- recipE -
- mussel shells
- 2% sodium hydroxide (NaOH) w/w solution with water
- clean the byssus
- remove the periostracum
- split ostracum from nacre
CLEAN THE BYSSUS
- Debeard the mussel removing the byssus with your fingers or with the help of a knife;
- Wash the byssus with soap trying to remove the bigger parts of shells remained attached;
- Leave the byssus dipped in vinegar for 3 days approx. to remove any residual fragments of shells. It turns lighter and golden in color;
- Rinse it again and let it air dry. You will get strong thin fibers.
REMOVE THE PERIOSTRACUM
To remove the dark layer that covers the shell, so that it is not burning in the next step of the processing:
- After cooking the mussels, clean the shells removing the muscle and any residual organic part with the help of a knife;
- Wearing gloves, in a basin prepare a sodium hydroxide solution weighing 0,2 parts of sodium hydroxide in 10 parts of water;
- Soak the shells and leave them 3-5 days in the solution. Water will turn darker as the periostracum pieces detach from the shells. The shells become more brittle;
- With the help of gloves and an abrasive pad remove the dark film that covers the shells and rinse them;
- Let the shells air dry;
- You can recover the periostracum film left in the solution using a strainer, rinsing it and letting it air dry.
SPLIT OSTRACUM FROM NACRE
- Place the shells on a baking tray;
- Cook the shells in oven at 250 °C for up to 3hours. The two layers turn progressively yellowish and more fragile until they split up;
- You can now collect them and process them separately as an option, using the nacre also for its iridescent properties.