Sous vide is a popular cooking technique that you’ll often hear talked about in cooking shows, or mentioned on message boards about restaurants or food. Reddit even has a whole subreddit dedicated to the topic of sous vide food.
While discussions are heating up, sous vide is not a new culinary topic at all. Sous vide as we know it was made popular by professional chefs in the 1970s who introduced it to their restaurants as a way to serve great dishes, hot to the customer.
Today, the sous vide (or literally “under vacuum) cooking technique is used in more than just gourmet or professional kitchens. Excellent sous vide results can also be achieved at home with the purchase of a cooker.
If you’re new to sous vide food and why it’s so popular right now, you might have a lot of questions. Yes, there’s a right and wrong way to do sous vide. Yes, sous vide is much like a slow cooker, but not exactly the same thing. No, sous vide isn’t just boiling food in a bag.
What about leaving sous vide unattended? Can you leave sous vide on at night?
Here’s what you should know about sous vide cookers and what you should do with them during the day or night when they might be left to run.
What is Sous Vide Really?
The term “sous vide” refers to food that has been prepared and then vacuum sealed, made to be brought up to a higher temperature later – usually right before serving. Slow cookers and broilers existed some time before sous vide, but for these early cooking methods, vacuum sealing was not used.
For the record, you can’t just boil your food in a bag and refer to it as sous vide. Cheaper restaurants might, but that’s not how it works in the culinary business – or at home.
Vacuum sealing food helps the flavors to penetrate, but also ensures that your food cooks safely.
The earliest forms of sous vide had to convert industrial equipment that wasn’t meant for cooking. Today, it’s easy to go online and buy a sous vide cooker that provides you with industrial power right in your own kitchen.
How Long Can You Leave Sous Vide On For?
Proper, safe sous vide is all about proper vacuum sealing that removes all the air (and at least some of the potential for bacterial growth inside the bag). Safe sous vide also has a lot to do with the temperature at which the food is brought up to, and how long the food is kept at this temperature for.
Sous vide can be left for 24 to 48 hours, providing that the food maintains a temperature of at least 130 to 150ºF. Serve immediately after, or let cool down and immediately freeze. For food safety reasons, this process can only be followed once!
Can You Leave Sous Vide Overnight?
Yes, though this depends on the specifications you’ve set for your sous vide cooker and what you intend to cook. Anything that requires time to soften, tenderize or infuse will be fine overnight – though any food types that will soften, can get too soft or practically disappear when subjected to high temperatures overnight.
If you intend to leave your sous vide cooker overnight, set a lower temperature rather than a higher one, and have at least some experience with what you’re hoping to cook.
Can You Leave a Sous Vide Cooker on All Day?
Yes, although the exact same answer will apply to daytime sous vide meals.
A constant, high temperature is important for food safety. It also depends on what you are hoping to get out of the end-result. Stews, bolognese and any food type that needs a “slow” cooking process will be fine – though more delicate ingredients will simply turn into cooked pulp.
Is a Sous Vide Cooker Safe to Leave Alone?
Yes, and in this way a sous vide cooker works a lot like a slow cooker.
Modern sous vide cookers have been made for convenience, and it’s fine to leave a sous vide cooker unattended for a few hours – as long as there are no animals, children or electrical faults present. Always place your sous vide cooker away from any environmental hazards, especially if you are not there to watch it.
Some types of sous vide cookers can be set to switch on (or off) at or after a specific time. Many busy people prefer to time their sous vide cooker so that they have a perfect meal when they get back.
What Foods Will Overcook Overnight in a Sous Vide?
Any solid foods can only become more tender in a sous vide cooker when they’re given time, and stews or soups just become more rich and concentrated. But when foods are more delicate, you can expect them to either overcook or disappear in your sous vide cooker.
If food goes in soft, it will come out as softer when left for a longer period of time. Eventually most chefs and home cooks develop a natural feel for when this is.
One great example, is ribs.
Can a Sous Vide Cooker Overheat?
A sous vide cooker should never overheat when it’s functioning properly.
An overheating or malfunctioning sous vide cooker is a bad sign, and means that it’s going to need immediate replacement.
Can You Time a Sous Vide Cooker?
According to Anova’s instructions, yes – and all you have to do is use the Timer button, and then use the + and – settings to refine your cooking time. Not all sous vide cookers work like this, but most of them these days include a timer setting for easier use.
So in short, this will depend on your Sous Vide Machine.
Can You Freeze Sous Vide Food?
Yes, sous vide food can be frozen – but only once after it has been prepared.
Food that has been defrosted once should not be re-frozen, or bought back up to temperature. Any foods that are repetitively reheated and cooled can cause what’s called “take-away syndrome”, a sometimes fatal condition tied to exposed foods.