I sauted some chopped up celery along with other veggies in making a soup, and then I pureed it all with my hand blender. While all the vegetable chunks were gone, the tiny fibrous veins of the celery (like tiny transparent splinters) didn't puree, and were inedible. They were just big enough to feel them on your tongue, but wouldn't dissolve if you chewed them. Somewhat ruined the eating experience.
This has never happened to me before, or at least, I've never noticed this before. Is it because my celery was a couple days old and not spanking fresh? What are my solutions? I suspect a strainer would take out only some of them. I suppose I could slice the celery so finely that the little veins (which run lengthwise, and I chop widthwise, as normal)would be so short as to hopefully be invisible.
Thoughts on this?