Understanding the Physical Properties and Grading System of Cashew Kernels

Not all cashew kernels are equal – and in the global cashew trade, that inequality is precisely measured. Every kernel that leaves a processing facility carries a grade code that tells buyers exactly what they are getting: its size, color, shape, and freedom from defects. This grading system is the backbone of cashew commerce, ensuring that a W180 kernel from India meets the same standard as one processed in Vietnam or Brazil. Understanding how these grades work – and what physical properties they reflect – matters to everyone from post-harvest processors to food manufacturers sourcing raw ingredients.

The four pillars of cashew kernel grading 🔗

Cashew kernel quality is evaluated on four core physical properties: size, color, shape, and the presence or absence of defects. Each of these factors influences a kernel’s commercial grade, and together they determine the price it commands in both domestic and export markets. Grading is always carried out in a fixed sequence – color is assessed first, followed by shape, and then size. This systematic approach ensures consistency across production batches and trading partners worldwide.

The primary division: wholes and brokens 🔗

The most fundamental classification in cashew grading separates kernels into two broad categories: whole kernels and broken kernels. This distinction forms the structural foundation of the entire system.

Whole kernels 🔗

According to the Association of Food Industries (AFI) standards, a kernel is classified as whole if it retains the characteristic kidney shape of a cashew and not more than one-eighth (1/8) of the kernel has been broken off. The UNECE Standard DDP-17 adds that the presence of a small hole at the proximal end or a central crack is not considered a defect. Whole kernels are the most valued category and command the highest prices in the market.

Broken kernels 🔗

Broken kernels are those where one-eighth or more of the original kernel has broken off during processing. They are further divided into sub-categories based on their shape and size. As per AFI classification, broken kernels are graded into:

• Butts (B): Kernels broken crosswise, retaining between 3/8 and 7/8 of the whole kernel, with the cotyledons still naturally attached.
• Splits (S): Kernels split lengthwise into halves, with not more than 1/8 of the cotyledon broken off.
• Large White Pieces (LWP) and Small White Pieces (SWP): Uniform pieces of varying sizes, used in granola, protein bars, sauces, and food coatings.
• Baby Bits (BB): Tiny cashew fragments suited for industrial processing and cashew-based pastes.

Broken kernels retain full nutritional and flavor value. Food manufacturers producing cashew butter, baked goods, and confectionery products actively prefer broken grades for their cost efficiency, since intact visual appearance is not a requirement in these applications.

Size classification of whole kernels 🔗

Within the whole kernel category, size is expressed as a count per pound – the number of kernels present in one pound (approximately 453.6 g) of cashews. The lower the count number, the larger and more premium the kernel. This straightforward logic is the most universally applied principle in cashew grading. The standard size designations used in international trade are:

W180 – the king of cashews 🔗

W180 is known as the “King of Cashews” and represents the largest whole kernel grade. With approximately 140-180 kernels per pound, each nut measures roughly 22-26 mm in length. This grade is considered the most premium due to its size, visual appeal, and the lower processing yields required to produce it. W180 kernels typically command prices 20-30% higher than W320 grades, a premium that reflects both rarity and the higher skill required during processing. They are the preferred choice for high-end retail packaging, premium snack products, luxury gifting, and gourmet desserts.

W210 – jumbo grade 🔗

W210 kernels contain approximately 181-210 kernels per pound and are commonly referred to as “Jumbo” cashews. They are large, premium cashews suitable for luxury products and high-end confectionery, offering excellent quality at a slightly more accessible price point than W180.

W240 – the premium all-rounder 🔗

With approximately 220-240 kernels per pound, W240 is the perfect all-rounder for food service and fine foods. It is widely used in both premium retail packs and food service applications, striking a strong balance between size, quality, and price.

W320 – the most traded grade globally 🔗

W320 is the most popular and widely traded grade in the global cashew market. Containing 300-320 kernels per pound, these mid-sized kernels measure around 15-18 mm and offer a practical balance between affordability and versatility. They are used extensively in snack mixes, salads, baking, cashew butter, and food service applications. Their consistent availability and competitive pricing make them the default choice for bulk buyers and food manufacturers.

W450 – small but commercially significant 🔗

W450 kernels, containing 400-450 pieces per pound, are the smallest of the standard whole kernel grades. They maintain good quality and are ideal for processed products such as cashew milk, mixed nut products, and food industry raw material applications where kernel size is less important than cost-effectiveness.

Color classification 🔗

Color is the first parameter assessed during grading, and it plays a decisive role in determining which quality tier a batch belongs to. Cashew kernels are graded into three color categories: white (W), scorched (S), and dessert (D), each of which applies to both whole and broken grades.

White wholes (W) 🔗

White whole kernels display a pale ivory, white, or light ash color, indicating proper shelling, blanching, and drying. First Quality Fancy kernels under AFI standards must have a uniform color that is white, light yellow, or pale ivory. These are the highest-value kernels and are graded W followed by their size code – for example, WW180 denotes a white whole kernel of size 180.

Scorched wholes (SW) 🔗

Scorched kernels develop a slight brown to amber color due to prolonged exposure to heat during roasting or drying. Under CEPC standards, scorched wholes show a slight brown color resulting from longer roasting, but they retain the same shape, size, and nutritional profile as white kernels. They are widely used for further roasting, coating, and value-added processing. Scorched wholes are also sub-graded by size – SW180, SW240, SW320, and so on.

Dessert wholes (DW) 🔗

Dessert wholes are kernels with deep scorching, heavy discoloration, brown or blue spots, or significant blemishes. Dessert wholes may be slightly shriveled, immature, or brown-speckled on the surface, provided not more than 60% of the kernels are affected. While unsuitable for premium retail, they are used in confectionery coatings, flavored cashew products, and certain industrial food applications.

Key defects and quality tolerances 🔗

International standards establish specific tolerance limits for defects found within each grade. Under UNECE Standard DDP-17, cashew kernels must be completely free from infestation or living pests, molds, insect damage, rotting, rancidity, and adhering testa. The defect tolerance framework includes:

• Mould, rancidity, and decay: Permitted at 0.5% by weight for Extra Class, and up to 1% for Class I and II.
• Damage by pests: Maximum 0.5% (Extra Class) to 1% (Class II). Living pests are never permitted in any grade.
• Adhering testa: Residual seed coat on the kernel surface, tolerated up to 3% for Extra Class and 5% for Class II.
• Superficial damage: Deep knife cuts or abrasions on the kernel surface, permitted at 1% for Extra Class up to 5% for Class II.
• Broken kernels in whole grades: Must not exceed 10% by weight across all classes.
• Foreign matter: Shell fragments, loose testa, and dust must not exceed 0.1% by weight.

Premium grades such as W180 have very tight tolerance limits, while lower grades permit marginally higher defect levels, provided food safety is not compromised. Under CEPC standards, the allowable limit for next lower grade content is 5% for white wholes and 7.5% for scorched and dessert wholes.

The 27 conventional international grades 🔗

Combining color, shape, and size produces a matrix of commercially recognized grades. A white whole kernel of size 180 is designated WW180, while a scorched whole of size 240 is SW240. A combination of these parameters yields 27 conventional international grades, though additional grades exist depending on country of origin and specific market requirements. The Global Cashew Council maintains technical documentation of these standards, while bodies like the Cashew Export Promotion Council of India (CEPC) and Vietnam Cashew Association (VINACAS) provide region-specific specifications used in export contracts.

Why grading matters beyond pricing 🔗

The grading system serves a purpose well beyond assigning price tiers. It creates a shared technical language between buyers and sellers across different countries, ensures traceability through the post-harvest supply chain, and supports food safety compliance by enforcing defect tolerance limits. For processors, accurate grading directly improves profitability – segregating production into distinct grades rather than selling as a mixed lot can significantly increase revenue per unit. For food manufacturers, it ensures consistent raw material quality, which in turn affects final product texture, appearance, and shelf life.

What do you think? Given that W320 is the most globally traded grade while W180 fetches the highest price, how should a cashew processor decide which grades to prioritize in their production mix? And as quality inspection increasingly shifts toward automated optical sorting, do you think the current 27-grade classification system is detailed enough for modern food industry demands?

References

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4. https://cosmos-color-sorter.com/cashew-classification/
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