The Development Of Beetroot Healthy Tea

Beetroot has rich value of nutrition,especially its unique beet pigment and betaine,which has the physiological health functions such as antioxidant,anticancer,assisting blood pressure,relieving physical fatigue,etc.However,food research and development about beetroot is still in infancy,so the research and development of beetroot to produce function or health food must has good application value and good economic benefit.This experiment is about using red beetroot as a raw material to study on the process of beetroot healthy tea,through the process of pretreatment,heat,segmentation,protect color,dried.By single factor test and orthogonal test,we can obtain the best proportion of the composite color-protecting agent and the way of color-protecting.Hot blast drying,microwave drying,vacuum freeze drying were used to dry the beetroot,and the comparison of the there ways were carried on.The test also include that the determination and the analysis of nutrient composition respectively for fresh beetroot and dried beetroot products.We can evaluate the dried process through the rehydration rate test and the retention rate of nutrient composition.The results are as follows:(1)There kinds of color-protecting agent with better effect can be determined through single factor test(with beet pigment as retention index):phytic acid,ascorbic acid,citric acid.It can be obtained that the best proportion of the composite color-protecting agent by orthogonal test(with beet pigment as retention index)as follows:0.25%phytic acid,0.50%citric acid,0.20%ascorbic acid and the way of color-protecting is spraying.(2)Per 100 g of the edible part(out of peel and ends)of fresh-eating red beetroot contained:90.20 g of water,1.36 g of protein,0.03 g of fat,2.56 g of reducing sugar,0.94 g of crude fibre;mineral elements:0.29 g of potassium,0.15 g of sodium,22.10 mg of calcium,17.30 mg of magnesium,0.89 mg of iron,0.68 mg of zinc,0.43 mg of manganese,0.10 mg of copper;19.82μg of vitamin B2 and 12.38 mg of vitamin C;1.174 g of beetroot pigment and 0.102 g of betaine.Compared with several conventional vegetables,the red beetroot contains high iron and manganese,low calcium,magnesium,copper and zinc.(3)The best drying temperature of hot blast drying is 90℃ and the hot blast drying cost 10-11 h.The rehydration rate of the dried beetroot products of hot blast drying is 2.88,and the retention rate of beet pigment,betaine,vitamin B2,vitamin C are 58.53%,77.27%,87.67%and 9.29%.(4)The best drying power of microwave drying is medium-low fire(about 400 W)and under the intermittent drying mode,heating time is 8 s,intermittent time is 18 s,cycles of 50 times.The rehydration rate of the dried beetroot products of microwave drying is 3.43,and the retention rate of beet pigment,betaine,vitamin B2,vitamin C are 76.36%,65.17%,87.87%and 8.03%.(5)The vacuum freeze drying can well keep the quality characteristics of the beetroot,such as texture,flavor,appearance,etc,and the rehydration rate is 1.99 times of hot blast drying,1.67 times of microwave drying,the retention rate of beet pigment,betaine is as high as 98.73%,95.45%,92.86%and 98.73%.