Dusting of cheese shreds with an anticaking agent
Cheese shreds are either a consumer product or a semi-finished product used in the prepared-meal industries. To prevent the agglomeration of the shreds after grating and until their use, they are coated with an anticaking agent. There are several ways to do it.
Shreds are made by grating either traditional cheeses (Mozarella, Emmenthal, Cheddar) or specially processed cheese for this purpose. It usually has a relatively high moisture content and fat content, between 30 – 40% each. These amounts cause the agglomeration of the cheese after grating; thus showing a defective aspect or preventing the further processing in automatic dosing machines.
The powder coating is based either on :
- Cellulose, microcristalline cellulose
- Potato, wheat starch
- Talc, silicium
In some case, powder flavours can be added into the mix to convey a distinctive aroma profile
How does it work?
The coating process depends on the context. It consits merely in dosing and mixing. They may occur in different ways. The operation may consists simply in adding the powder simultaneously with the cheese in the grating machine. It has drawbacks : agglomeration in the machine, pollution outside the machine, uneven distribution. It rather occurs in a dedicated system.
Dosing at a critical point of the system
A dedicated system may consists in a rotary tumbler or a rotating screw whose length and diameter are calculated to accommodate the product flow. The coating relies on the mechanical dispersion caused by mixing.
Dispersion can be enhanced by distributing the powder prior to its fall onto the product by:
- Blowing air. Electrostatic is recommended to prevent pollution,
- Using a vibratory scarf tray.
The product throughput needs to be recorded precisely (weigh band feeder, for example) in order to adjust the powder doser. The powder doser can be of the volumetric or gravimetric type, the latter offering a better precision and traceability.
It is commonly a continuous operation.
The twin-screew coating system is inserted in line with the cheese grating and dosing. Rotation speed is adjusted to achieve the required friction and residence time. The residence time is relatively short as powders tend to disperse easily. The cheese is not sotred but sent directly to the packaging lines.
How do you measure your success?
Key quality features
Although obvious, evaluation can be detailed.
The cheese shreds must not pack when pressed. No cheese or powder lumps should remain
The cheese shreds must remain intact
No powder excess should appear in the packaging
Key quality parameters
Although a simple process, its application can be resolved in multiple ways but with similar constraints
In some cases, dosage is made during shredding or conversely at the packaging machine. A specific system is recommended
System design and operation
Multiple systems are suitable. The main design parameter is how the powder is applied to the product, mixed and controlled.
The dosage of the powder must follow consistently the flow of product which is often varying