In a
Cosmos article, the sourness of fruits are discussed and originates from the acidity of the vacuole. The vacuole is somewhat acidic due to the fact that
hydrogen ions are pumped into it. The more hydrogen ions that are pumped, the more acidity. Citrus fruit have varieties that express gees CitPH1 and CitPH5 which encode for transporter proteins that amplify the pumping of ions increasing the concentrations. These genes were had an reduced expression in sweet or low acidic like fruits. This can be beneficial to breeders for tastier fruits.
I love sour fruits so I was intrigued to read this article. I had learned that the purpose of a vacuole was for storage of different of nutrients, toxins, and aids in hydrostatic pressure. However, I was informed through this article that the sourness is derived from the amount of hydrogen ions are being pumped into it the organelle.
