Investigation On The Quality And Technology Condition Optimization Of New Carrot Pickles Using The Positive And Negative High-pressure Rapid Prepared Technique

The southwest of China is currently the main gathering place of pickles. Sichuan pickles gotextremely high reputations because of its unique flavor. However,theproduction of Sichuan characteristic pickles production is still mainly using the traditional production method of salting before fermentation, which has many disadvantages. This research is to solve existing difficult problem about the vegetable raw material of long-term storage, high salt content and long fermentation period when using the current technology of Sichuan pickles. Therefore aiming at the present situation, a method that air drying of three stages combined with positive and negative high pressure infiltration technology for preparing pickles should be study to achieve these aims including long-term storage, low-salt pickles,quick fermentation, uniformity of product quality, conduciving to large-scale,industrialization and standardizationof production.Firstly, according to the result of fuzzy sensory evaluation was measured by single factor experiment combined with response value, quadratic regression model about influence factor was established by Box- Behnken experiment design and response surface analysis to analyze the data. The best production conditions for the new carrot pickles was obtained that the amount of additives about fermentation was 6%, the amount of liquid flavoring concentrates was 70%, the concentration of salt was 9.2%. Under the optimized conditions,the new carrot pickles sensory score was 91.2.Secondly, usingthe method of three-stage air drying to create new carrot pickles. Based on the result of single factor experiments, the orthogonal experimental study was adopted and sensory evaluation of the product was evaluated. We got the optimum airdrying conditions thatwas the first stage air-dried at 25?, time of baking was 3 h; the second stage air-dried at45 ?, time of baking was 3 h; the third stage air-dried at 55?, time of bakingis 2.5 h. In this operating model, sensory evaluation of the new carrot pickleswas close to the score of 93,which was relatively better than that of constant temperature air drying.Thirdly, through thesingle factor design and orthogonal experiment of positive and negative pressure infiltration, the optimum conditionswere that reactionpressure was 1.5MPa,the time of positive and negative pressure was 15 min, and temperature was selected at 30?.Fourthly, the physical and chemical indicators of three different pickles, including the new carrot pickles, the commercially bagged pickles, the fresh pickles of market, were analyzed and compared. Theresearch showed that the nitrite content of new carrotpickles was far below that of the national standard, and the nitrite content of the commercial packaged pickles was higher than that of the sold fresh pickles. The content of total acid in descending orderwere: the commercial packaged pickles, the sold fresh pickles, the new carrot pickles.After a longerperiod of fermentation time, the content of amino nitrogen in the pickleswas onthe high level, and the highest amount in the commercial packaged pickles. Besides, new carrot pickles in lowest levels. the highest amount of Vc content was founed in new carrot pickles, the followed by the selling fresh pickles, the lowest one was in the commercial packaged pickles.Fifthly, the main aromas of the three pickles were analyzed and identified. The 45 volatile substances were detected in new carrot pickles, and 23 volatile substances were detected in commercial bagged pickles. While 37 volatile substances were detected in sold fresh pickles. The pickles contained aroma components include alcohols, alkenes, esters,aldehyde, ketone, acids and trace alkanes. The new carrot pickles were able to preservearoma components of pickles. Due to the differences of production methods and preservation, the component and the content of aroma of these three pickles had differences. Meanwhile, the three kinds of samples had their own unique flavor. Commercial bagged pickles contained a great amount of volatile acids, and Commercial fresh pickles had the flavour of bouquet.While new pickles had a pleasant smell of pineapple and clove, so it got more favour from consumers.Finally, pickles production line is designed to focus on the arrangement of the equipment,the design of edinstallation. Production processes using advanced technology and equipment,the productivity has been improved, reducing manual labor consumption.