Characterization of spoilage markers in modified atmosphere packaged iceberg lettuce.
Int J Food Microbiol
; 279: 1-13, 2018 Aug 20.
Article
em En
| MEDLINE
| ID: mdl-29715602
ABSTRACT
Fresh cut iceberg lettuce spoilage was studied considering the microbial and biochemical activity, the formation of volatile organic compounds (VOC) and consumer acceptability. Lettuce was packaged under three different packaging conditions and stored at 4⯰C for 10â¯days anaerobic packaging (ANAER), equilibrium modified atmosphere packaging with 3% O2 (EMAP) and perforated packages (AIR). Results indicated a clear distinction between packaging conditions. EMAP and AIR resulted in a short shelf life (≤5.6â¯days) which was limited due to browning, leading to consumer rejection as assessed via the Weibull hazard analysis method, while no off-odors were detected. Culture- independent 16â¯s rRNA gene amplicon sequencing revealed Pseudomonas spp. as the dominating species. In contrast, under ANAER conditions, lactic acid bacteria dominated with genera of Leuconostoc spp. and Lactococcus spp. proliferating, while also oligotypes of Pseudomonas spp. were found. Spoilage under ANAER occurred after 6.6â¯days and it was related to strong fermentative-like off-odors that were present by the end of storage. As revealed by selective ion flow tube mass spectrometry (SIFT-MS), these odors were associated with several VOCs such as ethanol, 3-methyl-1-butanol, 2,3-butanediol, (Z)-3-hexen-1-ol, hexanal, acetic acid, ethyl acetate and dimethyl sulfide. Panelists rejected the iceberg lettuce due to the formation of off-odors while the overall appearance remained good throughout the study. Hence a sensor based technology incorporated in the packaging, detecting VOCs and in particular ethanol as dominant compound, could serve as a spoilage indicator for ANAER packed lettuce, which proved to have the longest shelf life.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Embalagem de Alimentos
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Lactuca
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Compostos Orgânicos Voláteis
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Microbiologia de Alimentos
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Conservação de Alimentos
Idioma:
En
Revista:
Int J Food Microbiol
Assunto da revista:
CIENCIAS DA NUTRICAO
/
MICROBIOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article