当前位置： SCI文献检索 > APPLIED AND ENVIRONMENTAL MICROBIOLOGY期刊下所有文献 > Mesophilic and psychrotrophic bacteria from meat and their spoilage potential in vitro and in beef.

Mesophilic and psychrotrophic bacteria from meat and their spoilage potential in vitro and in beef.

Abstract：

:Mesophilic and psychrotrophic populations from refrigerated meat were identified in this study, and the spoilage potential of microbial isolates in packaged beef was evaluated by analyzing the release of volatile organic compounds (VOC) by gas chromatography-mass spectrometry (GC/MS). Fifty mesophilic and twenty-nine psychrotrophic isolates were analyzed by random amplified polymorphic DNA-PCR, and representative strains were identified by 16S rRNA gene sequencing. Carnobacterium maltaromaticum and C. divergens were the species most frequently found in both mesophilic and psychrotrophic populations. Acinetobacter baumannii, Buttiauxella spp. and Serratia spp. were identified among the mesophilic isolates, while Pseudomonas spp. were commonly identified among the psychrotrophs. The isolates were further characterized for their growth at different temperatures and their proteolytic activity in vitro on meat proteins extracts at 7 degrees C. Selected proteolytic strains of Serratia proteamaculans, Pseudomonas fragi, and C. maltaromaticum were used to examine their spoilage potential in situ. Single strains of these species and mixtures of these strains were used to contaminate beef chops that were packed and stored at 7 degrees C. At time intervals up to 1 month, viable counts were determined, and VOC were identified by GC/MS. Generally, the VOC concentrations went to increase during the storage of the contaminated meats, and the profiles of the analyzed meat changed dramatically depending on the contaminating microbial species. About 100 volatiles were identified in the different contaminated samples. Among the detected volatiles, some specific molecules were identified only when the meat was contaminated by a specific microbial species. Compounds such as 2-ethyl-1-hexanol, 2-buten-1-ol, 2-hexyl-1-octanol, 2-nonanone, and 2-ethylhexanal were detectable only for C. maltaromaticum, which also produced the highest number of aldehydes, lactones, and sulfur compounds. The highest number of alcohols and ketons were detected in the headspace of meat samples contaminated by P. fragi, whereas the highest concentrations of some alcohols, such as 1-octen-3-ol, and some esters, such as isoamyl acetate, were produced by S. proteamaculans. In conclusion, different microbial species can contribute to meat spoilage with release of different volatile compounds that concur to the overall quality decrease of spoiling meat.

journal_name

Appl Environ Microbiol

journal_title

Applied and environmental microbiology

authors

Ercolini D,Russo F,Nasi A,Ferranti P,Villani F

doi

10.1128/AEM.02762-08

subject

Has Abstract

pub_date

2009-04-01 00:00:00

pages

1990-2001

issue

eissn

0099-2240

issn

1098-5336

pii

AEM.02762-08

journal_volume

pub_type

杂志文章

在线工具

Mesophilic and psychrotrophic bacteria from meat and their spoilage potential in vitro and in beef.