Effect Of Several Edible Water Holding Substances On Increasing Rehydration Of Dehydrated Eggplant

Eggplant(Solanum melongena L.)is the fruit of Solanaceae and Solanaceae,widely cultivated in China.Eggplant is one of the common vegetables in our country,rich in nutrient,it can be cooked with various methods.At present,there are a variety of eggplant processing products on the market,and the dried eggplant is a common product.Because of low rehydration ratio and low rehydration rate,the edible quality of eggplant is limited,this problem also exists in other types of dehydrated vegetables.Rehydration ratio and taste are the direct factors affecting the quality of dehydrated vegetables,however,the relationship between pretreatment of vegetables and rehydration ratio improvement has not been sufficiently studied,while the processing methods and rehydration conditions have been stressed.The high rehydration property of Black Agaric is relevant to the Polysaccharide in Auricularia Auricula,konjac flour,hyaluronic acid,trehalose are all edible substances with water retention property.In this paper,konjac powder solution,hyaluronic acid solution,trehalose solution and black agaric liquid were added into the eggplant tissue by vacuum infiltration,to improve the rehydration ratio and taste.In this paper,using ordinary pressure heated-air drying processed dehydration treatment of eggplant slices,the physical and chemical indexes of eggplant slices such as rehydration ratio and texture characteristics were analyzed based on three factors study including permeate concentration,vacuum degree and evacuation time,which influences rehydration ratio of eggplant slices.The main results are as follows:(1)The technological parameters of vacuum permeation of konjac powder solution were determined.On the basis of single factor experiment,three factors were found to have significant effects on the rehydration of eggplant slices.The orthogonal test was carried out to select the optimum parameters for the vacuum permeation of konjac powder solution by selecting three parameters,the konjac powder solution concentration,the vacuum degree and the evacuation time: the konjac powder solution concentration was 40 mg/mL,the vacuum degree was 0.08 MPa,the evacuation time was 40 minutes,the effects of various factors on the rehydration ratio of eggplant slices were konjac powder solution concentration > evacuation time > vacuum degree.(2)The technological parameters of vacuum permeation of hyaluronic acid solution were determined.On the basis of single factor experiment,three factors were found to have significant effects on the rehydration of eggplant slices.The orthogonal test was carried out to select the optimum parameters for the vacuum permeation of hyaluronic acid solution by selecting three parameters,the hyaluronic acid solution concentration,the vacuum degree and the evacuation time: the hyaluronic acid solution concentration was 2 mg/mL,the vacuum degree was 0.09 MPa,the evacuation time was 35 minutes,the effects of various factors on the rehydration ratio of eggplant slices were hyaluronic acid solution concentration > evacuation time > vacuum degree.(3)The technological parameters of vacuum permeation of trehalose solution were determined.On the basis of single factor experiment,three factors were found to have significant effects on the rehydration of eggplant slices.The orthogonal test was carried out to select the optimum parameters for the vacuum permeation of trehalose solution by selecting three parameters,the trehalose solution concentration,the vacuum degree and the evacuation time: the trehalose solution concentration was 250 mg/mL,the vacuum degree was 0.09 MPa,the evacuation time was 30 minutes,the effects of various factors on the rehydration ratio of eggplant slices were trehalose solution concentration > vacuum degree > evacuation time.(4)The technological parameters of vacuum permeation of black agaric liquid were determined.On the basis of single factor experiment,three factors were found to have significant effects on the rehydration of eggplant slices.The orthogonal test was carried out to select the optimum parameters for the vacuum permeation of black agaric liquid by selecting three parameters,the black agaric liquid concentration,the vacuum degree and the evacuation time: the black agaric liquid concentration was 250 mg/mL,the vacuum degree was 0.085 MPa,the evacuation time was 40 minutes,the effects of various factors on the rehydration ratio of eggplant slices were black agaric liquid concentration > evacuation time > vacuum degree.(5)The effects of different fillers on the rehydration ratio and rehydration rate of eggplant slices were determined.The effects of different fillers on the rehydration ratio of eggplant slices were: hyaluronic acid solution > black agaric liquid > trehalose solution > konjac powder solution.The effects of different fillers on the rehydration rate of eggplant slices were: black agaric liquid > hyaluronic acid solution > trehalose solution > konjac powder solution.(6)The effects of different fillers on the texture characteristics of eggplant slices were determined: konjac powder solution had the most significant effect on the texture characteristics of eggplant slices,followed by trehalose solution and hyaluronic acid solution,and the black agaric liquid had minimal effect on the exture characteristics.According to sensory evaluation,the effects of different fillers were: konjac powder solution > black agaric liquid > trehalose solution > hyaluronic acid solution.