Membrane filtration, compared to more traditional ways of manufacturing fresh fermented dairy products, offers a flexible, high yield process solution which is already well proven in the dairy industry and can be adapted to give producers the ability to increase production capacity and produce wider product varieties from a specific milk supply.

The main advantages of applying membrane filtration for fresh fermented products include:

• Easy adaption of the Membrane plants to variations in the feed/product quality or the downstream line capacity.
• Avoid the need to add external dry matter sources if the product range is based on origin protected milk types (geographical, animal, etc.).
• Generally, the membrane technology provides a higher process yield compared to the use of centrifugal separation.
• Low concentration levels allow concentration of unfermented milk. The resulting sweet permeate can be used in the production of other dairy products.
• Low fat loss when concentrating fermented whole milk and cream.

 

How It Works

Cross flow membrane filtration can be used to separate and concentrate milk components. The process uses a flow parallel to the membrane surface to reduce blockage of the membrane pores and thereby optimize the flow through the membrane. As with other membrane separation processes, the membrane flux (l/m²h) or the flow through the membrane is influenced mainly by the feed quality, the retentate quality and the flow and pressure conditions at the membrane surface.

 

Types of Systems

Microfiltration (MF)

Microfiltration is based on a membrane with a very open structure allowing most dissolved substances to pass whereas non-dissolved particles, bacteria, spores and fat globules are rejected. Depending on the specific application, membranes and process parameters are chosen to secure optimal performance of the plant.

 

Ultrafiltration (UF)

Ultrafiltration for concentration of milk or whey is widely used in the dairy industry. UF concentration is used as a concentration step in the process of making different whey or milk powder products. Furthermore, fresh cultured cheeses like cream cheese, Feta and Queso Fresco can be produced by UF concentration with substantial higher yield.

 

Nanofiltration (NF)

Nanofiltration is a RO process in which a more open membrane allows small monovalent ions such as sodium and chloride to pass. This means that NF combines concentration (like RO) and partial demineralization. The NF process can be used for a wide range of applications in the dairy industry, such as demineralization of whey, milk and permeate from UF of milk or whey.

 

Reverse Osmosis (RO) 

Reverse Osmosis filtration is based on a very dense membrane that rejects virtually all substances except water. This is possible due to high system pressure. RO is used for concentration of liquids with higher solids levels, depending on application. The purpose of RO can be pre-concentrate prior to evaporation to minimize transport costs or to increase capacity in different dairy processes.

 

Dairy Applications

Strained yogurt and fermented milks

• Skyr (Iceland)
• Greek yogurt (Greece)
• Shrikhand and Chakka (India)
• Ymer (Denmark)

 

Fresh fermented skimmed milk cheese

• Quarg (Germany)
• Topfen (Austria)
• Skimmed milk soft cheese (UK)
• Baker’s cheese (USA, European, and some eastern countries)
• Pâte Fraîche (France)
• Tvorog (Russia)

 

Fresh fermented full fat cheese

These products originate from skimmed milk cheese but with added milk fat. The cream may be fermented or unfermented before dosing into the skimmed milk cheese after fermentation.

 

Cream cheese and double cream cheese

Cream cheese types often have fairly high viscosity at lower temperatures and so hot-filling is commonplace. This creates a suitable speed for the filling process; obtains desirable product firmness, and secures a long shelf life.

 

Mascapone

Mascarpone is most often made by adding a food grade acid, such as citric or tartaric acid, to the cream instead of using a dairy starter.

 

Why Invest with ITT Flow Technologies

ITT Flow Technologies has many years of experience in supplying membrane solutions for the dairy industry. It is at the heart of our business to combine sound economics with an optimized environmental foot print.

• Have more than 1,200 reference membrane plants worldwide
• Offer both stand alone and line integrated membrane solutions
• Offer both basic manual and highly automated membrane solutions
• Offer Microfiltration (MF), Ultrafiltration (UF), Nanofiltration (NF), and Reverse Osmosis (RO) systems and combinations here off
• Offer Innovation Centers for extensive pilot testing and validation on a pilot scale, with customer specific products 
• Is recognized for pioneering innovative dairy membrane applications
• Has worldwide experts and local contacts