Effect of drying methods on quality and energy consumption of okra crisp bar

In order to choose the best drying method for okra crisp bar,the effects of different drying methods including FID,AD,FD,MVD,FD-MVD,and AD-MVD on hardness,crispness,color,shrinkage,drying time,energy consumption as well as total flavonoid content,total phenolic content and polysaccharide content of okra crisp bar were investigated.The results showed that FD exhibited the highest retention of flavonoids,total polyphenol and polysaccharide,but poor hardness and the longest drying time and energy consumption.FID,AD and AD-MVD samples exhibited the content of flavonoids,total polyphenol and polysaccharide reduced in turn.Moreover,the hardness,color and shrinkage of the samples dried by the three drying methods were worse.FD-MVD and MVD samples showed higher retention of flavonoids,total polyphenol and polysaccharide next to FD samples as well as moderate hardness and better crispness. The differences of texture and nutrient content between MVD and FD-MVD dried samples were insignificant( p>0.05),but the drying time and energy consumption of FD-MVD were 40 and5 times that of the MVD samples,respectively. Overall,MVD may be a suitable industrial-scale processing method for okra crisp bar in consideration of better product quality and lower energy consumption.