Hydrolysis of sucrose

Sucrose is soluble in water but its molecules are too big to pass through the cell membrane during diffusion. It can only be broken down through a hydrolysis reaction.

(P.S. Although both glucose and fructose are reducing sugars, sucrose is not because it does not contain anomeric hydroxyl groups, and does not reduce the chemicals present in its structure through oxidation.)

Hydrolysis is so slow that solutions of sucrose can sit for years with negligible change. We may add enzyme (sucrase) and weak acids (e.g. cream of tartar or lemon juice *both weak acids) to speed up the reaction.

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水解是一種化工單元過程，是利用水將物質分解形成新的物質的過程。通常是指鹽類的水解平衡。無機物在水中分解通常是雙分解過程，屬於複分解反應。水分子也被分解成氫離子和氫氧根，和被水解的物質殘片結合形成新物質，如：氯氣在水中分解，一個氯離子和一個水被分解的氫離子結合成鹽酸，水分子的另一個氫氧根離子與另一個氯離子結合成次氯酸 Cl2 → Cl+ + Cl-
H2O → H+ + OH-
Cl- + H+ → HCl(aq)
Cl+ + OH- → HClO(aq)
碳酸鈉水解會產生碳酸氫鈉和氫氧化鈉 Na2CO3 → 2Na+ + CO32-
H2O → H+ + OH-
Na+ + OH- → NaOH(aq)
Na+ + H2O + CO32- → NaHCO3(aq)
氯化銨水解會產生鹽酸和氨水 NH4Cl → NH4+ + Cl-
H2O → H+ + OH-
NH4+ + OH- → NH3·H2O(aq)
Cl- + H+ → HCl(aq)

有機物的分子一般都比較大，水解時需要酸或鹼作為催化劑，有時也用生物活性酶作為催化劑。在酸性水溶液中脂肪會水解成甘油和脂肪酸；澱粉會水解成麥芽糖、葡萄糖等；蛋白質會水解成胺基酸等分子量比較小的物質。在鹼性水溶液中，脂肪會分解成甘油和固體脂肪酸鹽，即肥皂，因此這種水解也叫作皂化反應。



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蔗糖是人類基本的食品添加劑之一，已有幾千年的歷史。以蔗糖為主要成分的食糖根據純度的由高到低又分為：冰糖（99.9%）、白砂糖（99.5%）、綿白糖（97.9%）和赤砂糖（也稱紅糖或黑糖）（89%）。


The hydrolysis of sucrose to glucose and fructose is exergonic?


The hydrolysis of sucrose to glucose and fructose is exergonic?The hydrolysis of sucrose to glucose and fructose...change in free energy of the reaction ...
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why does hydrolysis starch take longer than hydrolysis of sucrose?