In vitro Antioxidant Properties of E uryale ferox Seed Shell Extracts and their Preservation Effects on Pork Sausages

Abstract

Seed kernels of Euryale ferox are considered a healthy food product in China, and the shells containing high levels of polyphenols are currently unused. To examine the utilization of these by-products, three extracts were obtained from E. ferox seed shells (EFSS) using different solvent systems (EEA, EE-100 and EE-50 extracts). The major composition of the phenolic compounds in these extracts, their in vitro antioxidant properties and their preservative effects on pork sausages were investigated. The major phenolic compounds were gallic acid, epicatechin and rutin. Each extract exhibited strong antioxidant properties, high radical scavenging capacity and inhibition of lipid peroxidation. EE-50 was found to inhibit pH increases and prevent sausage products from lipid oxidation during storage. Furthermore, EE-50 was more effective when used in combination with monascus and NaNO2. The results suggest that EFSS extracts are a potential source of natural antioxidants and could be used for preservation of meat products. PRACTICAL APPLICATIONSEuryale ferox seed shell is the main by-product of E. ferox seed processing. The production of E. ferox seed shells is in the range of dozens of tons in China every year and this component is currently unused. Previously, I found that the seed shells contain high levels of polyphenols. Here, I show that extracts of E. ferox seed shells have significant antioxidant properties and contain high levels of rutin and catechin compounds. Thus, E. ferox seed shells can be a source of natural and functional antioxidants and serve as an alternative to synthetic antioxidants in food processing.

Natural Antioxidants from Seeds and Their Application in Meat Products

“…This outcome seems to explain the results obtained with a commercial cacao bean husk extract in the color of cooked pork sausage [93]. Conversely, Euryale ferox seed kernels extract (obtained using hydroethanolic solution followed by solvent evaporation at low pressure) did not affect the redness of cooked pork sausage [54].…”

“…Finally, Euryale ferox is a plant used in traditional medicine to treat leukorrhea, hernia, and pyodermas in the Chinese traditional medicine [60]. The seeds of this plant contain phenolic compounds such as gallic acid, catechin, and rutin [54].…”

“…According to the authors, the yellow mustard seeds had the highest antioxidant potential in comparison to brown and black mustard seeds during the refrigerated storage (15 days at 4 • C). The kernels obtained from Euryale ferox seed (500 mg/kg) were tested to prevent the oxidation of lipids in cooked pork sausage during 10 weeks [54]. The experiment carried out by Özünlü et al [59] indicated that ground acorn (1000 mg phenolics/L) was effective against the progression of lipid oxidation in raw chicken meat.…”

Effect of the addition of microcapsules with avocado peel extract and nisin on the quality of ground beef

“…Similar results were observed in meat patties, in which avocado peel extract reduced around 60% of the protein oxidation and 20% of the lipid oxidation of the system (Rodríguez‐Carpena, Morcuende, & Estévez, ). However, there are other studies in which agro‐industrial residues that contain polyphenols decrease the oxidation in meat and meat products (Monteiro et al, ; Zhang, ). Surprisingly, when encapsulated by other techniques (e.g., spray drying), the activity of these extracts decreases or changes.…”

Physicochemical properties and structure of starches of foxnut ( Euryale ferox Salisb.) from India and its application

“…Euryale ferox Salisb (Figure 1), a Nymphaeaceae member, is an aquatic crop cultivated primarily for its edible seeds in India, China, and other Southeast Asian nations (Zhang, 2015; Zhao et al., 2016). Common names include fox nut, gorgon nut, prickly water lily, black diamond etc.…”