The Effects Of H₂S And CaCl₂ Treatment On The Storage Properties Of Peach Fruit

The rapid ripening and softening process of peach fruit and poor storage and transportation performance seriously affect its market supply period.In this paper,Na HS aqueous solution were used as the H₂S donor to explore the effects of treatment with H₂S and CaCl₂on the storage performance of‘Yanhong’peach fruit.The main results were as follows:1.The fruit quality and storage of 1mmol·L^-1or 2mmol·L^-1Na HS treatment were better than that of the control,and 2mmol·L^-1Na HS treatment was better.The combination of H₂S and CaCl₂and the treatment alone（H₂S,H₂S+CaCl₂,CaCl₂,denoted by T1,T2,T3,respectively）could delay the decline of fruit hardness;On the 28th day,the hardness of T1,T2and T3 treatments were 1.48,2.12 and 1.61 times of the control,respectively.During the whole storage period,the SSC of the fruits under different treatments was always higher than that of the control,while the browning index of the fruits was lower,and the combination treatment had the best effect.2.During cold storage and shelf life,compared with the control,the activities of SOD,POD,CAT,APX,GR and other antioxidant enzymes in the fruits of different treatments increased,and the contents of GSH,ASA and other antioxidant substances remained at a high level,reducing the accumulation of ROS（H₂O₂and O₂·^-）in the fruits.LOX activity,MDA content and cell membrane permeability of fruits under different treatments were always lower than those of the control during the whole storage process,and the combination treatment had the best effect.At 7d,there was no significant difference between T2and T1 and T3 treatments.At 28d,the APX activity of T2 treatment was 2.12,1.12 and 1.35times that of the control,respectively.The cell membrane permeability and MDA content of T2 treatment were 20.94%and 36.72%lower than control,respectively.3.The activities of CX and PG in the fruits of different treatments were significantly lower than those in the control during cold storage and shelf life,and the contents of protopectin and cellulose in the fruits were correspondingly higher than those of the control.At 28d,the protopectin contents of T1,T2 and T3 were 72.75%,101.38%and 78.93%higher than those of the control,respectively,and the combined treatment was superior to the single treatment.4.During the cold storage and shelf life,the activities of P5CS and PAL in the fruits of different treatments were significantly higher than those in the control,and the contents of proline,soluble sugar and total phenols in the fruits were higher than those in the control.But PPO activity was always lower than control.At 28d,the proline contents in T1,T2 and T3treatments were 1.71,2.03 and 1.29times higher than those in CK treatment,respectively.At28+3d,the proline content of T1,T2 and T3 were 1.55,1.62 and 1.26times of CK,respectively.The above results showed that H₂S and CaCl₂alone or combined treatment could enhance the antioxidant capacity of peach fruit,maintain a high level of total phenolics content in fruit,and delay the occurrence of fruit browning.Among them,the combined treatment had better effect.