more on sausage casings

Question

Dear Rav, I found this on the OK site. Kedassia are the right wing kashrut agency in England. There is a product manufactured from skins of animals and used as casing for sausages such as salami, frankfurters, liverwurst and balonies. This is produced in a way that is similar to gelatin. In America there is a factory that makes these casings from Kosher slaughtered animals. In Germany there is a plant that makes the same casings from the skins of non-Kosher animals and it has Kosher supervision from a rabbi in Munich. There are Kosher delicatessen manufacturers in America and Europe who use the above-mentioned casings made from non-kosher animals with a Hechsher. The reason for this is because some rabbis consider this product chemically changed and therefore permissible according to Halacha. Of course, there are many different opinions concerning this. The question is whether it is really chemically changed an also whether the Halacha permits the use of these skins even if they are chemically changed. I was amazed to discover that Kedasiah in London permits the use of the casings made from these non-kosher skins from Germany Martin