热风干燥温度对山楂粉品质的影响

Influence of Hot Air Drying Temperature on the Quality of Hawthorn Powder

为了研究不同热风干燥温度对山楂干燥产品品质的影响。以鲜山楂为原料,设置不同的温度梯度,以干燥时间、干燥速率、休止角、堆积密度、分散性、持水性、总酚含量、总黄酮含量及抗氧化活性为指标,考察不同温度下得到的山楂粉品质。结果表明:在干燥温度为70、80、90、100、110℃时,山楂粉到达干燥终点的时间分别为200、160、140、120、80 min,干燥温度越高,所需时间越短。随干燥温度的升高,休止角逐渐增大,堆积密度先降低后升高,持水性逐渐降低。80℃下得到的山楂粉总酚含量最高,为5.415 mg/g,且其对1,1-二苯基-2-三硝基苯肼(1,1-Diphenyl-2-picrylhydrazyl,DPPH)自由基和2,2-联氨-双-3-乙基苯并噻唑啉-6-磺酸(2,2’-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基有较高的清除率,总还原能力与其他组相比较高。综合结果可知,热风干燥温度为80℃得到的山楂粉中总酚及总酮的保存率较高,且品质最好。

To study the effect of different hot air drying temperatures on the quality of dried hawthorn products.Using fresh hawthorn as the test material and setting different temperature gradient,with drying time,drying rate,resting angle,packing density,dispersibility,water holding capacity,polyphenol content,flavonoids content and antioxidant activity as evaluation indicators to investigate the quality of hawthorn powder at different temperatures.The results indicated that at the drying temperature of 70,80,90,100,110℃,the time to reach the drying endpoint for hawthorn powder was 200,160,140,120,80 min,respectively.The higher the drying temperature,the shorter the time required.With the increase of drying temperature,the angle of repose gradually increased,the packing density first decreased and then increased,and the water holding capacity gradually decreased.The hawthorn powder obtained at 80℃had the highest content of polyphenols(5.415 mg/g),also had a high clearance rate for 1,1-diphenyl-2-picrylhydrazyl(DPPH)and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)cation free radicals,and had a higher reduction ability compared with other components.The comprehensive results indicated that the hawthorn powder obtained by hot air drying at 80℃ had higher preservation rates of polyphenols and flavonoids with the best quality.