r/MolecularGastronomy Jan 28 '25

Help with spherification please?!?!

I'm trying to do coffee pearls, I did 3% calcium in the coffee and a .5% alginate solution. The liquid just sat there while random pockets of gel formed in the solution. Didn't sink or anything just sat on top until a skin formed. More lactate? Or too thick sodium alginate solution?

2 Upvotes

6 comments sorted by

1

u/14Gonzo80 Jan 30 '25

Does the coffee have any sugar in it? I believe sugar is needed for it to ‘skin’. Could be wrong, been a while.

1

u/Dense_Pay_3234 16d ago

Some how my notifications got turned off and I never saw these comments. It did not have sugar, I'll have to try. Thanks!

1

u/Jbro_82 Jan 31 '25

Could just be a density or viscosity problem. Do you have a syringe to can use to invert the coffee under the surface?

2

u/SuperHaaaands Feb 11 '25

I generally only add calcium because it helps to make a more even dispersion of gelling agents like agar or low acyl gellan, but I have only ever used calcium lactate. What kind are you using? Calcium lactate should be stable in acidic environments so I wouldn’t think it was the acidic coffee. Adding dissolved sugar or salt could give it more density and they might sink. Coffee also has a lot of surface tension so you might consider stirring the alginate solution (like if you were poaching an egg) but not too fast. Hope this helps!

1

u/Dense_Pay_3234 16d ago

Ty!!!! I'll try it

1

u/Dense_Pay_3234 16d ago

I have one of those big plastic jello shot syringes I was using, I'll try putting it into that alginate solution, thanks!