Certain combinations in high-powered blenders can end up frothy, foamy, or with a mousse-like texture. Sometimes it’s appealing, but other times you really don’t want all the extra air bubbles whipped into your smoothie or soup. You can minimize bubble formation by blending for less time, but sometimes you want to get a really smooth consistency by blending for longer.
Here’s a somewhat surprising trick to remove bubbles and eliminate froth: turn the blender to its lowest setting and then slowly ramp it up until the top of the liquid just starts to circulate. In some cases the lowest speed is still too fast, in which case you can put it to the lowest speed and repeatedly briefly pulse it on. As you run it at this low speed, you will see bubbles coming out in the center. It’s a bit hard to describe, so here’s a video of bubbles coming out of a pumpkin pie smoothie:
You’ll notice at the end of the video the liquid starts to circulate faster because it’s not as thick due to the loss of of bubbles/foaminess. If you want to keep removing bubbles you can turn down the speed so that it’s just barely circulating again, and continue until you don’t see any more bubbles coming out. It works surprisingly well. I’ve compared the volume before and after, and I’ve seen a half cup of air come out of a four-cup mixture!