I firmly believe in the benefits of blueberries but I don't understand the concentrate approach.   Blueberries are widely available and relatively cheap with 600 gram frozen packs going for $5 or $6.  This amount would easily last an individual a week.   Blueberries are by far the best and cheapest superfood.  

Why buy blueberries in anything other than their whole food, natural form??  Extracts are processed and more expensive.   Buy frozen or from Chile over most of the year and then go to pick your own farms for 6 weeks in the summer for la creme de la creme.

Cheers,
John Meyer