If Li Production Safety Key Technologies And Technology Research And Development,

Based on the traditional techniques of plum preserves, a series of technologies such as desalination of intermediate product, vacuum sugar infiltration, microwave-drying technology and the application of sodium dehydroacetate to the traditional process of plum preserves were studied in our research.Study showed that in the process of desalination, the speed of the desalination was affected by the different ratio of sample to water, temperature and time. A model curve of desalination was established to enable the manufacturer to find the proper desalination condition according to the salinity of the product acquired , or to calculate the salinity of the desalted plum from the given conditions. The model had high potential to be applied to the industry.The single factorial and orthogonal experiments found that the significance order of the factors affecting the speed of sugar infiltration was as follows: suagr solution > vacuum-break time > the temperature. The concentration of sugar solution had the most significant effect. Vacuum -breaking time also had great effect on the sugar infiltration of plum preserves. Since plum fruit was firmer than most of other fruits, the vacuum condition in the sugar infilteration need to be broken freqnently to creat the pressure difference to promote infiltration. The effect of infiltration temperature in this experiment was not significant, which maybe caused by the restriction of experiment scope. The optimum infiltration conditions were: 60%of sugar solution,. 10min of vacuum-breaking time, 40℃ of the infiltration temperature.The study of microwave-drying showed that heating time and intermission time had very important effect in the speed of the intermissive microwave-drying, while heating time had more significant effect than the intermission time. By selecting different heating time and intermission time and by controlling the drying speed, the drying quality as well as energy efficiency can be optimized.In addition, the effects of sodium dehydroacetate on the microbe growth under different sugaring temperatures (5, 15,25℃, selected as tipical temperature condition in different seasons) in the traditional process of Chinese plum preserves were studied. The results showed that the inhibitory effect of sodium dehydroacetate was much stronger than that of sodium benzoate.Compared with the traditional products, the vacumm infiltriton products had higher rigidity,elasticity and glutinosity, indicating that the new process have a wider range of texture adjustment.