The Effect Of Different Storage Temperature And Cooking Methods On Quality Of Taraxacum Antungense Kitag

In this study, the dandelion (T. antungense Kitag.), picking from Shenyang Agriculture University, Liaoning Province. We choose healthy fresh leaves for different storage environment (15℃,4℃,-15℃), observe and measure dandelion sensory evaluation, weight loss and decay rate of degradation of chlorophyll, the accumulation of nitrate and nitrite law of the salt produced in order to determine the optimum storage temperature and time dandelion. Otherwise, through Dandong dandelion different cooking methods (blanching time and acceleration of the concentration of NaCl) and storage temperature for processing and analysis, to explore different forms of sensory changes to the degradation of chlorophyll, nitrate and nitrite content generation, provide a good theoretical basis for the development of dandelion postharvest best conditions for storage and cooking methods.1.Refrigerator (4℃) temperature condition is the best temperature for post-harvest storage dandelion.The dandelion in a refrigerated (4℃) processing, sensory evaluation value is relatively high, the decay rate and weight loss one week to maintain a low level during the week in storage. Refrigerated effectively delayed degradation, lower the content of malondialdehyde (MDA). In the fourth day of the arrival of the nitrate content maximum 275.764±2.49 mg· kg-1, does not exceed the safety standards for edible (432 mg·kg-1), nitrite in the reservoir 6 days more than 4 mg·kg-1 safety range.At room temperature (15℃) conditions, the value of sensory evaluation of lower leaves turn yellow rot quickly, higher MDA content in the first 3d maximum nitrate content of 298.32±0.40 mg·kg-1, the first nitrite 5 days to reach 4.18± 1.15 mg·kg-1.The frozen (-15℃) dandelion under normal temperature conditions after severe dehydration, just like the loss of marketability. Therefore, try to eat fresh dandelion, the dandelion best but refrigerated (4℃) post-harvest storage, preferably within five days of its completion in order to ensure the quality of edible the dandelion health.2.In terms about blanching time, dandelion best blanching time is 2min.In the blanching time of 2min, it minimizes the dandelion in chlorophyll content reduces the bitter taste, and blanching time in the other three levels in marked contrast to the extension of time and blanching also makes the dandelion Leaves nitrate (155.36 mg·kg-1) and nitrite (1.85±0.75 mg ·kg-1) was significantly reduced, blanching time is 0.5min time, although less in leaf color sensory loss, maintaining crisp taste called, but nitrate (208.31 mg·kg-1) and nitrite (2.22±0.75 mg·kg-1) and fresh the dandelion similar content, 1min in between, so the overall trend is:0.5min> 1min> 2min; after blanching the dandelion during storage at different temperatures found:cold (4℃) under the conditions of the blades in the 4d remains intact shape, nitrite in 1～2d still within the range of edible safety standards (4 mg·kg-1). At room temperature (15℃) under section 2d begins to soften, decay occurs when the first 3～ 4d, and with the smell, nitrites surge, completely inedible, and the first 2d, the content of nitrite has been exceeded. Therefore, the best blanching time of the dandelion is 2min, should be placed should be kept refrigerated choose, in order to ensure human health of eating recommendations in the 2d.3.Determine the maximum protection of chlorophyll added 0.1% NaCl with blanching the dandelion.In different concentrations of NaCl solution blanching dandelion can be made when compared with pure water hot drift inhibition of the enzyme is destroyed, not only to achieve the effect of color protection, but also supplemented by blanching dandelion and loss the salt, reducing the degree of cell damage, the concentration of nitrate increased along with added NaCl (0.1%> 0.3%> 0.5%) and gradually reduce its content of safety standards in edible (432 mg·kg-1) the range of the salt concentration has little effect on the deepening of nitrite content, no difference between treatments. Under storage conditions, after blanching with salt dandelion significantly better than unsalted state at room temperature (15℃) conditions, dandelion deterioration occurs in the case of the first 3～4d, a large concentration (0.3%, 0.5%) 1d in storage after processing reached a critical state range of edible nitrite. The refrigerator (4℃) conditions, when the blade 4d is still dark shape intact, nitrite at its 2～3d to reach edible range (4 mg·kg-1). Therefore, in the blanching solution appropriate to add nearly 0.1% NaCl is the best choice to ensure the health should be cooked the dandelion placed in a refrigerator (4℃) storage conditions.