Some people say you need to pre-sear your food before you cook them sous vide. Other people say to sear afterwards. Some say to do both. What's the right answer?
This is a great question and one that many people run into. I'll look at both sides of the question, whether to pre-sear and whether to post-sear. I'll start with the post-sear as it's the easiest to answer.
If you want good flavor and crust on your food, you will always want to sear it when it is done cooking. Even if you do a pre-sear, the crust itself will go away and can only be established by searing it after the sous vide process is over.
Not all food needs a post-sear, such as some fish or chicken and beef that is going into a sauce and you don't want or need the extra flavor for. But the majority of food benefits greatly from a post sear.
Note: You can read more about searing in my How to Sear Sous Vide Foods article.
It's common knowledge that sous vide foods need a sear after cooking to crisp up the exterior and add the wonderful Maillard reaction. However, whether or not to sear before sous vide is one of the more controversial questions around sous vide.
A lot of it comes down to what you are trying to accomplish.
An undisputed benefit of pre-searing food is to sanitize the outside of the meat. A quick sear will kill any bacteria present on the surface. This searing is much more useful for items with longer cooking times where there may be time for bacterial growth.
Though another probably more effective way to do this is to dip the meat into boiling water for a few seconds before bagging the food.
Pre-searing also helps the food brown more quickly during the post-sear, though the post-searing time usually isn't too large to begin with. It can help with finicky foods that have a habit of overcooking during the sear, such as thinner steaks.
Some people feel that doing a pre-sear of the meat will also help flavor it and allow the seared flavors to penetrate the meat during the cooking time. Other people feel that the pre-sear flavors do not penetrate the meat or add any additional flavors, making the additional step irrelevant to the final outcome.
There is no consensus on this issue, Modernist Cuisine and Serious Eats both say not to pre-sear while Chef Steps and The French Culinary Institute both recommend it. However, with the large amount of people looking into the issue and experimenting with it, I think it's pretty clear that the flavor benefits, if there are any, are very minimal.
If you work in a Michelin starred restaurant where this minor flavor change is important, then running your own blind taste tests makes a lot of sense. For the rest of us cooks, doing a pre-sear probably won't make a noticeable difference, so feel free to skip the step, unless you are trying to pasteurize the surface. And if you feel strongly that the pre-sear makes a flavor difference and don't mind the extra step, by all means, give it a pre-sear!
Hopefully you understand the reasons to sear pre- and post-sous vide!
If you like this you can get more than 85 other inspiring recipes to get you on your way to sous vide success. It's all in my best selling book Modernist Cooking Made Easy: Sous Vide - Get Your Copy Today!