Meat Processing Methods to Kill Trichinella Larvae

 

Several factors may affect the effectiveness of a set of conditions in larval inactivation. A temperature must be achieved throughout the meat, which takes longer with larger pieces. Most government regulations involve the addition of a considerable safety margin.

 

Cooking

 

Trichinella spiralis larvae may be killed:

(1) in 47 minutes at 52°C

(2) in 6 minutes at 55°C

(3) in less than 1 minute at 60°C

 

US Department of Agriculture Code of Federal Regulation times

 

Temperature	Time Required
52.2°C	2 hours
55.6°C	15 minutes
60°C	1 minute

 

A meat thermometer should be used to document internal temperatures achieved.

 

Microwave cooking may not give even heating throughout the meat and may be ineffective alone in larval inactivation unless longer times are used.

 

Freezing

 

Trichinella spiralis larvea may be killed:

(1) immediately at -23.3°C

(2) in 8 minutes at -20°C

(3) in 64 minutes at -15°C

(4) in 4 days at -10°C

 

US Department of Agriculture Code of Federal Regulation times

 

Temperature	Time Required
-17.8°C	106 hours
-20.6°C	82 hours
-23.3°C	63 hours
-26.1°C	48 hours
-28.9°C	35 hours
-31.7°C	22 hours
-34.5°C	8 hours
-37.2	0.5 hours

 

time required in hours =

= (0.12878 * ((temperature in °C)^2) + (12.42 * (temperature in °C)) + 284.596

 

Trichinella nativa is a species that may remain viable after freezing for months or years. This may be a problem for preparation of wild game.

 

Other Methods

 

Smoking, salting and curing:

(1) Techniques vary in effectiveness to inactivate larvae.

(2) Some methods may fail to inactivate larvae.

(3) Practices must conform with published regulations (US Department of Agriculture, Code of Federal Regulations, Title 9, Chapter III, 318.10.

 

Irradiation: >= 30 krad Cesium 137 or other high energy X-ray source will inactivate larvae