Blueberries are so delicious and they make the perfect snack just about anytime, anywhere. Now days they are available year-round at quite reasonable prices. I couldn't begin to calculate how many pounds of Blueberries I have sold over the last 25 years... or Eaten!
When buying blueberries you should turn over the plastic container and check the bottom for wetness and mold. If there is a white liner in the bottom of the container make sure it has not turned blue, a sign that the fruit is not fresh. Always open the container and gently squeeze the berries, they should be firm and hard (not wrinkled). Soft berries spoil quickly and are usually a sign of old age or heat stroke.
Bigger fruit is ALWAYS sweeter. Blueberries have a natural white powdery look on their skin (as do plums and apples), this is a sign of freshness. Berries that look dull and lacklustre will be soft, mushy and almost tasteless.
Blueberries should be blue in color, immature berries will have a greenish or yellow tinge. If you are buying a case of berries make sure you gently shake the box of berries so you can check the interior bottom of the box for wetness and mold. You would be surprised how often a box of blueberries looks beautiful on top and the bottom is bad.
On extremely hot days, heat affects the quality of the fruit so reputatble growers will stop picking earlier in the day to maintain a certain quality standard. While not so reputable growers will continue picking fruit which becomes soft quickly due to the extreme temperatures. This can often reflected in the price at the store, a "No Name" brand versus a "Driscoll or Dole" label.
Generally speaking when you see a great buy for Blueberries, Strawberries, Cherries, Corn or Grapes in your local newspaper they are being sold as a loss leader to entice shoppers into their supermarkets.
Remember if you want good produce in your local grocery stores you need to write out customer complaint cards and include the grower's name whenever possible. With centralized purchasing the Produce Buyers often never see the produce being shipped to their stores. Customer complaints are taken seriously and will be checked out.