Acrylamide Production in Autoclaved Rodent Feed.

Area of Science:

• Animal Nutrition
• Food Science
• Toxicology

Background:

• Steam autoclaving is a common method for sterilizing rodent feed.
• High temperatures and pressures during autoclaving can negatively impact diet quality.
• Potential chemical changes and their biological effects require careful consideration.

Purpose of the Study:

• To evaluate physical and chemical alterations in rodent feed after autoclaving at various temperatures.
• To assess the impact of autoclaved rodent diets on mouse health and physiology.
• To compare autoclaved feed with irradiated feed regarding nutritional quality and safety.

Main Methods:

• NIH31 rodent feed was autoclaved at 230, 250, 260, and 270 °F.
• Feed pellet hardness and acrylamide concentration were measured.
• Mice were fed study diets for 28 days; tissue and urine samples were analyzed for acrylamide, glycidamide, and genotoxicity.

Main Results:

• Feed pellet hardness and acrylamide concentration increased with higher autoclaving temperatures.
• Plasma acrylamide and glycidamide were elevated at 270 °F; urine metabolites were elevated in most autoclaved diets.
• Liver DNA adducts, indicating genotoxicity, were significantly higher in all autoclaved diets compared to irradiated feed.

Conclusions:

• Autoclaving rodent feed, particularly at higher temperatures, increases acrylamide formation and genotoxicity.
• These chemical changes in feed can affect animal models, even without impacting feed intake or body weight.
• Research institutions must carefully select autoclaving temperatures and consider the implications for study outcomes.