In winter when human body doesn't have enough vitamins, it is worth paying special attention to bananas. This is a record-holder fruit by amount of vitamins and microcells which you can get even in winter. There are a lot of potassium, calcium, magnesium, phosphorus, iron and also important amino acids in banana. Good banana has juicy yellow color and smooth brilliant surface. Black points on a peel surface – a sign of that the fruit will be sweet, but it is impossible to store such banana any more.