Thickening a runny smoothie is quick and simple -- all you need to do is add more of whatever thick or solid ingredients you've chosen for your recipe. Blending in fresh or frozen fruit, vegetables, yogurt, soaked chia seeds or even ground oatmeal thickens smoothies while giving them a richer flavor. Blenders vary in power and sturdiness, so consult your owner's manual to determine how much of your solid ingredients to add at a time.
Preparing Solid Ingredients
If you're using something solid to thicken your smoothie, such as fruit, vegetables or ice cubes, cut or smash it into small pieces before adding it to the blender. This makes it easier for the blender blades to grind the ingredient smoothly and thoroughly. The average blender needs a little help with ice cubes, so crush them in a bag before adding them to your smoothie. Thick, viscous ingredients like yogurt or soaked chia seeds need no special preparation.
Blending Ingredients Evenly
Before adding the new ingredients, start the blender on a low to medium speed to create a vortex in the jar, pulling the runny smoothie downward onto the blades. Open the hole in the blender lid and slowly add the thick or solid ingredients, ice cubes last. Wait until the blades have ground each portion of solid ingredients thoroughly before adding more. If necessary, close the hole in the lid and increase the blender speed to get an even consistency. Stop blending occasionally to scrape down the sides of the jar and stir the contents.
Adjusting for Blender Type
If your blender jar opens at the bottom, by the blades, instead of at the top, pour the runny smoothie into a separate container, add your solid ingredients to the bottom of the blender jar and pour the smoothie back in on top of them. When you turn the jar upside down to attach it to the blender mechanism, having the heavier ingredients on top helps the blades blend the smoothie more evenly. If your blender has a "pulse" function, use it to break up any stubborn pieces that won't incorporate when you run the blender at a steady speed.