本研究利用高效能液相層析儀,測定桶柑果實發育期間果汁中可溶性醣類及有機酸含量變化。主要的可溶性醣類以蔗糖、果糖和葡萄糖三種為分析對象,蔗糖在醣類成分中最佔優勢,隨著果實成長而顯著增加,由每100 ml果汁中含有1.04克增加至6.62克。果糖及葡萄糖的含量較少,且在各個時期二者幾近相等,成熟時,二者含量遠不如蔗糖。測出的有機酸有:葡萄糖醛酸、草酸、酒石酸、蘋果酸、異枸櫞酸、抗壞血酸、乳酸、醋酸、草醋酸、α-酮戊二酸、枸櫞酸、烏頭酸和胡索酸等酸,在整個果實生長過程中,以枸櫞酸的變化最顯著,次為蘋果酸,而其它的有機酸變化較不明顯。由枸櫞酸與蘋果酸的比率在十二月降至低平緩狀態,得知成熟期的到達,但延後採收,則有較高糖度。
Changes of soluble sugar and organic acid components of tankan fruits juice were investigated by means of high performance liquid chromatography (HPLC). The predominant sugars detected in the fruit juice were sucrose, fructose and glucose. Sucrose concentration increased from 1.04 gm to 6.62 gm per 100 ml juice during fruit growth and maturation. The concentrations of fructose and glucose were less than that of sucrose and didn't vary significantly during fruit growth and maturation.The organic acids detected in tankan fruits were oxalic, tartaric, malic, isocitric, ascorbic, lactic, acetic, oxaloacetic, α-ketoglutaric, citric, aconitic and fumaric acid. Citric acid and malic acid were the organic acids showed pronounced changes during fruit growth and maturation, while other acids were present only in minute amounts throughout maturation.Fruits were mature when the citrate/malate ratio reached low levels in December even sugar contents were still increasing.