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Can someone help me find values for the densities of simple syrups? Specificually I am looking for values of 66.6 Brix solution (2:1 mass ratio syrup) and 50 Brix solution (1:1 syrup).

I would also very much apprechiate it if you provided values for other brix solutions as well. Maybe there is a graph showing density as a fuction of brix for simple syrups?


One reason why I want to know is so that I can calculate the amount of water and sugar I need to get a certain volume of simple syrup. Here is how: if I have m grams of sugar, w grams of water, the density is D and the volume is V then V×D=m+w. For a 2:1 ratio, we have m=2w (2 times as much sugar as water), so we get: V×D=2w+w=3w. So, to calculate the amount of water we need in the solution, we do: (V×D)/3=w which gives us the amount of water needed. To find the sugar we multiply by 2. Since the density of water is 1g/mL, we can just measure w mL. (In this calculation I have assumed that the mass before and after making the syrup is the same. Although some water may be lost due to boiling, I think this is a reasonable assumption).


Edit: I made 5dL (500mL) of 2:1 (66 brix) solution. Here is how I calculated how much water and sugar I needed: Water: (500mL×1.33g/mL)/3≈222g. Since water has a density of 1g/mL, this is equivalent to 222mL or 2.22dL of water. Sugar: Since the solution is 2:1, we just double the amount of water: 2×221.6666...g=443.333...g≈443g. So, if we mix 443g sugar and 2.22dL of water, we get a simple syrup solution with a (222+443)g/500mL=1.33g/mL density, which has a brix of 66.

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  • By "density", do you mean "specific gravity" or something else?
    – FuzzyChef
    Commented Mar 1 at 21:55
  • I mean the weight devided by the volume. But specific gravity is just a ratio of densities, so I can work with that too (often compared to water, which has a density of apporximatley 1kg/L or 1g/mL).
    – Vebjorn
    Commented Mar 1 at 22:03
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    Well, SG is just density expressed in kg/L. Was just checking that you didn't mean "viscosity" or something else.
    – FuzzyChef
    Commented Mar 1 at 22:25
  • I'm pretty sure SG is unitless though? Because you take the density and devide by the density of water. If you use kg/L, then the density of water is 1 kg/L and the SG numerical value is equal to the density value. You can, however, use other units and you would still get the same numerical value for SG. britannica.com/science/specific-gravity
    – Vebjorn
    Commented Mar 1 at 22:35
  • Theoretically, yes, but in practice everyone's comparing against ideal water.
    – FuzzyChef
    Commented Mar 1 at 22:40

3 Answers 3

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The Engineering Toolbox also has tables and graphs for these sorts of things. They have a number of charts depending on which measure of concentration you use, but the weight percentage one in an aqueous solution at 20 C/68 F looks like this:

weight percentage plot image source: The Engineering ToolBox (2017). Density of Aqueous Solutions of Organic Substances as Sugars and Alcohols. [online] Available at: https://www.engineeringtoolbox.com/density-aqueous-solution-organic-sugar-alcohol-concentration-d_1954.html Accessed 04 March 2024.

You are looking for the light green line that ends up near a density of 1.45. This chart is for a mass percentage so both solute (sucrose) and solvent (water) have been weighed. The equation is:

(Mass solute / Mass solvent) x 100

Water has a density of 0.99819 grams per cubic centimetre at 20 C, so your density will be slightly off if you are measuring by volume (and can measure that precisely - most people can't without specialized lab equipment), the most precise way to measure would be to weigh out your water and sugar.

For a mass percent of 50 (i.e. 1:1 water to sucrose) the tables below the graphs on the linked page indicate 1.2295 grams per cubic centimetre (cubic centimetre approx = millilitre, as indicated above). For a 70% solution this changes to 1.3472 g/cc. It doesn't supply an exactly 66.6%, but you can extrapolate this from the graph to be around 1.33 (as also indicated in other answers).

Note that sugar has some solute volume; when it is dissolved in water it takes up some room. So, if you took 500 g of sugar and dissolved this in 500 ml of water, you might end up with (made up value) 700 ml of sugar solution. If you are making your solutions by dissolving in a smaller volume and then topping up to your nominal volume (e.g. dissolved 500 g in 300 ml, topped up to 500 for final volume), then your densities will be out by some factor. You could work the density out by converting the mass to molar concentration (molarity) using the following equations and then using the tables and/or graphs on the Engineering toobox linked above:

Number of moles = Mass (grams) / Molar mass (grams per mole)

Concentration (mol/litre) = Number of moles / volume (litres)

Sucrose has a molar mass of 342.30 grams per mole, so for 400 g in 500 ml final volume, you would have (400/342.3) 1.1686 moles in 500 ml (0.5 l) = (1.1686/0.5) = 2.3372 mol/litre. From the mol/litre graph; this would work out to be about 1.29, so somewhere between a 1:1 and a 2:1 solution. You could then take this value back to the weight percentage graph and read off on the percentage axis to get a weigh percentage of 61%.

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Here is the first Brix to specific gravity converter I found with a quick Google search. It indicates that 66.6 Brix is a SG of 1.33. I don’t think your way of calculating amounts for sugar syrup is correct —- the density of solutions is more complicated than that —- but that’s how you get density (i.e. specific gravity) from Brix.

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  • Specific gravity and density are two different consepts, although closely related. By density I mean the mass devided by the volume. So if I have a syrup of total mass M and total volume V, then the density D is D=M/V. The specific gravity is the density D devided by the density of some other thing (usually water) and is therefore a unitless quantity.
    – Vebjorn
    Commented Mar 1 at 22:06
  • Yeah I looked up the density of water and it turns out it’s just about “1”. What luck!
    – Sneftel
    Commented Mar 1 at 22:08
  • Seems like this could be for beer/ wine and not simple syrup? Because of the other ingredients in beer I don't know if this will be accurate... But thanks anyway! : )
    – Vebjorn
    Commented Mar 1 at 22:12
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    No. It’s for sugar in water. The contributions of other substances in wort and must are not significant enough to enter into the calculation. This is how Brix is defined.
    – Sneftel
    Commented Mar 1 at 22:14
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    @Vebjorn that works. I was supporting and expanding on "the density of solutions is more complicated than that" in the answer, which would affect plenty of related calculations
    – Chris H
    Commented Mar 3 at 8:25
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In the book Liquid Intellegence by Dave Arnold these values for the two densities are given:

Brix 66: 1.33g/mL

Brix 50: 1.23g/mL

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