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In this study, the effect of rosemary extract in two free and encapsulated forms to increase the shelf life of beef meat during a 28‐day refrigerated storage period was investigated. For this purpose, rosemary was extracted using different extraction methods including ultrasound, solvent, and supercritical fluid extraction. The amount of phenolic compounds, antioxidant properties (free radical scavenging capacity of DPPH radical, ferric reducing antioxidant power), and antimicrobial activity of rosemary extract against pathogenic bacteria were evaluated. According to the results, the highest amount of phenolic compounds, antioxidant, and antimicrobial activity was observed in rosemary extracted by ultrasound method that used for next study (p < .05). In order to encapsulation of the rosemary extract, basil seed gum and soybean protein isolate separately and in combination form (1:1 w:w ratio) were used as carriers. Based on the particle size, zeta potential, and encapsulation efficiency tests, the best carriers were soybean protein isolate that used as a carrier for encapsulation. Then, to investigate the effect of rosemary extract to increase the shelf life of beef meat, 5 treatments including control, rosemary extract with concentrations of 800 ppm and 1,600 ppm, and nano‐capsulation form of it with 800 ppm and 1,600 ppm concentrations were selected and they were periodically evaluated for chemical and microbial analysis (peroxide value, Thiobarbituric acid, color index, pH, and total viable count). The results showed that rosemary extract has an antimicrobial and antioxidant properties which could increasingly delay microbial spoilage and lipid oxidation of beef meat fillets, nano‐capsulation form of rosemary could increase these qualities. The best results were observed in nano‐capsulation of rosemary extract with 1,600 ppm (p < .05) as well as increased the shelf life of fillets till 21st day. Therefore, it seems that encapsulated rosemary extract could be used as a natural preservative in beef meat and meat products.

The effect of extraction methods (ultrasound and supercritical fluid) and solvents (ethanol, ethanol/water (50:50) and water) on the phenolic compounds and antioxidant activities of celery (Apium graveolens) extracts was evaluated to determine the most suitable extraction method for protective effects on stabilizing canola oil (CAO) during thermal condition (24 h at 180C). Ultrasound ethanol/water extract was found to have the highest phenols compounds (438.75 mg gallic acid equivalents/g sample) and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl [DPPH] and oxidative stability index 98.71 % and 7.1 h, respectively). Then, this extract was added to CAO. Peroxide value, carbonyl value, polar compound, acid value conjugated dienes value and color index were taken as parameters for evaluation of stabilization efficacy of the celery extract. Results from different parameters were in agreement with each other, suggesting higher efficiency of celery extracts followed by tertiary butylhydroquinone and control treated (without additives), respectively. PRACTICAL APPLICATIONSLipid peroxidation is responsible for the quality deterioration of vegetable oil, fats and other food systems. Thus, the use of antioxidants to minimize the oxidation of lipids in food materials is extensively practiced. Recently natural antioxidants have gained increased interest because natural food ingredients are safer than synthetic ones. The result of this study showed that celery extracts have antioxidant activity and it can replace synthetic antioxidant tertiary butylhydroquinone in canola oil.

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