Analysis Of Compositions And Heavy Metals Of Four Wild Vegetables In Nanjing Suburb

Wild vegetables are widely distributed,with strong adaptability and resistant to cold or drought enviroments with unique taste and rich in nutritients.Especialy the contents of some vitamins and minerals beneficial to human health are higher than the general cultivated vegetables.Therfore,wild vegetables are precious resources that favored by consumers.It is an effective way to mountain farmers out of poverty to get rich by utilization of wild vegetables.In this paper,four wild and cultivated vegetables including chrysanthemum,cedar,malan head and dandelion were collected in fangsha area of Nanjing.The main nutrients and heavy metal content were analyzed.Meanwhile,the changes of main nutrients of these wild vegetables affected by different cooking methods were studied,which provides the basis for development,utilization and proper consumption of wild vegetables.The main results are as follows:(1)Natural wild this compared with artificial cultivation of the four kinds of wild vegetables,soluble sugar content is obviously much lower,crude fiber,protein,fat and vitamin C content,there were no significant differences between natural wild and artificial cultivated wild vegetables.(2)The mineral elements content of four kinds of wild vegetables and artificial cultivation of similar elements content in vegetables,mineral elements content were higher than in the wild vegetables cultivation of vegetables.(3)Four kinds of wild vegetables all contains a certain amount of heavy metals,including copper and lead concentrations are relatively high.And natural wild vegetables compared with the artificial cultivation of wild vegetables,heavy metal content is much obvious,it is more than safe to eat.(4)Boiled part on carbohydrate and protein hydrolysis,impact on fat is not big,but can make the water-soluble vitamins and minerals,soluble in water.Steaming effect on nutrient elements and boiling are similar,but the minerals will not lost by steam.Fry for all nutrients have different degrees of damage,including protein serious degeneration due to high temperature,oil hot polymer and lipid peroxide content increased;Microwave cooking because of the rapid heating,shorter time,relative to character.