Preliminary Studies On Postharvest Commercial Handing Technology Of Figs

As one of the oldest known fruits,fig has a very high nutritional and medicinal value.Fresh fig presents a challenge for postharvest technology.Because of highly perishable and susceptible to postharvest diseases,fig has a short postharvest life,1 or 2 days at ambient temperature.So fig is difficult to store,transport,and sell in long period.There are many studies on keeping fig’s quality,however none of them systematically researched the commercial storage and fresh keeping technique of fig.In this work,characteristics of’Branswick’ figs during maturing were studied.Effects of pre-cooling,wax treatment on the postharvest storability of fig during ambient temperature or cold storage were also studied.Results were as follows:1.Branswick figs in the growth phase Ⅲ were divided into four groups according to the maturity,which are seven,eight,nine and ten grade of maturity.Indexes of physiology,quality and apparent characteristics of samples were measured.Results showed that dramatic changes in qualities of fig fruit in the phase Ⅲ occurred in the period of seven to eight grade of maturity.Respiration rate,firmness and content of vitamin C（Vc）of fig fruit decreased,but weight of single fruit,size of ostiole in figs,content of total soluble solids（TSS）and reducing sugar increased along with the ripening of figs.During the period of figs’ maturation,content of titratable acid（TA）remained at a relatively low level and peel color changed from turquoise to yellowgreen then to amber.Rapid advance in superoxide anion（O2）formation rate occurred in the period of nine to ten grade of maturity.The degree of membrane lipid peroxidation increased along with the fruit ripening.Activity of superoxide dismutase（SOD）increased before nine grade of maturity,and then decreased.Activity of catalase（CAT）had a same variation tendency as SOD.While activity of peroxidase（POD）and ascorbate peroxidase（APX）moved in the opposite tendency of SOD and CAT during fruit ripening and mature.2.’Branswick’ figs were treated with four types of wax in different concentrations.Figs were stored under the conditions of air temperature at 25℃,and relative humidity（RH）at 55%.Results showed that,figs treated by wax BVOD had a lower weight loss and higher L*value,but the quality of fruit deteriorated.The adverse effect of wax BVOD on fruit quality was significant.When the wax concentration was 60%,SP-1,CFW,BVOF could maintain the peel brightness,inhibited the increase of rooting rate and weight loss.Figs treated with wax SP-1 had the lowest rotting rate and weight loss,highest brightness.So,SP-1 was better than other waxs.3.’Branswick’ figs were treated with 60%diluted wax SP-1.After treatment,figs were stored at 25℃,55%RH and（2±1）℃,RH 90-95%.Results showed that rotting rate and weight loss and color difference were decreased significantly by waxing.Vc,reducing sugar and soluble protein content were higher than that of control significantly.Respiration rate,O₂^-· formation rate and malondialdehyde（MDA）content were inhibited by wax significantly.Wax treatment can delaye the decreaseing of SOD,POD,CAT,APX and polyphenoloxidase（PPO）activity.Figs treated by waxing combined with precooling had a better effect on maintaining fruit quality,decreaseing the rotting rate,weight loss than waxing only.At ambient tempreture,waxing combined with precooling was more positive than low tempreture.Combined with precooling can enhance the preservation effect of waxing on fig fruit.Therefore,in the commericial process of storage and preservation,figs with no pests,no mechanical damage,in eight grade of maturity would be choosed to be precooled,waxed and stored.These combined treatments could reduce roting rate,weight loss,shrinkage and pericarp browning of fig,maintain quality of postharvest fruit during storage,and prolong fig fruit storage period.