The proper thing for a packer of non-preservative catsup to do is to strike a happy medium on acidity; use enough vinegar to keep it under almost any conditions, but not so much as to almost entirely mask the tomato flavor and require sugar in such large quantity as to make the final product resemble tomato preserves. A good total acidity is 1.25%, figured as acetic acid. This figure includes both the acetic acidity of the vinegar and the natural acidity of the tomato. If a catsup is properly manufactured, this acidity should answer practically all purposes. The catsup packer should not be expected to make catsup which will keep in perfect condition in restaurants where absolutely no care or intelligence is used in handling it. This class of restaurant proprietor is fortunately in a decided minority, but rather than make a catsup that will be so strongly acid that it will stand up under his treatment, he should be educated to use a little care in the handling of the catsup.
The following is a common abuse in restaurants. We will say, for example, that three catsup bottles are on the tables containing from a half inch to two inches of catsup. The waitress does not like to put a bottle which is almost empty before a customer, so she pours the contents of two of the three bottles into the other one. The catsup in these bottles may be a week old. When the contents of the bottle containing this mixture are almost gone she pours the rest of it into another partly filled bottle and so on, so that some of the bottles may contain catsup which is over a month old, and in a warm, poorly ventilated restaurant it is apt to start fermenting. The proprietor should be educated to the fact that when using a non-preservative catsup he must not pour it from one bottle to another, but must leave it in the original container until almost gone, and then use the balance for making tomato sauce, spaghetti sauce, and for flavoring soups, gravies, etc.
One advantage the packer using benzoate of soda has over the non-preservative packer is that he can make his catsup so that it will keep properly and at the same time maintain the natural tomato flavor to a high degree. The tomato flavor is maintained because it is not largely masked by the use of a lot of vinegar and sugar. The packer using benzoate rarely uses more than a third as much vinegar or half as much sugar as the non-preservative packer.
Many non-preservative catsup makers who read this will think a total acidity of 1.25% is higher than necessary. They will say to themselves that the acidity on their catsup never runs over 1%, and they have never had any complaints. It may be that they do not have a very big restaurant trade where so many of the fermentation complaints come from, or that they do not have a very wide distribution of their product so that it is subjected to all sorts of climatic conditions, or it may be that they are having a case of fermentation now and then in households but never hear about it. In that case the housewife usually merely drops that brand and buys another one next time. But where a restaurant or hotel is having fermentation trouble, the manufacturer is sure to hear about it quick.
It is wise to allow a fair margin of safety, and my experience is that a total acidity of 1.25% is not too high. Quite a few catsup packers maintain an acidity between 1.50% and 1.75%, and one large concern has for years kept the acidity of their catsup around 2%. This, however, seems unnecessarily high. Acidity will be discussed further in the next chapter.
Processing Catsups
Non-preservative catsups should either be processed after filling and sealing, or the bottles should be sterilized before filling and the catsup filled very hot without giving an after-sterilization. Catsups made with the addition of benzoate of soda are not processed; however, the fact that benzoate is used should not cause laxness at any stage in the manufacturing process. It is a mistake for manufacturers to think that ⅒th of 1% of benzoate of soda will keep their product in perfect condition regardless of how careless they are in their manufacturing processes.
Advantage of Benzoate Catsups
Some brands of benzoate catsup enjoy a very good sale, and are popular with those who do not like a strongly acid and sugary catsup, but prefer one which is mild and in which the predominating flavor is one of tomato blended with mild spicing. A restaurant using a catsup or chili sauce of this character will almost always use more of it than they will of a strongly acid catsup which is highly spiced. If the catsup is mild, more of it is usually used at a time.