Dehydrated garlic: cloves, flakes, slices, minced, granules and powder

Dehydrated garlic is garlic with the water taken out and nothing else changed. A draft national standard written with reference to ISO 5560 defines it as the product of drying sound garlic cloves without bleaching or precooking (Rwanda Standards Board, DRS 372).

Three sets of rules describe it. The international specification is ISO 5560:1997, Dehydrated garlic, which lists the main commercial forms in an annex and gives storage and transport recommendations in another (ASN summary of ISO 5560). Codex has a standard for dried or dehydrated garlic, CXS 347-2019, cited in a WTO notification of the East African draft standard hosted on the Spices Board India website. In the United States, the American Dehydrated Onion and Garlic Association (ADOGA) Official Standards and Methods, 15th edition, December 2022 sets named grades with sieve limits.

For customs it is a dried vegetable under HS 0712.90 (WTO notification). The US tariff narrows that to 0712.90.40, garlic, split into powder or flour and other (USITC Harmonized Tariff Schedule).

From largest to smallest: whole and split cloves, slices, flakes, chopped, minced, ground, granulated and powder. Below cloves and slices, every grade is defined by what may stay on one sieve and what may pass through another.

The names do not line up across standards. ADOGA's series starts at chopped and has no flake grade, while the ISO-based text has flakes and grits but no minced (ADOGA; Rwanda DRS 372). Whole cloves, slices and chips are therefore bought on a size written into the contract. Name the sieve, not just the grade.

Poorti's garlic line runs four cuts: flakes and cloves, whole and split; chopped and minced at 1–3 mm; granules at 0.1–1.0 mm; and powder at 100–120 mesh, all under HS 0712.90 (the garlic line). On the US scale, 100 to 120 mesh is an opening of 0.15 to 0.125 mm (LibreTexts).

There is none in the garlic. Garlic powder is one grade of dehydrated garlic, the smallest in the series, milled and sieved finer than granules (ADOGA).

What changes is how it behaves. Powder may carry an anti-caking agent: the ISO-based draft allows up to 2.0% in powdered garlic and otherwise no preservatives, colours or flavourings (Rwanda DRS 372). ADOGA lists granulated garlic with a suitable anti-caking agent as its own grade, and notes that granulated garlic may be a blend of granulated and agglomerated material to control bulk index (ADOGA).

Bulk index is the volume in millilitres of 100 g after tapping, and it matters to anyone filling jars by volume. ADOGA's guideline ranges are 120–140 for granulated, 120–150 for minced and 120–175 for chopped garlic, and it does not recommend setting bulk index for powders (ADOGA).

• Cloves and flakes: visible garlic in pickles, marinades, seasoning packs and retail blends.
• Chopped and minced: even flavour without visible pieces, in instant noodles, ground meat and dry soup mixes.
• Granules: free-flowing, for automated dosing and blending lines.
• Powder: dissolves completely, for sauces, dressings, condiments and coating systems.

The cloves are peeled, dried, then cut to flake, granule or powder (the garlic line). There is no precooking or bleaching step (Rwanda DRS 372).

A study in Drying Technology dried 5 mm garlic slices in air, under vacuum and under nitrogen, and found that drying rate rose with temperature (Rahman et al., 2009). The dried pieces are then milled and sieved to the grade ordered.

The finished colour should be characteristic of the variety, between white and pale cream, and practically free from scorched, toasted or baked particles (Rwanda DRS 372). ADOGA does not recommend added sulphites in dehydrated onion or garlic (ADOGA).

Because the enzyme that makes garlic's bite is destroyed by heat. Dry it too hot and the garlic loses allicin potential, however good it looks.

When raw garlic is crushed or chopped, the enzyme alliinase is released and turns alliin into allicin, a reaction complete within 10 to 60 seconds (Linus Pauling Institute, Oregon State University). The same source notes that heat can inactivate alliinase, that garlic powder is made from cloves dried at low temperature to prevent that, and that powder is measured by its allicin potential rather than by allicin itself.

In the drying study above, loss of allicin potential increased with drying temperature, and the authors concluded that drying below 50 °C should best retain it (Rahman et al., 2009). Standards measure pungency as volatile organic sulphur compounds, by ISO 5567; the ISO-based draft sets a minimum of 0.3% on a dry basis (Rwanda DRS 372).

Pungency depends on drying discipline, not the crop alone. If allicin retention matters to your product, say so in the enquiry and name the test.

About one fifth of the clove's weight. ADOGA's starting point for product development is that one part by weight of Fancy dehydrated garlic gives about the same flavour as five parts by weight of prepared fresh garlic of average strength (ADOGA).

Convert by weight, not by spoon. Each grade packs to a different density, which is why ADOGA publishes separate bulk index ranges for granulated, minced and chopped garlic (ADOGA). Treat the ratio as a starting point and adjust to taste, since pungency varies from lot to lot. The onion powder conversion guide works the same way for onion.

At least two years, if the pack keeps moisture out. ADOGA says packaging for dehydrated garlic should include a moisture barrier, and that under cool, dry storage proper packaging preserves quality for a minimum of two years (ADOGA).

Dry is the whole point. ADOGA sets a moisture maximum of 6.8% for dehydrated garlic products (ADOGA), and the ISO-based draft sets 8% and asks for food-grade containers that protect the product from light and the ingress of moisture (Rwanda DRS 372).

A university study stored industrially dehydrated garlic, onion, potato and carrot for 12 months: onion and garlic kept their fructooligosaccharides, and all samples stayed stable in polyphenol content and rehydration ability (Gamboa-Santos et al., 2012). Once a pack is opened, close it after each use and keep it away from steam and heat.

The grade by sieve size, the pungency you need, and the limits your market enforces. A grade name alone leaves too much open.

• Grade and size: name the standard (ADOGA, ISO 5560 or your own) and the sieve limits, or the mesh or flake size.
• Moisture ceiling: ADOGA sets 6.8% maximum; the ISO-based draft sets 8% (ADOGA; Rwanda DRS 372).
• Pungency: volatile organic sulphur compounds by ISO 5567, or allicin potential, and whether retention matters.
• Colour: white to pale cream, free from scorched particles.
• Sulphites: garlic's own sulphur compounds can read as sulphite in the common Monier-Williams test, and the US FDA requires any sulphiting agent used to be declared if sulphites exceed 10 ppm, so agree the test method (ADOGA).
• Anti-caking agent: whether one is allowed, which, and how much.
• Allergen statement: ADOGA recommends peanut allergen testing on every lot of internationally sourced onion and garlic, because peanut is often rotated in the same fields and harvest sacks are reused (ADOGA).
• Adulteration: starch is the most common adulterant in onion and garlic, checked with an iodine-starch test (ADOGA).
• Microbiology, heavy metals and pesticide residues: name your destination market's limits.
• Packing: moisture-barrier liner, net weight per pack, and the HS code your broker will enter, 0712.90.

Cut sizes on Poorti's garlic line are set to your order, and the full specification, with moisture, ash, microbiological limits, packing and container loading, is issued on request (the garlic line). Dehydrated garlic is rarely bought without onion; the dehydrated onion grades guide covers the other half of the order, and Source explains how the house buys by the container.