The clarification of this jelly is carried out using 4 egg whites per 5 litres (8¾ pt or 1⅜ U.S. gal) of the Fish Stock. During the clarification of this jelly it frequently happens that the wine breaks down precipitating certain colouring matter of tannic origin. It would appear that this is provoked by the contact of the wine with the gelatine suspensed in the stock and up to now there seems to be no way of preventing this.
It is therefore necessary to compensate for the absence of colouring matter by the addition of artificial or red vegetable colouring. This must be used with the greatest possible care so as to ensure that the colour of the jelly is no more than a fight delicate pink.