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

by W. G. Hier

An understanding of the nature of molds, yeasts and spores, and bacteria is very helpful to any packer. A knowledge of the rapidity of their growth and the conditions under which they multiply most rapidly is also helpful. The average packer has a very vague idea of this subject, yet it is easy of comprehension. In CHAPTER VII a discussion of it will be found, which it is hoped will help to clear up the misty atmosphere surrounding this subject, and in the same chapter the government attitude toward micro-organisms is also discussed.

CHAPTER III
PRINCIPAL METHODS IN USE FOR PULPING

The chief methods in use for preparing the tomatoes for the cooking kettle are: first, cold pulping; second, hot pulping; third, crushing without cycloning.

Cold Pulping

The cold pulping method is probably the most common, and requires less equipment than the hot method, with results that are considered by many packers just as good, if the pulp machine is operated by a careful man who will not feed it too fast, and who will keep it clean. Sometimes, with this method, the tomatoes are run through a crusher before pulping, and sometimes not.

Care of Cyclone

It is important that the outlet from the receiving box under the cyclone be directly from the bottom, and not from the side of the box near the bottom. The box must drain completely so as not to leave any tomato juice lying in it to ferment. A tapering enamel lined receptacle which drains itself completely is best to use under the cyclone.

The steam hose should be turned into both the cyclone and receiving box several times during the day to arrest growths of micro-organisms, and clean out adhering tomato fiber. It is particularly important to do this just before the noon hour, as considerable fermentation can take place in the cyclone during that hour if it is not cleaned out beforehand.

Hot Pulping

By the hot pulping method the tomatoes are conveyed, usually by means of a series of “flights,” or a bucket conveyor, to “breaking tanks” which are arranged above the cyclones. These “breaking tanks” hold about 1000 gallons, and are usually constructed of cypress. At the bottom of the tank are open brass steam pipes running horizontally in four directions. These pipes are about two feet in length, and are open at the ends so that the steam comes directly in contact with the tomatoes. The tomatoes are conveyed direct from the sorting belt to the “breaking tanks,” and as soon as the brass pipes are covered the steam is turned on full and the breaking up process begins. It usually takes about 30 minutes to break up the tomatoes, and they are then cycloned. The tank should have a concave bottom and large outlet, preferably 3 inch, so that the broken up tomatoes can be let out of the tank easily. Iron pipes should, of course, be avoided, as the acid of the tomato attacks the iron, producing an iron salt which is apt to discolor the product, particularly if it is to be used for catsup, and this dissolved iron comes in contact with the tannic acid of the spices. This will be discussed further under the manufacture of catsup.