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been chilled on the farm; therefore, its bacterial content has increased beyond the point at which Pasteurization is sufficient to make it safe. The temperature of the milk which is received from shipping stations is usually about 50° F., and not more than 55° F. Unfortunately much of the milk coming in by train reaches the city at a higher temperature than this. While the producer must accept responsibility if he has not properly chilled his milk, yet we appreciate the fact that inadequate service on the railways-delay, lack of refrigerator cars and of proper loading platforms—means that a great deal of the milk reaches the city at too high a temperature.

Milk should not under any consideration be received that has been shipped any distance at a temperature over 70° F. However, in many places where there are not proper shipping facilities this will always be a weak link in the system of control.

The third test that is made is for butterfat. Samples of milk are taken from the original cans after careful mixing, and are tested at the laboratory for butterfat and total solids. When there is any occasion for it, tests are also made for preservatives and any adulteration. Fortunately these last two are almost things of the past in Toronto's supply.

The fourth test is made for the bacterial content. Samples are taken, using all precautions to prevent infection, and these are plated in the laboratory. These tests are all made at the laboratory, and the reports of the farm inspector, the dairy inspector, and the laboratory division are all correlated.

When it is found that a farmer is shipping milk that is dirty or below standard, his supply is promptly excluded and not readmitted until he comes up to the standard and in every way complies with the requirements of the department. This is probably the most efficient way of compelling producers promptly to comply with the requirements of a department of public health.

A record of each producer should be kept at the central office, on which should be entered the results of such tests as are taken. In this way the man's past record is available at a glance, and any tendency to slip back after he has had a record of constant improvement can be promptly detected. The same records can also be used for the farm inspectors' reports. In this way the farm inspector before making his inspection, has available all information regarding the cleanliness or lack of cleanliness, and the quality of milk produced; and the head of the division is also in a position to direct the attention of the inspector to all farms from which contaminated milk is shipped.

In the city itself the dairies should be under the constant supervision of a staff of city inspectors. Particular attention should be paid to the general cleanliness of the plant, the thorough cleansing and sterilizing of all apparatus used in handling the supply; piping should be taken down and pumps taken apart from time to time, and all possible lodging places of dirt or bacteria sought. The method of sterilizing apparatus and utensils must also be carefully checked, both practically and experimentally.

The necessity for the installation of self-registering thermometers of a reliable make was fully appreciated when it was found that many dairymen apparently did not realize the necessity for the proper control of their Pasteurizers. Temperatures ranging from

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115° to 160°, and a holding period from five minutes to two hours were found. Occasionally our inspectors found men beginning to bottle as soon as their thermometers had reached a temperature of approximately 140°. Consequently the contents of the last few bottles might have been Pasteurized within the accepted meaning of this term, but certainly the great bulk of the milk in the Pasteurizer had been bottled with a maximum holding time of less than 15 minutes. We have now eliminated all possibilities of these irregularities by the installation of self-registering thermometers.

The sterilizing of the coolers and bottle fillers should be closely supervised, and frequent samples should be taken to control the possibility of contamination of the milk subsequent to Pasteurization. To reduce this to a minimum the capping of the bottles must be done mechanically and not by hand. This will remove one most probable source of infection (the human hands) subsequent to Pasteurization.

The adequate supervision of Pasteurization and the subsequent handling of the milk are operations to which the attention of the inspectors must be especially directed. It is to be regretted that, as vet, there is no form of capper available which puts a cover over the top of the bottle, as is done with certified milk, at a cost which would not be prohibitive as applied to the general supply of a large city. The danger of infection of the neck of the bottle or the lip of the bottle with the present type of cap is a real one. Some few outbreaks of communicable disease have been traced to this source.

The milk cans and bottles, when ready to receive milk, are frequently tested by our inspectors. A small quantity of sterile water is poured into the can or bottle; it is then agitated thoroughly; these samples are then poured into sterilized bottles, properly capped, and returned for examination to the laboratory.

When unsatisfactory conditions are found in a dairy, special inspections should be made, and it is usually possible to locate the source of the trouble without a very extended inspection. Dairies, as a whole, will be found to respond very well to the efforts of a department of health, and usually they will take adequate steps to protect their own milk supply, both before and after delivery at the plant.

Inspections should also be made of the wagons in which milk is delivered and of the stores in which it is sold, as only bottled milk should be allowed to be sold. Such inspection can usually be confined to the way in which milk is handled and its refrigeration, although it is sometimes advisable to take samples from bottles to male sure that the same supply is being issued for store distribution as for home delivery.

The milk sold in restaurants requires careful watching. Of course in the better restaurants milk is sold in half-pint or pint bottles, so that the consumer is assured of getting whole milk. In other restaurants, however, the milk is dispensed from a can or through an urn. Unless the contents are frequently and thoroughly stirred, the cream separates, and the last customer gets a much richer milk than the first. There will always be difficulty under these conditions in having the milk frequently stirred before serving. However, a few police court proceedings will usually correct such difficulty.

THE CARE OF THE MILK IN THE HOME.

It must be apparent that, notwithstanding the fact that milk may be delivered to the home clean, absolutely free from barnyard contamination, and made safe by scientific Pasteurization, carelessness in the handling of the milk in the home may make the milk unfit for human consunption inside of 12 hours.

The milk bottle, when taken in, should be carefully washed with warm water and wiped with a clean cloth. After the necessary amount is taken out for use, the remainder should be placed in a refrigerator. In cases where a refrigerator is not available, an improvised ice box can always be made for a few cents. Otherwise the milk may be placed so that it will be in a current of air, with a wet cloth around the container, which should be moistened from time to time, the evaporation materially lowering the temperature of the container; or it should be kept in the coolest possible part of the house. The milk should be so covered as to protect it at all times from dirt, dust and fly contamination, and mothers are warned to wash their hands carefully before beginning to prepare the milk or food for the baby.

Chairman WELD. Is there any discussion of the address of Doctor Hastings?

Doctor HASTINGS. May I call attention to this chain I have on the wall? This chart, or drawing, represents the different links where contamination can take place in the milk from the cow to the consumer.

Mr. C. L. SMITH (Union Pacific Railway). I have noticed when the lid of a milk can is placed on the can before the milk is cooled entirely, there is a putrid odor present. How can that be remedied?

Doctor HASTINGS. That is a very pertinent question and I am glad to have had it brought up. It demonstrates the extreme importance of chilling the milk as rapidly as possible.

Chairman Weld. The next paper on the program will be presented by Dr. G. H. Hart, at the head of the division of veterinary science, University of California, and the subject is “Health department organization in developing a municipal Pasteurized milk supply with a final bacterial count under 15,000." It affords me great pleasure at this time to introduce to you Doctor Hart, of the University of California. [Applause.]

HEALTH DEPARTMENT ORGANIZATION IN DEVELOPING A MUNICIPAL PASTEURIZED MILK SUPPLY WITH A FINAL BACTERIAL COUNT UNDER 15,000.

GEORGE H. HART, D. V. M., M. D., associate professor of veterinary science,

College of Agriculture, University of California, Berkeley, Calif.

SCOPE OF THE WORK.

The problem confronting a municipality of the first class in developing a high-quality milk supply still remains a task of major responsibility and difficulty, despite the great aids given in recent years by scientific discovery in both knowledge and technique. The milk shed of a great city covers a wide range of territory and a great many farms. The constant flow of the daily supply from these diverging points, hundreds of miles in extent, through comparatively few central plants, and out again by way of wagons, stores, restaurants, and the home kitchen, to the consumer, is a journey constantly fraught with danger as to quality, and possible disease transmission. I think it is no longer open to argument that all of the milk can not be of the same quality, and, therefore, a grading system is essential to-day in any comprehensive attempt at supervision.

These are matters covering the sanitary side of inspection, and while this is a very big problem, the health of the animal side is one almost, if not equally, as large. Enough thought has not been given to these two factors, both of which are essential to a full appreciation of the work. In too many parts of the world stress has been laid on only one of these phases to the exclusion of the other, and never will the problem be fully settled until both are properly handled. Where the health of the cow has been considered of paramount importance, Utopia in this regard has been far from reached; and where sanitation has been the goal, while progress has certainly been made, the health of the cow has largely been held in the background. These two phases of the question are quite different, with widely varying methods of approach, but nevertheless the time has come when both should receive consideration for a full understanding of the subject.

The increasing use which milk and dairy products have enjoyed during the last few years as a result of the development of the newer knowledge of nutrition, renders it incumbent upon the dairy interests to appreciate more generally what full public confidence in the quality of the product is really worth in financial return. This confidence can not be obtained until the original source, namely, the producing animal, is placed in a position where her body is sound and the slogan, “Pure milk from healthy cows," is really made to mean something.

In a few places the economic question has been given foremost consideration by municipalities to the extent even of going into the milk business and developing a publicly owned and operated monopoly. An outstanding example of this kind is the city of Wellington, New Zealand, with a population_of_125,000 inhabitants. Under the leadership of Councilor C. J. B. Norwood and Manager Henry A. Ward, this governmental novelty has been in operation for several years and has met with success in reducing the cost of milk distribution. Although the quality of the supply has been improved, bacterial standards have not been used, unless they have been very recently established. The quality of the incoming milk has been determined by the methylene blue reduction test applied at the receiving platform.

Budapest, Hungary, established a very remarkable municipal milk plant about 1893. It handled approximately 50 per cent of the milk supply for the 600,000 inhabitants of the city. The plant was directly supervised by the health officials of Budapest, and maintained a research laboratory. Pasteurized milk was prepared for the feeliing of infants for one day in a series of bottles. This is known as the Saxlet method, after Professor Saxlet of the pediatrics department of the University of Vienna. At the time of its construction and for a number of years thereafter, this plant was considered the most ideal milk-handling establishment in Europe. Naturally the war and conditions following, caused it to suffer greatly, both in efficiency and the extensiveness of its operation.

The rapid development of the United Dairies, in London, called the milk trust, with a capital of $20,000,000 and 10,000 employees, resulted recently in a parliamentary investigation. The published report frees the company from all blame and gives it credit for a vast improvement in the milk business of Great Britain, which until recently has been conducted on such a low level, from both the sanitary and business standpoints, as to be almost a national disgrace.

The work on which this paper is written deals almost entirely with the sanitary side of the market milk problem.

OBJECTS TO BE ATTAINED.

The object of a successfully operated municipal milk inspection system is to make progress toward the ultimate goal. As no large community has yet reached the goal, progress is all we can look for. Too many costly abortive efforts have been made to step at one stride from inferiority to supposed perfection, with the invariable result of little or no progress. We must always realize that the inspecting departments stand between dwellers in urban communities on the one hand, having in too many cases little interest and less knowledge of conditions in the country: On the other hand are the dairy producers in rather large numbers who, above all agriculturists, have an exacting, long-drawn-out daily task to perform 365 days in the year, with a comparatively narrow margin of profit in return for the service rendered. Improvement, although justified and sound from public health and economic reasoning, can not be too suddenly carried out. The financial condition alone may be too great to overcome quickly. Time is required at best to get a large body of people to change from long-established practices and accept new ones.

Many dairy sections are saddled with bad economic practices, including barter in cattle, land leases, feed handling, and so forth, which tend seriously to retard progress. When pressure is applied too rapidly the dairymen, on account of various factors and because they exist in numbers, organize to resist, and when thoroughly aroused, will effectually retard improvement, despite the almost unlimited police power of municipalities. All persons of long experience in the work who have been aggressive in bringing about improvements have seen this power demonstrated. To permit development of such a situation is a serious mistake for which there is each year less and less excuse. For this reason, one object of the work, and one of not the least importance, is cooperation with, and education of, the dairymen along progressive lines. Fortunately, in this country at the present time, in the farm bureau organization, dairy council work, breed associations and dairymen's associations, very potent agencies exist for accomplishing the purpose.

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