The last thirty years have seen many interesting developments in kitchen machinery. In the kitchen as in other fields of production where operations are carried out manually, increased output demands mechanization to speed up the process and reduce labor. In the domestic kitchen all operations can be performed easily by hand, and the housewife herself prepares and cooks the various items which constitute a meal. In a large kitchen, on the other hand, each section of the work is performed by a different person or group of persons, and each individual has therefore a greater proportion of routine work. The need to minimize the monotony of this routine provides the major incentive for thinking out ways of doing the work with as little manual labor as possible, while ingenuity is further encouraged by the saving of time and physical effort which can be effected, with a consequent reduction in staff and production costs and avoidance of fatigue. Moreover, the performance of a machine can be closely controlled and is not subject to human variations, so that it is much easier to obtain uniformity of production over a period of time.
Although some of the machines used in large kitchens are manually operated, the majority of them are power driven. The electric motor is the usual source of power and it is clearly this extremely useful device, made available through large-scale production, which has contributed to the increase in the number and variety of machines found in the modern kitchen. In many of the machines only a comparatively small amount of power is required and fractional horse-power motors are adequate. Only for the larger pieces of equipment such as the bigger dish-washers and mixing machines, are motors of more than two or three horsepower required.
General Points in considering choice
The caterer who is faced with the choice from among many items of labor-saving equipment must consider various questions related to their use, and the first is usually that of cost. The initial cost of the machine itself, the cost of installation, the depreciation and actual running costs in current consumed must be ascertained and compared with the reduction in staff wages which would result from the employment of the equipment. But cost may not be the only factor that is relevant to staff problems; the installation of labor-saving machinery if often essential because of the difficulty in obtaining staff to perform particular operations.
The next point to consider is the mechanical performance of the machine as described by the manufacturer, and particularly the comparison between the nature of the final product from the machine and that resulting from the same operation carried out by hand. Little difficulty is likely to be experienced with well-known equipment from reputable manufacturers but recent inventions which have not stood the test of time may need to be more carefully examined before purchase to ensure that they will in fact perform the function for which they are required.
Another important point to consider is the design of the equipment from the point of view both of efficient operation and of easy cleaning. It is essential for both reasons that the design should be simple. In the kitchen as in other spheres the introduction of machines sometimes meets with opposition from conservative employees. There is a tendency to continue to do the job in the same way in which it has always been done and the introduction of a complicated piece of machinery is not always welcomed. It is important therefore in the first place that the machine should be as simple and foolproof as possible in operation. That it should also be designed for easy cleaning seems obvious, yet it is often overlooked by the makers. Not only should the operation of the machine be simple but it should also be designed and installed so that it can be operated with the minimum effort and thought. The position of the controls, the height of the vessel to be loaded, the amount of lifting, reaching and stretching involved, every part of the operation must be investigated to ascertain whether they are satisfactory and make for comfortable and smooth working.
Vegetable Paring Machines
These machines, which are known by various names such as vegetable peelers, vegetable cleaners and potato peelers, are designed to clean and remove the peel from some types of root vegetables, particularly potatoes and carrots. The essential part of the operation consists in bringing the vegetables into contact with a rough surface which rubs off the peel. This is done by having a fixed container, usually called the hopper or paring chamber lined with carborundum and provided with a base disc surfaced with the same material; this disc rotates at moderate speed and in so doing throws the potatoes against the rough surfaces and removes the peel. In order to increase the efficiency of the operation the disc usually has an undulating surface. To facilitate the removal of dirt and scrapings the hopper is provided with a cold water supply so that a spray of water can play on the surfaces of the vegetables during the operation. The mechanical part of the equipment is concerned with the rotation of the base disc; the power for this operation may be supplied manually or by an electric motor, but it is obviously only possible to use the former method when small loads of not more than about 10lb are expected. It will be noted that the machine has in addition a water-tight door on the side of the paring chamber with a chute to facilitate the removal of the vegetables when cleaned and an interceptor which holds back the peelings and allows the waste water to filter through to the main drainage system.
The operation of the machine is simple but attention to various points of detail will contribute towards its efficiency. Vegetables when purchased in sacks are mixed with soil and sometimes also with stones which, if not removed, will cause excessive wear on the carborundum plates. It is of course advisable to guard against this by purchasing potatoes from reputable dealers but if by chance some stones are present in the sack, they should be removed before the machine is charged. Another point to watch is that the machine is running at full speed before the vegetables are put in, for, unless this is done, there is a risk of overloading the motor and causing a breakdown. The time the vegetables are left in the machine should not be longer than is required to remove all the dirt and the greater part of the skin; all the skin cannot be removed without excessive waste and the lower parts of the hollows in the surface of the vegetable must be peeled and the eyes removed subsequently by hand. The correct time to leave the potatoes in the machine varies somewhat according to the design of the machine, the amount of wear to which the carborundum plates have been subjected and the condition of the potato, but it is usually about 5 minutes. If this time is exceeded, not only will there be waste of current and material and excessive wear on the carborundum and machinery, but the disposal of waste will also be more difficult owing to the presence of starch in the sludge. When once the skin has been removed continued friction rubs away the white substance underneath, which creates foam in the interceptor, delays filtering, and calls for more frequent emptying of the peel trap to prevent flooding.
When the potatoes have been in the machine for the required time the door of the hopper is opened and the potatoes shot out into a suitable container. This may be either an adjoining sink which will then be used for the eyeing process, a metal container on wheels, or a bucket in cases where the eyeing process is to be undertaken at some distance from the machine. On many models the hopper is adjustable to allow for alternative positions of the chute so that it can be fixed in the kitchen to suit whatever method of disposal is adopted.
Vegetable paring machines may be either table or pedestal models, but in both types the height of the hopper should be convenient for loading. In some large kitchens potatoes are stored at a level above that of the machine and by means of a special device can be admitted to the machine as required. In such cases the height of the hopper is not important, but usually machines are loaded by hand and it is therefore essential that the height of the top of the hopper should be the minimum compatible with the arrangements made for the discharge of the potatoes after cleaning. The height of the average pedestal model even in the largest sizes is not more than 16″ with a chute 25″ above the floor. This is not an unreasonable height for loading but if it is intended to use the machine in conjunction with an adjoining sink the height of the top of the sink must be less than 25″, which of course is low for normal use. If, however, the machine is fixed on a stand to bring the height of the top of the chute up to a level to discharge into a sink at the normal height of 36″, the height of the top of the hopper must be little short of 5′, which is too high for the normal person to lift a heavy load. Bench models are about 25″ in height and will present similar loading difficulties if they are fixed on a bench 36″ high.
After the potatoes have been discharged into a sink the eyes must be removed by hand. In front of the sink two or three persons can work to eye the potatoes which are then dropped into the trough at the back from which they roll into mobile sink places nearby.
These machines are made in sizes rated according to the weight of potatoes they can take at one charge and the sizes normally found in kitchens are 71b., 141b., 28lb., and 56 lb. The electric motors used to operate them range from ⅛ h.p. to 1 h.p.
Some mention has already been made of the interceptor, or, as it is sometimes called, the sludge tank. In the model shown in the cut-away view this forms part of the pedestal and gives a compact design. In many models it is a separate item, fixed usually alongside the machine, but sometimes at some distance away in a shallow inspection chamber in the yard. But wherever it is situated it cannot be too strongly emphasized that the interceptor requires frequent emptying and cleaning. If due care is not paid to this, the peelings will ferment and cause insanitary conditions. Although the general practice is to remove the sludge by means of an interceptor before the liquid is allowed to enter the main drain, in some installations an interceptor is not used and the discharge goes direct to the drainage system, carrying the sludge with it. This is obviously good from the caterer’s point of view since it reduces labor, but it is not always permitted by the Local Authority.
Cleaning and maintenance of these machines is simple but requires regular attention. The paring chamber should always be washed down carefully after use. Care should be taken to see that no waste matter remains under the base plate, which in the majority of designs can be easily removed for cleaning. It is also important that all moving parts of the machinery be adequately lubricated; requirements vary from one model to another and it is important that the maker’s instructions should be studied and their recommendations carried out.
These machines are designed to deal with any mixing and beating work undertaken in the kitchen and are consequently invaluable to the caterer since they save energy and time. Even if the actual process is not completed more quickly by machine than by hand, the cook is free while the machine is in action to do other jobs such as preparing the necessary materials.
The mixing machine consists of a deep bowl (usually of metal) into which the material to be mixed or beaten is placed. The bowl is fixed to the main frame of the machine from which it can be detached and the mixing beater or whisk rotates inside the bowl on a vertical spindle driven by an electric motor. In a mixing machine of this kind the rotation must be eccentric to the center line of the container so as to avoid carrying the whole mass of material round and round without the relative movement of the different components that is necessary for proper mixing. A further feature of the mechanism, introduced to ensure that no part of the mix is left undisturbed, is the rotation of the axis of the moving spindle about a secondary axis concentric with the mixing bowl and so arranged that the edge of the beater wipes to within a small fraction of an inch the whole of the surface of the container at different points in turn all round the circle. This planetary action is adopted in almost all modern mixers.
It is obvious that different speeds of rotation are needed for different substances. The high speed which is required to whisk a liquid such as egg or cream would if used for rubbing fat into four cause part of the four to be thrown out. Three speeds are usually provided by means of a suitable gearbox embodied in the head of the machine; the design varies between one maker and another. In some cases the speed changeover involves the shutting down of the machine and the adjustment of the lever to the new position while the machine is at rest, whereas in others the speed can be raised or lowered by constant mesh gears without declutching or stopping the motor. The number of revolutions per minute of which the machine is capable varies from one maker to another and the following figures are for well-known makes of machine.
These actual running speeds are only very slightly affected by the load placed on the machine.
The main use of this machine is for mixing and whisking and it is provided with three separate attachments, to suit the different types of work it is required to do. A hook is provided for dough work and for rubbing fat into flour, for which the slowest speed is employed. The beater is generally used on the second speed for creaming butter and sugar and for mashing and beating potatoes. The whisk is also used on this speed in the first place to thicken the mixture, and then put on to top speed when the danger of splashing has passed. In addition to this main work the motor of the machine, by the use of particular attachments, may be harnessed to do other work such as mincing, shredding of vegetables and sieving.
Mixing machines are made in various sizes which are rated according to the capacity of the bowls. The size is often given in American Quarts (one American Quart equals 4/5ths English Quart). The sizes available in American Quarts range from 10 quarts up to 80 quarts and the motors range from 1/3 h.p. for a 10 quarts model, to 1 h.p. for a 40 to 50 quarts model and 2 h.p. for an 80 quarts model. Some models are available with an adapter so that a smaller sized bowl can be run on the same machine and used when the larger bowl is too big for a particular mixing. With all models it is possible to obtain more than one bowl for use on one and the same machine; this enables one bowl to be on the machine while the other is emptied, washed and refilled, and so allows the machine to be run almost continuously.
With the larger sizes it is possible to obtain a small 3 or 4-wheeled dolly truck designed to fit the bowl, which can be lowered into it and wheeled away for attention in another part of the kitchen. This is particularly useful where more than one bowl is used and when the bowl and its contents are so heavy as to make lifting difficult. Another useful device produced by one manufacturer is a special outer bowl into which the mixing bowl will fit. This outer bowl can then be packed with a freezing mixture thereby converting the machine into an ice cream maker.
When purchasing a machine the caterer will find it useful to know the amount of food which can be conveniently handled in the various sizes. Owing to the variety of the ingredients used it is not possible to give here the amounts for all types of mixings; the weight of flour for a mixing of short pastry is therefore given as a guide. The 10 qt. American machine will take 4 lbs. of flour, and the larger machines amounts in proportion. An extension rim is available with many models which increases the normal amount handled, particularly with dry mixings where flour may fly.
Mixers are made in both bench and pedestal models, the former being more general for the smaller sizes and the latter for the sizes from 30 qts. upwards. There is also one model available in the small sizes with a wall fixing, which is obviously useful under some restricted conditions.
These machines can be relied on to do all the work for which they are designed as well as it could be done by hand. In fact, where the operation requires considerable power, as in the creaming of fat and sugar, the specific gravity of the resulting mixture is considerably lower than can be obtained by the average person by hand, thus showing that the operation is done more efficiently by machine.
Mixing machines are comparatively simple in operation and can be used easily by the majority of kitchen staff, although it is perhaps as well to emphasize the importance of securing the bowl firmly by ensuring that the manufacturers’ safety precautions for this are observed. The actual methods used vary. In one type holes on each side of the bowl fit over pins on the holder of the machine and the lug at the back of the bowl engages with the spring socket in the middle of the holder. This correct securing of the bowl is necessary to ensure proper centering of it, otherwise the mixer blades will rub the sides of the bowl and worn metal will be mixed with the food. If this is occurring it can usually be detected by a discoloration of the food. This rubbing can also result from denting of the bowl through careless handling, and care should therefore be taken to avoid mishandling in this way.
Two other matters require emphasis when instructing kitchen staff in the use of electric mixing machines. The first is related to the care of the machine. To ensure that the motor is not over-strained it is essential to switch it on before raising the bowl and bringing the contents into contact with the rotating beater. The second relates to the safety of the operator. When a machine is switched off the beaters continue to rotate for a short time. This is more noticeable in large than in small machines because of the weight of the beater head. It is therefore essential that the operator waits until the arm ceases to rotate before attempting to remove the beater head. Broken fingers and badly bruised hands can result if this instruction is not obeyed.
One other point deserves mention. Because of the ease with which a mixer works there is the danger that foods may be overmixed, in some cases affecting the required texture of the product. For example, if in rubbing fat into flour for short pastry the mixing is continued for too long a period, the fat and flour will bind together and form a mass which will take up very little water for complete binding and the pastry when cooked will not be of the correct texture. Another example occurs in mixing the flour into either a creamed butter and sugar mixture or a beaten egg and sugar mixture for a sponge. The amount of mixing in both cases should be the minimum necessary to obtain a homogeneous mixture and if more is given not only will the sponge be of a too tough texture than required but the maximum volume will not be obtained.
Its a vertical cutter mixer, another type of machine which has been recently developed for use not only in cutting meat, fruit and vegetables but also for mixing and blending pastry and bread, etc., and for emulsifying oil to make mayonnaise. The blades rotate at high speed and because of this many operations can be carried out in less than one minute.
Much thought has been put into the design of machines for reducing the work involved in cleaning dishes and cutlery. A number of different types are available, ranging from those in which the process is almost completely automatic, the only manual work involved being that of loading and unloading the trays before and after insertion in the machine, to those in which a considerable amount of handling is required but some mechanical help is supplied by the equipment.
There are four processes in washing up, namely, preliminary clearing or stripping, washing, rinsing and drying. The first of these is not always necessary, but when it is, it is done by hand. The third and fourth processes are interconnected. The usual method is to rinse at 180°F. to 190°F. and in so doing heat the dishes to a temperature sufficient to promote quick drying without the aid of cloths. It is in the method adopted for washing the articles that variations occur. Various types of soiling are commonly found on dishes, but they may be divided into three main groups, namely the soil which is soluble in water and can therefore be removed easily by immersion in hot water, the soil which can be removed by hot water containing a suitable detergent, and the soil which can only be removed by friction. The latter category is the one which provides most scope for invention and three different methods are used in the washing up machines available in this country.
In one type articles are placed in racks in a vessel in which water is agitated by a motor driven impeller, and the turbulent water so produced provides the friction or scrubbing action to remove the soil from the articles. In another type two cylindrical brushes are fixed to the side of a sink and partially below the surface of the water. These brushes rotate at high speed on parallel axes so that the tips of the brushes just touch and remove the soil from an article placed between them. In the third type the soil is removed by the scrubbing action of high pressure hot water sprays.
In the first two methods a certain amount of manual work is required to insert and remove the racks in the turbulent immersion type, and to place the article between the brushes in the rotating brush type, but when the third method is used it is possible for the process to be completely automatic. The dishes are put into racks at one end of the machine through which they progress on a moving band, the processes of washing and rinsing being carried out in the successive parts through which the racks move.
When the methods adopted employ either turbulent water or brushes one sink is used for the washing process, and an adjacent sink for the rinsing process. This rinsing sink is heated either by an electric element or by gas burners and the water in it should be maintained at a temperature of 180°F. to 190°F. The temperature of the water is an important part of the process for not only does it ensure the thorough heating of the articles, thus promoting quick drying, but it also virtually sterilizes them.
Mention should be made of an arrangement which although not employed as a dishwasher in the accepted sense of the word because no mechanical aid is employed, is a useful, efficient and comparatively inexpensive substitute. Two adjacent sinks are used, one for washing and the other, heated by gas or electricity, for rinsing. Apart from the fact that the articles must be washed by hand before being placed in the specially designed racks for subsequent immersion in the rinsing sink the process is as described for the turbulent immersion or brush type of dishwasher. A great deal of labor is saved by this method since it obviates drying many of the articles by hand.
The machines which make use of the scrubbing action of high pressure hot water jets are variously known as automatic or semiautomatic, spray, flight or push-through type. They have no resemblance whatever to a sink and from the outside appear as a large rectangular box with an opening at each end over which a splash curtain hangs.
In this type the articles, after being placed in rectangular trays, are washed by sprays which play on them from above and below. When washed they move on automatically to a second chamber where rinsing is carried out, also by sprays directed from above and below. In this particular type the articles are subjected to yet a third series of jets which are known as the Sterilizer Sprays and eject water at a much higher temperature, usually about 180 F.
The flight type is a recent development which can be operated without the use of trays. This machine is constructed with a continuous peg type conveyor belt into which trays carrying cups and cutlery, etc., can be loaded, or alternatively plates and trays, etc., can be slotted in between the pegs. The belt is designed so that after passing through the loading; washing, rinsing and unloading sections it turns over and returns underneath the washing chamber to the loading section. At least one operator is needed w with end and in peak periods many more are required. These machines, which are made in various sizes, some of them being up to 30ft. in length, require a large dish room to accommodate them and the parking space needed at both ends for used and clean dishes. Partly to solve the problem of space and partly to make the machine operable by a smaller number of employees in off-peak periods the rotary, merry-go-round or rackamatic machine has been devised. In this model the conveyor belt does not turn over but after passing through the washing chamber turns through 180° and returns along the outside of the chamber, thus giving a considerable increase in the loading and unloading area.
The amount of tabling needed at each end of the machine will vary according to conditions, but it should be adequate on the intake side to hold a large number of articles awaiting treatment and on the delivery side to accommodate all the racks which must be parked there while drying. On the intake side it is usual also to extend the tabling to include provision for stripping. One method sometimes adopted is to have a circular chute in the middle of the bench through which waste material from plates can be delivered direct into a bin placed beneath. With the sink type of dishwasher the tabling usually takes the form of draining boards set so that water from the racks can run back into the sink.
The capacity of a machine is rated on the number of articles handled in one hour and models are available which will deal with anything from 1,000 per hour to 10,000 per hour. It must be realized, however, that this figure relates to a mixed group of articles and not usually one type only; the proportion of picces for capacity ratings are 1 cup, 1 saucer, 2 plates 2″ diameter, 1 knife, 1 fork, 2 spoons. It is usual to consider ten as the average number of pieces per person, and therefore it is generally stated that a machine which is rated at 1,000 pieces per hour is suitable for the crockery of 100 persons. But clearly this is only an average figure since the number of pieces used by an individual must vary considerably with the type of meal taken. The time available for washing up is another important factor which affects the size of machine required for a given number of persons; if the operation can be spread over a period exceeding one hour a smaller machine can be considered.
In hard water districts furring up of the washing up equipment may become a serious problem. Over a period of time thorough cleaning of the rinsing sink becomes difficult, and although formation of the deposit is slower where the material used for the sink is stainless steel, even in this type the nuisance occurs in time. The Spray type of washing up machine suffers from the same disadvantage and in hard water districts, unless other precautions are taken, de-scaling must be carried out periodically. The only satisfactory remedy, however, is to use soft water obtained by one of the well known base exchange softeners.
Pot and Pan Washer:
Machines are now available similar in design to the semiautomatic spray type dishwasher which have been specially designed for washing pots and pans and will accommodate the large ones used in food service work. These vary in efficiency but at least one manufacturer in the U.S.A. has produced a model which is satisfactory.
Another method used fairly generally in the U.S.A. is the three-sink system, namely soak, wash, rinse and sterilize with at least one heated sink. If these are used in conjunction with a high pressure hand operated spray good results can be obtained.
As already mentioned it is possible to perform the operation of mincing by inserting a special attachment into the mixing machine head. This is quite satisfactory where mincing is done only infrequently, but where the mixer is in use almost constantly for its real purpose it may be advisable to have a separate mincing machine. The operation of the machine is identical with that of the hand operated model, the only difference being that the power is supplied by a small electric motor leaving the operator free to feed the machine. These machines are made in various sizes rated according to the weight of food which will pass through the plate in one minute or one hour.
The slicing of meat and the cutting of bread are operations which when performed manually not only require considerable skill but also take time. A machine for these operations is therefore a valuable asset to the caterer. In the usual design a feed tray holds the food to be sliced firmly against a circular cutting knife. It will be realized that power is required both to rotate the knife and to advance the food against the blade. Models vary in the amount of mechanization for these operations. In one type, an electric motor is used to spin the knife and the traversing of the food past it is performed manually. In another construction both operations are automatic, power being supplied by a fly-wheel shaft which is manually controlled, or in yet a further type both operations are motor driven. A model with a fixed knife is also available, but is, in all other respects, similar to the first type described.
An interesting development of recent years is the production of a machine which will both cut and butter bread. The machine is completely automatic and the butter, in the form of a softened lump held in a special container, is applied to the loaf before each slice is cut.
Care must be taken in all these slicing machines to ensure that the blade is kept sharp and rust free. Models are usually supplied with a carborundum sharpening attachment which can be placed in contact with the blade as it is turned through several revolutions. If this sharpener is used regularly the edge of the blade should always be in good condition. Careful drying after use is the best preventive of rust, and a little grease on the cutting edge is desirable when the machine is out of use for a few days.
There is one other point which requires care. If material is sliced which contains hard pieces such as bone the blade may be damaged, and it is therefore important to remove all bone from food to be put through the machine.
Machines are made in various sizes according to the size of the cut and the thickness. Cuts of the following dimensions — 10″ x 71″, 13″ x 71″ and 16″ x 71 are available in slice thicknesses ranging from wafer up to ⅝”.
Vegetable Shredding Machines:
Various types of machine are available for cutting up vegetables. Some are intended for one operation only such as making potato chips, or cutting beans, while others can be used for a variety of operations by the insertion of the different cutting discs provided. The work done includes shredding, slicing, grating, cutting straws and chips, and the making of breadcrumbs. The value of this machine to the caterer is considerable for not only does it save time and energy but it also gives a more uniform product than can generally be expected by hand. One use of these machines which is not always appreciated is the shredding of cabbage and green vegetables before cooking. This saves the labor of chopping after cooking and also shortens the cooking period so that less vitamin C is lost.
Fresh Cream Air Whip:
This machine consists of a motor driven compressor and a light weight agitator. The process of whipping consists of forcing air from the compressor through fine nozzles into the cream which is turned at a slow speed by the agitator. In this way the cream is aerated and increases in volume by 150% or more. The capacity of the model in plate is 2 quarts of cream yielding 71 quarts after whipping.
This machine which can be either power driven or hand operated is somewhat like a laundry wringer except that there is only one roller. The dough is moved through the machine by the pressure of the roller on a metal plate, both of which are made of stainless steel. The pressure can be adjusted to give different thicknesses, it usually being necessary to put the dough through the machine several times to obtain a thin rolling.
Waste Disposal Unit:
The waste disposal unit or garburator is designed to pulverize kitchen waste so that it can be carried away in a stream of water by the main drainage system. It consists basically of steel knives rotating at high speed within a metal tube attached to a hopper into which the material for disposal is fed. The efficiency of the machine depends on the quality of the steel knives and on the power of the electric motor which drives the blades. For kitchens with a large amount of garbage, motors of up to 7 h.p. rating are available, but for average amounts a motor of 2-3 h.p. is usually found to be adequate.
Equipment for floor scrubbing is clearly a very useful laborsaving apparatus for the caterer, particularly in kitchens where large floor areas must be scrubbed daily. In a small kitchen the machine would be difficult to operate and the high cost of purchase could scarcely be justified, but in a large kitchen it has become an essential part of the labor-saving equipment.
Two separate machines are used for the operation. The first employs a circular rotating brush and a feed tank containing a suitable detergent for scrubbing the floor, the second is a powerful squeegee which subsequently collects the dirty water leaving the floor practically dry.
Automatic machines for dispensing drinks have been widely used in the U.S.A. for several yours and have recently reached this country. A model which content canteen should prove useful in establishments with staffing problems and particularly in providing hot drinks when the canteen is not open.
The machines are made to provide 500 cups of coffee from coffee powder, sugar, and full-cot dried milk stored in containers in the machine, kept free from damp by an electric dryer, When a coin is inserted a cardboard cup is released to which coffee, sugar and milk is subsequently added in amounts controlled by the operator. The cup is then filled with boiling water from a 6-gallon electrically heated tank, the pressure of the water from the tap being sufficient to stir-up and thoroughly mix the powdered ingredients. As the ingredients are not handle at any stage of the proceedings and a new cup is supplied for each drink, the highest possible standards of hygiene are assured.
The machine can be hired or purchased outright, or the operating company will install and maintain it at their own cost and pay a commission on sales to the site owner.
The use of vending machines has been considerably extended to include the sale of different types of food and drink. In some of the universities in the U.S.A., rooms have been specially planned with a complete wall of vending machines which can be loaded outside the room. Some of the machines are refrigerated to maintain food in good condition and are used in connection with a microwave oven for the service of hot food.