Frozen Beef Contamination after Exposure to Low Levels of Ammonia Gas

Abstract

Regulations and publications about food contaminated during ammonia refrigerant leaks provide limited information and recommendations, which means that contaminated products are often held for an indeterminate period or condemned. Moreover, the scientific literature offers little guidance on disposing of products exposed to low levels of ammonia refrigerant gas. We evaluated meat contaminated with low levels of ammonia under frozen storage conditions. Fresh beef semitendinosus muscles were trimmed of external fat; fabricated into 10 x 5 x 2.3 cm (height x width x depth) steaks; and exposed to 50, 100, 250, and 500 ppm ammonia gas (85 mL/min) in a plexiglass enclosure contained in a freezer for 6, 12, 24, and 48 h at -17 +/- 3 degrees C. Ammonia content in meat was analyzed by the indophenol method, and pH was measured according to AOAC official method 981.12. Ammonia levels and pH values increased significantly (P < 0.05) in the exposed meat with increasing exposure times and ammonia concentrations. Ammonia levels were 34.2, 51.5, 81.1, and 116 ppm, and pH values ranged from 5.56 to 5.75 (control range 5.31 to 5.43) when the meat was exposed to 50, 100, 250, 500 ppm for 48 h. Our results showed that meat ammonia content was low even with ammonia exposures as high as 500 ppm at freezing temperatures.

Ammonia Gas Permeability of Meat Packaging Materials

“…The treatment chamber was a Plexiglas box measuring 38 × 13.5 × 36 cm (width × depth × height; volume 18.5 L) and was previously described by Karim and others (2010). The exposure chamber was tested for leaks and proper seal by pressurizing with air, locking, and immersing in a water bath.…”

“…The exposure system as illustrated in Karim and others (2010) was designed to simulate realistic conditions of low‐level of ammonia exposure and allowed for manual control of the ammonia flow rate entering the chamber, and maintaining a desired level of ammonia concentration. The ammonia cylinder was connected to a 0 to 65 mm gas flow regulator inlet (Cole‐Parmer Instrument Co., Vernon Hills, Ill., U.S.A.), and the gas flow regulator outlet was fitted to a T‐shaped plastic connector.…”

A sensor probe for the continuous in situ monitoring of ammonia leakage in secondary refrigerant systems

“…As a consequence, there is some potential for leakage and contamination into the secondary system, 6,7 with potential hazards of human exposure or contamination of refrigerator contents. 8,9 Toxic effects can be observed at concentrations from 100 ppm. Levels between 100 and 200 ppm can cause eye irritation and exposure to levels of 400 to 1700 ppm may lead to irritation of the airways and coughing.…”

Hardware Engineering of Hazardous Gas and Alcoholic Substances Detector in Meat Using Microcontroller and Gas Sensor

“…Ammonia, a food contaminant regulated in many countries, could not be found in all types of grilled meat in the research. According to Karim et al [46], the ammonia content of frozen meat was found to be low even after high exposures. Therefore, the proposed prototype design could actually detect ammonia gas substances in grilled meat, but the grilled meat was not contaminated with ammonia gas substances.…”