Sous vide whole salmon at what temperature?

If you want to keep the texture of slow-cooked food at 50°C, then depending on your religion and AA status, you might add 1 glass of white wine per Kg of salmon.

Disadvantage: the alcohol will not evaporate at all!

Advantage: The alcohol will not evaporate at all and give additional flavour to the salmon!

Personally, I use 25% fresh dill (leaves only) and 75% white wine and as alcohol is a natural disinfectant, cooking longer times at 50°C is absolutely no problem but obviously, this is not a dish for kids... Afterwards, I use the little wine that was not soaked up by the salmon to create a wine sauce that goes on top of the fish. I use the dill stems here and remove them before serving. In the sauce, the wine does get up to boiling point.

One last tip: don't use the cheap cooking wine, but a good wine that you could serve to your guests too. I personally use a Pouilly-Fuissé to slow-cook the salmon in and to serve at the table...

Whole salmon simply isn't a great candidate for low temp cooking in a water bath. While you can achieve excellent results with portioned salmon, cooked at 50C for well under an hour, this timing is impossible for a whole fish. It would be necessary to cook much longer. The problem is you would probably have to cook the whole fish for a couple of hours. This causes the enzymes to break down the flesh and you get a mushy, unpleasant product. Alternately, as you experienced, raising the temp to speed things up results in a dried out product.

I would choose a different cooking technique for the whole fish...or portion your salmon into steaks or fillets and look here: http://www.chefsteps.com/activities/sous-vide-salmon--2

Your temperature is inevitably going to dry the salmon out - it's too high.

As to whether it's possible to sous-vide whole salmon, I'm about to find out. But experience with smaller fish suggests the time goes up but the results can be very good.

There are some web resources which help calculate cooking times as size increases.

I suggest you try lower temperatures on smaller pieces to find what you like.

If it's 50C - which tastes dry to me - cook at 50C

I cook at 43C but that's about as low as I'd go.

Your temperature is too high, that's why it's dry.

You can cook a whole fish, but lower the temperature. Longer time at lower temperature has the same sterilising effect as higher temperature and shorter time btw.

I cooked a whole salmon trout in a court-bouillon at around 45C for a little over an hour and it was very juicy.

Determine your preferred temperature by testing fillets for shorter times.