Effects of Sonication and Edible Coating Containing Rosemary and Tea Extracts on Reduction of Peanut Lipid Oxidative Rancidity

Abstract

Rancidity due to the lipid oxidation process is a critical factor influencing the quality of roasted peanuts. Sonication in combination with edible coatings added with plant extracts may extend the oxidative stability of peanuts. Peanuts were roasted at 178°C for 15 min, subjected to sonication in hexane for 10 min, and then coated with carboxymethyl cellulose (CMC) solution mixed with rosemary, tea extracts, and α-tocopherol and stored at 35°C for 12 weeks. The oxidative stability of the samples was investigated by measuring the oxidative stability index. Reduction in oxidation of 66.1% and 10.4% was observed for samples roasted and coated with extracts of rosemary and tea, respectively, as compared to uncoated sample. However, the oxidative stability of samples roasted-sonicated and coated with extracts of rosemary and tea was improved by 100.7% and 28.1%, respectively, in relation to the control. Sonication beyond coating improved the oxidative stability of the samples mixed with rosemary, tea extracts, and α-tocopherol by 10.3%, 12.1%, 34.6%, and 17.7%, respectively. The L * , a * , and b * values indicated that the peanut coated with CMC mixed with rosemary, tea extracts, and tocopherol at different concentration levels did not have significant (P < 0.05) color change during the 12-week storage at 35°C.

Gum Cordia: A novel edible coating to increase the shelf life of Chilgoza (Pinus gerardiana)

“…The effectiveness of coating with tocopherol is highly dependent on the concentration and temperature (Tasan & Demirci, 2005). Similar, pro-oxidant effect of alpha tocopherol has been reported in peanut as well (Wambura et al, 2010;Wambura, Yang, & Mwakatage, 2011).…”

“…The role of phenolic compounds has been reported to improve the oxidation retardation capabilities of edible coatings (Mestrallet, Nepote, Quiroga, & Grosso, 2009;Wambura et al, 2010Wambura et al, , 2011. It is therefore, most likely that the effectiveness of methanolic extract of Cordia is due to these compounds.…”

Development of Edible Films and Coatings with Antimicrobial Activity

“…The WVP of films was determined to be 0.232×10 −10 -1.160×10 −10 g/ms Pa, σ r took values between 17 and 44 N/mm 2 and ε r between 14% and 97%, Moreira et al (2009) analyzed the effect of a CMC coating during drying process on the quality of butternut squash slices and observed a slight improvement in weight loss and ascorbic acid retention in comparison with control samples without any coating. In addition, Wambura et al (2008) analyzed the effects of a CMC-based edible coating containing rosemary and tea extracts on the reduction of lipid oxidative rancidity. Reduction in oxidation of 66.1% and 10.4% was observed for samples roasted and coated with CMC films formulated with extracts of rosemary and tea, respectively, as compared to uncoated sample.…”

Antioxidant Containing Gum Cordia Coatings for Control of Peanut Oxidation

“…Edible coatings prevent moisture loss and reduce oxygen diffusion in nuts (Quezada-Gallo 2009). Carboxymethyl cellulose (CMC; Wambura et al 2008Wambura et al , 2010Wambura et al , 2011, whey protein isolate (WPI; Mate et al 1996;Min and Krochta 2007;Han et al 2008) and corn zein (Wambura et al 2008) have been reported as coatings to retard the oxidative rancidity in peanuts. Carboxymethyl cellulose (CMC; Wambura et al 2008Wambura et al , 2010Wambura et al , 2011, whey protein isolate (WPI; Mate et al 1996;Min and Krochta 2007;Han et al 2008) and corn zein (Wambura et al 2008) have been reported as coatings to retard the oxidative rancidity in peanuts.…”