Choosing the Right Ayran Process Tank
Ayran is a critical dairy product with a large consumption volume in the Turkish and Middle Eastern markets. The quality, taste and shelf life of ayran depend not only on the quality of the milk used, but also on the design of the settling and homogenisation tanks used in the production process. An incorrectly designed tank can cause the product to foam, separate fat and prevent the stabiliser from dispersing homogeneously.
At ÖNSA Makine, we offer optimised tanks that support every stage of your ayran process.
1. Critical Functions of the Ayran Process Tank
The ayran process essentially takes place in four stages within the tank, and the tank's design must accommodate these stages:
Fermentation and Resting: After adding the yoghurt culture, the product is rested at a stable temperature (usually 42°C - 45°C) for a specific period. The tank's insulation is vital for maintaining temperature stability during this stage.
Breaking (Agitation): Bringing the curdled yoghurt to a homogeneous liquid consistency. This stage should be carried out using a suitable low-speed mixer to prevent structural damage (oil separation) or excessive foaming.
Adding Salt and Stabilisers: Ensuring that salt and stabilisers are distributed evenly and completely throughout the product in the tank.
Cooling and Storage: Rapidly cooling the product to between 4°C and 6°C before packaging and holding it at this temperature.
2. Design to Prevent Foaming and Fat Separation
The biggest problem faced by ayran producers is excessive foaming during mixing and the subsequent separation of oil to the surface inside the tank.
Mixer Type: Low-speed, wide-bladed or propeller-type mixers should be preferred over high-speed turbines. These mixers gently stir the product without exposing it to air, minimising foam formation.
Shaft Position: Mounting the mixer shaft slightly off-centre rather than in the exact centre of the tank prevents vortex formation and consequently foaming.
Jacketed Cooling: The cooling process should be carried out via a jacket applied to the tank wall, and temperature control should be precisely managed using PID systems.
3. Hygiene and Material Standards
The slightly acidic nature of ayran requires careful selection of tank materials.
Stainless Steel Quality: As ayran falls under the dairy products category, AISI 304 is generally sufficient. However, AISI 316 may be preferred for ayran recipes with high salt content or for tanks requiring a long service life guarantee.
CIP Compatibility: There should be no dead zones inside the tank. Cleanable hygienic valves and CIP spray balls should ensure complete and residue-free cleaning.
ÖNSA Makine manufactures special Ayran Process Tanks that meet the unique requirements of your ayran process, minimising foaming and oil separation issues.
