Antioxidant and antimicrobial activity of red onion (Allium cepa, L.) extract nanoencapsulated in native seed gums coating and its effect on shelf-life extension of beef fillet

In this study, Alyssum homolocarpum (AH) and Lepidium sativum seed gum (LS) at different ratios 1:0, 1:1, and 0:1 utilized to encapsulate red onion extract (ROE). In the first step, the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity of ROE were characterized. Further, the DPPH and FRAP assay showed that ROE at 1600 ppm exhibited highly antioxidant potential (DPPH = 88.36%, FRAP = 35.42%), and used for encapsulation. The chemical, microbial and sensory properties of beef fillets were monitored at days 0, 4, 8, 12, 16, and 20 of storage at 4 °C. Our results indicated that encapsulated ROE in AH: LS coating was more efficient in retardation of microbial chemical reactions of coated meat fillet and the shelf life was extended from 4 to 16 days due to inhibition of bacterial growth, reduction in pH, peroxide value, thiobarbituric value and microbial growth. Also, free ROE showed good preservative than 200 ppm of synthetic BHT preservative. This study confirmed that the encapsulated ROE in AH: LS coating, is a potential coating to improve the quality and shelf life of beef fillet.