THE MANUFACTURE OF TOMATO PRODUCTS TEXT

tossed in the center and is never looked at again except by the final inspector. If bad, the good part is thrown in the center and the bad allowed to remain on the outside, to be conducted to the waste barrel. All the sorters except the first four can spend their entire time working on tomatoes which need to have bad parts cut out of them. The main objection which is made to the divided belt system is that the first four women get careless and throw unsound tomatoes into the center partition and they are never looked at again. However, if care is used in the selection of these women, and a reliable sorter is placed at the end of the belt to inspect the center partition before it leaves the belt, such carelessness can be checked and held down to a minimum. Another objection that is advanced is that there is the possibility of partly good tomatoes going into the waste barrels due to the fact that the women might not always keep up on them. In my experience with the system I have had practically no trouble in this regard. If a long belt is used, as many trimmers as desired can be put on, and the belt can be slowed down or the rate at which it is fed slowed up if the tomatoes are running particularly bad. Then, in extreme cases, it is always possible to have someone go over the waste barrels before they are dumped. An average grade of tomatoes can be handled quite rapidly by the divided belt system. Some packers who have used it several seasons like it very much, and an analysis of their product will generally show a low count of molds, yeasts and spores, and bacteria. I understand, also, that other packers that have used the method have discarded it. Sorting By far the greater part of the trouble packers have with their goods not complying with the government regulations as to molds, yeasts and spores, and bacteria is due to inadequate sorting. At least ninety per cent of this trouble could be overcome right at the sorting belt. Packers often say they can’t understand why the mold is running high on their pulp and catsup, as they are sorting their tomatoes carefully. However, the chances are ten to one the trouble is they are not sorting them carefully enough. One who has not had much experience managing help on the tomato sorting belt would imagine that almost any woman could step up there and sort out the good tomatoes from the bad, and know what to cut out, and what not to cut out. But such is not the case. The tomato sorters must be instructed. Someone who is competent to do so must work with each one of them and show them just what is a good tomato and what is not. Otherwise they will be spending part of their time cutting out black, fibrous growths on the surface of the tomatoes which are absolutely normal and entirely free from molds, etc., and allowing tomatoes to pass by them which have black spots on the surface no bigger than a dime, but indicating to the trained eye that probably half of the tomato is eaten up with black rot. They will allow a tomato to pass by which is cracked open, and the edge of the skin on each side of the crack will be as white as a piece of paper. Unless they are instructed, they may not realize that this is mold, and they certainly will not realize the amount of damage a small percentage of tomatoes like that can do. They know nothing about mold counts, but most women can be impressed with the importance of watching for moldy streaks and spots in mashed and split tomatoes, and the importance of eliminating every bit of tomato tissue that is so effected. Every sorting belt should have a boss—a competent sorter who knows his or her business, and who stands at the end of the belt and inspects the tomatoes just as they are about to leave the belt. This person can order the speed at which the tomatoes are fed to the sorters increased or decreased according to the quality, can see just what form of decay is predominating and caution the sorters to watch out for it, can see the mistakes that are being made in the sorting and try to correct them, and in addition can throw out into a receptacle such bad tomatoes as have passed by the sorters so that they can be sorted over again. It is not safe to put a bunch of women on the sorting belt with no one in authority who is on that particular job every minute, and expect an entire day’s run to come within the government limits. Forms of Decay There are many forms of rot, but the most common are the black rot, soft rot, and the mold growths in cracked tomatoes, either those which have cracked deeply around the stem end during their growth, or have been cracked or mashed in shipment. Just as soon as the skin is broken, either in a natural or unnatural way, molds start growing on that broken surface immediately, and develop very rapidly. There is also the brown spotted tomato, which is not so common, but which has been very bad in some localities. I remember one field of tomatoes in southern Ohio several years ago which was absolutely worthless for canning purposes, due to the fact that practically all of the tomatoes were covered with brown spots, and under each one of these spots was a lump of white mold and mold spores. This field was plowed up before half of the tomatoes were picked, as the pulp plant which had contracted them refused to receive any more after having cooked several batches of pulp on which the mold ran very high due to this condition, which had never been met with before. The brown spots were soft and concave, and if once the character of the spot was fixed in the memory one could never fail to quickly detect that type of tomato if it was run across again. The disease appeared in both central and southern Indiana the following year and I sent samples of the tomatoes to the Department of Agriculture at Washington and to the Indiana state experiment station, but it was new to them and they had no remedy for it. Whether it has appeared since I do not know, but it was very bad while it lasted. It is almost impossible to sort such tomatoes, as the spots are so numerous on the surface, and every spot would have to be cut out. When the spots are small, as they frequently are, they are very apt to pass by the sorters unnoticed, or at any rate considered harmless, but it doesn’t take many bushels of such tomatoes to send a batch over the limit in mold count. Extremely soft spots which will yield to very slight pressure with the finger are usually receptacles for the growth of yeasts and bacteria and should be cut out. Nine times out of ten such spots are offensive to the nose when the skin of the tomato is broken. However, one quickly learns to pick them out by sight. It is important that the sorting belt be well lighted with 100–watt lamps overhead provided with large reflectors. On dark days good sorting is impossible unless the belt is adequately lighted, and, of course, for sorting in the early morning or late evening adequate light is absolutely essential. Cleanliness of Equipment To dwell upon the necessity of thoroughly cleaning all washing and sorting equipment each night, as well as to frequently change the water in water baths, in case a water bath is used, would seem almost unnecessary, yet there are many packers who do not comprehend the trouble that can be caused by inadequate cleaning of the washing, sorting, and conveying equipment. Does the sorting and washing equipment in every pulp plant impart a clean, fresh, sweet smell when the morning’s work is begun? It does not, and the reason is that it was not properly cleaned the night before. Those surfaces which were easy to get at and which are easily seen in a hasty inspection are clean, of course, but how about the dark corners and almost inaccessible places that are hard to clean? Can you run your fingernail over the surface of one of the bucket conveyors, or “flights,” for example, and scrape off a thin, slimy film? If you can, you can be sure it is mold, and that the only way to get it off is with a very stiff brush—even a wire one may be necessary—hot water, and soda ash. If the bucket conveyors or “flights” are covered with a thin film of mold, the tomatoes will carry along a small part of this mold with them every time the conveyor is used, and as fast as the mold is rubbed off the conveyor by the tomatoes more mold will grow on again. The same care should be taken with this equipment as is given to the equipment in a milk bottling or condensing plant. My experience has been that the only safe way to check up the thoroughness of the cleaning job is to go over it with a spot light, with particular attention to the most inaccessible parts, and to do everything possible to make every part of the equipment accessible. Molds, Yeasts and Spores, and Bacteria 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. Some packers object to brass and copper coming in contact with the tomatoes on account of the slight amount of copper which goes into solution by the action of the tomato acid. In the case of the “breaking tank,” however, the few short brass pipes offer a very small surface to the action of the tomato acid, and the amount of metal dissolved would be negligible. These brass pipes can be plated with tin if it is desired to avoid contact with brass altogether, and this is frequently done. Advantages Claimed for Hot Pulping Those who use the hot pulping method like it for a number of reasons. In the first place, the tomatoes are brought to a boil while they are still whole, and this eliminates any chance of fermentation due to the crushing of the tomatoes before they are cooked. By bringing the tomatoes to a boil quickly, that is, as soon as the washing and sorting is completed, any incipient fermentation is arrested immediately. As the tomato juice is near the boiling point when it is cycloned and delivered to the cooking kettles, no multiplication of yeasts, bacteria, etc. can take place between the sorting and the final condensing, unless the juice is allowed to cool considerably at some point between the “breaking tank” and the cooking kettle. Another advantage claimed for the hot process is that the pulp of the tomato is more completely separated from the seed and skin than when the tomatoes are pulped cold, and therefore the tomatoes will give a slightly larger yield of pulp. It is also claimed that a better color can be obtained by the hot pulping process, as the color cells of the tomato lie in greatest abundance directly next to the skin, and by making a clean cut separation of the skin from these color cells by boiling in a “breaking tank,” none of this color will be lost in the pumice during the cycloning. Although this argument does appear reasonable, I have failed to see that tomatoes which are pulped by the hot process give any better color than those which are pulped cold. The hot process is also liked where the tomatoes are to be manufactured directly into catsup or tomato soup, as the “breaking tank” can be filled up to a certain mark with the boiling tomatoes and that gives the measure of tomatoes for the catsup or soup batch, and no other measuring devices for this purpose need be employed. Objections to Hot Process The chief objection to the hot process is that it requires a lot of additional tanks for breaking the tomatoes, which are entirely dispensed with when cold pulping is used. The tanks are not only an additional expense to the equipment, but require one or two operators to tend to them, and they take up a lot of room, and consume a lot of steam. No seed can be saved from tomatoes which are pulped hot, as the cooking either kills the germ or renders it impotent. Quite a few canners save the seed from cold pulped tomatoes, and the revenue from it proves to be a profitable item. As to whether the slightly increased yield to be obtained by the hot pulping method, and the decreased danger of multiplication of yeasts and bacteria, more than compensate for the advantages to be obtained by the cold process is a question which the individual packer must decide for himself. Crushing Crushing the tomatoes without cycloning them is a very good method where the tomatoes are going to be made into pulp or puree, as the finishing machine will convert the crushed cooked tomatoes into a very smooth product. Where catsup is to be made direct from the tomatoes, however, cycloning is to be preferred to crushing. If the final product is to be soup, cycloning is necessary. This will be discussed further in the chapters on catsup and soup. When a crusher is used it takes the place of the cyclone or pulp machine, although it performs an entirely different kind of an operation, and the tomatoes go through exactly the same process as in cold pulping, except that instead of removing the seeds and skins from the tomatoes before cooking, the tomatoes are chopped very fine and conveyed to the cooking kettles—seeds, skin and all. It is obviously somewhat harder to gauge the finishing point of a batch of pulp where the skins and seeds are present, however a little practice largely eliminates this difficulty, and there is always the method of determining the specific gravity by weight to fall back on. The seeds and skins will not interfere with making the specific gravity test as it is usually carried out in the cook room with a large copper flask, small trip balance, and set of weights. Conveying to Kettle If the plant is so arranged that the pulped or crushed tomatoes can be conveyed to the cooking kettles by gravity, that is an advantage, as it does away with a pump and someone to tend to it, and the fewer the pumps, the better; however, in most plants it is necessary to pump the pulped or crushed stock into the cooking kettles. Unless the plant consists of several floors and the tomatoes start at the top and come out as finished pulp at the bottom, or the plant is built on a terraced plan, as one plant is in Indiana, which is built on the side of a hill, it is necessary to do a certain amount of pumping. An ordinary pump will not do, as there would be contamination by iron, and considerable rusting, while the pump was idle, of those parts of the pump with which tomato juice comes in contact, this rust to be carried along with the tomato juice the first time the pump is used again. The rotary pump constructed partly of bronze or nickel is very good for this purpose, and offers as little opportunity for metallic contamination as any pump does. The pipe used for the conveying of this tomato stock should by all means be enamel lined. Enamel lined pipe, if properly made, will last for many years without chipping or cracking. Just how long it will last on the average I cannot say, but I have often taken down lines of enamel lined pipe that have been in use for several years, and it looked practically as good as new. The flanged pipe with flanged fittings is better than that with the ordinary screw ends, as it makes practically a continuous white tube without any pipe threads in which molds, yeasts, and bacteria can lodge and multiply. Wooden troughs are still used in many plants for conveying tomato juice and pulp, but they are a relic of the old days, and have no place in the modern pulp or catsup plant. Wooden troughs are hard to keep clean, they mold very quickly after they become damp, they are open to contamination from ceilings and roofs which aren’t always in good condition, and they are usually wasteful. It will pay any packer who still uses even a few wooden troughs to invest in enamel lined pipe. Wooden pipe is also unsanitary for this purpose, as mold grows in it and clings so tightly to the porous, damp surface that it cannot possibly be flushed out. Value of Pumice This chapter, which deals principally with cycloning, seems to be a fitting place to discuss the value of the pumice which comes as a waste product from the cyclone. Although it has been repeatedly demonstrated by chemical analysis that this pumice or tomato waste is a valuable by-product, every time the question has come up of its utilization and preparation into a salable product or products, the decision has been that the expense involved would be too great to make it pay. This by-product is profitably handled in Italy, producing an oil of commercial value, and an oil cake which is used for stock feed; however, the conditions in Italy and in this country are very different. In the Parma district of Italy there are forty factories very close together,