|MIKS-KRAJNIK, MARTA - Warmia And Mazury University|
|YOON, YONG-JIN - Nanyang Technological University|
|YUK, HYUN-GYUN - National University Of Singapore|
Submitted to: Food Microbiology and Safety Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/20/2016
Publication Date: 6/28/2016
Citation: Miks-Krajnik, M., Yoon, Y., Ukuku, D.O., Yuk, H. 2016. Growth dynamics of specific spoilage organisms and associated spoilage biomarkers in chicken breast stored aerobically. Food Microbiology and Safety Journal. DOI:10.1111/1750-3841.13371.
Interpretive Summary: The growth dynamics of total viable count (TVC) and six specific spoilage organisms (SSOs) including, psychrotrophs, Pseudomonas spp., lactic acid bacteria, Brochothrix thermospacta and H2S producing bacteria in spoiled chicken breast were estimated and specific volatile biomarkers associated with each bacterium was identified using solid phase microextraction (SPME) assay in combination with a gas chromatography-mass spectrometry-flame ionization detector (GC-MS/FID). Pseudomonas spp. was the dominant SSO, while B. thermospacta had the highest maximum growth. Among the 27 volatile organic acids compounds (VOCs) identified by GC-MS/FID, ethanol (EtOH), 1-butanol-3-methyl (1But3M) and acetic acid were the highest, while VOCs production associated with coliforms and H2S-producing bacteria was less. Therefore presence of EtOH, 1But3M and acetic acid in spoiled chicken breast can be used as volatile spoilage biomarkers for rapid evaluation of poultry quality by SPME-GC-MS/FID.
Technical Abstract: This study was performed to identify and quantify selected volatile spoilage biomarkers in a headspace over chicken breast using solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry-flame ionization detectors (GC-MS/FID). The chicken breast samples were aerobically stored at 4, 10 and 21 deg C. The shelf life of chicken breast was estimated based on TVC and Pseudomonas spp. counts. The growth dynamics of total viable count (TVC) and six specific spoilage organisms (SSOs) including, psychrotrophs, Pseudomonas spp., lactic acid bacteria, Brochothrix thermospacta and H2S producing bacteria were determined using Gompertz-fitted growth curves including characterization of maximum growth rates, maximum level (M) values and spoilage (S) values at two minimal spoilage levels. Pseudomonas spp. was the dominant SSO, while B. thermospacta had the highest maximum growth rates. Among the 27 volatile organic acids compounds (VOCs) identified by GC-MS in spoiled chicken samples, ethanol (EtOH), 1-butanol-3-methyl (1But3M) and acetic acid (C2) achieved the highest Pearson correlation coefficients of 0.658, 0.615 and 0.593, respectively, with TVC, regardless of storage temperature. Partial least squares (PLS) regression revealed that synthesis of 1But3M and C2 were most likely induced by the metabolic activity of B. thermospacta and lactic acid bacteria, while coliforms and H2S-producing bacteria had lesser impact on VOCs production. The increase in content of selected volatile spoilage biomarkers (EtOH, 1But3M, C2) in the headspace of spoiled chicken breast was found to be statistically significant (P < 0.05) with TVC growth. These findings highlight the possibility of using these selected spoilage biomarkers: EtOH, 1But3M and C2 for rapid evaluation of poultry quality by SPME-GC-MS.