本研究以新鲜苦瓜为原料，分别采用热风与远红外两种干燥方法在不同温度条件下（40 ℃、50 ℃、60 ℃、70 ℃、80 ℃）制备苦瓜全粉，比较了两种不同干燥方法对苦瓜的干燥特性、色泽、Vc含量及保留率、皂苷含量等品质指标的影响。结果表明：热风干燥与远红外干燥的苦瓜全粉品质随温度的改变而呈规律性变化，随温度的升高，干基含水量下降速度加快，干燥时长缩短；与新鲜苦瓜相比，制得的苦瓜全粉色泽随温度升高L值(明度)与b值（+黄，－蓝)变小，a值(+红，－绿)变大；Vc含量及保留率也随温度的升高而呈现先升后降的趋势，并在60 ℃达到峰值；皂苷含量随温度升高而降低。同一温度条件下，热风干燥效果明显优于远红外干燥。综合比较，热风干燥60 ℃条件下，干燥时间短，能耗损失低，苦瓜全粉色泽呈现好；Vc含量为63.42 mg/100 g，且保留率高达69.31%，皂苷含量为1.74%。

Fresh bitter gourds were powdered using hot air and far-infrared (FIF) drying methods at different temperatures (40 ℃, 50 ℃, 60 ℃, 70 ℃, and 80 ℃). Quality indicators such as drying characteristics, color parameters, content and retention rate of Vc, and momordicoside content, were compared. The results showed that all indicators exhibited regular changes with variations in temperature. As temperature increased, the moisture content decreased faster and drying time was shortened. Compared with fresh bitter gourd, values L (lightness) and b (+ yellow, - blue) of the color parameters of the powder reduced, while value a (+ red, - green) increased as the temperature increased. Vc content and retention rate increased at first and then decreased with increasing temperature, reaching a peak at 60 ℃. Additionally, momordicoside content decreased as temperature increased. Hot air drying was found to be more effective as compared to FIF drying at the same temperature. In summary, when hot air drying at 60 ℃ was used, drying time was shorter, energy loss was low, and the bitter gourd showed satisfactory color. Additionally, the retention rate of Vc reached as high as 69.31% with a content of 63.42 mg/100 g and 1.74% momordicoside.

农业部公益性行业科研专项（201303079）