There’s no straight answer for if you can put food in the sous vide water bath while it’s preheating. It matters less for longer cooking times and has more of an impact for shorter cooking times.
Whichever you end up choosing, just remember that the cooking time starts when the water is at the target temperature and the sous vide bag is in the water. Read on to learn more.
Do You Have to Preheat Water for Sous Vide?
Sous vide is all about precision cooking at the exact recommended temperature for a particular food.
The whole concept is based around bringing a water bath to the target temperature to get the perfect cook.
The purpose of the most commonly used type of sous vide machine, immersion circulators, is to heat up and circulate the water so that it stays at this exact temperature throughout the cooking process.
By introducing food too early into the water bath, you can forgo some of this precision.
The food is taken through all temperatures as the heat increases during the preheating stage, which results in inconsistent cooking.
For foods that require shorter cooking times (eg., 1-2 hours), waiting for the water to preheat is more important because you’re more likely to get less precise results.
In comparison, for longer cooking times (eg., 5 hours), placing food in too early while the water is still preheating has less of an impact because the food has more time to stabilize and cook at the correct temperature.
Also, smaller containers take less time to heat up, so preheating isn’t critical. However, for large containers (like a large stock pot or cooler), they take longer to heat up, so it’s better to wait.
All in all, for anything that you cook sous vide, cooking time recommendations start when the water has reached the recommended temperature for that type of food, and you drop the bag in the water bath.
How Long Does Sous Vide Take to Preheat?
It depends on what your target temperature is and how much water you have to heat up.
Higher target temperatures take longer to preheat to, and larger containers with more water also take longer to heat up (and vice versa with lower temperatures and less water).
A lot of immersion circulators heat water fairly quickly, faster than waiting for an oven to preheat.
It varies greatly (depending on the above mentioned factors, for example), but on average, it takes 15-30 minutes for sous vide cookers to preheat the water.
A pro tip, start with hot water from tap to speed up preheating time!
People choose to use sous vide cooking for a reason: the consistently precise results. They know that perfection takes time and accept that it’s worth the wait.
Also, waiting for water to preheat doesn’t take that long in the grand scheme of sous vide cooking.
If you want the absolute best, perfect results time and again, then I think it’s worth the wait to let the water bath preheat. A little added time doesn’t hurt.
Regardless of what you choose to do, remember that the cooking time should start when the water reaches the target temperature. This ensures your food is fully cooked.
If you don’t want to run the risk of prolonging preheating any further, here are my 3 favorite sous vide containers that come with an insulation sleeve and a lid: