Effects of antioxidants and modified atmospheres on the storage stability of the pecan kernel

Abstract

The effects of antioxidants and modified atmospheres on the storage stability of the pecan kernel were studied. Samples which had been stored for one year at 35° to 40°F, were shelled. The sample halves were chopped into thirds, treated, and stored in sealed #303 cans at 85±2°F for 15 weeks. Antioxidant treatments were 0.02% and 0.05% by weight of α, γ, and mixed tocopherols, 0 .02% by weight of TBHQ, and BHA and BHT. A nitrogen flush and a vacuum were used to modify the headspace atmosphere. Quality was measured in terms of Hunter Lab color analyses, GC volatile analyses, and sensory evaluations. Treatments of a vacuum and a nitrogen flush were effective in preserving the quality of the pecan kernel as measured by Colors L and b, and a sensory panel color and flavor. The α, γ, and mixed tocopherols, at levels of 0.02% and 0.05%, had significant effects in preserving the color of the kernel testa as measured subjectively and by Color b. All, except the α-tocopherol at the 0.02% level, significantly reduced the flavor loss during storage. Also, the γ and mixed tocopherols significantly reduced the amount of headspace pentane produced. TBHQ and BHA and BHT were ineffective in preserving the quality of the pecan kernel during storage. On the basis of this study, the optimum storage treatment would be either the use of a vacuum or a nitrogen flush. The α, γ, and mixed tocopherols also would have a significant effect on preserving the color of the pecan kernel, but overall, these treatments are not as effective as the vacuum or nitrogen flush treatments.