11-29-2013, 10:36 AM
Why Does Oil Fry And Why Does Water Boil?
Such a trivial question is often underlooked normally, but have you wondered why putting a potato on hot oil fries it, while putting it on hot water boils it?
This happens for two main factors: oil's boiling temperature and Maillard's Reaction.
The oil is stable even if you heat it at temperatures higher than 100º C. This means that less oil is evaporated, and thus the superficial contact between the oil and the potato is much higher than the moving, boiling water. The potato's moisture evaporates instantly in contact with hot oil, which causes the bubbling.
Finally, the Maillard's Reaction is a special reaction in which the starch of the potato combines with the carbon present in the hot oil's molecules, giving it the distinct golden coloration and the tasty flavor. In addition, this forms a crust around the potato, protecting from further water evaporation from the potato: what you get is a crusty exterior and a moist interior for your french fries. The Maillard's Reaction also happens when you roast meat. This is why you flour the chicken first to deep fry it: it maximizes the reaction, giving you crisp and tasty chicken wings.
Such a trivial question is often underlooked normally, but have you wondered why putting a potato on hot oil fries it, while putting it on hot water boils it?
This happens for two main factors: oil's boiling temperature and Maillard's Reaction.
The oil is stable even if you heat it at temperatures higher than 100º C. This means that less oil is evaporated, and thus the superficial contact between the oil and the potato is much higher than the moving, boiling water. The potato's moisture evaporates instantly in contact with hot oil, which causes the bubbling.
Finally, the Maillard's Reaction is a special reaction in which the starch of the potato combines with the carbon present in the hot oil's molecules, giving it the distinct golden coloration and the tasty flavor. In addition, this forms a crust around the potato, protecting from further water evaporation from the potato: what you get is a crusty exterior and a moist interior for your french fries. The Maillard's Reaction also happens when you roast meat. This is why you flour the chicken first to deep fry it: it maximizes the reaction, giving you crisp and tasty chicken wings.