Effect of chitosan‐propolis edible coatings on stability of refrigerated cachama (Piaractus brachypomus) vacuum‐packed fish fillets

• Published in: Packaging technology & science 2019-03, Vol.32 (3), p.143-153
• Main Authors: Piedrahíta Márquez, David Guillermo, Fuenmayor, Carlos Alberto, Suarez Mahecha, Héctor
• Format: Article
• Language: English
• Subjects: Aquaculture; cachama; Chitosan; Coating effects; edible coating; Fillets; Fish; Food packaging; Free radicals; Immersion coating; Indicators; Lipids; Meat; Muscles; Nitrogen; Oxidation; packaging aid; Parameters; Propolis; Quality; Shelf life; Stability; Texture
• ISSN: 0894-3214; 1099-1522
• DOI: 10.1002/pts.2422

The effect of chitosan‐based coatings containing ethanolic extracts of propolis (EEPs) on the quality of chill‐stored, vacuum‐packed fillets of cachama, an emerging aquaculture species of fish native to the Amazon basins, was evaluated. Coatings were prepared by adding propolis to chitosan following two different strategies: (1) incorporation of microencapsulated EEP and (2) direct incorporation of EEP. Fillets were dip‐coated, vacuum‐packed in medium‐oxygen barrier bags, stored at 4°C, and their quality was evaluated during 20 days, by monitoring lipid oxidation indexes, physicochemical parameters, microbiological quality indicators, texture profile, and sensory acceptance. Chitosan‐EEP coatings significantly increased the time stability of physicochemical, microbiological, and sensory quality indicators of the fish meat compared with control treatments (uncoated vacuum‐packed fillets). In particular, the secondary lipid oxidation of the coated muscles was 12% to 15% lower compared with uncoated samples after 12 days; pH and total volatile base nitrogen (TVB‐N) presented a slower increase in the coated samples; and a greater inhibition of coliforms was observed between days 8 and 16. The chitosan‐EEP coatings had a positive effect in both texture stability and sensory acceptance of the products during storage. Moreover, chitosan coatings with encapsulated EEP had better impact on the evaluated sensory quality parameters. The results indicate that the combination of the barrier properties of chitosan with the bioactive properties of propolis compounds against oxidative free radicals and microbiological deterioration allowed for the edible coatings to extend the shelf life of this aquaculture product with respect to conventionally vacuum‐packed fillets. The effect of chitosan‐propolis edible coatings on quality indexes of fresh cachama fillets was investigated. Fillets were dip‐coated, refrigerated, and vacuum‐packed during 20 days in medium oxygen‐barrier bags. Uncoated fillets were used as a negative control. Ethanolic extracts of propolis (EEP) were added to chitosan either by direct incorporation or after their encapsulation in maltodextrin microcapsules. Coating treatments positively affected fat and protein stability, textural profile, and microbiological quality, demonstrating their effectiveness as packaging aids; using previously encapsulated propolis was proven more advantageous in terms of sensory acceptance.