Thermal Inactivation of Type E Botulinum Toxin

Abstract

The theoretical required cooking times for inactivation of type E Clostridium botulinum toxin (5,000 ld 50 mouse units per 0.5 ml) in haddock fillets of various sizes were calculated by graphical integration of the toxin inactivation rate and heat penetration data. The results indicated that normal cooking procedures should suffice to inactivate this amount of toxin. This conclusion was substantiated by the following additional experimental observations which revealed that the original experiments had been conducted under conservative conditions. First, maximal heat stability of the toxin was found to occur at about p H 5.5, with decreasing resistance upon increasing p H. The theoretical cooking times were based on destruction of the toxin at p H 6.7. The p H of radio-pasteurized inoculated haddock, when toxin production had occurred, was on the alkaline side, at which condition the toxin is heat-labile. Second, when spoilage was discernible in radio-pasteurized inoculated haddock, the toxin titer was low, about 50 ld 50 mouse units per 0.5 ml. Third, the toxin was adequately inactivated in toxic fillets after deep-fat frying for 3 min at 375 F (190.6 C) or after pan frying for 5 min per side at 400 F (204.4 C). Fourth, in this study, residual toxin activity was assayed by intraperitoneal injection of mice. It was shown that the oral toxic dose was 50 to 100 times greater than the intraperitoneal toxic dose.

Guidance on date marking and related food information: part 1 (date marking)

“…The pathogen is relevant for chilled foods under reduced oxygen packaging (ROP), in particular foods of the RePFED category that have not been processed to eliminate the spores (see Section 3.2.1.2) or the physico‐chemical characteristics do not inhibit their growth (see Section 3.2.2) (Notermans et al., 1990; Peck, 1997; FSA 2017). Compared to other bacterial toxins, those of non‐proteolytic C. botulinum can be heat inactivated by normal food cooking procedures (Licciardello et al., 1967; Wachnicka et al., 2016).…”

Botulinum Toxin in Dentistry

“…Botulism toxins are exotoxins produced by anaerobic, Gram-positive, rod-shaped, motile bacteria of the genus Clostridium, which is called Clostridium botulinum, C. butyricum, C. baratii and C. argentinense [1], which are widely distributed in the surrounding environment, including the soil and dust. Also, some food products such as honey, canned and not well cooked food may contain amounts of these bacteria [2]. These bacteria are divided into four distinct phenotypic groups (I-IV) and is also classified into seven serotypes (A-G) B has approval under the brand name Myobloc ® and Neurobloc ® .…”