The Manufacture of Tomato Products / Including whole tomato pulp or puree, tomato catsup, chili sauce, tomato soup, trimming pulp

by W. G. Hier

Cypress Tank

Cypress tanks should be constructed of 2–inch material and made with a sloping or concave bottom, preferably the latter. They will not impart any foreign taste to the product, as is sometimes thought, even after becoming charred by long usage, and if kept clean they will remain sweet as long as they are kept in continuous use. A musty taste is sometimes imparted to pulp or catsup cooked in a cypress tank if it has been standing idle for a long time and is not thoroughly cleaned and boiled out with soda before it is used again. Cypress tanks have the advantage of being cheap, and also of having large cooking capacity.

Cleaning Kettles

Cooking tanks and kettles should be cleaned thoroughly after every batch. If the steam trap is working properly the burning on the coils and sides of the kettle will be so slight that almost all of it can be washed off with the hose if the water pressure is strong and the hose is bushed down to one-eighth inch. The best things to use to take off the material which burns on hard and black is a pot chain for coils, and for the jacketed kettles a wire brush or very stiff fiber brush does very well. If any of the baked on pulp is not removed before the next batch is cooked it will interfere with the cooking by lengthening the time required to finish the batch, and by causing the coils to burn still harder next time. The cook should be instructed to get down in the tanks frequently, and feel underneath his coils to see that they are properly cleaned. The manager should also make it a point to do this several times a day. His quality will depend in no small degree on the way his coils are cleaned.

Coil Leaks

Leaks in coils should be attended to immediately, as they cut down the available steam pressure, and soon become so large that it becomes impossible to cook satisfactorily. An ordinary soldering job will only hold them for a day or two, and it is necessary to take out the coil and braze it if the leak is to be permanently mended.

Starting the Cooking

We will say that we are now pumping over the cycloned or crushed tomatoes into the cooking kettle. Some packers pour a cupful of cottonseed oil in the kettle to assist in breaking the boil, others rub the sides of the kettle with fat, such as a piece of cocoa butter, while others use no oil or fat at all, but take care to feed the kettle slowly and carefully, and cut the foam with a sharp spray of water from the hose to assist in breaking the boil. The oil or fat does seem to help some, but it is not necessary if the kettle is fed carefully. As soon as the coil or jacket is covered the steam can be turned on full; however, the exhaust should be opened immediately, and not closed until all the condensation which has collected in the coil or jacket runs out and the steam comes through perfectly dry. The condensation of the pulp should then be conducted as rapidly as possible, pumping over more of the tomato juice as the kettle is able to take care of it, and boiling continuously. The eye soon learns to judge the approach of the finishing point, and then the exact finishing point must be determined. There are many ways of doing this, and a number of ways have been recommended. No method can succeed which is not simple and quick, and which offers scarcely any chance for error when used by a cook, whom, it must be remembered, is a man of very ordinary intelligence.

Methods of Gauging Finishing Point

The simplest method is gauging the finishing point by the eye, but this method is also the least accurate in the hands of the average cook. Cooks who have had years of experience with tomato pulp sometimes get to be very expert in gauging the finishing point by the eye, and can determine it with surprising accuracy. Such a cook is the exception, however, and most packers have to use some sort of a mechanical method by which at least fair accuracy can be counted on. These methods consist of: first, condensing the pulp to a certain mark on the kettle, a definite volume of juice having been taken to start with; second, cooking a certain length of time; third, determining the specific gravity of the hot pulp by weighing a definite quantity on a small balance; fourth, estimating the gravity by the use of a hydrometer.