The pH of blueberries typically falls within the range of 4.0 to 5.0. According to the pH scale, any substance with a pH below 7 is considered acidic, confirming that blueberries are indeed acidic. Ripe blueberries contain an acid content ranging from 1% to 2%, with citric acid being the primary organic acid at a concentration of 1.2%.
Citric acid constitutes a significant portion, accounting for 77% to 87% of the organic acids present in blueberry fruit. Additionally, quinic and malic acids contribute to 4% to 11% of the total acid content, while small quantities of succinic, tartaric, and shikimic acids are also detected.
As the blueberries ripen, their acid content decreases by approximately 22%, primarily attributed to a decline in citric acid. Research indicates a substantial 30% to 40% reduction in the citric acid level between ripe and overripe fruit, while the other acids undergo negligible changes. Since citric acid dominates the overall composition, although the minor acids experience a proportional increase, these changes merely result in a maximum 2.4% increment relative to the original proportion.
Citric acid content in blueberries
