I know that we should add campden before bottling wine. My question is, I need to add it 1 day prior to bottling or can I add campden and bottle right away. I am afraid of cork popping because if I remember correctly campden may release some gas.
"should add campden tablets before bottling wine" might be a bit of an exaggeration, though they can be beneficial in case you want an extra insurance that nothing will go wrong while your wine ages in bottles.
You can add the tablets as little as 30 minutes before you bottle. I wouldn't do it too long before bottling though, as that could also allow bad stuff to potentially re-enter your brew before bottling
You don't have to add Campden, only if your recipe calls for it or if you plan to age your wine and preserve it for a longer period of time. Remember that metabisulphite is naturally present in grape must and its purpose is to protect your wine from oxygen. The recommended amount of free SO2 in a wine is between 25mg/L and 50mg/L which can be tricky to acheive if you don't have the tools to measure it...
Now this being said, crushing a campden tablet and mixing it in a little water prior to adding it to wine shouldn't produce too much gas. However, if you wine still has some CO2 in suspension, you should degass it before bottling.
So, I wouldn't wait 24h, but I would mix it thourougly before bottling.
