Spoilage of vacuum‐packed beef by a clostridium sp

Abstract

An unusual spoilage condition of chill-stored normal pH vacuum-packed beef characterised by gross distension (blowing) of the packs and of-odours perceived on initial opening of the packs as 'sulphurous' and subsequently as yuity', 'solvent-like' and 'strong cheese' has been chemically defined. Hydrogen and carbon dioxide were the major components of the headspace gases. Other components included hydrogen sulphide, methanethiol, dimethyl sulphide, dimethyl di-and trisulphides, methylthioacetate, 1-butanol, acetic and butanoic acids, and 1-butyl esters of a range of C,-C6 fatty acids. Published sensory data are consistent with components of this mixture being responsible for the off-odours detected. When grown in pure culture on beef under identical storage conditions, a Clostridium sp isolated from one of the blown packs produced the same chemical and sensory spoilage characteristics.

Clostridium gasigenes sp. nov., a psychrophile causing spoilage of vacuum-packed meat.

“…Psychrotolerant clostridia have been associated with instances of chilled meat spoilage where initial microbiological examination failed to detect a causative micro-organism. Difficulties with the isolation of the causative clostridia have been reported (Dainty et al, 1989 ;Kalchayanand et al, 1989 ;Broda et al, 1996). It has been suggested, therefore, that the composition of headspace volatiles from ' blown packs ', as analysed by GC and MS, may indicate the bacterial species likely to be involved in the spoilage, prior to lengthy and unreliable isolation of causative psychrotolerant clostridia (Dainty et al, 1989 ;Broda et al, 1996).…”

“…Difficulties with the isolation of the causative clostridia have been reported (Dainty et al, 1989 ;Kalchayanand et al, 1989 ;Broda et al, 1996). It has been suggested, therefore, that the composition of headspace volatiles from ' blown packs ', as analysed by GC and MS, may indicate the bacterial species likely to be involved in the spoilage, prior to lengthy and unreliable isolation of causative psychrotolerant clostridia (Dainty et al, 1989 ;Broda et al, 1996). Butanol, butyric acid, carbon dioxide and hydrogen are products of the butyric-type fermentative metabolism typical of mesophilic, saccharolytic clostridia (Jones & Woods, 1986, 1989.…”

“…It has been suggested, therefore, that the composition of headspace volatiles from ' blown packs ', as analysed by GC and MS, may indicate the bacterial species likely to be involved in the spoilage, prior to lengthy and unreliable isolation of causative psychrotolerant clostridia (Dainty et al, 1989 ;Broda et al, 1996). Butanol, butyric acid, carbon dioxide and hydrogen are products of the butyric-type fermentative metabolism typical of mesophilic, saccharolytic clostridia (Jones & Woods, 1986, 1989. Similar products with a unique range of butyl esters were found in the headspaces of both naturally spoiled vacuum packs and those artificially contaminated by psychrophilic C. estertheticum (Dainty et al, 1989), and also in packs naturally spoiled by other psychrotolerant clostridia (Broda et al, 1996).…”

“…† With packs inoculated with pure cultures of strains DB1A T and R26 and with uninoculated control packs, 1-hexanol, 1-octen-3-ol, hexanal, benzaldehyde, ethyl butyrate, 1-butyl formate, 1-butyl propionate and oxygen were not detected and the presence of nitrogen was not determined ; these compounds, however, were present in vacuum packs inoculated with the pure culture of C. estertheticum (Dainty et al, 1989). ‡ Data from Dainty et al (1989) ; means of duplicate tests.…”

Abattoir sources of psychrophilic clostridia causing blown pack spoilage of vacuum-packed chilled meats determined by culture-based and molecular detection procedures

“…(Dainty et al 1989;Kalchayanand et al 1989;Broda et al 1996). Currently, it is believed that the frequency and severity of commercial incidents of blown pack spoilage could be minimized, among others, by removing the abattoir source(s) of psychrophilic clostridia and/or by limiting transfer of these clostridia from their abattoir source(s) onto carcasses.…”