Changes Of Functional Substances Of Fresh-Cut Cauliflower During Process And Storage

Cauliflower is rich in vitamins,trace elements and other nutrients,but its monomer volume is large,so it's inconvenient to cook food directly in daily life.It is suitable for processing fresh-cut vegetables,and is widely planted in Northeast China.In order to find an efficient and environmentally-friendly storing technology of fresh-cut cauliflower,this paper studied the storage technology of fresh-cut cauliflower from four aspects of heat treatment,color fixative,package and temperature.By measuring the quality during storage,the best storage conditions were determined and the aroma components were analysed.The main results were as follows:1.With fresh-cut cauliflower as experimental material,we simulated three heat treatment different temperatures(40?,50?,60?)of fresh-cut cauliflower storing for 3 minutes,and determined the storage quality at 4?of fresh-cut cauliflower regularly.The results showed that heat treatment with 40?for 3 min could alleviate the degree of decay and membrane lipid peroxidation of fresh-cut cauliflower,reduce its respiratory intensity,and inactivate the activities of polyphenol oxidase and peroxidase,so as to delay the browning of fresh-cut cauliflower and improve the storage quality of fresh-cut cauliflower.2.With fresh-cut cauliflower as experimental material,choose different color fixative in the storage of fresh-cut cauliflower browning degree and polyphenol oxidase activity.The influence of the exploring composite stabilizer color-protecting impact on storage quality of fresh-cut cauliflower.The results showed that the optimal color fixative agent compound concentration was 0.26%citric acid,0.21%ascorbic acid and 0.15%Ca Cl2.Under this conditions,the browning degree of fresh-cut cauliflower was 10.37 and the activity of polyphenol oxidase was 0.55.The color protection effect of the compound color protection agent on fresh-cut cauliflower during storage was better.3.With fresh-cut cauliflower as experimental material,we simulated four common packaging methods(0.01 mm PE film,0.4 mm PET crisper,0.06 mm LDEP freezer bag and 0.6mm PP tray covered with 0.01 mm PE film)of fresh-cut cauliflower were simulated at 4?storing,and the storage quality of fresh-cut cauliflower was determined periodically.The results showed that the weight loss of cauliflower stored in crisper could be alleviated,and it had good chewiness,the content of soluble solids and reducing sugar could be well maintained,And Principal component analysis revealed that the comprehensive quality of fresh-cut cauliflower exhibited a sharp decrease after 9 days of storage,while which treated by 0.4 mm PET crisper comprehensive score was 0.21,could prolong the shelf life of fresh-cut cauliflower.Therefore,0.4 mm PET crisper is a promising method to maintain the quality of fresh-cut cauliflower.4.With fresh-cut cauliflower as experimental material,we simulated three different temperatures(0±1?,4±1?,25±1?)of fresh-cut cauliflower storing,and determined the storage quality of fresh-cut cauliflower regularly.The kinetic model fitted with the Arrhenius equation was used to construct the shelf life prediction model on index storage quality.The results show that low temperature can inhibit the increase of weight loss rate and decay rate significantly,slow down the decrease of hardness and ascorbic acid content,and slow down browning degree,also reduce malondialdehyde content,and delay the peak value of Polyphenol oxidase and Peroxidase.The shelf life prediction model has high accuracy,the fitting correlation coefficient R~2 were all above 0.9,and the relative errors were within±10%.5.To explore the volatile aroma components of fresh-cut cauliflower by GC-MS.The results showed that the optimum storage conditions changed the volatile aroma components and content of fresh-cut cauliflower,decreased the type and relative content of hydrocarbons substances,the relative content decreased by 15.65%,but the types and relative contents of aldehydes,ketones,phenols and esters increased by 7.91%,4.65%and 1.41%respectively.In general,the treatment enriched the volatile aroma components of fresh-cut cauliflower,and increased its content.