| UHP technology can keep the nutritional value of food well, it can also regulate food texture, extend shelf life of food, simplify food processing, energy conservation and so on. EHV in vegetable processing in multiple applications in sterilization areas, and the trial will be high pressure as a means of cooking vegetables, low temperature curing properties of their research EHV-eat vegetables and vegetable processing technology, as well as to predict the shelf life of vegetables ready to eat. The main results were as follows:Firstly, the single-factor experiments of pretreatment conditions ready to eat vegetable were carried out, including blanching time, temperature, color concentration, increasing concentration and increasing crisp crisp time, and to determine the optimal pretreatment conditions. The results were as follows:the optimal pretreatment conditions of cabbage Jia were blanching time1.5min, blanching temperature95℃; cabbage were crisp increase concentration2.5g/kg, time10min; purple onion were blanching time1.5min, blanching temperature85℃, nursing toner concentration0.2g/kg, crisp increase concentration2g/kg, time20min; carrot were blanching time of1min, blanching temperature90℃, crisp increasing concentration2g/kg, time30min; cabbage and carrot did’t need protecting color, and peppers and cucumbers did’t need pretreatment.Secondly, the single-factor experiments of the conditions of high pressure processing for ready to eat vegetable were carried out, including ultrahigh pressure and dwell time, but also to understand the effects of high pressure on vegetable sensory, nutritional indicators, the results showed that:the best high pressure processing conditions were cabbage450MPa,15min; purple onion400MPa,5min; carrots450MPa,10min; chili400MPa,15min; cucumber500MPa,15min. EHV could keep vegetable polyphenols in high rate, and increased its contained, foe example, chili400MPa, packing10min, polyphenols retention rate up to138%; EHV had little effect on POD activity but strong effects on microbes. Sterilization rate of five vegetables under optimal conditions of were above93%; against Vc relative to the heat treatment for the loss, of influence over the small, but the greater the pressure the greater the impact on the Vc, such as cabbage at600MPa packing10min, Vc retention rate was20.8%. In the determination of the quality of vegetables, three to five different cooking vegetables processing were investigated, including high pressure, stir and cook, determined by evaluating the product after oil rancidity high pressure treatment on the different treatment of sensory and vegetables, results were as followed:The people’s subjective assessment, combined with the determination of color and texture analyzer analyzer analysis showed that the high pressure treatment of RTE vegetables together in color, taste, hardness (brittleness) than other aspects of treatment has obvious advantages in terms of hardness and taste fried with results close to the UHP, stir-fried vegetables and color effects on larger; five vegetables by high pressure treatment, the product materials in the oil acid value and peroxide value does not exceed the state standards, so EHV-eat vegetables and vegetable products to meet the people’s quality requirements.By using colorimeter, texture analyzer, electronic nose, low-field magnetic resonance imaging and other equipments for the high pressure treatment and stir-fried carrot color, texture, aroma components, such as the measurement of water activity status analysis and summarizes the aging characteristics of carrots, the results showed that:the aroma components of UHP and stir cooking carrots, water activity state changes are similar, but the color and texture of high pressure over the carrots, stir well compared, in terms of sensory quality, high pressure cooking carrots after closer their original flavor, two cooking methods vegetables lethal effects on microorganisms are obvious, indicating high pressure low temperature cooking can make vegetables reach the "aging" state.We studied the pH, sensory, moisture content, fat rancidity, color, texture and other indicators of ready to eat cucumber which were stored at0℃,5℃,10℃conditions after EHV treatment, test results show that:the storage time instant with the growth of the cucumber, the moisture content of the other indicators in addition have occurred without a degree of deterioration, and as the key depending on the pH and the quality factor of the Arrhenius equation to predict the shelf life of cucumber are ready to be stored0癈61days,5℃can be stored56days,10℃can be stored53.3days, indicating that lower temperatures could not keep the ready to eat cucumber long, at10℃only saved53.3d, cucumber inappropriate use high pressure processing instructions, and other because of high pressure on the four vegetable microorganisms affect the characteristics and features of storable vegetables themselves, their shelf life of up to one year. |
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