Hey Jason, what is the best way to seal my food for sous vide?
While a chambered vacuum sealer is the best way to do sous vide, they are several hundred dollars and overkill for many home kitchens. Many people turn to FoodSaver-type sealers, which can be convenient but they are expensive to buy bags for and can't really be used with liquids.
These freezer bags are great for sealing your food for sous vide and they work almost as well as a FoodSaver sealer if you know the trick to removing the air from them. It is called the "Water Displacement Method" or the Archimedes (ark-a-mead-ees) Principle. This trick simply uses the pressure from the water to force all the air out of the bag.
You can check out my comprehensive sous vide sealing guide for more information about other sealing methods for sous vide.
Getting all the air out of Ziploc bags is easy. You just place your food in the bag, including any liquids or marinades, and seal all but one corner of the bag. Place it in the water bath, being sure everything below the zip-line is covered by water. You can see how all the air is forced out of the pouch.
Then seal the rest of the bag. I try to seal the food before the water has heated up but if the water is hot you can use a wooden spoon to hold the bag under. I almost always use the gallon size Ziplocs, I find the extra room at the top makes them easier to seal.
There are several advantages to using Ziploc bags instead of a FoodSaver-type sealer. The biggest advantage is the ability to seal liquids. Ziploc bags work with both solids and liquids, so you can easily use marinades and sauces while you cook.
Another thing I really like about using Ziploc bags is that they are easy to open and re-seal. Many foods like sirloin, brisket, and pork shoulder have a lot of variation in the toughness of the meat and need different lengths of cooking time to fully tenderize them. The problem is that amount of time needed can be hard to determine before actually cooking them.
With Ziplocs I can open the pouch after the minimum amount of cooking time has passed and check the tenderness. If it needs more tenderizing I just re-seal the bag and put it back in the sous vide machine for a few more hours. When it's tender enough, I'll pull it out and it's ready to serve whenever I want. It really helps prevent under- and over-cooking foods.
Opening and re-sealing the bags is also helpful if the food has given off some gas and is starting to float. This often happens during longer cooks and it can be a pain to try and weigh down the bags.
With Ziplocs, you can release the gas, re-seal the bag, and the food will easily stay below the water again.
Of course, Ziploc Freezer Bags are also cheaper than FoodSaver bags. You can get 30 one-gallon bags on Amazon for under $5, about 15 cents a bag. In comparison, 28 one-gallon FoodSaver bags runs about $22, about 5 times as much.
I know a few people who have set aside the $15 difference every time they bought bags and in a year or two they could afford a new chambered vacuum sealer.
So now you know how to cheaply seal your food for sous vide. Thanks, and happy cooking!