How to Unclump Garlic Powder (+4 tips to prevent clumping)

In this brief article, we will be discussing how to unclump garlic powder and why it clumps in the first place. Moreover, we will share with you six simple tips to prevent your garlic powder from clumping.

How to Unclump Garlic Powder?

Here are four easy ways to unclump garlic powder:

  • Place the opened container of clumped garlic powder in the microwave with a bowl of uncovered water. Microwave for about a minute to un-clump the powder.
  • Place the airtight container in hot water for a few minutes. Open the container and scrape the powder using a small utensil such as a spoon. Loosen the clumped powder as much as you can.
  • Place a teaspoon of uncooked rice or some dried beans into the container and shake vigorously.
  • Remove the clumped powder from the container, put it in a plastic bag, and smash it with a steak tenderizer.

By removing humidity from garlic powder, the water from the liquid can evaporate, leading to formation of a “hard cake” texture (1).

What Makes Garlic Powder clump/Harden?

What makes garlic powder clump is the water vapor present in the atmosphere. Garlic powder is an amorphous material and amorphous materials are also prone to caking and clumping but via different mechanisms. 

When amorphous materials are exposed to increasing RH, moisture is absorbed into the bulk of the matrix. Water plasticizes the amorphous solid (makes it more fluid) and may lower the glass transition temperature – which is the temperature range where the material changes from a rigid glassy material to a soft (but not melted) material – below the environmental temperature, which leads to a transformation from a glassy, solid-like state to a less viscous, rubbery, supercooled liquid state (2). The three common reasons why garlic powder forms clumps and becomes hard are:

Absorbs Moisture

The presence of water in low-moisture powdered food products and seasonings can cause stickiness, agglomeration, caking, clumping, crystallization of amorphous materials, and degradation of components, among more undesirable changes for both ingredient functionality and processing of powdered seasonings (3). 

Garlic powder begins to form clumps when it absorbs moisture. Moisture binds the granules of the powder together forming one solid clump. This process of easily absorbing moisture is known as ‘hygroscopy’.

Is Stored for Too Long

Most people tend to store spices for months and even years without realizing it! Even though aging spices are okay to use, the longer you store them, the higher the chances of them clumping.

That said, the average shelf-life of spices is about 2-3 years IF they are properly stored (more on that in the next reason!). Even a minor imperfection in storage temperature or packaging can adversely affect the lifespan of spices. According to the US Department of Agriculture, commercial garlic powder can be stored up to 3 to 4 years in the pantry (2). 

However, studies showed that after 4 months physicochemical changes occur that might degrade the product, depending on the drying method used for production, the storage conditions (temperature) and packaging material used. Color, humidity, acidity and flavor changes even at a temperature of -10 °C storage (3).

Is Stored Inappropriately 

After opening a packet of garlic powder, always keep it in a sealed/airtight jar or container. If you don’t, the garlic will absorb moisture from the surroundings and quickly become hard, especially in humid climates. Low-density polyethylene packages are more appropriate to store garlic powder (3).

Is Clumped Garlic Powder Safe to Eat?

Clumped garlic powder is not always safe to eat. Spices are known to contain compounds that are inhibitory to fungal growth and mycotoxin production. It has been reported that garlic, cinnamon bark and hops are able to inhibit the growth of toxigenic molds, whereas peppers, cloves, thyme and green tea inhibit toxin production only. However, if the moisture content of food is increased to levels above 13 to 16% during storage, mycotoxin formation can occur (6). 

In addition, a study showed that clumped garlic can be a host of fungus such as Fusarium proliferatum which produce mycotoxins that affect health negatively (5). The ingestion of mycotoxins may result in illness or even death. The effects of mycotoxins can manifest in a variety of ways, including neurologic impairment, liver, kidney, or heart failure. 

How To Prevent Garlic Powder from Clumping?

To prevent garlic powder from clumping, here are four simple tips:

Store in an Airtight Container

This applies to those buying garlic powder in packets or sachets. Always transfer the garlic powder to an airtight jar/container that has a proper seal. You can also purchase specially designed spice jars. 

Other airtight containers include:

  • Glass jars with tight-fitting lids, such as canning jars and recyclable food jars
  • Mylar bags
  • Kilner jars with rubber-sealed lids
  • Vacuum seal bags
  • Plastic airtight container (BPA-free)
  • Low density polyethylene containers are preferable (3)
  • Low temperatures storage is preferable and will extend shelf life (3)

Place Some Rice Grains in the Container

Place about a teaspoon of rice in the container along with the garlic powder. Rice is more hygroscopic than garlic powder and will pull in moisture more efficiently. Grains and husks can be used as natural desiccants, because they are made of starch and cellulose, which are highly hygroscopic, that is, they are very attracted to liquid and gas water molecules present in the environment. 

The presence of OH groups and the polar side of cellulose or starch makes the material naturally hydrophilic, so it has a high water-absorbing ability. This is due to the formation of hydrogen bonds of hydroxyl groups in the starch and cellulose chain with water molecules (4).

Store in a Cool, Dry Area

Store the garlic powder in a cabinet or a dark and dry spice cupboard away from the stove and direct sunlight.

Use Desiccants/Moisture Absorbers

You can also use food-safe moisture absorbers like silica gel or desiccants available in small sachets. If the garlic jar is opened frequently, these absorbers will ensure the product stays dry by readily absorbing moisture in the air.

Use Arrowroot Powder

Arrowroot powder is a natural, edible product that keeps garlic powder from absorbing excessive moisture and clumping. Only a teaspoon in a one-pint-sized jar is sufficient. An alternative to this product is cornstarch. Arrowroot contains mainly starch, which is highly hygroscopic and binds to water molecules (4).

Dehydrating the Powder

Simply pour the garlic powder onto a non-stick tray or parchment paper and cover with a net. Place in an oven under low heat. Cool to room temperature and store the powder in an airtight container.  


In this brief article, we answered the question of how to unclump garlic powder and also shared with you the reasons for clumping and six simple tips to prevent your garlic powder from clumping.

If you have any comments or questions, please let us know. 


  1. Voelker, Adrienne L., Abigail A. Sommer, and Lisa J. Mauer. Moisture sorption behaviors, water activity-temperature relationships, and physical stability traits of spices, herbs, and seasoning blends containing crystalline and amorphous ingredients. Food Res Int, 2020, 136,  109608.
  2. Food Safety and Inspection Service – USDA
  3. Madhu, B., Mudgal, V.D. & Champawat, P.S. Influence of the packaging material and storage temperature on the shelf life of garlic powder. J Food Sci Technol, 2021, 58, 4333–4343.
  4. Warsiki, E., et al. Isotherm moisture sorption of composite desiccant made from rice husk biomass. IOP Conf. Ser. Earth Environ. Sci., 2021, 749.
  5. Boonzaaijer, G., et al. An exploratory investigation of several mycotoxins and their natural occurrence in flavour ingredients and spices, using a multi-mycotoxin LC-MS/MS method. World Mycotoxin J, 2008, 1, 167-174.  
  6. Bullerman, Lloyd B., Lisa L. Schroeder, and Kun-Young Park. Formation and control of mycotoxins in food. J Food Protect, 1984, 47, 637-646.