion of Enterococcus faecium NRRL B-2354 in a carbohydrate-protein mix.

A balanced carbohydrate-protein mix was formulated to different combinations of moisture contents, ranging from 24.9% to 31.1%, and each was inoculated with a pure culture of E. faecium to a final level of 5 log CFU/g. Each mix of various moistures was then extruded in a pilot scale extruder at different temperatures (ranging from 67.5 to 85 degrees C). After the extruder was allowed to equilibrate for 10 minutes, samples were collected in sterile bags, cooled in dry ice and stored at 4 degrees C prior to analysis.

E. faecium was enumerated with tryptic soy agar and membrane Enterococcus media, followed by incubation at 35 degrees C for 48 h. Each extrusion was repeated twice, with the central point of the design being repeated four times. From each extrusion, three subsamples were collected for microbial counts and moisture determination.

According to the response surface analysis, the greatest reduction of E. faecium for the inoculation levels studied here (about 5 log) in a carbohydrate-protein meal would occur at the temperature of 81.1 degrees C and moisture content of 28.1%.

Source : A. Bianchini et al., 2012. Validation of extrusion as a killing step for Enterococcus faecium in a balanced carbohydrate-protein meal by using a response surface design. J Food Prot 75: 1646–1653. doi:10.4315/0362-028X.JFP-12-085

Comments powered by Disqus

Advertisement

Petfood Forum China

Advertisement

Advertisement

Read the June issue of Petfood Industry!

June 2015

The June 2015 issue of Petfood Industry profiles the family owned company, CANIDAE, and how it has succeeded in carving a niche in the pet specialty market. The company believes educating retailers about its products and focusing on consumers' needs are keys to maintaining their spot in the market. Plus, learn how pet food manufacturers can use their product’s packaging as a way of branding to attract customers and why companies are eyeing Poland for market expansion opportunities.

READ MORE in Petfood Industry magazine

Advertisement