Why is strawberry sweet and lemon sour?

When evaluating the sugar levels between a strawberry and a lemon, one would automatically assume that a strawberry contains more sugar due to its sweet taste compared to that of a lemon. But on the contrary, the study shows that lemon contains 70 percent sugar and a strawberry contains only 40 percent of sugar. The tanginess of lemon is due to its high amount of citric acid. Although the percentage of the citric acid is a minuscule 3 to 6 percent as compared to strawberries; it still manages to dominate the saccharine levels in lemons, resulting in the sour taste.

A lemon's tanginess is attributed to the high concentration of citric acid. While the citric acid percentage is a minuscule 3 to 6 percent relative to strawberries, it nevertheless tends to dominate the levels of saccharin in lemons, resulting in a bitter taste.