From Coarse to Ultrafine: Gram Flour Sieving Solutions for All Applications

Gram flour (besan) is a foundational ingredient across Indian and global cuisines — from sev and boondi to batters, bakery mixes, and instant products. While milling creates the powder, the screening approach determines texture, performance, and product suitability. Different manufacturers and regions require different particle-size targets; therefore, processors should choose sieving solutions based on application and required grade, not by a fixed machine sequence.

After milling, gram flour contains a mix of particle sizes. If not managed properly, this leads to inconsistent texture, lumps, or off-spec material. The following would provide a useful guide to particle-size grades and the sieving options that will best accommodate such requirements.

Understanding the Need for Precise Sieving in Gram Flour

After milling, gram flour contains a range of particle sizes. If not screened to the right specification, this can cause inconsistent texture, lumping, or off-grade product.

Depending on the application and region, the processors can aim for one or more of the following particle-size grades:

• Very Fine (≤75 µm): used for instant mixes, specialty bakery, and ultra-smooth batters.
• Fine (75–150 µm): used as a coating for batters, instant snacks, use in smooth textured applications.
• Medium (150–300 µm): for making namkeens, sev, boondi, and some extruded snacks.
• Coarse (>300 µm): either goes back to the mill for regrind, is intentionally placed in or used when course structure is desired.

Not every manufacturer needs all grades—the required specification is based on the end-use. Each targeted grade requires the right gram flour sieving technique to deliver consistent quality, avoid contamination, and meet food-safety requirements.

Roto Sifter — Best for Coarse Scalping & Safety Screening

Where it fits: removal of oversize particles, husk, and foreign matter; final check-sieving before packaging. Ideal when the primary need is contamination control and steady throughput rather than fine grading.

How it works: centrifugal sieving with a rotating paddle assembly inside a cylindrical screen distributes product evenly and forces correct-sized material through the mesh.

Key advantages

• Hygienic, enclosed design, which reduces dust and contamination.
• Built in cleaning systems (brushes/beaters) which minimize mesh blinding.
• Gentle handling that maintains the quality and aroma of the flour.
• Ideal option when it comes to using processors that need strength in pre-screening or safety inspections instead of fine grading.

Super Sivtek Separator — High-Capacity Fine & Ultrafine Grading

Where it fits: processors needing high throughput with precise grading across fine to ultrafine fractions — useful for large-scale mills or lines producing multiple fine grades.

How it works: high-energy gyratory motion spreads material evenly across stacked decks; multiple decks allow several fractions to be separated in one pass.

Key advantages

• Multi-deck to allow multiple gradation levels to be made on a continuous basis.
• High throughputs while preserving cut accuracy of fine and ultrafine products.
• Customizable mesh ranges (coarse to very fine) to match product specifications.
• Food-grade design with good construction for all GMP and HACCP environments.

Super Gyro Separator (SGS) — Precision Finishing & Polishing

Where it fits: processors looking for precision finishing and ultrafine polishing for upscale applications, or those who require only moderate capacity with tight cut points.

How it works: three-dimensional motion (horizontal + vertical + tangential) optimizes particle flow and reduces blinding, producing high separation efficiency even at fine meshes.

Key advantages

• Exceptional mesh accuracy, effective below 75 µm.
• Anti-blinding action and balanced motion increase mesh life.
• Ideal for final polishing where product texture and consistency are critical.
• The machine is for processors who want precision but not necessarily the highest throughput.

Practical Guidance: Match the Solution to Your Grade & Application

Use the following as a guideline (not a mandatory sequence):

• Very Fine (≤75 µm): Super Sivtek or Super Gyro Separator — both can achieve fine/ultrafine separation.
• Fine (75–150 µm): Super Sivtek or Super Gyro Separator — select based on throughput needs.
• Medium (150–300 µm): Super Sivtek or (possibly) Roto Sifter for coarse checks attending vibratory separators for grading.
• Coarse (>300 µm): Roto Sifter for scalping and re-route to mill as needed.

Key selection factors: desired particle-size distribution, production capacity, available floor space, and product handling characteristics (stickiness, oil content, moisture). Roto Sifter has a unique ability to ensure hygiene and coarse removal; Super Sivtek is the one that scales up to very fine grading at high volume; and Super Gyro Separator is the one that delivers precision polishing for premium flour.

Operational Considerations & Common Issues

• Blinding (mesh choking): use deblinding aids — brushes, ball & tray systems, or air-cleaning — especially for slightly oily or moist flours.
• Dust & hygiene: favor enclosed systems with proper extraction and pressure management that can meet the standards for food-grade products.
• Throughput vs. cut accuracy: finer meshes will reduce the throughput — in case both high throughput and fine cuts are needed, choose higher-energy gyratory system.
• Regrind loop: design automatic recycling of oversize back to milling obtain maximum yield.

Benefits of Choosing the Right Solution

• Consistent particle distribution — provides predictable product performance.
• Improved product quality & texture — for end use, effects products that go into the snacks, batters, bakery, etc.
• Hygienic operation — enclosed designs cause less contamination.
• Operational efficiency — reduced downtime with self-cleaning and quick mesh-change systems.
• Flexibility — these solutions can be adjusted to accommodate individual product flows and usage in different regions.

Conclusion

Precision sieving ensures gram flour quality; equipment selection should be driven by product grade, regional usage, and production capacity. Depending on these requirements the processors can select the most appropriate solution — a Roto Sifter for hygienic coarse scalping, a Super Sivtek Separator for high capacity fine grading, or a Super Gyro Separator (SGS) for precision finishing. Some processors may combine systems for specific flows; others will rely on a single machine tailored to their needs.

Both Super Sivtek and Super Gyro Separator can also offer multi-level gradation (up to 4–5 levels) whenever necessary, allowing utmost control over particle-size distributions from fine to ultrafine. By choosing the right screening solution for their specific application, processors are able to assure the utmost quality, consistency, and performance of every batch of besan and maintain the efficiency and satisfaction of their customers.