Time evolution of microbiological quality and content of volatile compounds in chicken fillets packed using various techniques and stored under different conditions.

The aim of this study was to evaluate dependence of microbiological quality of chicken fillets and profile of volatile compounds in their packages on the applied packaging technique and storage conditions. Samples packaged in either normal atmosphere (AP, air packaging, PVC overwrap), in modified atmosphere with high oxygen content (Hi-O2-MAP), or in vacuum (VP) were stored in a cold room or exposed in a display case for 8 days. Quality of the meat was determined on day 1, 3, 6, 7, and 8 of the storage or exposition time. The microbiological quality of chicken fillets was assessed by determining the number of mesophilic aerobic bacteria, lactic acid bacteria, Pseudomonas spp. bacteria, and Enterobacteriaceae family bacteria. The profile of volatile compounds in the packaging of chicken fillets was also determined. At the beginning of the storage, bacteria of all major groups were growing at similar rates regardless of the used packaging technique. However, at the end of the period, the growth dynamic was diversified. The profile of the volatile compounds did not depend on the storage or exposition time regardless of the storage conditions and/or the packaging technique. The results of this study indicate that there is a potential to gain understanding of spoilage of packed chicken meat through the analysis of volatile compounds in association with microbiological analysis. However, future research should be based on standardized material with similar bacterial load.

Influence of storage and packaging method on chicken breast meat chemical composition and fat oxidation.

The aim of this study was to determine the influence of storage conditions and packaging methods on chicken breast meat chemical composition and fat oxidation. In this study, chicken breasts available in retail sale were used for evaluation. The meat packed by three different methods (air packaging-AP, modified atmosphere packaging-MAP, and vacuum packaging-VP) was stored in a cooling room or a commercial display case for 9 D and tested for basic chemical composition, lipid oxidation (TBARS), and fatty acid composition. Meat in MAP during storage in the cooling room was characterized by higher (P ≤ 0.05) TBARS values as compared to meat packaged in AP and VP, respectively. The highest share in the fatty acid profile in chicken breasts was demonstrated by monounsaturated fatty acid, including cis C18:1 (n9 + n11) acid in the range from 31.86 to 34.66%. A high share of polyunsaturated acids was observed, including linoleic (C18:2 cis, cis) acid from 24.50 to 31.22% of all fatty acids. The simple relationship between the changes in the profile of fatty acids in meat packaged using different methods and in storage time was not determined, likely due to the variability of the composition of fatty acids in chicken breasts depending on the sample and the general low level of fat found in the meat.

Seasonal and geographical variations in levels of polychlorinated biphenyls (PCB) and polybrominated diphenyl ethers (PBDE) in Polish butter fat used as an indicator of environmental contamination.

The aim of this study was to evaluate the seasonal variation/geographical distribution of environmental concentration of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) across Poland using butter fat as an indicator of the contaminants. The average concentration of six indicator PCBs determined in the studied samples was 1500 pg g(-1) fat. The average concentration of 12 dioxin-like PCBs expressed as lower-bound dioxin-equivalent toxicity was 0.684 pg TEQ g(-1) fat. The average total concentration of 14 investigated PBDE congeners was 105 pg g(-1) fat. Statistically significant concentration differences between summer and winter samples were found. The results of this study indicate also a significant geographical diversification of butter contamination reflecting regional differences in environmental contamination. The seasonal variation of PBDE profiles evidences transformation of PBDE within the environment.

PAHs, PCBs, PBDEs and Pesticides in Cold-Pressed Vegetable Oils.

The aim of this study was to investigate levels of polychlorinated biphenyls (marker and dioxin-like congeners), polycyclic aromatic hydrocarbons (EPA 15 + 1), polybrominated diphenyl ethers (14 predominant congeners) and pesticides (74 compounds) in various cold-pressed vegetable oils. Poppy seed oil, rapeseed oil, sesame seed oil, pumpkinseed oil, hempseed oil, linaire oil, borage oil and evening star oil were investigated. Results of this study revealed that concentrations of PCBs, PBDEs and PAHs were low in majority of the investigated samples. However, high concentrations of organophosphorus insecticides were found. Chlorpyrifos methyl and pirimiphos methyl were the pesticide residues most commonly found in the studied oils. Concentration of 15 + 1 EPA PAHs was within the 17.85-37.16 µg kg(-1) range, concentration of (marker) PCBs varied from 127 to 24,882 pg g(-1), dioxin-like TEQ values were below 0.1 pg TEQ g(-1). Concentration of PBDEs was below LOQ in most cases.

Non-dioxin-like and dioxin-like polychlorinated biphenyls in butter sampled from the Polish retail market.

The aim was to investigate levels of polychlorinated biphenyls (PCBs) in butter available on the Polish retail market. A gas chromatography-based method was developed for the purpose of this study. An ion-trap mass spectrometer was used as a detection system with high-resolution chromatography. Recoveries of individual PCBs from spiked samples varied from 58% to 105% with a recovery relative standard deviation in the range 3-16%. Levels of eight non-dioxin-like and twelve dioxin-like congeners were determined. Toxic equivalent factors (TEQs) were calculated using World Health Organization (WHO) TEQs. The average concentration of the sum of six PCBs (28, 52, 101, 138, 153, and 180) was found to be 1561±728 pg g(-1) (fat) and the upper-bound concentrations of dioxin-like congeners were (1 standard deviation uncertainty) 0.441±0.384 pg PCB-TEQ g(-1) (fat).