求翻译：水果中的酸主要是有机酸，中和以后样品 pH 值偏碱性。一般方法是采用 NaoH 标 准溶液滴定样品溶液，以酚酞为指示剂当溶液由无色变为粉红色时为终点。是什么意思？

In the fruit acid is mainly organic acid, and high value after pH samples alkaline. The general approach is used by titration NaoH standard solution samples to phenolphthalein solution for indicator when solution to the terminus at the colorless to pink.

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Fruit acids are mainly organic acids, alkaline pH value after neutralizing samples. General method used is the sample titration solution of NaoH standard solution, using phenolphthalein as an indicator for when the solution from colorless to Pink is the ending point.