Pulp packed in No. 10 and No. 1 cans is usually filled with a rotary filling machine, although No. 10’s are often filled from a single line pipe and the filling can be done quite rapidly where the operator is expert at the job. If it is necessary to top any of the cans, it should be done from a small jacketed kettle which is connected up near the filler, so that the pulp used for topping can be kept hot. The cans should be put through a can washer and steamer before filling.
No. 1 pulp should have a much larger call from the consumer than it has, and it could be made very popular if a high standard of quality was set and maintained, and the advantage of its use advertised to the housewife. Many consumers who have purchased the small size pulp or puree for use in making tomato sauce, spaghetti, tomato soup, etc., have been disappointed in the quality, and after one trial have gone back to canned tomatoes for these purposes.
For No. 10’s a process in boiling water of 40 minutes in the old style straight process tank is usually considered sufficient; this is to be followed by a very gradual cooling in water so that the cans will not buckle badly. For the No. 1 size a 20–minute process in boiling water is sufficient. It is always well to cool the cans about ten minutes so they will not retain the heat a great length of time. A better color and flavor can be maintained if the goods are cooled in water after processing. If a continuous agitating cooker is used for processing the lengths of time given above can be cut down at least 60 per cent.
Packing Barrel Pulp
Barrel pulp is scarcely being packed any more, as the barrel has shown itself to be unfit for pulp which is packed without preservative. The use of barrels today is usually only resorted to in emergency cases when cans for the purpose are not available. If the pulp is to undergo long storage and shipment, or any great amount of handling, barrel goods will usually show quite a big loss, not only because much of the pulp is spoiled so that the spoilage is evident at once upon inspection, but because of the growth of yeasts and bacteria in the pulp while it has been in storage, and because of loss of color due to the action of air seeping into the barrel. Wooden barrels as a rule are not absolutely air tight, and it is hard to make them so.
I have packed pulp in good uncharred whisky barrels, using 5 lbs. of salt to the barrel, and rolled the barrels to a sheltered place where they would not be disturbed until they were ready to open, and after two or three months’ storage the pulp was all right. If this pulp had been moved, or held until a spell of warm weather came on, it is doubtful if it would have shown up so well. The barrels should be washed out well and steamed for about five minutes before being filled, and the bungs should be burlapped.
Metal Drums
Ingot iron drums, such as are used for shipping oil, have been recommended for tomato pulp and I have tried them, but they will not do, as the tomato acid dissolves too much of the iron.
A Method of Preserving Pulp in Barrels
As a method of preserving pulp in barrels one packer for a number of years put hydrochloric acid in it. This, being a strong acid, is also quite a good preservative, and evidently kept the pulp in good shape. When the pulp was worked up, enough bicarbonate of soda was added to neutralize this acid, and the result of the neutralization was sodium chloride, or common salt. There evidently could be no objection made to this from a pure food standpoint, as none of the acid was left in the pulp after the neutralization, and sodium chloride is a common ingredient of pulp. However, the process darkened the pulp, which was an objection. As to whether or not the flavor was impaired by this treatment I do not know.