White striping prevalence and its effect on meat quality of broiler breast fillets under commercial conditions.

White striping (WS), characterized by white striations on the Pectoralis major muscle, is an emerging problem for the broiler industry. Thus, the impact of WS on meat quality has become a current research topic. In this context, a 2-year follow-up study, to reveal the prevalence of WS in broiler integrations, was undertaken. Additionally, a laboratory experiment was conducted to determine the oxidative quality during storage and the differences in proximate composition, colour and fatty acid and amino acid profiles of broiler breast fillets scored visually as normal, moderate and severe. In integrations, the WS incidence increased with increasing broiler age and more than 50% of breast fillets obtained from 32- to 35-day-old broilers and 36- to 39-day-old broilers had stripes with different scores. Lower protein and higher fat contents were measured in the moderate and severe scored fillets than the normal fillets (p < 0.001). Severe score stripes induced the formation of less redness on the ventral surface (p < 0.05) and a darker colour on the dorsal surface (p < 0.01). The lowest histidine, arginine and tryptophan amounts were determined in severe fillets (p < 0.05). Moderate and severe scored fillets were rich in polyunsaturated fatty acids implying that they were sensitive to lipid oxidation. That suggestion was further proven by the higher TBARS values. Freeze-thawing induced the formation of carbonyl compounds, but it did not cause differences in sulphydryl groups. Briefly, we suggest that different WS scores may affect the physicochemical and oxidative quality of breast fillets; however, more studies are needed to assert an accurate and explicit judgement.

Effect of chitosan-essential oil, a surface mold inhibitor, on microbiological and physicochemical characteristics of semidried fermented sausages.

Mold growth on sausage casing during processing is an important problem in fermented sausages. In this work, sausages were dipped into 1% chitosan (C), 1% thyme essential oil in 1% chitosan (CT), 1% rosemary essential oil in 1% chitosan (CR), 20% potassium sorbate (PS) as chemical antifungal, and 1% acetic acid solution (AA) as chitosan solver, or distilled water (DW) as control after fermentation (at day 4). The changes in microbiological (total viable count, lactic acid bacteria [LAB], Micrococcaceae, Enterobacteriaceae, and mold and yeast counts) and physicochemical attributes of the sausages during 12 days of processing were monitored. As expected, LAB were the most dominant microbiota in fermented sausages and the dipping process did not have any negative effect. Additionally, the treatment with C, CT, and CR suppressed the growth of spoilage microorganisms, which resulted in a significant reduction (P < 0.01) of about 1.4 to 1.6 log CFU/g in Enterobacteriaceae counts at day 12. The C, CT, and CR similarly suppressed the growth of fungi in the interior of the sausages, and the antifungal treatment significantly reduced (P < 0.01) the load of fungi on the casing. Throughout the study, approximately log counts of 3 and 4 in lower molds and yeasts in the casings treated with PS and CR were found, respectively, as compared to DW. Finally, the microbial quality of the end product was notably improved. PRACTICAL APPLICATION: Processing conditions such as high humidity and O2 in the ripening chamber result in undesirable fungal growth on the casings of the sausages. Fermented sausages are usually treated with weak acids such as sorbic or benzoic acids or their salts to inhibit mold growth during the drying process. However, increasing consumer demand to reduce the use of chemicals encourages the applications of natural antifungals.

Formation of heterocyclic aromatic amines in doner kebab cooked with different methods at varying degrees of doneness.

This study was designed to determine the formation of heterocyclic aromatic amines (HCAs) in two different types of doner kebab (yaprak doner-YD or mix doner-MD) cooked with different cooking methods (gas or electric) at varying degrees of doneness (rare, medium, well-done). In doner samples, nine common HCAs (IQ, IQx, MeIQ, MeIQx, PhIP, 4,8-DiMeIQx, 7,8-DiMeIQx, AαC, MeAαC) were detected. Additionally, the changes in the HCA precursors were evaluated. The initial concentration of precursors gradually decreased with the increase in doneness degree due to degradation or possible contribution in the Maillard reaction to form HCA compounds as a result of heat treatment (p < 0.05). Creatine content decreased, while creatinine content increased because of the conversion reaction. The two most abundant HCA in doner samples were 4,8-DiMeIQx and IQ, which measured in the range of 0.020-2.865 ng g-1 and 0.052-0.513 ng g-1, respectively. Other detected HCAs were determined in especially well-done samples. In conclusion, the diversity and the amount of each HCA compound in doner kebab samples showed variation depending on the effect of doneness degree, doner kebab type or cooking methods (p < 0.05).