Changes in color, PPO enzyme activity and total phenolics were assayed during 60 days of storage at 4±1°C. Fresh walnuts were stored in eatheraqueous environment (AE) or dry environment (DE) and color (L*), phenolics (by using Folin-Ciocalteu method) and PPO enzyme activity were investigated at 15-days intervals. Our results illustrated that during storage at low temperature, AE inhibited PPO enzyme activity and the reduction of L* was less profound in AE stored kernels, but the levels of total phenolics in DE stored nuts were more than AE stored walnuts. To conclude, this study showed the potential of using aqueous environment for storage of fresh walnuts during cold storage.
