pH was a determinant factor in the resulting chemical composition of citron fruit bars as shown by a study where this preserve was prepared at pH 3.4, 3.7, 4.1, and 4.3. Vitamin C destruction increased with decreasing pH, except in the case of fruit bars at 4.1 and 4.3, where a reverse tendency seemed to appear. Total acidity in the product was directly related to the pH. Reducing and non-reducing sugars agreed with results reported in the literature related to the inversion of sucrose. In preparing citron fruit bars with sucrose, a pH of 4.1 is recommended.