Premium
Resuscitation of acid‐injured Salmonella in enrichment broth, in apple juice and on the surfaces of fresh‐cut cucumber and apple *
Author(s) -
Liao C.H.,
Fett W.F.
Publication year - 2005
Publication title -
letters in applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.698
H-Index - 110
eISSN - 1472-765X
pISSN - 0266-8254
DOI - 10.1111/j.1472-765x.2005.01794.x
Subject(s) - agar , food science , salmonella , salmonella enterica , acetic acid , chemistry , biology , microbiology and biotechnology , bacteria , biochemistry , genetics
Aims: To investigate the resuscitation of acid‐injured Salmonella enterica in selected enrichment broths, in apple juice and on cut surfaces of apple and cucumber slices. Methods and Results: Following exposure to 2·4% acetic acid for 7 min, S. enterica (serovars Mbandaka, Chester and Newport) cells were used to inoculate enrichment broths, phosphate‐buffered saline (PBS), apple juice and fruit slices. Injured Salmonella cells resuscitated and regained the ability to form colonies on selective agar (Xylose‐Lysine‐Tergitol ® 4) if they were incubated in lactose broth (LB), universal pre‐enrichment broth (UPB) or buffered peptone water (BPW), but not in tetrathionate broth, PBS or apple juice. The resuscitation occurred at a significantly ( P > 0·05) faster rate in UPB than in LB or BPW. The resuscitation also occurred on the surfaces of fresh‐cut cucumber at 20°C, but not at 4°C. Conclusions: Acid‐injured Salmonella cells resuscitated in nonselective enrichment broths at different rates, but not in selective enrichment broth, apple juice, PBS or on fresh‐cut apple. Significance and Impact of the Study: Pre‐enrichment of food samples in UPB prior to selective enrichment is recommended. Injured Salmonella cells have the ability to resuscitate on fresh‐cut surfaces of cucumber when stored at abusive temperatures.