Milk Storage
Raw milk is a highly perishable product, so it should be cooled as quickly as possible. Polish standards state that milk should be cooled from around 35°C to 8°C for daily collection, or to 6–4°C for every-other-day collection. 4°C is the most suitable milk storage temperature — at this range bacterial growth is inhibited, which is why more and more dairies require suppliers to cool milk to exactly this temperature.
The Shorter the Cooling Time, the Higher the Milk Quality
Cooling time also matters and should be kept as short as possible. Most cooler manufacturers set this at a maximum of 2.5 hours. One thing is certain: the shorter the cooling time, the higher the milk quality and the lower the bacteria count.
Which Cooler Should You Choose?
Dairy farms use various types of equipment for cooling milk — from can-coolers and plunger coolers, which are falling out of use, through open round or trough-style coolers, to tankers and silo tanks designed for large farms. The type of cooler depends mainly on the volume of milk produced and the milking method used.
The most popular way for dairy farms to cool and store milk is with various types of coolers (round, trough-style, tankers) — depending on the volume of milk produced. Check out our range: new Margo coolers or Margo tank silos for the largest farms.
What a Milk Cooler Is Made Of
Regardless of type, every cooler consists of the following components (numbering matches the labels in the diagrams below):
- 1Milk outlet
- 2Tank
- 3Tank lid
- 4Milk inlet opening
- 5Agitator motor with gearbox — geared motor
- 6Agitator
- 7Refrigeration unit (condenser-radiator, compressor)
- 8Controller, thermostat
How to Choose the Right Cooler Size
Choosing the right cooler size undoubtedly affects the quality of the milk stored in it. It shouldn't be too small a capacity — a cooler filled right to the top with milk will take longer to cool, increasing power use, and if collection is delayed there may be a problem cooling the next milking. It also shouldn't be too large — with a small amount of milk, there can be a problem with it freezing.
What Affects Milk Storage and Its Quality
- Room temperature should not drop below 5°C or exceed 20–25°C. Within this range, the cooling unit operates under suitable conditions without drawing excessive energy.
- The distance from the refrigeration unit to the nearest wall should be no less than 30 cm, to guarantee free airflow through the air-cooled condenser.
- The tank should take up roughly 1/4 to 1/3 of the room's floor area (a room sized at about 3×W by 3×L, where W and L are the tank's width and length).
- For a refrigeration unit up to 0.5 HP, no ventilation equipment is needed — the room just needs to allow free airflow.
- For units above 0.5 HP, a dedicated air inlet is recommended, placed in the wall opposite the condenser, fitted with an adjustable shutter.
- Warm air leaving the refrigeration unit should be vented out of the room — the warm-air outlet should be installed as high up and as far from the air inlet as possible.
- If the condenser is positioned opposite the fresh-air inlet, airflow should be adjusted seasonally: fully open during summer heat, reduced by 90–95% when the outdoor temperature drops below 5°C.
- The cooler should have its own dedicated power outlet, protected by fuses matched to its power rating, with overload protection, a residual-current device, and a phase-failure sensor (3-phase outlet).
How to Care for Your Cooler
The tank should be washed as soon as possible after the milk is pumped out, to prevent milk residue from drying onto the walls. Washing right after the tank is emptied is much easier and more effective. Always follow the washing instructions — don't use scrubbers or brushes made of metal or other abrasive materials, and remember to wash the tank's outer surface too.
- Tank washing agents should effectively remove milk residue from the wall surfaces
- They must not damage the tank surface (react with the wall material)
- They should rinse off easily
- Once a month, clean the condenser surface with a dry nylon brush (never a wire one) — a dusty condenser reduces performance, lengthens cooling time and increases energy use
Looking for the right cooler for your farm? Check out our range: new Margo coolers, Margo tank silos, Wedholms / Eurotanks, Serap, Mueller, Milkplan.
Need Help Choosing a Cooler?
We'll recommend the right type and size of tank for your farm.
Ask for Advice Call: +48 29 769 09 89