Feed safety and quality are key issues for all companies handling feed and can have serious consequences when control is lost. A systematic approach is required for reducing risk and improving quality.

Control principles may be divided into 3 categories:

1. Efforts to prevent contamination
• Prevention of contamination from entering the feed mill. 
• Prevention of contamination within the feed mill.
• Preventing contamination also involves controlling dust and optimal house keeping.
2. Procedures designed to kill pathogens such as Salmonella. Killing pathogens involves thermal processing.
3. Efforts to reduce microbial multiplication within the plant; discovering microbial growth niches and reducing conditions that lead to growth.

We present 40 tips to ensure good hygiene practices within your feed mill.

 Raw materials intake

1. The quality of ingredients used for feed production is important because what animals eat can affect the quality of meat and eggs.The ingredient quality control of a feed mill is an important first step in safeguarding the health of animals on the farm.
2. Cleaning during intake of the (raw) materials to prevent feed contamination and damage to the equipment.

Air handling

3. The feed milling facility’s air handling system should be segregated by location. Air inlet areas for pellet cooling can be a major source of microbial contamination and should be designed and located so as to minimize contamination of finished pellets by providing clean incoming air.
4. All intake air for the process passes HEPA filters (anti bacteria filters) at entrance to the process as for cooling and hot air sterilization of the pelleting lines.
5. Air handling systems should be cleaned thoroughly on a scheduled basis.

Water usage

6. Water used in feed production should meet hygienic standards and must be of suitable quality for animals.

Process control

7.  Automatic sample taking raw materials before intake to check material quality.

8. Buildings and equipment used to process feed and raw materials should be constructed in a manner that permits ease of operation, maintenance and cleaning and minimises feed contamination.
9. Process flow within the feed mill should be designed to minimise feed contamination.
10. Each feed processing line may be physical separated by placing them each in separate compartments to prevent or minimize cross contamination through the air between the feed processing lines.

Storage

11. Storage areas for raw materials and finished products should be separated to prevent cross contamination.
12. Storage of raw materials, processed materials and finished feed in round or rounded silo’s, bins and hoppers to prevent sticking of materials (creating mass flow in the silo).
13. Bin cleanliness in the feed storage area is essential and should be monitored on a regular basis.
14.  C.I.P. (Cleaning In Place) units in every liquid storage tank for optimum cleaning when changing or refilling liquids.

Transport

15. All piping executed in round piping with flow angles >60 degr. to prevent sticking of materials and optimum product flow through the process lines.
16. Transport equipment such as bucket elevators and chain conveyors are equipped with anticontamination bottoms and heads to minimize the residue of materials.
17. Application of Stainless Steel parts to prevent contamination and corrosion caused by condense or aggressive products.

Dosing

18. 100% automated dosing of all feed formula components (no hand tipping).

Mixing

19. Only dry mixing of the formula components in the mixing stage, to minimize contamination in the batch mixer and to maintain optimum mixing homogeneity.

Pelleting

20. Application of a closed oil lubrication system, eliminating contamination of the feed with grease.
21. Application of food grade grease and oils.

Cooling

22. Coolers placed in sealed rooms with overpressure atmosphere to prevent cross contamination trough air.
23. Camera guarding inside the coolers for easy checking complete emptying of the coolers.

Air handling

24. Separated aspiration air outlet channels for dry and wet process steps and process lines to prevent cross contamination inside the channels.
25. Decentralized aspiration on all transport equipment.

Process control

26. Anti-contamination software. Safe flow of recipes in relation to contamination.
27. Safe control by weighing silos and bins in each process step to prevent cross contamination caused by residues.
28. Automatic sample taking in every feed processing step up to and until truck loading to control, track and trace the feed production performance.

29. Care should be taken to minimize deterioration and spoilage at all stages of handling, storage and transport of feed and feed ingredients.
30. Feed spills should be cleaned up immediately.
31. Special attention to the internal and external finishing of equipment and installation parts such as internal smoothening of welds, closed profiles for supporting structures for equipment and inclined reinforcement ribbons to bins and hoppers for minimum dust collection and easy housekeeping.
32. Vertical placed cable trays to prevent dust collection.
33. Floors and walls in concrete structure with a finishing coating for optimum hygiene and housekeeping. 
34. Vacuum cleaning system at each floor and compartment to enable frequently and easy housekeeping.

By the application of a long term vessel pathogens, such as Salmonella bacteria, will be killed. This process takes place when the temperature of the meal is higher then 85°C and a retention time lasts 4 minutes (240 sec) or longer.

This treatment is especially important for layer feed: Eggshells can contain Salmonella.

35. The Long Term Vessel conditioner, placed after the steam mixer, significantly improves the process of feed conditioning. This has a major effect on biosecurity while also optimizing the nutritional quality of the feed and enhancing the pelletability of the product.
36. Hot start steam mixer guarantees a minimum demanded press meal temperature at start up, preventing spoilage of the first meal.

37. Dry feed and feed ingredients should be kept dry in order to limit fungal and bacterial growth.
38. All equipment in the heat treating and cooling process stage carried out with tracing and insulation to maintain required process temperatures and prevent condensation inside the related process equipment.
39. Counter flow Hot Air for pre heating and sterilization of the pelleting lines.
40. Fully welded liquid and steam piping lines to guarantee leak less liquid dosing again to prevent bacteria growth.