Quality preservation of walnut kernels using edible coatings

GROSSO AL; ASENSIO CM; NEPOTE V; GROSSO NR

GRASAS Y ACEITES

INST GRASA SUS DERIVADOS

Lugar: Sevilla; Año: 2018 vol. 69

0017-3495

The objective of this work was to evaluate the performance of various edible coatings in preserving the quality of walnut kernels (W) during storage. Three edible coatings were prepared: carboxymethyl cellulose (CMC), methyl cellulose (MC) and whey proteins isolates (WP). Coated and uncoated walnuts (WC) were stored for 210 days at room temperature (23±2 °C). After 210 days, WC presented the highest peroxide value (PV = 3.06 meqO2/kg), conjugated dienes (CD = 3.01) and trienes (CT = 0.31), pentanal, nonanal, hexanal, and decane,5,6-bis(2,2-dimethylpropylidene) contents. Meanwhile, WMC showed the lowest PV (1.20 meqO2/kg) , CD (2.26) and CT (0.17) and the lowest decrease in carotenoid content (0.60 mg/kg). The L* value measured in walnut oil decreased in all samples. MC, CMC and WP coatings showed protection on walnuts against deterioration process. MC coating displayed the best performance.