Chemical and sensory property preservation of raw peanuts packaged in high barrier plastic bags under vacuum

MARTÍN M.P.; B X CAMILETTI; P R QUIROGA; GROSSO N R

Chicago

Congreso; IFT Annual Meeting and food expo 2015; 2015

Institute of Food Technologists

Peanut kernels have high oil content that is susceptible to rancidity. Oxidative deterioration can be inhibited or decreased by using packaging material with low oxygen permeability. The purpose of this study was to determine the chemical and sensory stability of raw peanuts packaged in high barrier bags under vacuum during storage. Raw peanuts type Runner were placed in two different packaging materials: high barrier plastic bags (ethylene vinyl-alcohol, EVOH) under vacuum and polypropylene ventilated bags (PP) used as control sample. The bags were stored in a dark room at 40°C and 60% relative humidity for 60 days. Peroxide value (PV), conjugated dienes (CD) and trienes (CT), and free fatty acids (FFA) were evaluated in the samples every 20 days. Sensory descriptive analysis was performed on the samples after roasting them. ANOVA and LSD Fisher test were used for statistical analysis. Significant differences ( = 0.05) were found between EVOH and PP control for all chemical indicators which increased with storage time. In EVOH samples, PV was from 0.38 to 0.62 meqO2 Kg-1 during storage. CD and CT increased from 1.11 and 0.10 (day 0) to 1.13 and 0.14 (day 60), respectively. These results were lower than those observed in PP. On the contrary, EVOH showed higher increase in FFA (0.05% at day 0 to 0.60% at day 60) than PP. The intensity of some sensory attributes changed during storage like cardboard and roasted peanutty flavors. Cardboard intensity ratings increased with storage time. EVOH samples showed lower increase with respect to PP samples. On the other hand, roasted peanutty decreased with storage time. This decrease was lower in EVOH than in PP. To stored raw peanuts packed in high barrier bag under vacuum helps to preserve their sensory profile and slows the increase of chemical lipid oxidation indicator (except FFA).