FAQ about milk refrigerators and milk coolers

Why do you even need a milk refrigerator?
Can you do without one when using UHT milk?

funny picture from a milk bag with bacteria
bacteria are having a party

The sun is shining, the temperatures are climbing ever higher, perfect for a latte macchiato, café au lait or a cappuccino on the terrace. But it is precisely on such days that you have to be particularly careful.
For the perfect coffee enjoyment of coffee specialties with milk, it is not only important to have a good coffee machine in order to extract the perfect taste from the coffee beans, it is also important that the milk is constantly cooled in order to meet the hygienic requirements. Further the cooling is important for preserving holding the typical full-bodied milk taste.

Due to its composition, milk offers an optimal breeding ground for germs and bacteria. In order to inhibit their growth, the storage temperature of the fresh milk is around + 4°C, depending on the manufacturer’s instructions. When milk is stored outside of refrigeration or insufficient refrigeration, the bacterial load in the milk increases exponentially. This can have health consequences. It should also be noted that higher temperatures promote the proliferation of lactic acid bacteria. These then make the milk taste sour.

A common misconception is that UHT milk in opened packages does not need to be refrigerated. You often see unrefrigerated tetra packs standing next to fully automatic coffee machines. Here, too, bacteria and germs can contaminate the milk through airborne transmission and multiply, especially in summer temperatures. What’s particularly tricky here is that long-life milk can spoil without acidification and you can’t taste or smell high levels of germs.

Why are the milk fridges equipped with containers?

Tetra packs and other sales packaging are usually also transport packaging. These are in the free flow of goods and are often contaminated from the outside. These contaminants should not be brought into the milk refrigerator. The Federal Center for Nutrition (BZfE) in Germany, a department of the Federal Agency for Agriculture and Nutrition (BLE) in Germany, points out that opened milk cartons (regardless of whether fresh milk, UHT milk or ESL milk) should be stored in closed, food-safe containers to protect them from flying around. To protect germs and bacteria and to store it continuously at a constant temperature that is optimal for the milk. A milk refrigerator with a container meets this requirement. All of our milk coolers are equipped with matching milk containers that have a lid. This means that no bacteria are introduced when the filled milk container is transported from the kitchen to the machine.

4 liter milk container for milk cooler
4 liter milk container

What is the difference between a milk container and a duo milk container?

A milk container is a container into which only one type of milk can be poured. A duo milk container is a container that is divided into two separate reservoirs on the inside. If desired, you can also pour two different types of milk into this container. For example, a combination of UHT milk and fresh milk or fresh milk or soy milk would be conceivable. The milk is in one container, but the two chambers are separate from each other. It is also possible to use types of milk with different fat contents. The possible combinations are very diverse.

technical sketch single milk container
single milk container
technical sketch duo milk container
duo milk container

Mechanical thermostat versus digital thermostat?

The first advantage of an electronic thermostat is that the internal temperature is displayed on the front of the device using a digital display and you do not have to open the door to determine the temperature inside the device.

digital thermostat from milk cooler
digital thermostat

Another advantage is that you can adjust the temperature that you need for the respective type of milk to the exact degree. The different types of milk sometimes require different temperatures. This can be responded to very precisely using an electronic thermostat.

What is a milk level indicator and how does it work?

A milk level indicator does not show the amount of fuel remaining, like a fuel gauge on a car. The milk level display can be compared to the reserve display in the vehicle. If the level of the container falls below a certain level, an alarm is given. On most models this is a red lamp that turns on. Some devices also make a buzzer sound. However, this can also be suppressed at the operator’s request. When the alarm goes off, you can usually still draw a few specialty coffees with milk, so you still have time to refill the container or replace it with a new, filled container. The following image shows a schematic representation of the level indicator in one of our milk refrigerators.

What is a milk tube feedthrough?

Almost all of our devices are supplied with a milk hose feedthrough. The milk hose must be routed through the housing of the milk cooler in order to connect the milk hose to the coffee machine or fully automatic coffee machine. If we have already equipped the devices with a pre-drilled milk hose bushing, you do not need to drill any holes in the milk cooler housing. Seen from the inside, a milk hose bushing looks like the picture below.

milk hose passage view from inside the milk cooler
milk hose passage view from inside the milk cooler

Depending on the model, the bushings are located on the left, right and sometimes also at the top of the machine. Some models not only have one milk hose duct on each side, but 2. The reason for the two milk hose ducts arranged next to each other is that some devices can be equipped with a duo milk container. If you have two types of milk, you will of course need two separate suction hoses for the milk. When delivered, the holes are each closed with a plug.

plug for milk hose passage
plug for milk hose passage

This can be easily removed by you, but can also be reinserted. This makes it possible to only remove the plugs that are needed to pass through the milk hose(s). All other plugs remain in their holes.
Please note that some milk refrigerators do not have milk hose ducts. With these, you have to make the holes for the milk hose passage(s) in the machine yourself. The respective number and position of the milk hose bushings available ex works can be found in the description of the device.
Please also note the explanations on the subject of milk hose feedthroughs for bag-in-box devices.

What is special about a milk temperature sensor?

Devices with a milk temperature sensor are equipped with a special milk container. These special containers have a round metal contact plate in the middle on the bottom. This part very quickly takes on the temperature of the milk in the container. When the container has been inserted into the device, this metal contact plate is located on a corresponding metal contact plate in the bottom area of the milk refrigerator. Here the temperature is then detected by an electrical thermocouple and displayed by the electronics on the digital thermostat on the outside of the device.

4 liter milk container for milk cooler
Milk container with metal contact plate in the bottom area
temperatur sensor at the bottom of a milk cooler
Metal contact plate in the bottom area of the milk refrigerator

The special feature of this technology is that the temperature of the milk in the container is displayed and not the interior temperature of the milk refrigerator. The electronics control the on and off points of the cooling compressor according to the milk temperature.

What does “BiB” or “Bag in Box” mean?

BiB packaging usually consists of a plastic bag in which the product is located and an outer packaging made of cardboard, which serves to protect the plastic bag inside and, thanks to its cuboid or cube shape, makes it easier to handle during transport and use. The bag-in-box packaging protects the food from air, light, heat and external environmental influences. However, every BiB packaging can be constructed differently and also vary in size.

square bag in box with milk
square bag in box
cuboid bag in box with milk
cuboid bag in box

Are there milk hose bushings on the devices from the MC 75 / MC 130 and BiB series?

The devices in the MC 75 and MC 130 model series have two milk hose bushings ex works. These are located in the upper area of the milk cooler. The milk hose feedthroughs look a little different than the other models but can be used in the same way.

technical sketch of how to route the milk hoses in a milk cooler that is located below the coffee machine
how to route the milk hoses for milk coolers MC 75 / MC 130

The milk refrigerators with “BiB” in the model name do not have a milk hose feedthrough. This must be drilled by the specialist company that installs the milk cooler in the furniture. There are sketches showing the area where the hole can be made without damaging the milk cooler.

Are all milk refrigerators suitable for free-standing installation next to or under the coffee machine?

No, the milk refrigerators from the MC 75 / MC 130 and BiB model series may not be operated free-standing. These models are devices that must be installed in a cabinet, counter or other piece of furniture. It can be installed, for example, underneath the coffee machine.

milk fridge under a coffee machine
milk fridge MC 75 / MC 130

In the milk refrigerators of the aforementioned model series, the cooling compressors are not covered by the housing. There is therefore a risk that operators or other people could suffer an electric shock if the milk refrigerators are not installed in closed furniture.

Can I install the MC 75 / MC 130 and BiB models myself?

No, you should not install the milk refrigerators from the aforementioned model series yourself. On the one hand, the installation must be carried out in such a way that there is no risk that a person can later access the electrical system of the device during operation and possibly suffer an electric shock. Therefore, the devices must always be installed in closed furniture or measures must be taken to ensure that access cannot occur accidentally. On the other hand, the devices must be installed in such a way that the cooling compressor, which sits on the back of the milk cooler, receives enough fresh air. In addition, the air flow in the furniture must be such that the exhaust air that occurs while the cooling compressor is running is also directed out of the furniture. Therefore, the installation of the aforementioned models may only be carried out by specialists.

Why are there milk coolers with a capacity of more than 10 or even 30 liters?

milk cooler with 2 x 15 liter milk container and glass door
MC 130 milk cooler with 2 x 15 liter milk container

In recent years there has been an increased demand for coffee specialties. Depending on the location of the machine, a good 50% of the portions taken are now served in the form of coffee specialties. With modern fully automatic coffee machines, preparing such hot drinks is no problem. However, preparing such coffee specialties often requires a significant amount of milk per cup dispensed. The milk used, whether fresh milk, UHT milk or soy milk, must be cooled. However, fully automatic coffee machines often do not have any, or not sufficiently large, cooled milk compartments. In these cases, the milk should be stored outside the coffee machine in a milk refrigerator. In the beginning, devices with a capacity of 1 liter to 4 liters of milk were often sufficient. However, the coffee specialties on offer became increasingly high quality and there was suddenly a need for milk refrigerators with two separate milk compartments in order to store different types of milk or milk with different fat contents. The very high taste quality often increased sales. That’s why there are companies today that can no longer manage with a milk volume of 10 liters per day and therefore have to refill the milk storage container several times a day. In order to save themselves this work, companies like to use milk refrigerators in which larger quantities of milk can be kept cool. The milk is now also available in bag-in-box packaging. These bag in box packaging usually require milk refrigerators with a larger volume in order to store the bag in box packaging there.