DK3293249T3

DK3293249T3 - HOT DRINK MACHINE CLEANER

Info

Publication number: DK3293249T3
Application number: DK16187752.7T
Authority: DK
Inventors: Marion Zwingenberger; Petra Reessing
Original assignee: Chemische Fabrik Dr Weigert Gmbh & Co Kg
Priority date: 2016-09-08
Filing date: 2016-09-08
Publication date: 2019-04-23
Also published as: PL3293249T3; EP3293249B1; CY1121441T1; PT3293249T; EA201791787A1; HUE042276T2; SI3293249T1; LT3293249T; HRP20190599T1; ES2718723T3; EP3293249A1; EA034069B1

Description

CLEANER FOR HOT BEVERAGES MACHINES

This invention relates to a cleaner formulated in solid form for hot beverage machines.

Hot beverage machines for the workplace or home become contaminated from various sources during operation. The water used for operation usually contains lime and other minerals, which form unwanted deposits especially on account of hot operation. Coffee and tea can likewise form unwanted stubborn residues.

Many hot beverage machines can additionally produce milk preparations, like for example milk foam, and mix this into the hot beverages. Then firstly milkstone can form and secondly unwanted microorganisms tend to colonise especially the milk conduits of such hot beverage machines. EP 2 924 101 Al discloses a liquid, mildly alkaline cleaner for dishwashers.

The underlying object of the invention is to make available a cleaner for hot beverage machines of the aforementioned type, which allows easy and universal use and is also environment-friendly and easy to handle.

The invention achieves this object by means of a cleaner formulated in solid form for hot beverage machines, which contains: a) at least one chelating agent for Ca and/or Mg ions selected from the group consisting of MGDA and GLDA, b) at least one complexing agent selected from the group consisting of gluconic acids, iminodisuccinate, ATMP (aminotrismethylenephosphonic acid), DTMP (diethylenetriamine pentamethylenephosphonic acid), HEDP (1-hydroxyethane 1,1-diphosphonic acid), HDTMP (hexamethylenediaminetetramethylenephosphonic acid), PBTC (phosphonobutane-l,2,4-tricarboxylic acid), phosphonic acids; and salts of the aforementioned acids, c) at least one polymeric acid selected from the group consisting of polymeric acrylic acids, methacrylic acids, maleic acids, sulphonated polystyrenes and copolymers ofthe aforementioned acids, the cleaner being free of surfactants, silicates and phosphates, and the cleaner having a pH value of 8 to 11 in 1% by weight aqueous solution.

To begin with, a few terms used within the context of the invention will be explained.

The cleaner according to the invention is formulated in solid form. This comprises in particular a formulation as powder, granules or in compacted form, like for example tablet.

The cleaner is provided to clean hot beverage machines. These are machines, which prepare hot drinks, such as in particular coffee, tea, cocoa or milk drinks, with heated water (either from a storage tank or from a pipe connection) and further ingredients. In particular these can be hot beverage machines containing so-called milk conduits, in which milk is thus formed and processed as component of the hot beverage, for example in the form of milk foam.

Chelating agents can form chelate complexes in particular with Ca and/or Mg ions by way of suitable ligands and thus mask said ions. The chelating agent used according to the invention in accordance with feature a) is different from the complexing agents in accordance with feature b). According to the invention the chelating agents are selected from the group consisting of MGDA (methyl glycine diacetic acid) and GLDA. MGDA and GLDA are also preferred, because they have no toxicity. MGDA is particularly preferred.

The cleaner contains further at least one complexing agent according to the definition in feature b) and also at least one polymeric acid according to the definition in feature c).

The cleaner according to the invention is free of surfactants, silicates and phosphates. This means, that these substances are not added as formulation components and are contained at most on a small scale as contaminants. Preferably it does not contain any disinfecting agents selected from the group consisting of quaternary ammonium compounds, amines and compounds containing active chlorine.

The invention provides a cleaner, which is equally suitable for all cleaning applications in the area of hot beverage machines, in particular coffee machines. These application areas comprise in particular the cleaning of the coffee conduits (coffee lines and brewing unit) and of the milk conduits (milk lines, foam creation, foam compaction).

The combination according to the invention allows all areas of hot beverage machines to be cleaned effectively with an environment-friendly, mildly alkaline cleaner (containing no phosphates and no surfactants) that is not classified as hazardous material. This was impossible with the prior art.

Apart from a good cleaning performance in the area of the coffee remains and milk remains a dissolving of already formed hardness deposits is also achieved. That is advantageous in particular in respect of milk foam creation using hard water and counteracts the formation of deposits from the milk (milkstone). Additional descaling processes (acid wash) required in the prior art are not required.

The cleaner is free of surfactants and silicates and can therefore be washed out easily and without leaving any residues.

Preferably it does not contain any quaternary ammonium compounds or amines or any active-chlorine compounds, which are difficult to wash out, cause foaming or could give rise to a detrimental effect on taste in the hot beverage machine.

The chelating agents according to feature a) are water hardness (Ca and Mg) complexing agents, which can both prevent precipitation of lime from the water and bring already formed water-insoluble compounds containing calcium and magnesium back into solution. Thus both mineral residues formed by milk remains and lime remains precipitated by substances in water can be brought into solution in the area of the coffee conduits and milk foam production (steam input). Moreover these chelating agents have a good iron- and oil-binding capacity.

Complexing agents according to feature b) likewise bind water hardness (and thus prevent precipitation of lime by substances in the water) and serve additionally to inhibit corrosion.

The polymeric acids according to feature c) assist the prevention of mineral deposits and increase the dirt-carrying capacity through dispersion. They thus likewise prevent lime formation, if hard water is used, and keep particles of dirt in suspension. They thus make a good cleaning performance possible in the area of the milk conduits (keeping particles of dirt and milk in suspension and transporting them away). They improve the suspension stability of oil pigment contaminants and thereby contribute also to the cleaning of the coffee conduits.

The cleaner according to the invention has a pH value of preferably 9 to 11, more preferably 9.5 to 10, in 1% by weight aqueous solution. Despite this milk alkalinity the cleaner has a high effectiveness in relation to lime and comparable deposits, which can frequently only be removed by acid in the prior art.

Preferably the weight proportions of components a) to c) are as follows: - component a) 10 to 40% by weight, preferably 15 to 25% by weight; - component b) 10 to 20% by weight; - component c) 1 to 3% by weight.

The remainder up to 100% by weight is made up of further constituents, fillers, tabletting aids mentioned below or the like.

The molar mass of the polymeric acid (component c)) is preferably 4,000 to 10,000, more preferably 6,000 to 8,000.

According to the invention the cleaner can additionally contain a non-polymeric acid, preferably an organic acid, more preferably citric acid and/or maleic acid. This is used, in order to dissolve the solid matter more effectively, e.g. through reaction with fillers or tabletting aids.

According to the invention the cleaner can additionally contain tabletting aids, if it is to be formulated in defined form, e.g. in the form of a tablet.

According to the invention it is preferable, that the cleaner additionally contains a per compound, preferably a peroxo compound, more preferably a peroxosulphate. These assist the removal of all oxidisable contaminants, e.g. proteins or tannins.

Particularly preferably the content of per compound is less than 3% by weight, preferably 1 to 2.9% by weight. A cleaner with a content of per compound below a threshold value of 3% by weight does not have to be labelled as hazardous material.

In a further particularly preferred variant the cleaner according to the invention does not contain any water-insoluble solids. In the prior art insoluble solids with abrasive action, e.g. silicates or microcrystalline cellulose, are frequently used, in particular to clean the milk conduits. These solids are very difficult to wash out and can contribute to the blocking of lines. The cleaner according to the invention achieves a good cleaning effect even without the addition of such solids. Thus the cleaner according to the invention is preferably soluble in water, without any residues, in the usual concentrations for use. A further subject-matter of the invention is the use of a cleaner according to the invention for the cleaning of hot beverage machines, in particular hot beverage machines for the preparation of coffee, tea and/or cocoa drinks.

In this connection the cleaner can be used according to the invention to clean coffee conduits and milk conduits and also to clean a milk foam compression unit.

The concentration for use of a cleaner according to the invention in aqueous solution is preferably 0.4 to 1.5% by weight, more preferably 0.6 to 1% by weight.

The cleaning times are preferably between 1 and 15 minutes, more preferably between 5 and 8 minutes.

Exemplary embodiments of the invention are described below. The figure shows the result of cleaning tests and comparative tests, which are described below.

Example 1 - example of a formulation

The formulation components stated in Table 1 are mixed together and pressed into tablets. The quantities stated in the table are parts by weight.

Table 1

Example 2 - comparative example

The formulation components stated in Table 2 are mixed together and pressed into tablets. The quantities stated in the table are parts by weight. This is a phosphate-containing comparative formulation.

Example 3 - cleaning tests

Tea contaminants were applied to ceramic test specimens. Aqueous solutions of the formulation according to the invention and of the comparative formulation, each having a concentration of 0.5% by weight, were prepared and heated to 65 °C. The solutions were stirred at 100/min with a magnetic stirrer.

The test specimens were immersed to about two thirds into the solutions for 45 seconds and then removed again. The cleaning performance was examined visually.

Because the exposure of the components to be cleaned to the cleaning solution cannot be ensured immediately in the hot beverage machine, but a certain time buffer is needed, e.g. for filling of the line, it must be ensured, that the cleaner solution still has a sufficiently good effectiveness at the end of the cleaning cycle and at the end of the distribution time as at the start of the cleaning cycle.

The described cleaning tests were therefore carried out both with freshly prepared cleaner solution and with aged cleaner solution as simulation. Aged cleaner solution was left to stand for 2, 4 and 6 min after preparation, before the cleaning tests were started.

The results are shown in the figure. The test specimens are numbered from top to bottom and were cleaned as follows:

It can be seen, that the formulation according to the invention yields cleaning results that are at least as good as, and immediately after preparation of the solution are better than, the phosphate-containing comparative formulation.

Claims

1. Solid detergent formulated for hot beverage machines, characterized in that it contains: a) at least one chelating agent for Ca and / or Mg ions selected from the group consisting of MGDA and GLDA; b) at least one complexing agent selected from the group consisting of gluconic acids, iminodisuccinate, ATMP (aminotrismethylene phosphonic acid), DTMP (diethylenetriamine-pentamethylene phosphonic acid), HEDP (1-hydroxyethane-1,1-diphosphonic acid), HDTMP (hexamethylenediaminetetramethylene phosphonic acid), PBTC phosphonic acids; and salts of the aforementioned acids; pH of from 8 to 11 in 1% by weight aqueous solution.

A cleaning agent according to claim 1, characterized in that it has a pH of 9 to 11, preferably 9.5 to 10, in 1% by weight aqueous solution.

Cleaning agent according to one of claims 1 to 2, characterized in that the weight ratios of components a) to c) are as follows: - component a) 10 to 40% by weight, preferably 15 to 25% by weight; - component b) 10 to 20% by weight; - component c) 1 to 3% by weight.

Cleaning agent according to one of claims 1 to 3, characterized in that the molar mass of the polymeric acid (component c) is 4,000 to 10,000, preferably 6,000 to 8,000.

Cleaning agent according to one of claims 1 to 4, characterized in that it further contains a non-polymeric acid, preferably an organic acid, more preferably citric acid and / or maleic acid.

Cleaning agent according to one of claims 1 to 5, characterized in that it further contains a tableting aid.

Cleaning agent according to one of claims 1 to 6, characterized in that it further contains a per-compound, preferably a peroxo-compound, more preferably a peroxosulphate.

Cleaning agent according to claim 7, characterized in that the content of a per-compound is less than 3% by weight, preferably 1 to 2.9% by weight.

Cleaning agent according to one of claims 1 to 8, characterized in that it does not contain water-insoluble solids.

Cleaning agent according to one of claims 1 to 9, characterized in that it does not contain a disinfectant selected from the group consisting of quaternary ammonium compounds, amines and active chlorine-containing compounds.

Use of the detergent according to one of claims 1 to 10 for cleaning machines for hot drinks.

Use according to claim 11, characterized in that the machines for hot drinks are designed for the production of coffee, tea and / or cocoa.

Use according to claim 12, characterized in that the detergent is used to clean coffee pipes and milk pipes.

Use according to one of claims 11 to 13, characterized in that the detergent is further used to clean a milk foam compression unit.