Effects Of Temperature And Modified Atmosphere Packing On Postharvest Storage Characteristics Of Hardy Kiwifruit(Actinidia Arguta‘Lv Mi No.1’)

Actinidia arguta is easy to soften when stored at room temperature.However,the kiwifruit is easy to suffer from chilling damage when stored at low temperature,which affects the fruit quality and commodity.Modified atmosphere（MA）of thin film is a simple and low-cost method of air conditioning storage,which can maintain the environmental conditions of high CO₂ and low O₂ by fruit self-respiration.Research shows that high pressure polyethylene（PE）film bag packaging can delay the aging process of fruits postharvest and reduce the cold damage.At present,there are few reports on the systematic research on the postharvest cryopreservation of kiwifruit.This test is to‘Lv mi’kiwifruit for material,in normal temperature storage for comparison to compare different storage kiwifruit quality change under the condition of low temperature and chilling injury symptoms,choose suitable for cold storage temperature.And then combined with different thickness of the PE bag packaging to explore the limit of gas refrigeration for‘Lv mi’the postharvest physiology and quality of the fruit.The results are as follows:1. Compared with storage at room temperature,cold storage at 0±0.5℃,1±0.5℃and 2±0.5℃can delay the decrease of fruit hardness and the transformation rate of soluble solids of‘Lv mi’fruit,so as to prolong the postharvest storage time.The storage effect of 0℃was better and the worst was 2℃.But the cold damage rate and decay rate of fruits were higher under three kinds of low temperature,especially the fruit loss was serious at 0℃,and the fruit loss was lighter at 1℃and 2℃with no difference.The storage effect of 1℃was better.2.0.05 mm PE bag packaging storage can significantly reduce O₂ and increase CO₂ concentration during the three different thickness（0.01 mm,0.03 mm,0.05 mm）.O₂ concentration of the 0.01 mm PE bag is the highest,next is the 0.03 mm.The two CO₂ concentration is lower but there is no difference,in which the gas environment formed in 0.03 mm PE bag（O₂:11.07%～13.35%,CO₂:2.33%～3.78%）is the most suitable for‘Lv mi no.1’fruit storage.3. The chilling symptoms of‘Lv mi no.1’fruit mainly includes hollowing flesh,browning of the skin,water-stained tissue and later lignified under the skin.PE bag packaging of 0.01 mm,0.03 mm and 0.05 mm can significantly reducing the cold damage rate and index of fruits,decreasing the occurrence of cold damage symptoms.Among which 0.03 mm PE bag packaging has the most significant effect.4. Compared to the comparison,different thickness of PE bag packaging can effectively inhibited‘Lv mi no.1’original fruit pectin and starch content,postponing hardness decreased,delaying the peak appearing time and values of respiration and ethylene,delaying fruit softening.And can effectively delaying the total phenol,Vc and soluble solids content.However,the excessively high concentration of CO₂ in0.05 mm PE bag damaged the membrane structure of the fruit,making the relative electrical conductivity and MDA content abnormal increase result in aggravating the decay.While 0.01 and 0.03 mm PE bag packaging can significantly reducing the weight loss and decay rate of the fruit.Especially 0.03 mm PE bag packaging effect is the best in maintain good fruit quality.In summary,low temperature storage can prolong the storage time of‘Lv mi no.1’fruit.Low temperature storage combined with PE bag storage can more effectively maintain the physiological characteristics and quality of fruit after harvest.