I was sure that this was already being discussed somewhere, but my forum search was inconclusive. Please excuse if there's already a thread about this and feel free to integrate this post - and sorry for the trouble.

Reading many recipes lately that ask for raw onions being blended. I never done this because I heard this makes onions taste bitter, although some people regard this as a myth. What's your experience with that?

I'm inclined to go safe and many traditional recipes call for them to be boiled first, to make boiled onion paste, which makes much sense.

Still wondering about this.

Thanks!

I've used it before but can't recall exactly where (ie; in which recipe).  I've also used finely grated onion, which really gets the tears flowing and, before it broke, I used to use a Zyliss Food Chopper to literally pulverize onions to mix through burger patties and kebabs.  I can't say I've noticed any bitterness from either process, but the onion was used immediately. 

I found this though, which is basically saying that bitter sulfur based compounds can or do form after about 30 minutes.

https://www.foodprocessing.com.au/content/processing/news/why-onions-can-taste-bitter-43830118

This would suggest that if you make a raw onion paste and use it straight away, it should be fine.  Bitterness aside, should you store cut onions?

You can't believe everything on the internet!!!!

One thing I have read about onions is that you should not prepare them (raw) too far in advance or store cut onions.  It is rumored that cut onions are like a sponge to nasties and they soak up bacteria and toxins.  According to food scientists however, this is a falsehood and in fact onions contain elements that prevent the growth of bacteria and microbes.  However, you may end up with bitterness.

Thanks livo! There are dozens of recipes that suggest to just blend the raw onions with water or some additional ingredients before, and I have a hard time to believe that this could lead to such dramatic consequences without most people noticing. Some of the alleged science behind it made some sense though.