Effect of detoxified Rhus verniciflua extract on oxidative stability and quality improvement of raw chicken breast during cold storage.

This study investigated the utilization of detoxified Rhus verniciflua (RV) extract as a natural antioxidant to extend the shelf life of chicken breast meat during storage. Pre-heating at (35°C, 100°C, 120°C, and 140°C) was conducted on heartwood of RV prior to extraction to improve its antioxidant activity and remove the allergenic compound urushiol. The antioxidant activity was the highest when RV pre-heated at 120°C with the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) scavenging activity observed at 62.29 EC50 µg/mL and 12.11 IC50 mg/mL, respectively. Pre-heating also significantly increased the total phenolic content (TPC), with the highest improvement was seen at 120°C, 100°C, and 140°C respectively, wherein 35°C shared no difference with the raw RV (RRV). Urushiol content was vanished following pre-heating at 120°C and 140°C. With respect to these result, pre-heating treatment at 120°C was applied before the extraction of the heartwood of RV. Prepared breast meat sample was dipped into distilled water as a negative control, 0.02% butylated hydroxytoluene (BHT) as positive control, and a solution containing detoxified RV extract (0.10%, 0.25%, 0.50%, 1.00%) at 4°C for 60 min. Treatment group with 0.50% and 1.00% addition increased the redness and yellowness value on day 6 and day 3 of storage respectively (p < 0.05). The pH value of breast meat was also increased in treatment of 0.50% and 1.00% on day 0, but subsequently lower until end of storge day compared to control negative (p < 0.05). Furthermore, 0.50% treatment exhibited a higher antioxidant activity, stronger inhibition of the microbial growth evaluated by total viable count and maintaining a lower total volatile basic nitrogen among treatments (p < 0.05), unless for BHT and 1.00% treatment groups (p > 0.05). It indicates a similar efficacy of detoxified RV extract with that of positive control treated with BHT. The results of this study suggested that dipping chicken breast meat into a solution containing 0.50% of previously pre-heated RV heartwood at 120°C could be a promising natural antioxidant for extending the shelf life, and at the same time improve its quality during storage.