Sous vide cooking is the latest trend for the serious home cook. This method combines a very long cooking time with a hot water bath to create perfectly cooked steaks, without the risk of overcooking.
But how appetizing does it sound to soak your meat in water for hours on end? If the answer is not very, that’s because you are missing an important step. Before you stick them inside a sous vide machine, you need to vacuum-seal the bag in which you will put your seasoned meat.
If you already have a vacuum sealer, then this may not be a big deal at all: most of these machines can create an accurate and precise vacuum seal in less than two minutes. If you don’t – then the cost of a sous vide machine with that of a vacuum sealer may put you off from this innovative method altogether.
Fortunately, We The Internet are here to the rescue. Today, we will go through a way to vacuum seal your beef for sous vide without using any extra appliances. You just need to get regular Ziplock bags for sous vide!
Don’t Have a Sealing machine? How to Use Ziploc Bags Instead
The method we will explore today is known as either the water displacement method or the slow immersion method. This tactic uses natural water pressure to get rid of all pockets of air before you seal the bag.
First, let’s go over the materials you will need:
- A premium cut of steak – the kind you don’t want to risk overcooking
- A pot of water, large enough to fit the steak and more
- Ziplock bags
Here, we will be using the term “Ziplock bag” out of pure convenience, as this is simply the most popular brand. The bags don’t need to be of that specific brand. Any kind of plastic, once the bags are BPA free and resealable, will do.
Place food in Ziplock plastic bag
Season your steaks or chicken thoroughly, and place them inside the bag. Ignore the air, but try to push the piece of beef towards the bottom as much as you can
Close most of the bag
Starting from the corner, slide the “zipper” meant to close the bag tightly. Don’t close it completely yet – it is still full of air, which can potentially ruin your sous vide steak (we will explain why later).
Instead, leave a small corner of the bag open, no larger than half an inch.
Fill the water container
Important: this is not the water in which you will be cooking. Therefore, this water should be cold or at room temperature.
Fill the container enough to submerge the entire bag, but leave some space before the edge to avoid any spilling.
Slowly submerge the bag
Hold the bag from the open corner, and slowly submerge the bag and steak within the water container. You will see that the pressure caused by the water from all sides, will slowly push the air out of the bag.
You can check this is happening properly because your plastic bag will adhere itself tightly around the meat.
Close it back
Be very careful when you reach the open corner of the bag, as you don’t want any water to come inside the bag.
Right before that corner begins to touch the water, start closing it and seal the bag
You are ready for cooking
But it will be a few hours until you can eat! This is because sous vide cooking relies in long cooking times to yield precision. Once your bag is sealed, you can set up your sous vide machine and start thinking about your side dishes.
Why Do You Need Vacuum Sealed Bags For Sous Vide?
Sure, it makes sense to keep the water away from our expensive tenderloin or strip steak – after all, you don’t want to boil it!
But why do you need the bag to be completely air-free and vacuum sealed? The answer lies in physics and chemistry.
As we have mentioned before, sous vide cooking was created to prevent overcooking the meat, but still cooking it thoroughly. When you simply use a hot skillet, it can take as little as 30 seconds to denature the protein fibers in your steak and denature it.
Instead, sous vide uses water well below boiling point (usually around 60°C or 140° F). The idea is that the water, as it never goes above that temperature, will prevent the meat from reaching any high temperatures: the surrounding water will disperse any extra heat.
However, the air will heat much faster than water. If you don’t use any vacuum-sealed bags for sous vide, the little pockets of air inside the bag can reach boiling temperature or even above. This will cause a piece (or even a whole side) of your steak to overcook, and you will end up with chewy, stringy meat.
If you want to experiment with sous vide method don’t need an expensive vacuum sealer to take the air out of the bag. Invest in a good sous vide machine and use the water displacement method instead. With it, you can do a pretty thorough vacuum seal with tools you already have in your kitchen.
If you want to learn more about how to get perfectly-cooked steaks with a sous vide machine, check out this guide. Bon appetit!