Role of marination, natural antimicrobial compounds, and packaging on microbiota during storage of chicken tawook.

The aim of this study was to investigate the antimicrobial effect of marination, natural antimicrobials, and packaging on the microbial population of chicken tawook during storage at 4°C. Chicken meat was cut into 10 g cubes and marinated. The chicken was then mixed individually with 0.5% or 1% (w/v) vanillin (VA), ß-resorcylic acid (BR), or eugenol (EU), and stored under aerobic (AP) or vacuum (VP) packing at 4°C for 7 d. The marinade decreased microbial growth as monitored by total plate count, yeast and mold, lactic acid bacteria, and Pseudomonas spp. by about 1 log cfu/g under AP. The combination of marinade and antimicrobials under AP and VP decreased growth of spoilage-causing microorganisms by 1.5 to 4.8 and 2.3 to 4.6 log cfu/g, respectively. Change in pH in VP meat was less than 0.5 in all treated samples including the control. Marination decreased the lightness of the meat (L*) and significantly (p < 0.05) increased the redness (A*) and yellowness (B*). Overall acceptability was highest for marinated samples with 0.5% BR.

Preservative effect of pomegranate-based marination with ß-resorcylic acid and cinnamaldehyde on the microbial quality of chicken liver.

Chicken liver is considered a delicacy in the Middle East where pomegranate molass is commonly used as a salad dressing and in marinade recipes. Marinated chicken liver is a common entrée and represents a value-added product compared to the otherwise unmarinated liver which commands a lower price. The aim of this study was to investigate the inhibitory effects of a pomegranate-based marinade alone or following the addition of cinnamaldehyde or ß-resorcylic acid on the spoilage microorganisms present in chicken liver during storage for 14 d at 4°C or under mild temperature abuse conditions (10°C). The pH and microbial populations of total plate count (TPC), lactic acid bacteria (LAB), Pseudomonas spp. (PS), yeast and mold (YM), and Enterobacteriaceae (EN) were tested during the storage period and the shelf life was determined (defined as 107 log cfu/g). Sensory analysis was also conducted. The pH increased by a greater extent in unmarinated samples as compared to marinated samples (with or without antimicrobials) upon storage. The initial TPC, LAB, PS, YM, and EN microbial populations in the chicken liver were 3.85 ± 0.79, 3.73 ± 0.85, 3.85 ± 0.79, 3.73 ± 0.87, and 3.69 ± 0.23 log cfu/g, respectively. The marinade decreased the microbial populations by 2 to 4 log cfu/g. The marinade and antimicrobial mixture decreased the microbial populations by 3 to 4 log cfu/g. Except for 1 sample, none of the marinated chicken liver samples with or without antimicrobials reached the end of shelf life even up to 14 d of storage at both 4°C and 10°C. The overall sensory score was rated around 6/9 for the treated samples.

Effect of Eugenol, Vanillin, and ß-Resorcylic Acid on Foodborne Pathogen Survival in Marinated Camel Meat.

The combined inhibitory effect of essential oils (EOs) with meat-based marinades has not been fully studied. Therefore, the present study aimed to gauge the effect of a yogurt-based marinade when individually combined with three EOs, namely eugenol (EU), vanillin (VA), or ß-resorcylic acid (BR) on camel meat cubes inoculated with Listeria monocytogenes, Salmonella spp., and Escherichia coli O157:H7 during storage. Fresh camel meat cubes of 10 g were inoculated with bacteria and dipped in the mixture of marinade and EO. Overall, the study had six EO treatments (EU 0.5%, EU 1%, VA 0.5%, VA 1%, BR 0.5%, and BR 1%) and two controls (meat without marinade and marinated meat). Treated meat cubes were stored at 4°C or 10°C for 1, 4, and 7 d. Adding only marinade to the camel meat at 10°C decreased the pathogens by 0.8-2.4 log CFU/g. At 10°C, BR decreased L. monocytogenes, E. coli O157:H7, and Salmonella spp. by 2.0, 1.5, and 1.3 log CFU/g, while EU caused a decrease (p < 0.05) of 1.9, 1.2, and 0.9 log CFU/g, respectively. Similarly, VA caused a reduction in these microorganisms of 1.3, 1.1, and 1.0 log CFU/g, respectively (p < 0.05). The combination of marinade and EO resulted in a decrease of the pathogens ranging from 0.9-1.4 and 2.8-3.7 log CFU/g at 4 and 10°C, respectively. The antimicrobial efficacy of EO alone or when combined with marinade was higher at 10°C than at 4°C with all three pathogens at both 0.5% and 1%. Overall, EOs were found to enhance the microbial safety of camel meat. In addition, they are antimicrobials that occur naturally, require a minimum investment, and may prove to be a great asset for marinated camel meat producers.

Inhibition of spoilage bacteria on marinated chicken by essential oils under aerobic and vacuum packaging.

"Chicken tawook" is a marinated boneless chicken entrée consumed in the Middle East. The aim of this study was to determine whether bioactive essential oil (EO) components carvacrol (CA), cinnamaldehyde (CI), and thymol (TH) would delay the growth of microorganisms causing tawook spoilage during aerobic (AP) or vacuum (VP) packed storage. The EOs at 1% and 2% were mixed individually with the marinade. The samples (10 g of chicken cubes with 1.2 g of marinade - with or without EOs) were stored in bags under AP and VP (Geryon® ) for 7 days at 4 ± 1°C and abusive conditions (10 ± 1°C). Two control samples consisting of meat chunks and tawook without EO were used. The microflora numbers were greater at 10°C than at 4°C, and the marinade worked additively with AP against anaerobes, yeast and mold (Y & M) and lactic acid bacteria. It also worked additively with VP against aerobic bacteria recovered as Pseudomonas and the total plate count. EO components were observed to decrease microbial populations by a maximum of 4 to 6 log colony-forming unit (CFU)/g depending on the type of microorganism. The combined mixture of marinade and 2% EO (CA, CI, and TH) resulted in the greatest reductions of all spoilage microorganisms at 10°C under AP on the last day of storage. Overall, VP was more effective (p < 0.05) than AP in controlling microorganisms at both 4 and 10°C. This study provides an affordable and natural alternative for extending product life. PRACTICAL APPLICATION: The use of EOs in marinated chicken (tawook) is expected to help producers reduce spoilage and extend shelf-life of the product when stored at refrigeration temperatures. EOs provide a cheaper alternative and are naturally sourced. Vacuum packaging will increase the shelf-life of marinated chicken tawook and facilitate its storage and transportation.

Pesticide residues in fresh fruits imported into the United Arab Emirates.

Pesticides are a major public health issue connected with excessive use because they negatively impact health and the environment. Pesticide toxicity has been connected to various human illnesses by means of pesticide exposure in direct or indirect ways. A total of 4513 samples of imported fresh fruits were collected from Dubai ports between 2018 to 2020. Their contamination by pesticides was evaluated using gas chromatography combined with mass spectrometry (GC-MS/MS) and liquid chromatography-mass spectrometry (LC-MS/MS). The display of monitoring results was based on the Maximum Residue Limit (MRL) standard as per the procedures of the European Union. Eighty-one different pesticide residues were detected in the tested fruit samples. In 73.2% of the samples, the pesticide levels were ≥ MRL, while 26.8% were > MRL standards. Chlorpyrifos, carbendazim, cypermethrin, and azoxystrobin were the most frequently detected pesticides in more than 150 samples. Longan (81.4%) and rambutan (66.7%) showed the highest number of imported samples with multiple pesticide residues > MRL. These results highlight the need to continuously monitor pesticide residues in fruits, particularly samples imported into the United Arab Emirates (UAE). Fruit samples with residues > MRL are considered unfit for consumption and prevented from entering commerce in the UAE.