Technical Reference · Grading
Makhana Grading System —
The Complete Suta Reference
The Suta system is the standard method for grading raw makhana (fox nuts) in India. This reference covers what each grade means, how grades are measured, export vs domestic specifications, quality parameters, and the most common mistakes buyers make when sourcing.
What Is the Makhana Grading System?
Direct answer: The makhana grading system classifies raw fox nuts by kernel diameter using a unit called Suta, where one Suta equals approximately 1/8th of an inch (~3.175mm). Grades range from 4 Suta (smallest commercial grade, 8–10mm) to 6+ Suta (largest export grade, 16–21mm). Higher Suta number = larger kernel = higher market value.
The Suta system originated as a traditional measurement used by makhana cultivators and traders in the Mithilanchal region of North Bihar — the primary cultivation zone for Euryale ferox (fox nuts) in India. It remains the dominant grading standard across domestic and export markets.
Grading happens at source — at the threshing and sorting stage after harvest. Kernels are passed through sizing sieves calibrated to Suta specifications. Manual inspection follows for whiteness, breakage, and surface integrity. Each grade commands a different price and is suited to a different application.
Why Grade Matters for B2B Buyers
Grade is not just a size specification — it determines moisture capacity, expansion during roasting, visual appearance in the final product, and export compliance. A buyer who purchases 5 Suta expecting 6 Suta visual quality will face product failures at retail. A buyer who pays for 6+ Suta to use in grinding is wasting premium material on a function that 4 Suta handles equally well.
Grade Specifications — 4 Suta to 6+ Suta
At a glance: 4 Suta (8–10mm) is standard manufacturing grade. 5 Suta (10–13mm) is mainstream snacking. 6 Suta (13–16mm) is premium retail. 6+ Suta (16–21mm) is export grade. Each grade has distinct moisture limits and quality parameters.
| Grade |
Diameter |
Moisture Max |
Breakage at Dispatch |
Primary Application |
Typical Buyer |
| 4 Suta |
8–10mm |
<8% |
<5% |
Manufacturing, grinding, flour, nutraceuticals |
FMCG manufacturers, supplement brands |
| 5 Suta |
10–13mm |
<7% |
<4% |
Mainstream roasted snacking, mid-range retail |
Snack brands, private label, distributors |
| 6 Suta |
13–16mm |
<6% |
<3% |
Premium retail, flavoured products, gifting |
Premium snack brands, retail chains |
| 6+ Suta |
16–21mm |
<5% |
<3% |
Export, luxury retail, HoReCa, institutional |
Exporters, UAE/UK/US buyers, hotels |
| Custom Mix |
Bespoke |
Per spec |
Per spec |
Proprietary blends, specific brand requirements |
Brands with defined grade formulations |
All specifications are at point of dispatch from Bihar. Transit conditions affect moisture. Export buyers should specify moisture at destination if different from dispatch spec.
Export Grade vs Domestic Grade — Key Differences
Direct answer: Export-grade makhana (primarily 6+ Suta) requires moisture below 5%, NABL-tested lab reports for heavy metals and mycotoxins, and strict breakage limits. Domestic-grade makhana (4–5 Suta) has more relaxed moisture specs and does not always require third-party lab documentation.
Export Grade
6+ Suta · International Markets
- Moisture below 5% mandatory
- NABL lab report per batch
- Heavy metals tested (Pb, Cd, Hg, As)
- Mycotoxin panel (Aflatoxin B1/B2/G1/G2)
- US FDA / GCC compliant
- Breakage below 3% at dispatch
- Origin documentation required
- Strict whiteness and visual uniformity
Domestic Grade
4–5 Suta · India Markets
- Moisture 7–8% acceptable
- Lab reports optional for most buyers
- FSSAI compliance sufficient
- Breakage below 5% acceptable
- Visual variation tolerated
- Lower price per kg
- Faster availability, wider supply base
- Suitable for processing and manufacturing
The critical difference is not just size but documentation. Export buyers require a verifiable chain — NABL lab report, FSSAI certificate, and origin documentation — before any customs clearance. Domestic buyers rarely demand this level of documentation but should, especially for food products that reach end consumers.
Quality Parameters Beyond Grade
Grade (Suta) defines size. But size alone does not define quality. Buyers who source only on grade specification without verifying these parameters routinely receive sub-standard material.
| Parameter |
What It Measures |
Why It Matters |
Acceptable Range |
| Moisture Content |
Water activity in the kernel |
High moisture = weight gain fraud + shelf life reduction + mycotoxin risk |
<5% export · <8% domestic |
| Whiteness Index |
Visual brightness of kernel surface |
Consumer preference + premium pricing. Off-white indicates poor drying or age |
Bright white to cream — no grey or yellow tinge |
| Breakage % |
Proportion of broken or cracked kernels |
Affects visual quality, weight, and expansion during roasting |
<3% export · <5% domestic |
| Aflatoxin Level |
Mycotoxin contamination from fungal growth |
Regulatory compliance. EU and US have strict limits. Health risk if exceeded |
<10 ppb (FSSAI) · <4 ppb (EU) |
| Heavy Metals |
Pb, Cd, Hg, As from soil or water |
Export rejection and health liability. Must be tested, not assumed safe |
Per FSSAI / importing country limits |
| Expansion Ratio |
Size increase when roasted |
Determines yield for roasted snack manufacturers. Varies by grade and moisture |
Typically 2–3x for export grade |
When NOT to Use 6+ Suta — Important Buyer Guidance
Key insight: Larger grade is not always better. 6+ Suta costs significantly more per kg. If your application does not require large kernel size, you are paying a premium for a specification that adds no value to your product.
Do NOT use 6+ Suta for these applications
Grinding and flour production — Kernel size is irrelevant after grinding. 4 Suta delivers identical nutritional output at lower cost.
Heavily flavoured coatings — Thick flavouring masks visual quality differences between grades. 5 Suta is sufficient and more economical.
Crushed or broken product formats — If the kernel is intentionally broken in processing, paying for large kernel size is waste.
Institutional bulk catering — Where presentation is secondary to volume and cost, 5 Suta typically offers better value without quality compromise.
Very small trial batches — 6+ Suta supply is more limited. For initial product development, 5 or 6 Suta is more readily available and allows faster iteration.
The right grade is determined by end product, not by the assumption that bigger is better. A well-formulated 5 Suta roasted snack will outperform a poorly processed 6+ Suta product every time. Grade is an input specification, not a quality guarantee.
Common Buyer Mistakes in Makhana Grading
These mistakes are observed repeatedly across first-time and repeat buyers. Understanding them before purchasing protects quality, cost, and supply chain integrity.
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01
Buying on price without specifying grade
When a buyer requests "makhana at the best price" without specifying Suta, suppliers will often ship mixed-grade material — whatever is most available. Mixed-grade lots contain a proportion of lower grades that pull down average quality and create inconsistency in the final product. Always specify grade before discussing price.
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02
Assuming 6 Suta is automatically export-ready
Grade alone does not determine export compliance. A 6 Suta batch with 8% moisture or elevated aflatoxin levels fails export standards regardless of size. Export readiness requires: correct grade + correct moisture + NABL lab clearance. Do not assume — request documentation.
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03
Not requesting NABL lab reports
Heavy metals and mycotoxins are invisible. A batch can look perfect and be contaminated. Buyers who skip lab reports are accepting undisclosed risk. For any order destined for export or food manufacturing, NABL documentation is non-negotiable.
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04
Conflating origin with quality
Not all makhana from Bihar is Mithilanchal origin. Makhana is also cultivated in other states and imported from Bangladesh and China into some supply chains. "Bihar makhana" does not automatically mean Mithilanchal wetlands sourcing. Buyers should verify origin at district level — Darbhanga, Madhubani, Saharsa, Sitamarhi.
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05
Measuring quality only at delivery, not at dispatch
Moisture increases during transit if packaging is inadequate. A batch dispatched at 5% moisture can arrive at 7-8% if packaging fails. Quality disputes are easier to resolve when documented at dispatch — weight, moisture, breakage — not only at destination. Always request dispatch documentation with every commercial order.
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06
Grade mixing in the supply chain
Some intermediary traders blend smaller kernels into higher-grade lots to increase volume. Visual inspection of a sample will not always detect this. The safest protection is sourcing directly from a verified supplier with grade-specific documentation per batch, not spot-market purchases from undisclosed sources.
Frequently Asked Questions
What does Suta mean in makhana grading?
Suta is a traditional Indian unit of measurement equal to approximately 1/8th of an inch (3.175mm). In makhana grading, it refers to the diameter of the processed kernel. A 4 Suta kernel measures approximately 8–10mm. A 6+ Suta kernel measures 16–21mm. The higher the Suta number, the larger the kernel.
What is 6+ Suta makhana used for?
6+ Suta makhana is the largest commercially available grade, used primarily for export to international markets (UAE, UK, USA, Singapore), premium retail products, luxury gifting, and HoReCa (hotel/restaurant/catering) applications. It requires moisture below 5% and NABL-verified lab reports for export compliance.
Is larger Suta grade always better quality?
No. Larger grade commands higher price but is not always appropriate. For grinding, flour production, or heavily flavoured products, smaller grades are functionally equivalent and more economical. The correct grade depends on the end application, not on the assumption that bigger is better.
How do I verify makhana grade when purchasing?
Request a grade certificate and NABL lab report per batch. Inspect a representative sample before accepting full shipment. Document moisture, weight, and breakage at dispatch — not only at destination. For large commercial orders, request a third-party inspection at the supplier's facility before dispatch.
What is the difference between 5 Suta and 6 Suta makhana?
5 Suta kernels measure approximately 10–13mm and are suited for mainstream snacking and mid-range retail products. 6 Suta kernels measure 13–16mm and are used for premium retail, flavoured applications, and branded products where visual quality matters. 6 Suta commands a higher price but is not export-grade — that designation requires 6+ Suta with additional quality documentation.