Food

You can put stuff in a zip lock bag and suck out the air with a straw/force it out by dunking it in water. Aldi also have vacuum sealers at the moment I think.

Mostly benefits meat, but you can do veggies and stuff. I'd be keen to try eggs.

http://www.seriouseats.com/2013/10/sous-vide-101-all-about-eggs.html

http://www.seriouseats.com/sous-vide-101

Some of the high end vacuum sealers have zip locked bags with a valve built in. You seal the bag, attach a tube from the vacuum sealer and suck the air out.

They are more expensive and you need to buy their own brand bags though.

Anova were advertising this https://www.johnlewis.com/stasher-silicone-multi-purpose-kitchen-storage-bag-clear/p3244597 a reusable silicone bag.

You can use food bags but I found it was a bit of a hassle getting the air out so they'd float around and not always seal. I went with a cheapo vacuum sealer https://www.amazon.co.uk/dp/B075GVHJW4/ you can get a big roll where you seal both ends so you can fit them to the necessary size https://www.amazon.co.uk/Vacuum-Food-Sealer-Rolls-SousVideTools/dp/B00C9CS28O

Serious Eats has some good sous vide stuff http://www.seriouseats.com/2016/01/first-thing-to-cook-with-sous-vide-immersion-circulator-essential-recipes.html

Sous vide machines are pretty good at three things-

1. Cooking where you need a really precise temperature. Steaks and eggs are good examples. Also think tender chicken, caramelising chocolate, t-bone lamb, custard, fish fillets, parfaits, tender veg (asparagus), and pasteurisation.

2. Cooking things in marinades and/or their own juices. It retains flavour and keeps them moist.

3. Low and slow cooking- think stews, tough-cuts, curries and bourguignon. You don't actually need the bags for this (or indeed some of the temperature-specific stuff), just treat it as a large slow cooker, though be careful of things catching if the sides are thin.

Remember when you cook that there are two processes at work; you are breaking down the fibers of the food to make them tender. You are also killing the bacteria in the food to make them safe to eat. Some foods are low risk (clean veggies), some medium risk (steak - potential for harmful bacteria all the way through, but you're almost certainly ok if it's properly seared) and some are high risk (chicken and supermarket pork - you'd be daft to go below 65 C core temperature without the ability to measure & time it).

And if slow-cooking larger joints, it can be a good idea to bring it up to temperature in simmering stock. Bacteria multiplies rapidly between 4 & 50 degrees C, and big joints take a long time to come up to temp. This is a recipe for food poisoning, and having the stuff go rotten in the machine (really, it can happen).