ABSTRACT
In this study, the effect of chitosan coating containing emulsion and nanoemulsion of Hyssopus officinalis essential oil (EO) on the chemical, microbiological and sensory characteristics of shrimp (Litopenaeus vannamei) was investigated. The minimum value of TVB-N (Total volatile basic nitrogen), TBARS (Thiobarbituric acid reactive substances), PV (peroxide value), TMA-N (Trimethylamine-nitrogen) and FFA (Free fatty acids) after 12 days were shown in NE + HEO 1% (coating containing chitosan with nanoemulsion of EO) with 20.53 mg N/100 g, 0.5 µg/kg, 0.88 MAQ peroxide/kg, 1.3 mg/100 g and 12.16 mg 100% of oleic acid, respectively. Also, minimum value of pH after 12 days was related to the CE + HEO 1% (coating containing chitosan with emulsion of EO) with 7.60. The minimum value of psychrophilic and mesophilic microbial count after 12 days were shown in NE + HEO 1%, 4.40 ± 0.36 and 4.03 ± 0.06 cfu/g, respectively. The best score of sensory evaluation was observed in the NE-HEO 1% treatment. As a result, the edible coating containing chitosan-based nanoemulsion could be effective to the preservation of shrimp's microbiological, chemical, and sensory characteristics.
ABSTRACT
Polychlorinated biphenyls (PCBs) are harmful chemicals that are persistent in the environment and can accumulate in the food chain. The purpose of the present research was to assess non-dioxin-like polychlorinated biphenyls (NDL-PCBs) in some dairy products (yogurt, doogh, and kashk) using modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) technique and gas chromatography-triple-quadrupole mass spectrometry (GC-QqQ-MS/MS) method and risk assessment study. The LOQs (limit of quantifications), LODs (limit of detections), recovery, and RSD for the PCB analytes were 0.180-0.360, 0.06-0.12 ng/g fat, 97.45-102.63%, and 6.33-8.86%, respectively. The results revealed that the mean concentrations of Æ©6-NDL-PCBs in samples were 15.17 ± 3.44 ng/g fat, which was lower than the standard level established by European Union (EU, 40 ng/g fat). The maximum mean level was PCB 180 (9.98 ± 2.04 ng/g fat) and the minimum mean level of PCBs in samples was PCB 28 (0.09 ± 0.06 ng/g fat). Also, results showed that kashk samples had a maximum mean level of 6-NDL-PCBs (18.66 ± 2.42 ng/g fat) and doogh samples had a minimum mean level of 6-NDL-PCBs (12.21 ± 2.22 ng/g fat). The mean level of 6-NDL-PCBs in yogurt samples was 14.65 ± 2.02 ng/g fat. The heat map results showed the correlation between the spectral indices of 6-NDL-PCBs in different dairy products. According to the Monte Carlo method, risk assessment was done using calculating the Estimated Daily Intake (EDI) and Incremental Life Cancer Risk (ILCR). The EDI values of 6 NDL-PCBs based on the 95th percentile in yogurt, doogh, and kashk were 14.3, 1.49, and 0.5 ng/kg.day, respectively. Considering that the contaminant level in the samples is lower than the EU limit, it can be concluded that dietary exposure to 6 NDL-PCBs may not pose a risk to the health of consumers.
ABSTRACT
The objective of the present study was to investigate the level of 16 PAHs in fruit juice samples (orange, apple, peach, pineapple, and mango) with three different packages (PET bottle, Tetra Pak, and canned packaging) by using MSPE/GC-MS (magnetic solid-phase extraction and gas chromatography-mass spectrometry) method. In this method limit of detection (LOD), and limit of quantitation (LOQ), and recovery were 0.030-0.280 µg/L, 0.090-0.840 µg/L, and 94.8-102%, respectively. Our results showed the median of total PAHs and PAH4 (in all samples) were 7.67 ± 3.19 and 0.370 ± 0.160 µg/L, respectively. The median of BaP in samples was )0.060 ± 0.030 µg/L( lower than the standard level (0.200 µg/L in drinking water) of US Environmental Protection Agency (USEPA). Also, our results showed that pineapple juice had a maximum median of total PAHs of 12.4 ± 4.84 µg/L and mango juice had a minimum median of total PAHs of 5.17 ± 1.24 µg/L. Additionally, canned packaging had a maximum average total PAHs of 10.6 ± 5.22 µg/L and PET bottles had a minimum average total PAH of 5.25 ± 2.03 µg/L. A heat map approach was also used to cluster samples. The Monte Carlo results indicated that the estimated daily intake (EDI) rank order was Na > B(g)P > Ch > I(cd)P > B(b)F > Ph > B(k)F > F > Ace > Fl > B(a)P > B(a)A > P >A. The Monte Carlo simulation (MCS) results showed the incremental lifetime cancer risk (ILCR) at the 95th percentiles for adults and children was 4.91 × 10-7 and 9.12 × 10-7, respectively. It is concluded that the concentration of PAHs compounds in Iranian fruit juices is lower than the existing standards, and in terms of the risk of carcinogenesis, it does not threaten the human health (< 10-6).
