Tinned food often contains inulin which neither we, nor our pets, can digest but the bacteria in our colons can, do and produce the stench. It is the same as the Jerusalem artichokes do - because they store inulin.
Inulin is a carbohydrate so it is calorie rich and the bacteria love it - as they do baked bean starch.
If you look on the nutrient list it is usually mentioned - if not then add up the % carbohydrates and any unnamed is probably the inulin. We do need to keep our friendly bacteria healthy so it is useful!
The Republic of Ireland and their tensions with migrants.