Two ounces and a half of Cayenne pepper, 1-1/2 lbs. of bay salt, 8 lbs. of mustard flour, and 1-1/2 lbs. of wheaten flour, made into a stiff paste, with the requisite quantity of water, in which the bay-salt is previously dissolved, forms the so-called _genuine Durham mustard_, sold in pots. The salt and Cayenne pepper contribute materially to the keeping of ready-made mustard.
There is therefore nothing deleterious in the usual practice of adulterating this commodity of the table. The fraud only tends to deteriorate the quality and flavour of the genuine article itself.
It is well known to every one, that the expressed juice of lemons is extremely apt to spoil, on account of the sugar, mucilage, and extractive matter which it contains; and hence various means have been practised, with the intention of rendering it less perishable, and less bulky. The juice has been evaporated to the consistence of rob; but this always gives an unpleasant empyreumatic taste, and does not separate the foreign matters, so that it is still apt to spoil when agitated on board of ship in tropical climates. It has been exposed to frost, and part of the water removed under the form of ice; but this is liable to all the former objections; and, besides, where lemons are produced in sufficient quantity, there is not a sufficient degree of cold. The addition of a portion of spirit to the inspissated juice, separates the mucilage, but not the extractive matter and the sugar. By means, however, of separating the foreign matters associated with it, in the juice, by chemical processes unnecessary to be detailed here, citric acid is now manufactured, perfectly pure, and in a crystallised form, and is sold under the name of concrete lemon acid. In this state it is extremely convenient, both for domestic and medicinal purposes. One drachm, when dissolved in one ounce of water, is equal in strength to a like bulk of fresh lemon juice. To communicate the lemon flavour, it is only necessary to rub a lump of sugar on the rind of a lemon to become impregnated with a portion of the essential oil of the fruit, and to add the sugar to the lemonade, negus, punch, shrub, jellies or culinary sauces, prepared with the pure citric acid.