Technical
Alkaline vs Acidic Milking System Cleaners: When to Use Each
Why Milking Circuits Accumulate Two Types of Soil
Every time a milking circuit runs, it accumulates two distinct categories of deposits: organic soil and mineral soil. These require different chemistry to remove, which is why effective milking system cleaning always uses two types of products in rotation.
Organic soil is the residue from milk itself: fat, protein, and milk sugars that coat pipeline surfaces, rubber components, and heat exchanger plates after each milking. If not removed, organic deposits form a substrate for biofilm — structured communities of bacteria embedded in a protective matrix that is orders of magnitude more resistant to disinfection than free-floating bacteria. Organic soil is removed by alkaline cleaning.
Mineral soil comes from the calcium, magnesium, and phosphate naturally present in milk and in the hard water used for cleaning. These minerals precipitate out of solution when heated and accumulate on metal surfaces as limescale and milkstone — a mixed organic/mineral deposit that forms when residual protein is incorporated into the mineral matrix. Mineral deposits are not removed by alkaline cleaning and in fact alkaline conditions can accelerate their formation. Mineral soil is removed by acid cleaning.
The Alkaline Wash
The alkaline wash cycle runs after every milking session. Products used for this cycle include:
- MS CLEAN — alkaline high-chlorine cleaner, MS product family
- CLS CLEAN — alkaline high-chlorine cleaner, CLS product family
- STAB AC — stabilized alkaline cleaner
The alkaline active (sodium hydroxide or equivalent) saponifies fats, converting them to water-soluble forms. Chlorine in the formula oxidizes protein soil and provides sanitization. Hot water (above 65°C at the start of the cycle) is essential for fat removal — alkaline cleaning at low temperature will not effectively remove milk fat from circuit surfaces.
The Acid Descale
The acid descale cycle runs less frequently than the alkaline wash — typically every one to three days depending on water hardness and milk throughput. Products used include:
- MS CID — phosphoric acid-based descaler, MS family
- CLS CID or CLS CID N — acid descalers, CLS family
- STAB AD — stabilized acid descaler
Acid descaling dissolves calcium and magnesium mineral deposits from circuit surfaces. Acid cycles generally run at lower temperatures than alkaline cycles (high heat combined with acid accelerates corrosion of equipment). Inhibitors in the formulation protect stainless steel components and rubber seals from acid attack during the cycle.
Frequency and Protocol
A typical two-stage cleaning protocol looks like this:
| Cycle | Frequency | Product type |
|---|---|---|
| Alkaline wash | After every milking | MS CLEAN / CLS CLEAN / STAB AC |
| Acid descale | Every 1–3 days | MS CID / CLS CID / STAB AD |
Operations in hard water areas should descale more frequently. Farms seeing milkstone buildup despite regular acid cycling should reduce the interval between acid cycles, increase concentration, or check water softener function.
Switching between alkaline and acid without thorough rinsing between cycles risks chemical reaction between the two — always rinse the circuit with clean water between the alkaline and acid cycles.
Contact AgroLyne for guidance on two-stage cleaning protocols and product selection for your circuit configuration.