Blueberries are the fruit of the flowering blueberry plant. The berry is dark purple when ripe and has a sweet taste which can vary with acidity. These popular berries are sold as either frozen or fresh and are used for a wide range of products including jelly, jams, blueberry pies, muffins, snack foods and cereals. The raw berries, fresh or frozen, are highly recommended as they have the most flavour and provide the most nutritional benefits.