Effects Of Preservation Methods On The Preservation Effect Of Fresh-cut Jackfruit

Artocarpus heterophyllus Lam is a typical tropical crop.At present,the yield of jackfruit in China is more than 50,000 tons.Due to the relatively concentrated mature harvest period(July~ September,high temperature and high humidity season),it is easy to be contaminated by microorganisms.Jackfruit pulp was rich in sugar,active ingredients,vitamins and other nutritional elements,poor storage performance,room temperature 1~2 d that is rotten,to the sale,transportation and consumption of many inconvenience.Therefore,in view of the above problems,this paper studies the effects of different preservation methods on the preservation effect of fresh-cut jackfruit to provide technical support for its industry.The main findings are as follows:(1)(1)By studying the effects of ascorbic acid,sodium alginate,red algae gum and konjac powder on the color,hardness and total acid content of fresh-cut jackfruit,the optimal coating material concentrations were determined as follows: ascorbic acid 0.05%~0.15%,sodium alginate 0.5%~1.5%,konjac powder 1.0%~2.0%.After 15 days of coating,0.10% ascorbic acid L* value,total acid,hardness and reducing sugar were higher than those of the blank group(7.82%,15.79%,75.53% and 79.27%,respectively).The weightlessness rate was 81.04% lower than the blank group.The total number of colonies was 1 order of magnitude lower than the blank group.The results showed that coated jackfruit pulp was up to 15 d,and ascorbic acid had good preservation effect among the 4 commonly used preservatives.(2)Through the study of(4±1 °C)atmospheric pressure,vacuum,nitrogen filling three kinds of packaging methods on the sensory quality,color,texture and other indicators of fresh-cut jackfruit,the results show that the nitrogen-filled packaging can better maintain the fresh cut jackfruit The sensory quality and delayed browning were observed.On the 15 th day,the L* value,hardness,elasticity,cohesiveness,chewiness and reducing sugar were 4.41%,12.08%,5.95%,41.82%,34.86% and47.44%,a* value,b* value and total acid were 11.28%,4.62% and 58.97% lower than the normal pressure group.The total number of colonies was 3000 times lower than that of the blank group.On the 18 th day,the volatile components of the nitrogen-packed esters were encapsulated.It is 28.73% higher than atmospheric packaging.(3)Through the study of(4±1 °C)PE,PET and aluminum foil three kinds of packaging materials on the sensory quality,color,texture and other indicators of fresh-cut jackfruit.Due to its high barrier property,aluminum foil packaging can effectively alleviate the quality deterioration of jackfruit.On the 18 th day,L* value,b* value,hardness,elasticity,cohesiveness,chewiness,total acid and reducing sugar are higher than PE.Groups 8.01%,0.11%,9.09%,11.09%,5.95%,41.82%,4.88%,54.10%,a* value was 6.11% lower than that of PE group,the total number of colonies was one order of magnitude lower than that of blank group,and aluminum foil packaging on the 18 th day The main volatile component esters were 26.91% higher than PE packaging.The results show that the packaging material preserves the pineapple pulp for up to 18 days.Among the three conventional packaging materials,the aluminum foil packaging has a good fresh-keeping effect.(3)Through the intuitive comprehensive balance analysis of multi-index orthogonal test,the fresh-cut jackfruit fresh-keeping preparation process is as follows: ascorbic acid concentration is 0.10%,packaging method: vacuum,packaging material: aluminum foil.The verification experiment was carried out.On the 12 th day,the brightness value was 72.66,the soluble solid value was 23.68%,and the hardness value was 382.65 g,which was greater than any treatment group in the orthogonal test,which further confirmed the reliability of the orthogonal test results.(4)According to comprehensive analysis by direct comprehensive balance method of orthogonal test of coating film,packaging method and material,the fresh-cut jackfruit preservation process is as follows: ascorbic acid concentration is 0.10%,packaging method: vacuum,packaging material: aluminum foil.The theoretical fresh-keeping time can reach 20 days,and the experimental results show that the luminance value measured on the 20 th day is 72.66,the soluble solid value is 23.68%,and the hardness value is 382.65 g,which is better than the theoretical data of the orthogonal test.(2)The effects of physical static freezing on the sensory quality,color and texture of fresh-cut jackfruit pulp were studied.Investigate the salt and sugar water soak as a pre-treatment and other factors.On the 18 th day,the L* value,a*,b* value,hardness,elasticity,cohesiveness,chewiness,total acid,reducing sugar and soluble solid content of 5% salt water treated jackfruit were 60.19,3.59,40.59,respectively.449.41 g,0.89,0.91,112.54,0.29%,2.14%,17.99%.The aroma of the sensory aroma blank group,1% syrup and fresh jackfruit are closer.The results showed that 5% salt water had a good preservation effect when stored for 18 days.This study aimed at exist in the process of processing and storage of fresh cut jackfruit Browning and decay,texture soften the problem of quality deterioration,provide different preservation technology,to solve the origin of farmers with more,overcapacity,fresh cut raw material drug problem and to explore the method of preservation of jackfruit,so as to cut fresh jackfruit preservation technology and provide theoretical basis to rot.