I just got the following reply from Ziploc:
"Hi Roman – thank you for your interest in Ziploc® brand Bags.
It means a lot to us that you use Ziploc®; unfortunately, our bags are not designed nor tested for Sous Vide, nor any type of water bath cooking. Even with their 110° C/230° F° softening point, we cannot recommend them for such use. We formulate and test every product for specific household tasks, and can only recommend using them according to their label directions.
If you’d like to know more about Ziploc® brand Freezer and Storage Bags and their make-up, please check our ingredient website:
If you have any additional concerns about the safety of our bags, feel free to call our product safety specialists at 866-231-5406. They will be happy to assist further and are available 24 hours a day.
Kind regards,
Denise
Consumer Relationship Center
SC Johnson, A Family Company
USA 1-800-558-5252 | scjohnson.com
Canada 1-800-558-5566 | scjohnson.ca"