Sous vide bags

[Kent Wang]

What kind of bags are required for sous vide? We know that the FoodSaver and Ziploc brand are fine. I'm not sure what kind of bags commercial kitchens use. Is it a special kind?

I buy a lot of meat from the farmers market, which comes frozen and vacuum-bagged from a meat processing facility. The bag appears to be the same kind as the professional sous vide bags that I've seen. Can I just put this directly in my waterbath without changing bags?

I just tried some pork chops at 131F for 4 hours and they turned out fine, as far as I could tell, though it's possible that it leeched out some tasteless chemicals.

Sometimes, with bony cuts, there is a thicker plastic sheet (similar in texture to the FoodSaver bags but thicker) placed over the bony protrusions so that they don't puncture the bag. Is that heat stable too?

[bmdaniel]

I occasionally use the croyvac bags from the purveyor with no ill effects to date. I'd be interested to hear whether these bags are just the same safe PE bags that I use when I bag myself.

[Okanagancook]

Thomas Keller, in "Under Pressure" says he uses an all purpose 0.003 inch thick bag that is rated for use with food products and safe at boiling temperatures, 212 degrees F. I checked various websites to try and find the thickness of Food Saver Bags but could not find a reference to the thickness.

[Kent Wang]

I venture that there might be some materials that can handle lower sous vide temperatures (let's say under 140F) but not boiling.

[bmdaniel]

If you are looking for a specific recommendation, I prefer these: http://www.qualitymatters.com/Weston-Vacuum-Sealer-Bags-Variety-Pack-50-bag-p/qm300107w.htm to the foodsaver bags. You can buy them as pre-made bags (which is easier but less flexible) or rolls.

[qrn]

just measured the FS bags, smooth side is .0025, side with grooves is .007 (inch)

Bud