Effects Of UV-C Treatment On Quality Maintenance And Antioxidant Capacity In Fresh-cut Carrot

Carrot is a kind of homemade vegetables which is delicious and rich of nutrient.In the consumption process of the market,the commodity added value of direct fresh carrot is very low.We can syncopate and process carrot in order to form convenient food.Fresh-cut carrot is Natural,health,fresh and green,so it has wide market prospect.Through the process of peel,cut and so on,the overall metabolic coordination of carrot is destroyed,which can cause a series of physiological and biochemical reactions.During the process of storage,transportation and sale,the changes of quality of carrots are different from other carrots which are well preserved.At present,UV-C treatment is widely used in Sterilizing ultraviolet radiation such as medical and health,food,water treatment and other industrial fields.It has advantages of high efficiency,harmless and no residues.The use of radiation in fresh-cut fruits and vegetables during storage processing,can effectively kill microorganisms,and will not damage the color,smell,taste,hardness and other sensory quality of fruits and vegetables,easier to be accepted by consumers.Research shows that,the UV-C treatment of fruits and vegetables is beneficial to the nutritional quality of fruits and vegetables to maintain and it can improve the antioxidant ability during storage.In these paper,I study the effects and mechanism of UV-C treatment on quality maintenance and antioxidant capacity in fresh-cut carrot,in order to provide theoretical underpinning for the preservation of fresh-cut carrot.The main results were as follows:(1)Segmentation treatment improved the whiteness value and the speed of microbial propagation in fresh-cut carrot during storage,but also increase the total phenolic content and the total carotenoid content,increase DPPH radical scavenging activity,ABTS~+ radical scavenging activity and hydroxyl radical scavenging.Shred processing is the best method,can most increase the content of total phenolic content,the total carotenoid content and oxidation resistance.(2)UV-C treatment had no effect on the change of white value of fresh-cut carrot during storage,but it had marked bactericidal effect on the microorganism on carrot surface.0.86 kJ/m~2 UV-C treatment effect on the quality of fresh-cut carrot are best kept,effectively promote the total phenolic content,the increase of the content of total carrot,delayed the decrease of Vc content.UV-C treatment group with the low dose of 0.21kJ/Dm~2 and 0.42kJ/m~2,the increase of total phenolic content and total carotene content is lower than the 0.86 kJ/m~2 treatment.UV-C treatment group with the high dose of 1.68kJ/m~2,the total carotene content higher than that of the control group in the first and second days,but on the third day and the fourth day,it is lower than that of the control group,high dose UV-C treatment showed the negat:ive effect to maintain the quality.(3)Compared with the control group,0.86 kJ/m~2 UV-C treatment increased the total phenol,the total carotene content and inhibited the decrease of vitamin C content during storage.Chlorogenic acid and Coffee acid are secondary metabolites of carrot.UV-C treatment significantly increased PAL,C4H,4-CL activity,secondary metabolism promote carrots,which benefits the increase of fresh cut carrots during storage of chlorogenic acid,Coffee acid content,and showed a rise in the total phenols content 0.86 kJ/m~2 UV-C treatment can keep higher SOD,POD,CAT and APX activity during the storage of fresh-cut carrot,further improve the DPPH radical scavenging rate and ABTS~+ free radical scavenging rate,delay the decrease of hydroxyl radical inhibition rate,inhibit the generation of superoxide anion,thereby further improving the antioxidant capacity of fresh-cut carrot.