Martin over at blog.khymos.org has put together a revised collection of information on
hydrocolloids. It is a fantastic resource that keeps getting better. One thing he's trying to do is gather up densities for various elements used to create hydrocolloids (suspensions, gels, spherification), so as to allow more people to experiment with molecular gastronomy techniques through volumetric measurement (most people don't have high precision scales sitting around, so being able to use a teaspoon improves convenience).
Anyway, I wanted to contribute to this effort so took an hour to weigh some of the chemicals in my pantry. I used a 50g limit scale with 0.01g accuracy, and a childrens plastic medicine cup for the container. I've also noted the texture / consistency of each material, as it seems some will have greater variation than others when volumetrically measured (when I say sticky below, the substance tends to cling to the container's outside a bit, I brushed this off). I followed the steps to measure outlined on
blog.khymos.org. These densities are meant to supplement Martins document
here, specifically the table on page 60 in the appendix. If you happen to have some sodium alginate laying around the house, please take 10 minutes to weigh it as outlined, and help demystify these techniques for other would-be molecular cuisine people out there.
Sample container empty weight 2.66g
Sample container filled with water 29.12g
Inferred volume of sample container 26.46 ml
Sodium Citrate samples (gross) - 31.33g, 31.21g, 31.36g
average net sample weight - 28.67g
inferred density - 1.08352 g / ml
notes: not sticky, evenly sized crystals
brand:
willpowder.netCalcium Lactate samples (gross) - 20.92g, 20.82g, 20.93g
average net sample weight - 18.23g
inferred density - 0.68896 g / ml
notes: sticky, powder that when agitated is dusty
brand:
willpowder.net Calcium Chloride samples - 23.82g, 23.87g, 24.01g, 23.95g
average net sample weight - 21.2525g
inferred density - 0.803193 g / ml
notes: very uneven spherical granules, some stickiness
brand:
willpowder.netCalcium Lactate Gluconate samples - 17.90g, 18.07g, 17.88g
average net sample weight - 15.29g
inferred density - 0.577853 g / ml
notes: sticky and easily compacted powder, dusty when agitated
brand:
willpowder.netGuar Gum samples - 18.69g, 18.80g, 18.66g
average net sample weight - 16.056667
inferred density - 0.60683 g / ml
notes: very fine powder, not sticky
brand: bulk (
vitamin cottage)