Application Of Microenvironment Air Conditioning Combined With Precise Temperature Control In Flat Peach Storage

Flat peach(Amygdalus persica L.)is a kind of fruit with high nutritional value.Flat peach not only contains a variety of vitamins,but also contains protein,calcium,iron,phosphorus and other nutrients,and iron content is on the top of the fruit.Flat peach has many functions.Eating flat peach for a long time can prevent anemia,relieve constipation,eliminate edema,promote blood circulation,promote blood circulation and remove stasis,which is widely welcomed by consumers.Flat peach is easy to soften and cannot bear storage,which limits the further development and utilization of flat peach to a great extent.For the development,utilization and further processing of flat peach it is urgent to study the storage of flat peach fruit.In this paper,the effects of different treatments on storage quality and volatile components of flat peach from Pinggu,Beijing were investigated in order to provide some reference for the development of flat peach industry.Precise temperature control technology is a new preservation technology,including freezing temperature storage and phase temperature storage.It can reduce the fluctuation range of storage environment temperature and reduce the harm to fruits and vegetables.Based on precise temperature control technology,this experiment used precise temperature control crisper and cold storage agent to create an ice temperature storage environment and a phase temperature storage environment.CK group and three treatment groups(ice temperature group 1,ice temperature group 2,phase temperature group)were set.CK group was packaged by ordinary foam box.Ice temperature group 1 was packaged by common foam box and cold storage agent.Ice temperature group 2 was packaged by precise temperature control crisper.The phase temperature group was packaged by the combination of precise temperature control fresh-keeping box and cold storage agent.The experimental results showed that the three treatment groups could control temperature fluctuation within a small range,and the phase temperature group(-0.21±0.06?)had the most significant effect.During storage,rot index and browning index of ice temperature group and phase temperature group were lower than CK group,flavor index was higher than CK group,and sensory quality of phase temperature group was the best.Compared with CK group,the other three treatments could inhibit the respiratory intensity and ethylene release of flat peach,reduce the loss of nutrients in flat peach and delay the decrease of hardness of flat peach.By SPSS,the highest score was in the phase temperature group,and the lowest score was in the CK group.It could be seen that the preservation effect of phase temperature group is the best.The main volatile components of flat peach were alcohols,aldehydes and esters,among which the relative content of aldehyde volatile components was the most important component of flat peach aroma.The volatilization of aldehydes could be reduced in the three treatment groups,and the effect of phase warming group was better than that of ice warming group.Therefore,precise temperature control technology was beneficial to cold storage and shelf preservation of flat peach at room temperature,and the phase temperature storage was better.Due to the different materials,thickness and properties of different plastic wrap,there are great differences in gas permeability.Flat peach was packed with different plastic film(ordinary plastic wrap,antifogging film,PE film and PLA film),and the effect of spontaneous air regulation was achieved by using different gas permeability.Ordinary plastic wrap was used as blank control group.The results showed that the plastic wrap of the three treatment groups could regulate the content of CO₂in the package at a higher level,and the content of O₂at a lower level,thus inhibiting the physiological activities of fruit and delaying its senescence.During storage,the decomposition and browning appeared first in CK group,and the decomposition index and browning index were the highest,and the flavor index was the lowest.The sensory quality of the three treatment groups was better,and the PLA membrane treatment group(20.10%O₂,0.98%CO₂)had the best sensory quality.Compared with CK group,the other three treatments could delay fruit senescence,inhibit fruit respiration and ethylene production,and reduce fruit nutrient loss.The overall score of CK group2,4.12%?5.53%CO₂)had the best sensory quality.The treatment groups using air conditioning components all had the fresh-keeping effect.Compared with CK group,the three treatment groups could reduce the consumption of nutrients to different degrees,and the contents of soluble solids,titratable acid and Vc were at higher levels.At the same time,the respiration of flat peach was inhibited and the rate of ethylene production was reduced.Compared with m MAP1 group and m MAP2 group,m MAP3 treatment group could delay fruit senescence,reduce fruit nutrient loss and inhibit fruit respiration.By SPSS,the comprehensive score was CK group1 as the screening index.The difference index during cold storage was respiratory intensity,while the difference indexes during normal temperature shelf were Vc content,respiratory intensity and relative conductivity.It could be concluded that m MAP3 group had a significant effect on inhibiting respiration,reducing Vc loss and delaying fruit senescence.The m MAP3group could effectively reduce the loss of volatile components of aldehydes.Therefore,m MAP3 treatment group had the best fresh-keeping effect.