# How can I know when a thick simple syrup is done cooking?

When making a thick simple syrup (1 part water, 1 part white sugar), how can I know when I've cooked the sugar for long enough? Is it possible to overcook this?

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I'm pretty sure you're referring to simple syrup, so I've edited and retagged accordingly - let me know if I've made a mistake. – Aaronut Feb 25 '11 at 19:10

## 3 Answers

You aren't actually trying to cook anything. When you heat a solution, it makes dissolving a solid in to that solution much easier. So you can dissolve more sugar in to hot water than cold water. With a 1:1 ratio, you wouldn't be able to get all the sugar in to solution with cold water. So, you heat the water to allow more sugar to become part of the solution. So the answer is, as soon as there is no visible sugar in the water, you are done.

If you were to cook it for longer, you would reduce the syrup, increasing the concentration of sugar in the solution. You'd have to reduce it an awful lot before you burnt this. However, if you reduce it too much, then the liquid will become solid when it is cooled. Both of those would probably qualify as "over cooked".

Here's a nice science description of sugar solubility. Interestingly, they say that sugar has such high solubility in water that you can get 1800g in to 1L. Using this volume to weight conversion site, that's approximately 7.5 cups of sugar in 1L of water. 1L = 4.2 cups, so you can get ~1.8 Cups of sugar in to 1 cup of water (under ideal circumstances). So, if you are actually interested in cooking your water off to get a more sugary syrup, you can't reduce the water to less than 1 / 1.8 = or 55% of the original volume. However, if you do want a ratio higher that 1:1, then I would suggest introducing the appropriate amount of sugar in the first place and stopping when the sugar is dissolved rather than using less sugar and cooking the liquid down, as the first approach is much more precise.

(for purposes of this answer, I have ignored the possibility of super saturating the syrup, as that would be essentially useless for cooking....although it would be funny)

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It's steeping. You can boil 1 cup water (remove from heat source) add 1 cup of sugar, stir until sugar is dissolved and you have simple syrup. Clover.

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This is incorrect. For most applications, you need a very specific consistency, and it is reached after boiling until a certain proportion is reached (which can be recognized by measuring the temperature, or by doing a water test). If you do it the way you recommend, you get something which is not usable for most recipes out there. – rumtscho Sep 24 '15 at 10:38

The answer provided by Yossarian is largely accurate, but it should be emended to point out that cooking is in fact taking place.

Yes, the increased molecular activity resulting from the heat does facilitate the dissolution of the sugar molecules (this is why your sugar doesn't dissolve in your iced tea but does in your hot tea). But most simple syrups are cooked for at lease some time beyond the point where the sugar is simply dissolved. This is especially true of flavored simples where you'd have to steep any herbs or the like for a lot longer than it takes to get the sugar dissolved (I make ginger and mint syrups often, and the ginger in particular requires a good amount of time in the solution before I strain it out).

The other thing to note is that if you continue to cook it for a lengthy period of time, it will become caramel. No, this will not get you traditional caramel, as that requires butter and cream, but it will still darken and go through the soft ball, hard ball, and hard crack stages as it cooks.

Once solution is a candy thermometer, but you really only need that precision if you're trying to get the mixture to one of the above-mentioned stages. A better solution to test your syrup is as follows:

Place a bowl or plate in the freezer while you cook the syrup. When the syrup gets to the point you think you're looking for, remove it from the heat, take the cold dish out of the freezer, spoon a bit of the syrup onto the plate and return it to the freezer for a couple minutes. It will cool rapidly enough that when you pull it back out it will give you a good indication of what your final product will be like. If it's too thin, return the pot to the heat. Too thick? You have to start over.

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Do you have any sources for this because I disagree. All syrups are just changes in concentration. Simply staying on the heat to steep is not cooking; The sugar isn't changing. As you said, you have to boil it all the way until most of the water is gone before things start to caramelize and darken. This is way past what anyone would call a simple syrup. – Sobachatina Aug 14 '15 at 15:14
If we're talking about the definition of cooking, I'd argue that it has, to some degree, a subjective meaning so I won't bother with the dictionary.com definition that basically says "to prepare food by applying heat." I'd further argue that if you're keeping something on the heat, you're not "steeping" it. You're cooking it. Steeping takes place off of a heat source (again - tea, French press coffee, etc.). As far as sources, a lot of this is information I've gathered over the years, but I found some good info here: yale.edu/ynhti/curriculum/units/2009/3/09.03.05.x.html. – JShweky Aug 14 '15 at 15:23
Fair enough. I agree it's a semantic argument. Simple syrup recipes almost always call for just dissolving the sugar, as Yossarian pointed out. Whether you call that "cooking" or not is subjective. – Sobachatina Aug 14 '15 at 16:11