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

Cordia myxa is a deciduous tree, which grows nearly all over the Indo-Pak subcontinent. The ripe fruits contain an anionic polysaccharide having good adhering property. Chilgoza (Pinus gerardiana), specie of genus Pinus (pine nuts) grows in Pakistan, Afghanistan and India. It is a rich source of unsaturated fatty acids but the un-shelled nuts are highly susceptible to rancidity. An effort was made to investigate the efficacy of gum Cordia in comparison with carboxy methyl cellulose (CMC) as edible coating to retard this oxidation. Gum Cordia and CMC with and without natural antioxidants were used in this study. Methanolic extract of C myxa and alpha tocopherol were selected as antioxidants. Chemical and sensory analyses were performed on coated and uncoated pine nuts stored at 35 degrees C for 112 days. Significant differences (p < 0.05) between coated and uncoated samples were observed. Samples coated with gum Cordia containing the extract of C. myxa exhibited highest (ca. 95%) increase in shelf life followed by CMC and the C. myxa extract (ca. 60%), gum Cordia (ca. 25%), and CMC (ca. 15%); based on peroxide value (20 meq.O-2 kg(-1)). However, samples treated with alpha tocopherol did not improve the oxidative stability. (C) 2012 Elsevier Ltd. All rights reserved.