Nc = mc
With Smin, we can get nc min :
Ncmin = mc
4 Mc p r 2 L 2 l (4/3)
With Smax, we can get nc max :
Ncmax = mc
2 Mc p r 2 L 2
Finally, if Nc > Nb, then the solution contains enough gelatine to form all the bubbles of foam.
L = 280 nm = 2,8. 10-7 m .
r = 5.10-5m
mc = 2/100*200 = 4g.
Mc = 3.104 g.mol-1.
l = 5.10-10m.
47 / 63
N c min = 34 1027
Nc max = 27.1015
In this example of foam, Nc max and Nc min are > to Nb, thus the quantity of gelatine introduced into
the solution was enough to disperse the totality of the bubbles of our foam in the solution.
The volume of foam is smaller than the theoretical maximum volume, that can be explained by a
lack of water or the possible presence of fats, particles, etc.
III.16.5.5. Discussion :
The foam sets, but its texture is too light to be able to be suitably cut. The mixture is very unstable
and the foam possesses big air bubbles (size reaching 3 to 4 mm of diameter). If the gel of gelatine is put
in the fridge, the gel would set and be firm.
In terms of taste, the infusion of a big hot pepper doesn’t give a taste strong enough. However, an
infusion of 1 big dried hot pepper and 2 small very strong hot peppers (finely chopped) in 500 g of water
gives an enough strong taste, in the Chef’s opinion.
Also, to get a lighter solution, we try to introduce a minimum quantity of gelatine into the tasty
III.16.6. Sugar in the highly seasoned preparation:
III.16.6.1. Material et method:
· 300 g of infusion of hot peppers,
· 6 g of gelatine
· 100 g of sugar.
Same method as in the lemon foam.
III.16.6.2. Results :
The foam sets, its texture is similar to the one of the lemon foam.
III.16.6.3. Discussion/ Interpretation :
In mouth, you get at first a sweet taste, directly followed by the hot of the pepper: this attack is
sudden and intense.
The hot part of the pepper taste is indeed weakened in this gel. However, to the Chef’s point of
view, the customers can’t appreciate this foam, because the first sweet taste does not warn about the