GB2358124A

GB2358124A - Method of cleaning and monitoring in ware washing machines

Info

Publication number: GB2358124A
Application number: GB0100709A
Authority: GB
Inventors: David Roy Mitchem
Original assignee: CHEMISPHERE UK Ltd
Current assignee: CHEMISPHERE UK Ltd
Priority date: 2000-01-14
Filing date: 2001-01-10
Publication date: 2001-07-18
Anticipated expiration: 2021-01-10
Also published as: GB2358124B; GB0002444D0; GB0100709D0

Abstract

A method of cleaning adapted to encourage effective cleaning of glasses and dishes using a warewashing machine comprises setting up the operating parameters of the warewashing machine according to specifications and testing the washed product for biological activity on its surface. Washed product is periodically tested thereafter and the operating parameters of the warewashing machine are checked and re-set when unacceptable levels of biological activity are detected. Washing parameters which may be set include water pressure, water hardness, water consumption per cycle, boiler temperature, water tank temperature, detergent quantity and rinse aid quantity. The test preferably involves the use of a reagent which will produce bioluminescence with adenosine triphosphate.

Description

2358124 1 METHOD OF CLEANING The present invention relates to a method of

cleaning and to a method of optimising cleaning. More particularly, it relates to a method of cleaning glasses and dishes using dishwashing or glasswashing machines and to a method of optitnising the cleaning process by checking on and improving the operating parameters of the machine.

Most commercial establishments where glasses or dishes are used, such as public houses, hotels, bars, restaurants, cafes and the like utilise dishwashing or glasswashing machines. For the purposes of convenience, the present invention will be described with reference to its use with a warewashing machine which terms covers all machines for washing glasses, dishes, cutlery, plates, cups, cooking utensils and surfaces and the like.

It is usual for warewashing machines to be installed, usually intended to be set to the manufacturer's specifications, but rarely complying fully therewith. The machines are infrequently aligned to appropriate detergent systems to ensure optimum performance and do

2 not regularly produce clean and sterile ware, which is particularly important for wellperforming glasses, i.e. those which ensure the optimum dispensed product presentation. The machines are then used mercilessly until it becomes obvious that some remedial attention is required. Thus, for a large part of their working lives, such warewashing machines may well be operating below their optimum performance levels. This results in underwashing and glasses which are not perfectly clean.

Cleanliness is very important in glassware used in public houses. A good pint (or other volume) of beer (which term includes lagers and stouts) should have good nucleation, i.e. the points of formation of the bubbles should continue to generate bubbles for as long as possible so that the pint of beer remains sparkling. The pint of beer should have good head retention, this being particularly important in some parts of the country where beer is considered flat unless it has at least an inch of froth. Furthermore, the beer should produce lacing of the glass as it is drunk and the level diminishes. All of these desirable features are promoted when the glass is perfectly clean, and suffer when it is not.

Not only is underwashing a problem, but other washing faults may manifest themselves, particularly in the case of washed glasses, which should be sparklingly clean. Unsightliness, often described as a white or opaque etTect in "cleaned" wares, may be caused by yeast mould, deposits from hard water, a surplus of detergent in the wash, excessive dosage of rinse aid, or a salt deposit from the softener used.

It is an object of the present invention to produce a method of cleaning and for monitoring or operating warewashing machines to rediAce or eliminate such underwashing and other problems, thereby promoting optimum or improved washing.

3 According to a first aspect of the present invention, there is provided a method of cleaning which comprises checking at least some of the operating parameters of a warewashing machine, setting each of said parameters to an optimum level, carrying out a wash and testing the washed product to determine a level of biological activity on its surface.

Preferably the at least some operating parameters are selected from water pressure; water hardness, water consumption per wash cycle-, b-oiler temperature; water tank temperature, detergent quantity and rinse additive quantity.

The product may be tested to access the bioluminescence produced when a sample is reacted with a predetermined reagent.

Said predetermined reagent may be a reagent adapted to give off light on reaction with adenosine triphosphate.

The bioluminescence may be measured with a luminometer.

Optionally, the individual steps comprising the method of cleaning may be performed separately and/or non-consecutively.

According to a second aspect of the present invention, there is provided a method of cleaning which comprises the steps of testing recently washed product from a warewashing machine to determine a level of biological activity on its surface, in response to the results of said 4 testing, determining appropriate remedial actions to be taken with respect to the warewashing machine, and causing said remedial actions to be carried out.

Preferably, said remedial actions comprise checking at least some of the operating parameters of the warewashing machine and setting each of said at least some of the operating parameters to an optimum level.

The at least some operating parameters may be water pressure; water hardness, water consumption per wash cyclel boiler temperature-, water tank temperature, detergent quantity and/or rinse additive quantity.

Advantageously, said remedial actions further comprise subsequently carrying out a wash and testing product from said wash to determine a level of biological activity on its surface.

Optionally, said remedial actions may comprise testing other possible sources of biological contamination.

Said other possible sources may comprise storage surfaces for clean wares awaiting use and interior surfaces of the warewashing machine.

Preferably, said testing step comprises assessing the bioluminescence produced when a sample taken from the surface of said product is reacted with a predetermined reagent.

The bioluminescence may be measured with a luminometer.

As is known, commercial glasswashing machines are required to clean batches of glasses very rapidly so that they may be returned to use. As stated above, it is important for optimum delivery of the beer or other drink, that the glass is as clean as possible. To this end, there are seven fairly critical parameters of the wash, the machine, and the water and materials used during the wash, which are:

Water pressure; Water hardness, Water consumption per wash cyclel Boiler temperature; Water tank temperature, Detergent quantity; and Rinse additive dosage.

(The above assumes that the quality of the detergent and rinse additive is appropriate).

Hence, in order to optimise the performance of warewashing machines, a hygiene operative must first check that the water pressure, water hardness, water consumption, boiler temperature and water tank temperature are all in accordance with the warewashing machine manufacturers specification. If they are not, they must be so set. Then, and only then, can detergent and rinse additive be added and a wash performed.

6 One or more of the cleaned wares or glasses are then swabbed and the swab is contacted with a reagent adapted to give off light on reaction with adenosine triphosphate (ATP) which is present in all bacteria, yeast and mould cells and is indicative of their activity. The more ATP is present, the more light is produced by the reaction. A luminometer can then measure the amount of bioluminescence and hence the degree of contamination present in the sample- One advantage of this system is that a luminometer may be made sufficiently robust and reliable to be taken to the warewashing machine to provide an instant readout of its cleanliness or efficiency. If the warewashing machine results are high, even after the checks have been performed, then a fault is present and remedial action must be taken.

The microbial pollution of other sources may be checked at the same time. Obvious candidates are:

Storage surfaces for the clean glasses or wares awaiting use; the interior of the warewashing machine, and 11 clean" wares or glasses after storage but prior to use.

The hygiene inspector/technician would ideally revisit the warewashing machine at regular intervals of say, six months. At such a later visit, it is preferred first to test the microbial contamination level and only check and reset the parameters if the level is higher than acceptable.

Clearly, it is possible for the testing step or steps to be performed by a first person and the checking and'adjustment of operating parameters of the warewashing machine to be carried 7 out by a second person. For example, said first person and said second person might only be trained to carry out the corresponding steps of the process.

Alternatively, either one or both of said first person and said second person might be providing the corresponding steps as a service for the user of the warewashing machine.

Claims

I A method of cleaning which comprises checking at least some of the operating parameters of a warewashing machine, setting each of said parameters to an optimum level, carrying out a wash and testing the washed product to determine a level of biological activity on its surface.
2. A method of cleaning as claimed in claim 1, wherein the at least some operating parameters are selected from water pressure-, water hardnessIwater consumption per wash cycle; boiler temperature; water tank temperature; detergent quantity and rinse additive quantity.
3. A method of cleaning as claimed in either claim I or claim 2, wherein the product is tested to assess the bioluminescence produced when a sample is reacted VAth a predetermined reagent.
4. A method of cleaning as claimed in claim 33, wherein said predetermined reagent is a reagent adapted to give off light on reaction with adenosine triphosphate.
5. A method of cleaning as claimed in either claim 3 or claim 4, wherein the bioluminescence is measured with a luminometer.
6. A method of cleaning as claimed in any one of the preceding claims, wherein the individual steps comprising the method are performed non-consecutively and/or separately.

9
7. A method of cleaning comprising the steps of testing recently washed product from a warewashing machine to determine a level of biological activity on its surface, in response to the results of said testing step, recommending appropriate remedial actions to be taken with respect to the warewashing machine and causing said remedial actions to be carried out.
8. A method of cleaning as claimed in claim 7, wherein said remedial actions comprise checking at least some of the operating parameters of the warewashing machine and setting each of said operating parameters to an optimum level.
9. A method of cleaning as claimed in claim 8, wherein said remedial actions comprise subsequently carrying out a wash and testing the product from said wash to determine a level of biological activity on its surface.
10. A method of cleaning as claimed in either claim 7 to 9, wherein said at least some operating parameters may be selected from water press ure, water hardness, water consumption per wash cycle, boiler temperature, water tank temperature, detergent quantity and rinse additive quantity.
11. A method of cleaning as claimed in any one of claims 7 to 10, wherein said remedial actions comprise testing other possible sources of microbial contamination.
12. A method of cleaning as claimed in claim 11, wherein said other possible sources comprise storage surfaces for clean wares awaiting use.
13. A method of cleaning as claimed in either claim I I or claim 12, wherein said other possible sources comprise interior surfaces of the warewashing machine.
14. A method of cleaning as claimed in any one of claims 7 to 13, wherein said testing step comprises assessing the bioluminescence produced when a sample taken from the surface of said product is reacted with a predetermined reagent.
A method of cleaning as claimed in claim 14, wherein said predetermined reagent is a reagent adapted to give off light on reaction with adenosine triphosphate.
16. A method of cleaning as claimed in either claim 14 or claim 15, wherein the bioluminescence is measured with a luminometer.
17. A method of cleaning as claimed in any one of claims 7 to 16, wherein the individual steps comprising the method of cleaning are performed non-consecutively and/or separately.