Beers are broadly divided into two categories: top-fermented ales and bottom-fermented lagers. Stouts are a type of ale that uses slow-fermenting yeast that evolved out of the porter style. Stouts tend to be thicker, darker, opaque beers with higher specific gravity - similar to milk. They are usually less bitter than other ales, and typically exhibit tones like chocolate, coffee, oatmeal, and milk.
Foods that are sharp can scratch the tissue, leading to discomfort. Spicy foods or foods that are extremely hot or cold can also cause the roof of the mouth to become damaged, leading to swelling or pain. Tobacco use can also damage the tissue, leading to discomfort on the palate.
Bitter taste in mouth is a common side effect of many medications. It could be due to infection of gums or cavities in teeth. It could also be an abnormal perception of bitter taste called dysgeusia. GERD and heart burn too cause metallic taste in mouth. Post nasal drip as in sinusitis, salivary glands infection, pharyngitis or strep infection too are common causes.