Research On The Comprehensive Utilization And Processing Technology Of Xinjiang Junzao

In this study,supercritical extraction technology was used to extract the essential oils,sugar and pigments from Xinjiang jujube dates based on the differences in their solubility characteristics.The essential oil,jujube juice and pigment were extracted from the dates by techniques such as water leaching and alkaline extraction,and the corresponding products and process parameters were obtained.The comprehensive processing and utilization of jujube date fruit are realized,which improves the economic efficiency of the jujube industry.The main research content is summarized as follows.?1?Ziziphus Jujuba cv.Junzao was taken as a raw material in this study,and its essential oil was extracted using the supercritical CO₂ extraction technology.The extraction process of jujube essential oil was optimized by single factor and orthogonal experiments.Finally,the components of jujube essential oil were analyzed using the technology of headspace solid phase microextraction?HS-SPME?combined with gas chromatography-mass spectrometry?GC-MS?.The results showed that the optimum process parameters for supercritical carbon dioxide extraction of jujube essential oil are ethanol as a carrier,pressure 25 MPa,temperature 32�C,entrained flow rate 0.3mL/min,and extraction time 3 h.The extraction rate of jujube essential oil was 1.224%.A total of 68 components were detected by GC-MS,59 structural inferences,accounting for 91.737%of the total peak area,which were classified by acids,alkanes,ketones,esters,aldehydes and alcohols.Among them,caramel-scented maltitol and 5-methyl furfural,almond-odour benzoic acid and furfural,and milky-scented 3-hydroxy-2-butanone might be the main aroma components of the jujube essential oil.?2?Using the remaining residue of the above process?1?as the raw material,use the response surface method to investigate the optimized process conditions of ultrasonic-enzymatic synergistic extraction of jujube concentrated juice,and analyze the quality index of jujube concentrated juice.The results showed that when the extraction temperature was 55?,the extraction time was 4.0 h,the amount of enzyme added was0.42%,and the water addition multiple was 7.2 times.Under this process condition,the jujube juice yield was?74.21�0.42?%.Analysis of the quality index showed that the concentrated jujube juice suffered a certain loss of nutritional content,and the color and light transmittance of the juice also decreased.It was a reddish-brown semi-fluid and had good stability during storage.?3?The extraction process of jujube pigment was optimized by orthogonal test design using lye as solvent and the residual residue of the above?2?process as raw material.The results showed that the most suitable process conditions were 0.40 mol/L NaOH concentrations,75 ultrasonic temperatures,and ultrasonic time.In this process,the extraction rate of date pigment can reach 82.37%,and the date pigment can be extracted from the date.The pigment yield was up to 2.030%.It showed that it was feasible to continue the extraction of the pigment from the residue after extraction of the date juice.?4?The date pigment was purified from the pigment liquid extracted by the process described in?3?above using macroporous resins.The adsorption and elution effects of nine types of macroporous resins on date pigment were compared.The single-factor and orthogonal test was used to optimize the purification process of date pigment from macroporous resin.The results showed that the optimal process of the purification of jujube pigment is:pigment concentration 1.5mg/mL,flow rate of 1.5mL/The pigment adsorption rates were 77.36%at a filling height of 45 cm,and then 60%of the resin was used.Ethanol solution was eluted and desorbed at a flow rate of 1.0mL/min,and the purified pigment solution was clarified and bright,with a deep red color.Under the conditions,the color value of the pigment of dates increased from 3.33 to 23.13,and the purity increased by nearly 7 times.It is comprehensively shown that the extraction of jujube essential oil,jujube juice and pigments from red jujubes in sequence,the total utilization rate of red jujubes?de-cores?reached 83.387%,which can realize the high value comprehensive processing and utilization of red jujubes.