Effects Of Different Nano Packing Materials On The Perservation Of Loquat Fruit

Loquat is mostly planted in the southern subtropical region of China,mature in the hot and rainy summer season.Loquat fruit,with delicate and juicy texture taste sweet and soft waxy,rich in nutrients,therefore it's deeply loved by consumers.However,due to the effect of warm and humid climate during the loquat harvested,when store at room temperature the decay will soon occur;affected by mechanical damage,pests and diseases,it is difficult to store and transport.At present,cold storage and chemical preservation are common preservation methods of loquat fruit.Low temperature can delay the decay of loquat fruit,but it will lead to the deterioration of the fruit lignification;As a result of excessive use of chemical preservation triggered food safety,environmental pollution and a series of problems.Due to its unique antibacterial activity,rot resistance,degradation of ethylene and regulation of gas,nano packaging materials have become the research hotspots in the field of preservation of fruits and vegetables.In this paper,the "Qingzhong " and "Da Wuxing" loquat fruit were used as materials to study the effect of nano-Ag,nano-TiO2 and nano-SiO2 packing materials on the quality,antioxidant capacity and nutrient content of the preservation of red-and white-flesh at room temperature;and further compared the the differences of red-and white-flesh loquat postharvest nutritional quality and antioxidant capacity.The results are as followed:1.Nano-Ag,nano-TiO2 and nano-SiO2 packing materials treatment can maintain better commodity of "Qingzhong5" and "Da Wuxing" loquat fruit,Which inhibit the increase in decay index,weight loss rate and hardness,as well as decrease the rate of decline in juice and titratable,acid soluble solids and Vc loss.Among them,nano-Ag packing materials had better inhibition of fruit decay index,while nano-SiO2 packing materials could retard the increase of weight loss rate and Vc content of loquat fruit better;the contents of TSS,TA and Vc in "Qingzhong" loquat fruit were higher than those in "Da Wuxing" loquat fruit during storage.2.The nano-Ag,nano-TiO2 and nano-SiO2 packing materials significantly inhibited the increase in browning index,MDA and relative electrical conductivity of loquat fruit during storage,enhanced the activity of POD,SOD,APX and CAT enzymes,while reducing the accumulation of O2·-hydrogen peroxide content.Among them,the anti-oxidation ability of the nano-SiO2 packing materials treatment is obviously superior to the other two nano-composite packaging materials;the post-harvest active oxygen metabolism of "Qingzhong" loquat fruit is superior to "Da Wuxing" loquat fruit.3.Compared with the control group,the nano-Ag,nano-TiO2 and nano-SiO2 packing materials treatment can significantly maintain the content of various soluble sugars,total phenols and total flavonoids in two loquat fruits,delay the decline of chlorogenic acid,chlorogenic acid and other major phenolic monomers content,also increase the DPPH free radical scavenging ability and hydroxyl radical scavenging ability of loquat fruit.This study found that compared with the other two kinds of nano packing materials,the nano-SiO2 packing materials treatment maintain higher level of the nutrient content;besides,the nutritional content of "Qingzhong" loquat fruit is generally higher than "Da Wuxing"loquat fruit.