To remove the color from a dragon fruit image, you can use image editing software like Adobe Photoshop or GIMP. In Photoshop, you can use the 'Desaturation' tool or the 'Color Balance' tool to adjust the color settings. In GIMP, the 'Desaturate' filter can be applied. This process involves selecting the dragon fruit area and adjusting the color channels to convert the image to black and white or grayscale.