Makhana, also known as fox nut, gorgon nut or phool makhana, has become an important ingredient for roasted snacks, fasting foods, breakfast products, trail mixes and functional food formulations. However, not all makhana seeds deliver the same popping performance, yield, appearance or commercial value.
For processors, understanding makhana seed grades is essential before purchasing raw material. Seed size affects heating uniformity, popping expansion, finished-kernel appearance and the quantity of broken or partially popped pieces. A well-defined grading system also helps processors negotiate with suppliers, select suitable machinery and maintain batch-to-batch consistency.
Makhana seeds are generally graded before roasting and popping according to size. After popping, the kernels may be classified further on the basis of diameter, colour, expansion, surface appearance and defects. This guide explains the major makhana seed sizes, traditional grading terms, practical quality parameters and a procurement checklist for processors in India.
What Are Makhana Seeds?
Makhana is the seed of the aquatic plant Euryale ferox Salisb. Of Nymphaeaceae family (water lily). Euryale is an aquatic herb found along the edges of ponds, marsh, and lakes. The most important makhana production areas in India are in the state of Bihar, mainly in the Mithila region.
Raw seed has a hard dark exterior shell. Raw seed is generally a rounded shape and is normally 515mm in diameter although this will vary based on maturity and growing conditions. The white edible product that is generally bought in shops is not raw seed. It is the expanded kernel that is produced through the processes of drying, roasting, and popping. Makhana processing usually includes:
- Harvesting of mature seeds.
- Washing and cleaning.
- Sun-drying or controlled drying.
- Size grading of dried seeds.
- Roasting or pre-heating.
- Tempering.
- Popping.
- Polishing and cleaning.
- Grading of popped kernels.
- Packaging.
Size grading before roasting is important because seeds of different diameters require different heating conditions. If small and large seeds are processed together, the smaller seeds may burn or overheat while the larger seeds remain underheated and fail to pop properly.
Why Seed Grading Matters
Makhana grading is not merely a trading practice. It directly influences process efficiency and finished-product quality.
1. Better heating uniformity
Uniform seeds absorb heat at a more consistent rate. This supports better control over roasting and popping. In mixed-size batches, each seed may require a different heating time, increasing the risk of under-processing or burning.
2. Improved popping yield
Larger, mature and well-dried seeds generally have better potential to produce larger popped kernels. However, size alone does not guarantee quality. Internal moisture, shell strength, seed maturity and storage conditions also affect popping performance.
3. Consistent product appearance
Premium snack brands usually need uniform, bright and fully expanded kernels. Grading helps processors create packs with a consistent visual appearance and reduces the presence of small, dark or irregular pieces.
4. Reduced breakage and wastage
A properly graded batch can be processed using more suitable heating parameters. This may reduce breakage, excessive charring and the quantity of unpopped seeds.
5. Easier product positioning
Different grades can be assigned to different products. Smaller grades may be suitable for flour, powder, namkeen blends or value-oriented snacks. Larger grades are generally preferred for premium roasted products, gifting packs and export-oriented applications.
Raw Makhana Seed Size Grades
After drying, raw makhana seeds may be passed through sieves or mechanical graders. Industry and processing references commonly describe raw seeds in five to seven size categories. One commonly cited classification includes the following bands:
|
Raw seed size |
Typical processing relevance |
|
3–5 mm |
Small seed; suitable for lower-value applications or blending |
|
5–7 mm |
Small-to-medium seed; may be used in standard processing |
| 7–9 mm |
Medium seed; suitable for regular snack production |
|
9–11 mm |
Medium-to-large seed; useful for improved popping quality |
| 11–13 mm |
Large seed; generally preferred for better kernel expansion |
|
13–15 mm |
Extra-large seed; premium raw material category |
| Above 15 mm |
Jumbo or special lots, subject to supplier specification |
These size bands are viewing from a procurement specification perspective rather than a legal trade grades perspective. A supplier may operate to different sieve openings, to different terminology or to different measuring methods. Processor must always clarify whether the size quoted relates to using current US legislation, what grade to the sweet is the proposed change for every other nationality, what sort of legal grade will the proposed change be.
The size reduction done on raw seed is generally a sieve, perforated plate or a mechanical seed graders. The grading machine gives the size classification of the seed before roasting. This enables the processor to apply the different heating cycles for the different sizes of seed.
Understanding Suta Grading
“Suta” is a traditional trade term used in the makhana industry to describe the size of popped kernels. In general, a higher Suta category indicates a larger popped kernel. However, terminology can vary between traders, regions and suppliers.
Some commercial suppliers describe categories such as 4 Suta, 5 Suta, 6 Suta, 6+ Suta and 7 Suta. Approximate commercial ranges may look like this:
| Commercial category | Approximate popped diameter | Common applications |
| 4 Suta | 12–15 mm | Economy snacks, institutional use and grinding |
| 4+ Suta | 14–16 mm | Standard and mid-tier snack products |
| 5 Suta | 15–18 mm | Mainstream roasted makhana and retail packs |
| 5+ Suta | 16–19 mm | Premium retail and quality-focused brands |
| 6 Suta | 18–21 mm | Premium snacks, gifting and modern retail |
| 6+ Suta | 19–22 mm | Super-premium and export-oriented products |
| 7 Suta | 21 mm and above | Jumbo, luxury and selective premium lots |
The size ranges above are indicative. A processor should not assume that every supplier uses the same definition for a particular Suta grade. Before placing an order, the buyer should request a sample, diameter range, tolerance level and percentage distribution.
Some traders may also use different Suta numbering systems. This is why the phrase “6 Suta” should never be accepted as a complete specification on its own. The purchase document should include the actual size in millimetres.
Lawa, Murra and Thurri
Apart from size-based classifications, the popped product is also described using traditional terms such as lawa, murra, rasgulla, samundha and thurri. Usage may vary across producing regions, but these terms generally refer to the degree of expansion and visual quality.
Lawa or rasgulla
Lawa is typically used for fully expanded, light-coloured and swollen makhana. It usually has a better appearance and a crisp texture. Premium snack packs commonly require a high proportion of lawa.
Murra or samundha
Murra or samundha may refer to smaller, irregular or less-expanded pieces, depending on the local classification system. These pieces may still be edible and useful in mixtures, but they generally command a lower value than fully expanded kernels.
Thurri
Thurri is generally associated with semi-popped, hard, reddish or irregular kernels. It has lower visual appeal and may not be suitable for premium whole-kernel packs. However, it can be used in powder, flour, blended snacks or other value-added applications.
A processor should ask the supplier whether the quoted grade refers to size, expansion quality or both. A large kernel with poor expansion is not equivalent to a large, fully puffed and clean kernel.
Key Quality Parameters
Size is only one part of makhana quality. A reliable procurement specification should include several additional parameters.
Colour
Good-quality popped makhana is usually white to creamy white. Excessive reddish, brown, grey or black colour may indicate overheating, burning, poor storage or inadequate cleaning.
A small amount of natural reddish spotting may occur, but the acceptable level should be agreed in advance. Premium retail products generally require a cleaner and more uniform appearance.
Expansion
Processors should distinguish between fully expanded, partially popped and unpopped material. Fully expanded kernels normally provide better volume, texture and consumer appeal.
A supplier should disclose the percentage of:
- Fully expanded kernels.
- Semi-popped kernels.
- Unpopped seeds.
- Broken pieces.
- Burnt or dark pieces.
Uniformity
A batch containing similar-sized pieces is easier to flavour, roast, fill and pack. Excessive variation may result in uneven seasoning and inconsistent eating quality.
Moisture
Moisture affects crispness, shelf life, microbial stability and storage behaviour. Raw seeds that are not adequately dried may develop mould or deteriorate during storage. Popped makhana can also absorb atmospheric moisture quickly, causing loss of crispness.
The processor should define moisture limits according to the product format, packaging system and expected shelf life. Moisture should be checked using a calibrated method rather than judged only by touch.
Cleanliness
Raw and popped makhana should be free from stones, sand, plant debris, insects, foreign matter and visible contamination. Cleaning and sieving are especially important when the raw material is sourced from informal or fragmented supply chains.
Odour and taste
Makhana should have a clean, mild and characteristic odour. Musty, rancid, smoky, chemical or mouldy odours indicate possible quality problems.
Breakage
Broken kernels may be used for flour powder bars, coated products or mixes in snacks. Whole-kernel snack packs need to have a low percentage of broken material. The agreed limit should be shown on the purchase specification.
Choosing the Right Makhana Seed Grades for Each Product
The best makhana grade depends on the end use rather than simply the largest available size.
| Product type | Suitable material |
| Premium roasted makhana | Large, fully expanded and uniform kernels |
| Flavoured retail snack | Medium-to-large whole kernels with good surface quality |
| Institutional snack mixes | Standard or mid-range grades |
| Makhana flour | Small, broken, irregular or lower visual grades |
| Energy bars and clusters | Broken pieces and mixed sizes, depending on formulation |
| Namkeen blends | Medium grades and controlled broken content |
| Fasting food mixes | Clean, light-coloured and low-defect kernels |
| Premium gifting packs | Jumbo or extra-large, hand-sorted kernels |
| Export products | Uniform, clean, well-packed and specification-compliant grades |
Using premium jumbo kernels in a powdered product may increase raw-material cost without improving the final product. Conversely, using excessive broken material in a premium whole-kernel pouch can reduce consumer perception and retail value.
Makhana Seed Grading Checklist
Processors can use the following checklist when evaluating a supplier or approving a lot.
Supplier and traceability
- Supplier name and location.
- Production region.
- Harvest or processing season.
- Batch or lot number.
- Raw or popped product status.
- Processing date and packing date.
- Storage conditions.
- Availability of a certificate of analysis.
Size specification
- Raw seed size in millimetres.
- Popped kernel size in millimetres.
- Suta category, if applicable.
- Minimum and maximum diameter.
- Percentage distribution within the declared size band.
- Percentage of undersize and oversize material.
Appearance
- White, creamy-white or other agreed colour.
- Percentage of reddish spots.
- Percentage of dark or burnt pieces.
- Percentage of fully expanded kernels.
- Percentage of semi-popped kernels.
- Percentage of unpopped seeds.
- Percentage of broken pieces.
Safety and hygiene
- Foreign matter.
- Insect damage.
- Mould or fungal growth.
- Unusual odour.
- Evidence of infestation.
- Cleaning and sorting controls.
- Packaging integrity.
Processing performance
- Popping yield.
- Expansion ratio.
- Breakage after roasting.
- Required heating profile.
- Flavour absorption.
- Crispness after packaging.
- Behaviour during storage.
Documentation
- Product specification sheet.
- Test report or certificate of analysis.
- Food business licence details, where applicable.
- Packaging and labelling information.
- Agreed rejection and replacement terms.
A sample approval should always precede bulk procurement. The processor should test the sample using the same roasting, popping and seasoning conditions planned for commercial production.
How Processors Can Improve Grade Control
A systematic quality-control plan should be implemented for the makhana, based on the raw seed at first stage, pre-popping stage of the matured seed, and finished packed product at final stage. On receiving, check raw seed for size distrubution moisture foreign matter and damage in the seed. During processing, record heating time, roasting temperature, tempering time and popping yield. After popping, measure diameter of the kernel expansion colour, and broken, unpopped.
Digital records can enable the identification of performance of suppliers over season. Instead of accepting or approving a supplier based on an attractive sample, the processors may need to record several lots over the season. While seasonal variation, periods in storage and region of origin, may result seed performance.
It is also useful to create internal grade names, such as:
- Standard snack grade.
- Premium whole-kernel grade.
- Jumbo gifting grade.
- Processing and flour grade.
Each internal grade should have measurable limits. For example, “premium whole-kernel grade” may require a minimum average diameter, a maximum broken percentage, and a defined limit for dark pieces. This makes the specification easier for procurement, production and quality teams to follow.
Conclusion
A makhana seed grading system is a very useful tool to increase processing consistency, manage cost and pick the correct raw material for each product. The processor should consider size and functional quality attributes such as moisture, expansion, colour, breakage, cleanliness, and popping yield. The most secure way of acquiring quality is to require measurable millimeter specifications, regard Suta as a trade guideline (not definitive standard), require sample approval before bulk purchase, and use separate grades for premium snacks, standard products and value-added applications. A carefully managed grading system can result in more efficient production and more consistent makhana products delivered to the market.
Frequently Asked Questions
What are the main makhana seed grades?
Makhan are sorted into 57 size categories, usually varying from 3 to 15 mm.
What does Suta mean in makhana?
Suta is a generic name for traditional trade name for prick keptmakhana kernel size.
Which makhana grade is best for roasted snacks?
Medium to large size and relatively consistent popped kernel (56 Suta) are recommended for roasted snacks.
Is larger makhana always better?
No; the parameters of quality are expansion colour crunch and moisture.7 Size is not a quality parameter!
What is the difference between lawa and thurri?
Lawa is completely popped, light kernels; thurri is soom semi-popped harder irregular material.
How should processors check a makhana sample?
Check raw size moisture odour; then sample popping yield, expansion, colour, and breakage.
What should be included in a makhana purchase specification?
Add raw/popped status, length (mm) Suta moisture colour breakage, foreign matter and packaging.