Study On High Oxygen Preservation Technology Of Fresh-cut Watercored Apples

Fresh-cut fruits and vegetables are nutritious,convenient,and fast,so consumers favor them.However,the processing of fresh-cut fruits and vegetables caused a certain degree of mechanical damage,which aggravated the deterioration of the quality of fresh-cut fruits and vegetables.This paper studies the processing technology of fresh-cut watercored apples from high oxygen prestimulation,color-preserving agents,and high oxygen packaging.The aim was to find a high-efficiency and environment-friendly preservation technology for fresh-cut watercored apples.Quality during storage determines optimal processing and storage conditions.The main research results are as follows:（1）Short-term high oxygen（75%and 95%）prestimulation promoted the synthesis of phenolic compounds,inhibited the oxidative metabolism of phenolic compounds,and increased the activities of POD,CAT,and PAL in fresh-cut watercored apples while maintaining the integrity of cell membrane.Short-term high oxygen prestimulation（O₂≥75%）of whole fruit regulates the metabolic pathway of phenylalanine and synthesizes polyphenols to make apples in an ISR state.Thus,maintaining the cell membrane’s integrity and inducing fruit resistance to browning.（2）The single factor test showed that 1.0%phytic acid,1.0%kojic acid,0.8%EDTA-2Na,and 50℃color preservation temperature made the fresh-cut watercored apples have the best color.After response surface optimization,the optimal color protection method was phytic acid 1.1%,kojic acid 1.0%,EDTA-2Na 0.9%,and soaking temperature 52℃.The optimized color protection method was used to treat the fresh-cut watercored apples,and the browning index（BI）,hardness,and the total number of colonies of fresh-cut apples were significantly inhibited after being stored at 4℃for 8 days（P<0.05）.The contents of soluble solids（SSC）and titratable acid（TA）were not significantly affected.（3）Both 75%and 95%high oxygen packing can maintain high oxygen levels in the pack during storage.75%and 95%hyperoxia packing had no significant effect on fresh slices’SSC and TA contents,promoted PAL activity and the accumulation of total phenols（TPC）and inhibited the BI value polyphenol oxidase（PPO）and POD activities of fresh-cut watercored apples.However,the 95%high oxygen packaging group had higher relative conductivity,malondialdehyde（MDA）content,cell membrane damage rateand,lower hardness and sensory scores.