Молекулярная гастрономия для креативных шеф-поваров (англ. язык) - страница 13

Молекулярная гастрономия для креативных шеф-поваров (англ. язык)

whereas glucose is slightly less soluble and therefore produces a less thick solution when dissolved in

water. Sucrose is also surprisingly soluble in water – it is actually the second most soluble sugar in

water and can dissolve in half its volume of water to produce a thick solution.

After a certain point, no more sugar can dissolve in a sugar solution because there will be no more

water molecules available to bond with the added sugar –the sugar will stay in crystal form and will not

dissolve. We say that the sugar solution is saturated.

Effect of heat

Standard heating

Unlike the carbohydrates, proteins and fats, the sugars are small and stable molecules that are

remarkably resistant to heat. A mixture of a sugar and water can be heated to boiling temperatures

without affecting the sugar structure. As the mixture is boiled, water molecules evaporate from the

mixture, and gradually the solution will become more and more concentrated in sugar, the sugar

molecules will start to bond with themselves to form pure masses or solid crystals. This is how sweets

are made.

The boiling temperature of a sugar solution will always be higher than 100°C. This is because heat is

needed to not only break the water-water linkages but also to break the strong sugar-water linkages.

So the solution will need to be heated to a slightly higher temperature before the water can become a

gas.

Also, the more concentrated the solution is in sugar,...

a slightly higher temperature before the water can become a

gas.

Also, the more concentrated the solution is in sugar, the higher the boiling point. Therefore, as the

solution is heated, more and more water evaporates, so the solution become more and more

concentrated in sugar, further increasing in boiling point. A sugar solution with a sugar concentration of

90% will boil at about 125°C.

Extreme heat –caramelisation

If simple sugars are heated to a sufficiently high temperature (which will happen when al the water has

evaporated from a sugar solution), it will eventually start to develop a characteristic “caramel” taste as

the sugar molecules themselves start to break down. The monosaccharides are fairly reactive, and

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