It is but natural that a product of this kind should vary greatly in flavor due to the selection and quantity of spices, salt, sugar, and vinegar used, and in consistency due to the degree of concentration and fineness with which the base has been comminuted. Most of the recipes for home-made ketchup call for rather liberal spicing and long cooking so that they have a fairly heavy body. These insure good keeping quality, but impart a dark color to the product.
The manufacture of ketchup upon a large commercial scale is of rather recent development and is confined almost wholly to the use of tomatoes as a base. There was little ketchup of the kind best known at present made prior to 1890, as most ketchup was made by what was known as the natural fermentation method, that is, allowing the tomato pulp to ferment spontaneously and using the solid portion for stock. This method was continued, though on a decreasing scale, until 1908, at which time it was practically prohibited. Beginning about 1890, ketchup was made from fresh pulp and barrel stock without fermentation, the fermentation being prevented by the use of a preservative. The method is still in use. The first extensive manufacture of non-preservative ketchup began about 1908, though a few firms had been making it prior to that time, the pioneer probably being E. C. Hazard, of Shrewsbury, New Jersey.
From the amount of space given to the subject of ketchup in the canning and food journals, one might conclude that it is a difficult product to make, or that it is one of very great importance. It is in reality very easy to produce, but has assumed a prominence among food subjects which it does not deserve, due to the fact that some manufacturers have not yet learned the necessity for using care, or persist in using material of questionable quality.
Ketchup is made in the home with very simple apparatus; a colander or sieve for breaking and straining the pulp, and a copper, porcelain, or earthen kettle for cooking, being all that is necessary. The cooking of the tomatoes with the spices, sugar, vinegar, etc., is generally done slowly, until a heavy body is obtained, which results in a dark color, but insures sterility of the product when it goes into the container, and also contributes to keeping quality after it is opened. In the factory many refinements are necessary to make a commercial article which will attract the eye as well as satisfy the sense of taste. The usual dark colored, rough, home-made article will not command a sale over a grocer’s counter alongside of that made in a modern commercial kitchen. Here, sorting tables, washing machine, scalder, cyclone for pulping, steam-jacketed kettle, tanks with coils, or vacuum pan for cooking, finishing machine, bottle washing, and filling machine, are all necessary. The pipes carrying the pulp from one machine or vat to another must be enameled, bronze, tin-lined, or silver-plated to prevent the fruit juice from coming in contact with iron or anything which will cause discoloration. The work is done speedily, and the cooking done in the shortest possible time in order to secure the brightest color and smoothest consistency.