The clean solution

    "Switching detergents can interfere with the entire washing process."

    Interview with Meiko dishwashing chemicals experts Martin Schömezler and Dr Johannes Lenz

    Some people might think it's an exaggeration when professional dishwasher manufacturers caution about the use of just any detergent. But you will realize the importance of this advice when your glasses come out of the dishwasher with streaks and food is still stuck to the plates.

    Martin Schömezler (image left), Head of Sales Chemistry at Meiko und und Dr Johannes Lenz (right) Research And Development Chemist at Meiko know that the subject is a science. 

    As head of sales, Martin Schömezler is very familiar with the day-to-day conditions and challenges present in the restaurant industry. 

    Dr Johannes Lenz he does research in the Meiko laboratory and is significantly involved in the further development of Meiko Active's chemical products. In an interview, the two experts explain what good detergent chemistry is all about.

    Mr Schömezler, why is it important for restaurateurs and hotel owners to know about detergents and the right dosage?

    Martin Schömezler: Basically, the top priority for the operator of a commercial dishwasher is a hygienically perfect result and clean, shiny dishes. The image of his or her business is at stake. Having a high-quality dishwasher is not sufficient to meet your own demands and the legal requirements. The detergent must be correctly dosed and precisely matched to the needs of the user. The washing process is a symbiosis of mechanics, time, temperature and chemistry. If any of the latter is off the mark, then the entire process is affected.

    "The consequences of a wrong dosage only become apparent gradually – after it's already too late."

    Dr Johannes Lenz

    What is the most common mistake users can make when selecting and dosing detergent?

    Martin Schömezler: Errors in the application of detergents are often not easy for the user to notice at first glance. That means it's all the more important for employees in the restaurant and hotel industries to be informed about detergent use.

    How can a commercial dishwasher be damaged if the wrong detergents are used?

    Dr Johannes Lenz: Using the wrong detergents can substantially impair the wash process in the dishwasher. In the worst case, the use of foaming products can totally compromise the washing performance of the dishwasher.

    Martin Schömezler: The use of manual dishwashing detergents, for example, produces significantly increased foam formation instead of the desired washing result. The washing pressure of the dishwasher is also negatively influenced by the use of manual dishwashing detergents. Which makes a poor result inevitable.

    Dr Johannes Lenz: Inappropriate detergents can also be detrimental to the dishwasher by causing an irreparable corrosion process to occur inside the dishwasher.The average user is not able to determine which detergents are suitable and which are not. Most problems occur due to the continuous use of such detergents. The effects only become apparent gradually over time.

    What are the consequences of using too much or too little detergent?

    Martin Schömezler: Using too little detergent might mean the required pH value for alkaline detergents is not reached. The consequences of that are poor washing results and poor hygiene. Using too much detergent causes residual alkalinity to remain on the washware. The washware then looks dull and feels soapy, making it totally unsuitable for guests to use. Using too little rinse aid leaves spots on washware and dishes will remain wet after the rinse cycle. Using too much rinse aid leaves behind streaks on the washware and the surface will also look dull.

    Meiko Active


    The Meiko Active product portfolio offers cleaners for commercial use and ensures cleanliness and hygiene wherever they are used. Catering businesses, hospitals, nursing homes, restaurants, canteens and cafeterias use the products.

    The portfolio includes

    • Basic cleaner for cleaning floors, sinks and gullies
    • All-purpose cleaner for washable surfaces, waste containers and refrigeration equipment
    • Freezer cleaner for cleaning the interior of freezers and freezer cells
    • Grease remover for cleaning combi steamers, baking and grilling equipment, grease filters and extractor hoods
    • Glass cleaner for glass surfaces, windows and mirrors
    • Dishwashing detergent and rinse aid for cleaning kitchen utensils, pans, cutlery and dishes

    So you can't do without an expert?

    Martin Schömezler: That's right – and that's because there are always different requirement profiles and general conditions on site. For example, water harness varies, as does the soiling of washware. The specialist analyses the individual components and understands the washing process as a complex structure, then selects the right products and sets the appropriate dosage for the operator.

    What must a detergent contain in order for washware to become hygienically clean?

    Dr Johannes Lenz: In order to achieve a hygienically perfect result, the entire washing process must be optimally coordinated. Orientation in that regard is provided by the DIN standard for commercial dishwashing. These standards specify the required temperatures and contact times.The detergent, to consider one component more closely, is responsible for the alkaline pH value in the detergent bath. This has a decisive influence on the washing result and supports the hygienic condition of the dishwasher.

    What problems will I have if I decide to switch to another product, for example to a generic product?

    Martin Schömezler: If a system is properly set up and functions optimally, then changing one component can unbalance it. Switching to another product made from other raw materials will result in a poor washing result or may leave behind deposits in the dishwasher.

    "A change of detergent can interfere with the entire rinsing process."

    Martin Schömezler

    What should a detergent contain to make it especially suitable for washing glasses?

    Dr Johannes Lenz: Glass is a very sensitive material. Not only is there an increased risk of breakage, but glass may also corrode. This means the washing requirements are particularly high. In our experience, glass is particularly vulnerable when mildly alkaline detergents are used. And rinse aids must contain special surfactants to ensure optimum wetting of the glass surface.

    What must the restaurant owners pay attention to if they want a good detergent for porcelain or ceramics?

    Dr Johannes Lenz: A good detergent for diverse types of washware consists of a balanced combination of water softener and alkaline agents. Depending on the requirement profile, bleaching agents can further optimise the detergent.

    Detergents & rinsing additives: These requirements must be observed by restaurateurs!

    Dr. Johannes Lenz knows that the use of commercial detergents requires a certain amount of attentiveness. There are also some bureaucratic aspects to consider, which put the gastronomy sector partly under massive pressure.

    As an employer, you should therefore pay attention to the following points:

    1. Employees must be trained in the handling of hazardous substances. Instruction on this subject must be carried out once a year on the basis of operating instructions and the instruction must be documented in writing.

    2. When handling hazardous substances, employees must be provided with appropriate protective equipment.

    3. When storing detergents, the Water Resources Act must be observed: Detergents must be stored in such a way that adverse effects to the environment do not occur.

    4. Problems often occur because the wastewater limit value parameters are exceeded after the grease trap. In this case it makes sense to contact the product manufacturers.

    5. The functionality of the grease trap must be guaranteed. The DIN standards for grease traps, which define the design and maintenance in more detail, provides orientation here. Emptying the unit should be done at least once a month.

    6. When disposing of empty containers, it must be ensured that they are completely empty so that they can be recycled.