Frying stability of sunflower oil blended with jujube (Ziziphus mauritiana Lam.) leaf extract

Abstract

The aim of present study was to compare the effects of ultrasound‐assisted and microwave‐assisted extraction with solvent extraction method on antioxidant activities of jujube (Ziziphus mauritiana Lam.) leaf extracts in stability of sunflower oil during deep frying. The antioxidant activities of the extracts were evaluated by using 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH˙) radical scavenging and β‐carotene bleaching assays. Ultrasound‐assisted extraction was the most effective method on antioxidant activities of extracts and extraction yield of phenolic compounds compared to other extraction techniques. Protective effect of methanol–water extract of jujube leaf obtained with ultrasound‐assisted extraction (ULMW) at 500 and 700 ppm in stability of sunflower oil was compared to synthetic antioxidants by measuring total polar compounds (TPC), carbonyl value (CV), peroxide value (PV), free fatty acids (FFA), oxidative stability index (OSI), conjugated dienes (CD), and trienes values (CT). Results showed ULMW at 700 ppm had higher stabilization efficiency than synthetic antioxidants.

Heating, microwave and UV irradiation effects on oxidative stability of Sardasht red grape (Vitis vinifera cultiv. Sardasht) seed oil

“…The results of the current study were in good agreement with Delfanian et al . () who reported that sunflower oil treated with BHT resulted in significantly ( P < 0.05) lower CDV than control sample (without BHT). In another research, higher polyphenol amount was noted for microwave‐irradiated virgin olive oils than conventionally heated virgin olive oils (Brenes et al ., ).…”

Ziziphi spinosae Semen Oil Enhance the Oxidative Stability of Soybean Oil under Frying Conditions

“…Results obtained with Ziziphi spinosae semen oil agree with similar studies on other Ziziphus species. Mojtaba et al., [ 31 ] showed that sunflower oil containing 500 and 700 ppm extract of jujube leaf had a pronounced effect on resisting the formation of polar compounds. The results of another investigation indicated that soybean oil with 600 ppm extract of jujube fruit has a higher t 24 value than 100 ppm TBHQ.…”

Impact of Purslane (<i>Portulaca oleracea</i> L.) Leaves Extract to Enhance the Anti-oxidant Potential of Edible Oils during Heating

“…marker for major oil degradation and it is adequate at maximum of 25-27 for used frying oil 21 . The fresh soybean oil had a TPM content of 5.6 , reflecting the good quality of the oil used, as TPM content of unused oils normally ranges between 0.4 -6.4 27 . The TPM was found to increase during frying and had high correlation coefficient with heating time 28 .…”