Study On Controlled Freezing-Point Storage Of Quality Of Sweet Corn

Sweet corn has rich value of nutrition, while it could storage for only 2or 3 days in the room temperature. In order to extend the shelf life of the sweet corn, this paper take the sweet corn (Zea mays L Saccharata Sturt) as material and study on controlled freezing-point storage of quality. In order to study the influences of different controlled freezing point storages on the quality of sweet corn, three group trials were conducted: controlled freezing-point storage without package (control), controlled freezing-point storage with package, and controlled freezing-point storage after 5 days at 4℃low temperature acclimation. The respiration rate, relative electrical conductivity, Drip loss, freezing injury rate, water-soaking index, weight loss, total sugar, moisture contents and sensory were analyzed.The main results of this research can be concluded as follows:1. through 4℃low temperature acclimation, a series of physiological changes to adapt to low temperature, cell concentration rise and membrane resistance to cold temperature abilities can be enhanced , the probability of the damage occurrence reduce, and extend its shelf life.2. Packaging can maintain a high relative humidity storage environment to reduce water loss caused by transpiration, so that corn kernels, husk and silk can keep a good shape and appearance.3. Evaluating the 7 sensory indexes of sweet corn of color, smell, sweetness, flavor, brittleness, roughness and total score. The results showed, sweet corn, through 4℃low temperature acclimation, the corn ears kept a good color and taste, furthermore, the color decline, flavor loss, sweetness drop, brittleness drop, roughness decline and total score of corn were 19.28%, 31.11%, 17.09%, 15.56%, 23.02% and 20.80% and 20.45% during 20 days storage, respectively. Compared with the control, the above-mentioned 7 indexes decreased by 18.55%, 13.33%, 9.45%, 19.12%,15.09%,4.80% and 13.07%, respectively.4. The respiratory rate of sweet corn in -1℃was only 13±5CO2 ml*·kg^-1·h^-1, only 5.4 of that in 20℃. The results showed, sweet corn, through 4℃low temperature acclimation, the corn ears kept a good color and taste, furthermore, the freezing injury rate, weight loss, relative electrical conductivity increase, drip loss, sugar loss and moisture loss of corn were 20%, 2.84%, 63%, -6%, 12.41%, 0.34%, during 20 days storage, respectively. Compared with the control, the above-mentioned 6 indexes decreased by 30%, 11.84%, 63%, 20%, 2.15% and 1.66%, respectively.