Effects Of Electron Beam On Fresh Jujube And Development Of Jujube Jam

Fresh jujube is very popular because of its unique taste and rich nutrition.However,fresh jujube is very easy to be polluted by microorganisms during post-harvest storage,resulting in product decay and water loss and loss of commercial value.Therefore,the prevention and control of post-harvest diseases of fresh jujube is a vital part of the development of fresh jujube industry.Electron beam irradiation is a non-thermal food processing technology,which is an ideal choice for fresh food processing,because it can maintain the high quality of fresh food,prolong the shelf life and reduce the survival rate of microorganisms.In this experiment,Alternaria alternata and infected fresh jujube were treated by electron beam irradiation technology.The electron beam irradiation doses were 0-10 kGy and 0-5 kGy respectively to explore the sterilization effect and sterilization mechanism of electron beam irradiation technology on Alternaria alternata and the effect of electron beam irradiation technology on the quality of fresh jujube during storage.This experiment also studied a compound jam of fresh jujube to enrich the public’s cognition of fresh jujube products.Firstly,Alternaria alternata was treated with electron beam irradiation doses of 0,1,3,5,7 and 10 kGy to study the sterilization effect of electron beam on Alternaria alternata and the sterilization mechanism from the perspective of protein.It was found that the inhibition rate,morphology,egg white matter and nucleic acid leakage,catalase activity,superoxide dismutase activity,respiratory chain dehydrogenase activity,protein concentration,protein carbonyl content Protein sulfhydryl content,protein hydrophobicity and protein secondary stru cture have obvious effects.The greater the irradiation dose of 3-10 kGy,the greater the effect;The protein peptide chain of Alternaria alternata irradiated by electron beam was broken and polymerized.The results showed that 1 kGy electron beam irradiation could inhibit the growth of Streptococcus sativus.The higher the electron beam irradiation dose,the better the bacteriostatic effect.Secondly,0,1,3,5 kGy electron beam irradiation dose was used to treat the infected fresh jujube,and the effect of electron beam on the quality of fresh jujube was studied.It was found that there was no significant difference in the color,hardness,sensory evaluation,moisture,ash and hydroxyl radical scavenging ability of fresh jujube;The contents of total sugar and TSS in fresh jujube increased with the increase of irradiation doseat 0-3 kGy,and decreased at 5 kGy;The content of titratable acid remained unchanged in the irradiation dose of 1kGy and the control group,and increased slightly at 3-5 kGy;Vitamin Ccontent is inversely proportional to electron beam irradiation dose;The total phenol content,total antioxidant capacity and DPPH scavenging capacity were the highest at 0 kGy and 1 kGy,decreased at 3 kGy and the lowest at 5 kGy;Hydroxyl radical scavenging ability was directly proportional to the concentration of jujube samples,and there was no significant difference between different irradiation doses and hydroxyl radical scavenging ability.The results showed that 1 kGy electron beam irradiation could better maintain the quality of diseased fresh jujube.At the same time,the effect of electron beam irradiation on the storage period of fresh jujube was also studied.It was found that the hardness,color,sensory score and soluble solid content of infected fresh jujube decreased during the storage period,but the decrease range of 1 kGy was small;The order of incidence rate and lesion area was >1 kGy irradiation group >3 kGy irradiation group >5 kGy irradiation group.There was no significant difference in the weight loss rate of fresh jujube irradiated by 0,1,3 and 5 kGy electron beam during storage;The titratable acid increased during storage,and the fresh jujube fruit treated with 1 kGy irradiation resulted in a small TA value and increased slowly;Vitamin C was oxidized and decreased in storage,and the greater the electron beam irradiation dose,the more the loss of vitamin C content in fresh jujube;During the storage period,the total phenol content,DP PH radical scavenging rate,hydroxyl radical scavenging rate and total antioxidant capacity of the irradiation group were higher than those of the control group,and the 1 kGy irradiation group was the highest.The results showed that 1 kGy electron beam irradiation could better maintain the quality of diseased fresh jujube during storage.Finally,the green jujube compound jujube jam was developed.The optimum formula parameters of the compound jujube jam were as follows: concentration time 2 min,honey 30.00%,black fruit gland rib Sorbus 8.93 g,konjac powder 1.19%,citric acid 0.69%,and the soluble solid content of the compound jam was 31,which was greater than or equal to 25 in line with the requirements of the national standard;The contents of titratable acid,total phenol and vitamin C are 0.61 g / kg,5.94 mg / g and 186.00 mg / 100 g respectively,indicating that jam has certain nutrition and is suitable for consumers.