Immature and marketable highbush blueberries often are separated by buoyancy in water tanks. Calcium chloride was added to the water to improve berry firmness or integrity. Berries were immersed in 0% to 4% CaCl2 and held at 2C for several days. Vertical compression of a column of berries decreased linearly with increased CaCl2 concentration, a result indicating that CaCl2 increased the ability of the berries to resist physical damage. Immersion duration (0.5, 2, or 4 minutes) did not affect results. However, rinsing berries in water immediately after immersing them in CaCl2 negated the effect. Taste panelists associated an objectionable, salty taste with berries immersed in 2% and 4% CaCl2, but not for those immersed in 1% CaCl2.

No abstract

Deformed or damaged berries reduce the grade of frozen highbush blueberries (Vaccinium corymbosum L.). Before berries are frozen, immature fruit are commonly removed by density sorting in water tanks. Three studies were conducted to determine if the firmness or quality of highbush blueberries could be improved by the addition of CaCl2 to sorting tank water. `Bluecrop' and `Jersey' berries were dipped in CaCl2 solutions (0.0-4.0%) for periods of 0.5-8.0 minutes. The effect of rinsing the fruit after treatment was also studied. Berries were held at 2C for several days before evaluation. A 61.5 cm length of PVC pipe (4.0 cm. I.D.) was filled to a depth of 50 cm. with berries and dropped 4 times on to a hard surface from a height of 10 cm. The compression of the column of berries was measured and berries were removed and visually sorted according to the degree of damage. The amount of compression and number of damaged berries were inversely related to the CaCl2 concentration. Rinsing berries immediately after dips negated the effects of CaCl2. Treatment with CaCl2 may result in objectionable flavors.