Effects of different modified atmosphere packages on quality of fresh walnuts during cold storage

To select appropriate modified atmosphere( MA) package of fresh walnut during cold storage,‘Liaohe 2'fresh walnuts were packed in Thn- PE 11( 11 μm in thickness),PE30( 30 μm in thickness),PE 50( 50 μm in thickness),Thk- PE 90( 90 μm in thickness) packages and ordinary PE package( as control) at( 0 ± 1) ℃.The sensory quality,the weight loss rate,the fine fruit rate,CO₂ and O₂ volume fraction,as well as contents of fat,crude protein and soluble protein,and peroxide value( PV),carbonyl value( CV) were monitored. The results indicated that all MA packages could obviously improve the sensory quality and keep the water retention capacity of fresh walnuts in which PE 30 was the best package with a significant good quality during storage. Therefore,PE30 was identified as the optimal package for the preservation of fresh walnuts during cold storage.