We don’t have a good answer for this because Bertolli does not give a definitive answer themselves.
Copied from their website: Ingredients that may contain gluten are always listed on the label. Since product formulations change from time to time, we do not have a printed list of products that identifies those products that contain specific allergens or gluten. The best advice we can give you is to check the ingredient list on the label. If you cannot determine whether the product contains the ingredient in question, we suggest you do not use it.