It is not recommended to can products without adequate liquid because the heat penetration would not be the same so the internal temperature of the jar would be different so there is no guarantee that the processing time would be safe.  If it was within 24 hours I would recommend opening the jars and add  brine (1 1/2 Tablespoons salt per quart of water).  This is the same salt concentration that would be in your kraut.  You could then reprocess your jars. Your kraut will also probably be quite dry without liquid.    

If you have other food preservation questions you might like to call the OSU Food Preservation/safety Hotline, open M-F 9 am-4 pm until Mid October.  Certified Master Food Preservers are available to answer your questions.  The number is <personal data hidden>. 

Thanks for using Ask an Expert 

Nellie Oehler