The burning sensation often seasoned with snus is due to the nicotine itself (much like the tingle of nicotine gum) and many food additives which include sodium carbonate (E500). Sodium carbonate is actually a meals additive utilized to improve the pH in the tobacco (reduce the acidity). From the U.S., https://images.google.es/url?q=https%3A%2F%2Ficyshop.es%2F%3Fcollections%2Fsnus