How to avoid avocado in sushi rolls from darkening? We are making some avocado rolls and want to put them in the fridge for eating tomorrow. We will of course wrap them very well but how to avoid the avocado turning black or darkening?
You can try dipping it into acidulated water (water with acid added, either lemon juice or vinegar, or even a powdered vitamin c tablet).  This should delay the browning, but I am not sure it will last long enough to hold the rolls overnight.

You will have the additional problem that the nori will begin to soften overnight.

See also:  What&#39;s the best way to keep sushi fresh for the following day?