Powder Dispersion and Mixing in the Cheese Industry

Cheese Manufacturing Equipment

Quadro Ytron^®  High Shear Mixers are proven effective in a number of cheese and cheese related manufacturing processes. The following is a summary of the key applications in this field:

NFDM (SKIMMILKRE - CONSTITUTION)

NFDM reconstitution is a key application as milk powder and protein powders are added back into the water for the production of:

• a. Fresh cheese
• b. Cheese dips
• c. Process cheese food
• d. Cheese spreads
• e. Cottage cheese
• f. Cream cheese

Most common devices used to incorporate and disperse NFDM tend to incorporate a significant amount of air and cause agglomerates to form due to a lack of the proper amount of shearing action of the gums and caseinates. Excess air entrainment causes foaming and foaming requires time to let the milk de-aerate and can encapsulate undispersed/undissolved powder ingredients leaving scum in the milk silo resulting in more cleaning and a waste of product. Also, after the reconstitution of milk powders, the milk must be passed through a plate and frame heat exchanger (pasteurizer – often referred to as an HTST (high-temperature short-time). Air in the milk passing through the heat exchanger leads to poor heat transfer and possible hot spots and burn-on.

Download the Application Note - High Shear Mixing Technology for Process Cheese Production

Agglomerates lead to poor yields from ingredients, especially when using expensive proteins and gums. Nonhydrated/poorly dispersed material can foul the heat exchanger surface resulting in burn-on and difficult cleaning. Also, possible damage/interference can occur to downstream homogenizers (although the milk is typically filtered ahead of this step).

The Quadro Ytron^® in-line Powder Disperser is capable of dispersing skimmed milk powder, gums and caseinates into water quickly and completely lump-free, in a single-pass. One cheese-making company reported single pass concentrations at 26% by weight with the ability to empty an 800 kg super sac in 10 minutes (176 lbs/min). The inline unit has been shown to yield consistent viscosities approximately 30% higher than traditional methods. Gum hydration tanks, pre-dispersion fluids and post-filtering are not required with the use of a Quadro Ytron^® Powder Disperser. The technology is capable of producing single-pass, lump-free Xanthan gum solutions at flow rates from 15 to 120 USGPM (60-450 LPM).

Process Cheese Smoothing

Process cheese is a product made by blending various natural cheeses & cheese powders, emulsifying salts, common salt, preservatives, dry milk powder, whey and fat together, followed by cooking to liquefy the mixture to provide a homogeneous mass ready for forming & cooling. For process cheese slices, the molten cheese is cast on a roller drum, followed by cutting into ribbons, slicing, and packaging. An international cheese manufacturer approached Quadro to find a solution to problems encountered when adding reclaimed fresh cheese to their process. The addition of reclaimed cheese results in large savings of raw material costs.

However, the existing horizontal ribbon blender did not provide sufficient mixing and shearing action resulting in hard agglomerates of cheese and shortening passing to the downstream cooking and forming steps leading to off-spec, wasted product. Quadro recommended the installation of a Ytron Z^® Emulsifier following the ribbon blender to de-agglomerate and smooth the pre-mix prior to cooking. Optimal speeds and rotor/stator tooling geometries were finalized following trials on five (5) different cheese blends. The result was a smooth, consistent product with no hard agglomerates. 

Process Cheese Dips and Sauces

A large processor of cheese dips and sauces was struggling with the manufacturing of their product. The product, a high concentration of powders (maltol (30% concentration by weight)) and modified starch (9% concentration by weight) into water (50% concentration by weight) was coming out lumpy and at a low production rate.

The existing equipment, a Tri-blender style eductor, was not imparting enough shear to properly wet out the powders. A Quadro Ytron^® Powder Disperser was employed to overcome these problems. After proper tooling selection, the resulting product came out at high production rates, single pass with no lumps at 300 cps.

Cottage Cheese

A processor was blending cottage cheese (40% by wt) and skim milk, blended together with an in-tank high shear blender. The discharge had to be pumped through a plate and frame heat exchanger. Any cottage cheese lumps would stick to the plates and burn-on/clog the unit. A Quadro Ytron^® Z Emulsifier was tested successfully to size reduce 1⁄4 to 1⁄3 inch lumps. The product produced was a creamy smooth sauce. Samples left for 72 hrs experienced no degradation.

Another processor purchased a Quadro Ytron^® Z Emulsifier to complete the dispersion and hydration of gums/starches used in a cottage cheese pre-mix. Powders were initially added to a Tetra All Mix but did not disperse/hydrate sufficiently. The Z was installed after the unit to complete the hydration.

Quadro Ytron^® Advantages

• No Lumps – Agglomerate-free dispersions eliminate the need to filter, maximize the yield of raw ingredients, eliminate the need for time-consuming product re-circulation, and eliminate downstream processing issues with heat exchangers and/or homogenizers
• No air – air-free powder incorporation eliminates product foaming, and waiting for de-aeration and eliminates downstream processing issues with heat exchangers and/or homogenizers
• High-capacity solids incorporation eliminates the need for re-circulation, often resulting in batch time reductions up to 90%
• Flexibility – A portable Ytron in-line mixer eliminates the need for specialized mixing equipment to be dedicated to each and every batch vessel. The Ytron in-line mixer is easy to integrate with pneumatic and mechanical powder conveying and delivery equipment resulting in labor savings and avoidance of environmental issues due to dusting.
• Easy-Clean up – the addition of powdered ingredients through the Ytron in-line mixer eliminates tank cleanliness issues with powder build-up, reducing cleaning time and chemicals. Mixer clean-up is a snap with our USDA Dairy-approved 3A, CIP design.