The present study was undertaken to evaluate antimicrobial and antioxidant effect of essential oils on the quality of fresh (raw, ready to cook) chicken sausages. Several preliminary trials were carried out to optimize the level of four essential oils viz

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Purpose – The purpose of this paper was to develop an antimicrobial edible film coated with essential oils for packaging application with characterization of its physicochemical properties. Livestock products especially meat products need special packaging system for protection. The most well-known packaging materials are polyethylene or co-polymer-based materials which have led to serious ecological problems due to their non-biodegradability and non-renewable nature. There has been a growing interest for edible films in recent years trying to reduce the amount of wastes, capable of protecting the food once the primary packaging is open, and because of public concerns about environmental protection. Various kinds of antimicrobial substances can also be incorporated into edible films to improve their functionality, as these substances could limit or prevent microbial growth on food surface. Design/methodology/approach – Biopolymers such as carrageenan and carboxymethylcellulose and their various combinations were tried to develop an edible film. The levels of antimicrobial substances such as oregano and thyme essential oils were standardized on the basis of their minimal inhibitory concentration against Escherichia coli, Salmonella pullorum, Staphylococcus aureus and Listeria monocytogenes. Standardized edible film coated with standardized concentration of essential oil was examined for different physicochemical properties and compared with edible film without essential oil. Findings – In total, 1.5 per cent (w/v) solution of carrageenan was found best suited biopolymer for edible film formation on the basis of thickness, transparency and elongation ability. Combined concentration of oregano (0.02 per cent) and thyme (0.03 per cent) essential oils were found to be best suited for coating the edible film as antimicrobial application. Research limitations/implications – Future research may benefit from the present attempt in evaluating the potency of easily available agricultural by produces for preparation of economically viable edible film incorporated with various natural biopreservatives in combination for the enhancement of shelf life. Originality/value – Antimicrobial packaging for enhancing the quality and shelf life of stored meat products offers great scope for further research in this field. Moreover, the literature pertaining to the application of edible films containing biopreservative for chicken meat products is very limited.

Natural plant pigment, anthocyanins have the capability to change its color with the change of its structure influenced by changing pH. This feature of anthocyanin has been harnessed to design a meat products quality indicator. In the present experiment anthocyanin rich Jamun fruit (Syzgium cumini) skin extract was used to develop quality indicator by immobilizing on filter paper strips with the purpose of application in chicken patties packets stored at refrigeration temperature (4 ± 1 °C). The indicator changed its color from violet to yellow due to changed pH in it when it was attached inside packet of chicken patties during storage, due to reaction with volatile basic compounds generated from meat. During storage for 21 days, various changes in quality attributes of chicken patties viz., pH, Total volatile basic nitrogen (TVBN), ammonia level, color value, sensory attributes and microbial evaluation were estimated. The pH decreased (P \ 0.5) from 6.22 to 6.04. TVBN and ammonia and level increased significantly (P \ 0.5) throughout storage. Redness, yellowness, hue and chroma value gradually changed during storage. Sensory scores also decreased significantly (P \ 0.5). Microbial count also increased (P \ 0.5) during this time. The experiment showed that, during storage, the color changing pattern of quality indicator was well correlated with the changes in quality attributes of chicken meat patties. Therefore, it is expected that the developed quality indicator can provide a convenient, non destructive, visual mean to monitor the meat products quality during refrigerated storage.

A blend of oregano and thyme essential oils (EOs) incorporated edible film was evaluated to improve the storage quality of chicken meat patties. Several preliminary trials were carried out to optimize the levels of bio-polymer to obtained desired edible film as a carrier and blend of EOs as bio preservatives. Preliminary studies indicated that 1.5% (w/v) solution of carrageenan as bio-polymer and 0.10% (v/v) oregano with 0.15% (v/v) thyme EOs in blend form as antimicrobial were suitable. Chicken meat patties wrapped with edible film incorporated with aforementioned EOs, packaged aerobically were stored at refrigeration temperature (4 ± 1 °C) for further studies. Results of refrigeration storage, showed that control samples had significantly higher pH and thiobarbituric acid reacting substances value than EOs treated products. There were significantly lower microbial counts observed in treatment samples (with EOs) and found well within permissible limit as compared to control. All the treatment samples showed lower or comparable flavour score in regard with control. It was found that shelf-life of chicken meat patties increased significantly (< 0.05) during refrigerated storage and showed acceptable quality up to storage period of 30 days.