Study On The Preparation Of Marigold Straw Vinegar And Its Preservation Effect On Fresh Cut Flowers

The utilization of marigold straw with high-performance could relieve the environmental problems caused by waste straw and promote economic and social benefits.The study prepared straw vinegar with marigold straw as raw material at the ultimate temperature of 450?,550? and 650?.The yield,physicochemical properties,chemical composition,antioxidant activity and biological activity of vinegar was analyzed and the effect of concentration and pyrolysis temperature of the vinegar on the preservation of cut roses,carnation and transvaal daisy was evaluated.The results showed that:(1)The yield of the vinegar increased with temperature to a maximum and then decreased with the increasing pyrolysis temperature.The pH value of the vinegar was ranged 2.54?2.73,the density was 1.078?1.083;(2)The produced vinegar was a complex compound which mainly contained ketones(17.71%?20.76%?27.22%),phenols(21.54%?18.28%?15.37%),acids(4.24%?12.43%?12.90%),esters(8.77%?6.60%?5.78%),alcohols(11.76%?5.80%?5.52%),aldehydes(5.41%?13.89%?19.73%),furans(0.55%?9.74%?8.69%),etc.The content of phenolic,esters and alcohols in vinegar decreased while the amount of ketones,acids and aldehydes increased with the increasing pyrolysis temperature;(3)The antioxidant activity of marigold straw vinegar was better than that of oak wood vinegar.The germination and growth of mung bean seeds could be promoted by the marigold straw vinegar with appropriate dilution ratio.(4)The preservation of cut flower can be improved by the marigold straw vinegar liquid.The effects on fresh-keeping were different with the variation in pyrolysis temperature,dilution and flowers species.Compared with the control group,the vase life of the cut rose was prolonged by 1.2?6.2d when it was treated with marigold straw vinegar.The effect of preservation was more obvious when the vinegar was prepared at 550? and diluted to 500 times.The vase life of carnations and African chrysanthemum cut flowers could be prolonged by 0.4d and 0.5d,respectively when the vinegar collected at 550? pyrolysis temperature and diluted to 500 and 800 times.However,it would be negative effect if the vinegar was diluted to improper times.