Gagnaire cites my participation (appendix X).
Figure 34 : lemon foam whisking
Figure 35 : Lemon foam after 2 hours in the fridge
Figure 36 : A quenelle of lemon foam.
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III.16.5. Highly seasoned foam:
We would like to obtain jellified foams that we can cut into different shapes. Here, we try to get
salted jellified foam with the taste of hot pepper. As a matter of fact, gelatine and foam lower taste. The
idea is to temper a hot and spicy taste, such as hot pepper, by the mean of jellified foam.
III.16.5.2. Materials and method:
• 1 dried hot pepper (10 g are infused in 500 g of boiling water).
• 200 g of the hot peppers infusion, filtered in a conical strainer.
• 5 g of gelatine,
• 2 pinches of salt
The protocol is the same as in the previous experiments.
With 200 ml of water with 5g of gelatine (solution at 2.5 % of gelatine), the mixture allows to make
about 1.5 l of jellified foam after whisking 25 min (on ice). This foam is not enough firm and some bubbles
(their size can reach 4 mm of diameter) can appear when you stop whisking.
III.16.5.4. Calculations: use of the formalism of dispersed systems.
III.126.96.36.199. Bubbles of the jellified foam:
Let Vi be the initial volume of the solution that is used to make the foam.
Let Vf be the final volume of the foam.
The size of a bubble in foam (made with a fork) is by hypothesis, equal to 10-4 in 10-5 m of
Let Sb be the surface of a bubble (in foam):
Sb = 4 p r 2
Let Vb be the average volume of a bubble:
Vb = 4
p r 4
Let Nb be the average number of bubbles in Vb:
Nb = 3 (Vf - Vi)
4 p r 4
Numerical application for our example:
Vi = 0,2 L = 2.10-4 m3.
Vf = 1,56 L = 1,56.10-3 m3.
r = 5.10-5 m.
Nb = 51.6 1012.
III.188.8.131.52. The fibres of collagen:
The collagen is a protein from cartilaginous and muscular tissues. In muscular tissues, the
collagen represents between 20 and 25 % of the total proteins.
The collagen is made of a triple peptidique chain, among which each possesses a helical
structure and form a triple helix by hydrogen boundings.