Using Rotary Sifters for Sanitary Applications

When it comes to food, 15 million pounds (about 6.8 million kg) of food products are recalled every year in the United States, with these recalls costing on average about $10 million each. But it’s not just about money, as one out of every six Americans becomes sick due to a food-related illness annually, with around 3000 of these dying. For this reason, manufacturers looking at rotary sifters for sanitary applications must use one built with a hygienic design in mind.

Hygienic Design for Rotary Sifters

When selecting a rotary sifter, a hygienic design allows operators to clean the machine without resulting in too much production downtime. Besides the food and beverage sector, many other industries use rotary sifters with hygienic designs. The construction of rotary sifters for sanitary purposes must ensure the machine can be cleaned quickly and thoroughly to mitigate any contamination by microorganisms while guaranteeing efficient production processes. How these rotary sifters are constructed helps prevent contamination of products by foreign material and pathogens.

What is Hygienic Design?

The term hygienic design has been a buzzword for years in the food and pharmaceutical industries, but it’s much more than just an empty phrase for a machine like the rotary sifter. Hygienic design requires that rotary sifters for sanitary applications meet specific criteria to reduce the chance of contamination, whether biological or nonorganic. For this reason, certain principles are followed when designing a rotary sifter. Hygienic design requires careful planning when designing rotary sifters for sanitary applications, and these practices ensure simpler cleaning and make other maintenance easier.

Rotary sifters for sanitary applications require hygienic designs, including: 

• Accessibility: A hygienic design for a rotary sifter means easy cleaning, sanitizing, inspection, and maintenance; disassembly for cleaning or other purposes requires that any air hoses or vacuum lines be transparent and have a clearance of about a foot (30.48 cm) from the ground.
• Cleanability: Maintenance workers must access the equipment until it feels, looks, and smells clean, destroying harmful microbes that could cause health issues. This can lead to potential recalls of the end product.
• Cleaning protocols: The whole design of rotary sifters for sanitary applications should expedite the facility’s sanitation process, with authorized protocols for cleaning and sanitizing the equipment.
• Compatible materials: The materials from which a rotary sifter is made should resist degradation while also being nonpermeable, nontoxic, and uncoated; 300 series stainless steels and plastics like HDPE (high-density polyethylene), PU (polyurethane), and UHMW (ultra-high molecular weight polyethylene) work well with rotary sifters for sanitary applications.
• Integration: Rotary sifters need to work well within the overall processing system; for example, pneumatic mechanisms shouldn’t blow air or gas across the processing area as this will result in pollutants throughout the system.
• Maintenance: Enclosures used to facilitate maintenance should not be placed within the processing area, and cabling must be organized and leave enough space for comprehensive cleaning.
• Performance: Components like bearings, control panels and motors shouldn’t lie within the product processing area to prevent buildup on them; if compressed air is used during processing, it ought to be filtered and dry.
• Preventing buildup: Product or any other substance that builds up on a rotary sifter’s surfaces presents a sanitation issue, especially in areas where material passes during processing; these areas should feature angled surfaces and drainage to prevent buildup.
• Sealing: Ideally, hollow areas shouldn’t exist, but if they are required in the design, they should be airtight.
• Surfaces: Surfaces should be as smooth as possible. Surfaces not in contact with the product have a roughness average of 125 microinches (3.175 micrometers), while surfaces in contact with the product require a 32 microinch (0.8128 micrometer) roughness average. Additionally, internal corners should have a 1/₈ inch (3.175 mm) radius, while welds also require sufficient smoothness.

Various industries may have different recommendations for hygienic design protocols, but these general principles promote sanitation during material processing. Not only address food safety issues, but they also prevent contamination in other applications.

The Rotary Sifter: Hygienic Design for Various Industries & Applications

A hygienic design for rotary sifters is integral to many industries and multiple applications. These designs offer features that allow quick disassembly and include easy-to-clean surfaces, which help processing companies comply with regulatory requirements from agencies such as the FDA and USDA, as well as industry and other standards.

For a rotary sifter, hygienic design is used for applications that include: 

• Active pharmaceutical ingredients: Removes outsized particles within active ingredients during pharmaceutical production.
• Baby formula: Helps infant formula manufacturers meet stringent sanitary standards to ensure product safety.
• Brewing and distilling: Filters grains, malts, and other raw ingredients for making beer or spirits.
• Chemicals: Screens industrial chemicals that require exceptional purity to control contamination.
• Dairy: Hygienically screens products like casein, powdered milk or whey
• Flour milling: Separates fine particles effectively while processing grains to keep flours from becoming contaminated during baking or other food production.
• Laboratory research: Hygienically designed rotary sifters ensure accurate particle size for biotech and other lab research.
• Medications: Blends active and inactive powdered ingredients for medicines finely together before utilizing powders to make tablets. 
• Nutritional supplements: Screens powdered herbal extracts, protein powders, vitamins and other nutraceuticals for better purity.
• Personal care: Assists with processing finely powdered cosmetics, dry shampoos, face powders, talc and other personal care products.
• Poultry: Helps producers prevent illness and avoid recalls by reducing the risk of contamination.
• Protein powders: Ensures consistency and quality while preventing contamination in powdered protein supplements.
• Seasonings and spices: Ensures consistency in particle size while preventing cross-contamination.
• Sugar and candy: Screens sugars, cocoa powders, and other sweeteners to eliminate contaminants.

Rotary sifters for sanitary applications that utilize hygienic designs generally produce better-quality products with greater consistency and longer shelf lives.

Benefits of Rotary Sifters with Hygienic Designs

Many other benefits result from designing equipment for sanitary functions. With a rotary sifter, hygienic design helps increase sustainability in processing, optimizing how cleaning chemicals, energy, water, and other aspects involved in keeping machinery clean are used. As noted earlier, hygienic design of rotary sifters for sanitary applications is broadly used across many industries to comply with regulatory standards.

Rotary sifters with hygienic designs provide benefits that include: 

• CIP (clean-in-place) and SIP (sterilize-in-place) design: Using CIP and SIP protocols when designing rotary sifters for sanitary applications makes manual cleaning and sterilization easier and more consistent.  
• Decreasing corrosion: Sanitary coatings and stainless steels resist corrosive substances used in processing, enabling longer equipment lifespans.  
• Disassembly without tools: Many models of rotary sifters for sanitary applications enable maintenance personnel to quickly break down and reassemble the machine without tools, which ensures cleaning and maintenance activities can be conducted quickly while minimizing downtime.
• Diversity of materials: Rotary systems are agile and can handle active pharmaceutical ingredients, flour, industrial powders, protein powders, sugars, and other ingredients or materials.
• Handling temperature-sensitive materials: Rotary sifters work well for materials requiring lower impact sifting, especially for products sensitive to temperature extremes.
• Lowering vibrations: Rotary sifters generally operate with lower vibrations, which reduces component wear and extends equipment lifespans.
• Meeting standards: Designs that comply with agencies like the FDA and USDA as well as industry standards like 3-A improve safety while ensuring purity of products like cosmetics, foods and pharmaceuticals.
• Multiplicity of applications: Rotary sifters for sanitary applications can be used for biotech, cosmetics, fine chemicals, food processing, nutraceuticals, pharmaceuticals and other applications.
• Particle separation accuracy: Rotary sifters provide uniform particle size distribution within granulated and powdered ingredients to ensure efficient processing.
• Preventing contamination: Rotary sifters' hygienic construction features stainless steel and gap-free surfaces that prevent product buildup and contamination from microbes or other foreign material.  
• Reducing product buildup: Rotary sifters for sanitary purposes aren’t built with polished surfaces for their aesthetics but rather to simplify cleaning and prevent material buildup by ensuring exteriors are sufficiently smooth.
• Reducing waste: Through more efficient sifting, less product is lost during processing, which minimizes waste.

The use of hygienically designed rotary sifters for sanitary applications offers manufacturers many benefits, including enhanced efficiency and upheld product quality. It also lengthens the shelf life of products by reducing cross-contamination.

Prater Rotary Sifters for Sanitary Applications

Rotary sifters made by Prater Industries employ centrifugal forces that accelerate and fluidize particles against the surface of the machine’s screen. A specially fitted auger is attached to the inlet on the rotary sifter, which then moves product into a screening chamber where the rotor paddles fling product centrifugally. The finer particles discharge into a large hopper after passing through the screen, while coarser ones are forced towards the chamber’s end into a different hopper. Near-sized and oversized particles intermingle along the screen’s surface, creating a natural vibration to augment flow through the rotary sifter. Hygienic designs can be engineered into the construction of Prater’s rotary sifters and other equipment, including specialty coatings. To learn more about our rotary sifters for sanitary applications, or other purposes, contact the material handling experts at Prater today.