Onion powder


Onion is a vegetable that grows under the soil while its leafy greens grow above the soil. Onion grows as a lump of layered vegetable that is called a bulb of an onion. It has close relations to chive, leek, scallion, and garlic which all grow in the same manner. They are naturally occurring in 3 different color varieties, Yellow or brown onions, Red or purple onions, and white onions. You can harvest onions and eat them at any stage of their growth, even immature age. However, large mature onions are the preferred choice.

Onion composition and usage

Onions comprise almost 90% water, and the rest of the elements include fiber, protein, carbohydrates, etc. The onions give a savory flavor to the recipes that include them, which is what makes it special, and that’s why its use is so common. Onions can be chopped and used in a variety of dishes and recipes. However, there are recipes like onion chutney, creamed onions, and French onion soup, where onion itself is the main ingredient. You can purchase fresh onions from the market, but onions are also available in pickled, caramelized, frozen, and canned forms. You can also purchase onions in their processed and dehydrated forms as onion powder, granulated, minced, ring, kibbled, and more. Onions are also relished when pickled in vinegar. 

Why use onion powder?

Let’s agree that we all love to dehydrate foods. That is an amazing way to preserve different types of food. Preservation reduces wastage. It allows usage through the year when there may be a short supply, like, e.g., winters. Some dishes taste better with onion powder, and you can also use the onion powder as a seasoning or in dishes where you need dry herbs, spices, and vegetables. The onion powder gives a savory, sweet taste adding the perfect pop of flavor. They are very versatile when it comes to using them as a dry powder and is one of our favorite seasonings. When processed properly, it can last over a year in storage. Cleary the pros outweigh the cons if any. 

onion powder
Onion powder @Amazon

Materials and Equipment’s: Keep these things ready

  • Onions: Get yourself a large number of onions, large enough to make enough powder. Remember, onions are 90% water. 
  • Food Dehydrator: You can use either of the two. Either use an oven or use a dehydrator for drying out the onion pieces. Ideally, we would recommend a dehydrator as our first choice as it almost clearly mimics the natural drying process. An oven will heat and also slightly cook the onions, thus taking away some of the nutrients and taste. 
  • Processor: You will need a good food processor, grinder, or blender to complete the job and turn the dehydrated onion into a fine powder.
  • Storage: Any airtight jar or container would serve the purpose, e.g. such as a mason jar with a lid. 

Peeling and cutting the onion

The process will depend on the type of onions you have. If you have purchased them from the supermarket, there is not much cleaning required. You have just to peel them and cut them into the desired shape. However, if you have fresh onions from the garden, it’s a whole plant with the leafy greens and roots attached. Wash the entire plant to clean it thoroughly of any dirt and mud. Cut off the onion bulb, which has the roots attached. Cut off the roots and peel to remove the onion’s first outer layer, which is papery skin. 

Slicing the onion

This is usually the difficult part, not just because of the amount of work but also because onions will make you cry, and you have a ton of them already. Have a slice of lime or lemon ready just in case. To reduce the tears from cutting onions, you can bite into lemon or lime to reduce their intensity. It’s a handy tip that will get you through this job. 

Now is the time to slice them. Remember that they will undergo dehydration, which essentially means all the moisture from them will be taken out. To make dehydrations faster, you must make a lot of thin slices. The thinner, the better. For this purpose, you can use a food processor to do the job in a really quick time. Another alternative is to use a box slicer for the job, which is tedious but still ok. You do not want to individually slice all the onions as it’s going to take an extraordinarily long time to do it. The slices must be consistent for an even amount of drying, and try to get them 1/8th on an inch thick for best and quickest results. Follow the same slicing style for even the green onion stems if you are planning to use them. 

Irrespective of how you dehydrate them, ensure they are never piled up. Instead, lay them side by side for the best results.

Dehydrating the onion

The onions will need to be utterly dehydrated before they can be turned into powder. The most important of the steps in the entire process. If it is done well, the onion powder will taste awesome and will not lose much of its flavor in the processing. However, suppose the dehydration is not done correctly. In that case, it will lead to raw onion flavor due to some moisture content remaining, or the onions will get damaged, affecting the taste and flavor. To check if the onions have been dehydrated properly, squeeze them between your fingers, and you should see them crumble. Also, when you try to bend the slices, they should snap. 

Drying naturally:

You can dehydrate onions naturally, as has been done for thousands of years. Just leave them on thin screens to dry naturally. As the onions slowly age, they will lose the water content naturally by evaporation. Ideally, place them in a warm or hot environment with a constant airflow over them to speed up the process. Toss them every morning, afternoon, and evening to ensure they dry off evenly. This process will take 3-6 days, depending on the heat and how thick the onion slices are. This process will retain the maximum taste and flavor but is long and will take a lot of effort. Do it only if you do not have a dehydrator or an oven. 

Food dehydrator:

This is a machine that is relatively inexpensive and easily available. You can plan to invest in one as it will serve you for drying out other food items too e.g., while making garlic powder. This automatic device pumps warm air continuously over the vegetable places inside it to dehydrate them. This is similar to the natural drying process, just that the added heat and the continuous blast of hot air will ensure the food is dehydrated in a matter of hours and not days.

The best setting will be to let the food dehydrate overnight in a 12-hour cycle so that it’s not too fast and not too slow. The machine will run its cycle and shut off. The dehydrator has screen layers on which you can place the onions. Layer them evenly and take care not to stack them. A layer or two would be fine as the drying process is faster. 

Drying using the oven:

This is the quickest, easiest, and most recommended method of dehydrating them. Although the onion powder will lose some of its taste, the time and effort saved more than makes up for it. Involves the use of an oven to use high heat as a method to dehydrate the onions. We will use this process in this article, and it has been detailed below. 

Nutrition details – Calories – 40kcal

Ingredients – Cleaned and finely sliced onions

Course – Seasoning Mix

  • Preparation time – 30 minutes (depending on the number of onions)
  • Cooking time – 1 hour 30 minutes
  • Cooling time – 30 minutes
  • Total time required – 2 hours 30 minutes

Materials needed 

  • 1 Nos. – Baking sheet for the oven
  • 1 Nos. – Parchment paper for the oven
  • A grinder like a food processor or blender to grind the dehydrated onions
  • Airtight storage container with lid, e.g., mason jar
  • Rice or Silica gel packet (optional, to prevent clumps due to moisture)


  • Use the parchment paper to line the baking pan.
  • Turn on the oven and set it to preheat at 140 degrees Fahrenheit. If the oven does not have such a low setting, use the lowest possible setting and let it preheat. 
  • Spread the sliced onions on the baking sheet in a fine layer. For even drying, ensure to spread it evenly so that there are no layers. 
  • Once the oven has reached the desired, preheat levels, place the baking sheet and pan inside the oven. Let the oven do its job. The high temperature inside the oven will slowly suck out all the onion slices’ moisture, thereby gradually drying out the slices. The temperature of the oven gets low enough not to burn the onion slices but still high enough to dehydrate them. 
  • As the onion slices dry, the upper surface exposed to the heat will start becoming crusty while the lower layer will stay soft. So ensure to shake the baking pan and stir or re-spread the contents to ensure the lower layers now face the heat. Do this every 10-15 minutes till the process is complete. Keep a watch on the onion slices and ensure they do not burn
  • Repeat this process until you can see that the slices are all dehydrated. You will know this as the dehydrated onion slices will appear dry and crumble between your fingers. This should take around 90 minutes at 140 degrees Fahrenheit but can be quicker too. So keep an eye and turn off the oven if you feel the onions have become completely crunchy and dry. If your oven’s minimum Temperature is higher than 140 degrees Fahrenheit, re-spread the contents every 10 minutes and checks the onion slices. At a higher temperature, the slices will dry out faster. Remember that the slices are fragile and can get burned in a few minutes, so be careful. 
  • The texture will tell you if the onions are done. Once done, remove the baking pan, transfer the dried onions to a plate or a flat container and let them cool down. 
  • Repeat the steps above for the next batch of onion slices, if any.
  • Once cooled, use a grinder, a coffee beans grinder, or a food processor, to grind them into fine powder. By now, the onion is already dry, crunchy, and fragile and so will quickly turn into powder. The onion powder is very fine. Therefore, wait for a few seconds after the grinding for the onion powder to settle down. 
  • In an airtight, you should store the powder in a container or jar. Mason jars are the best. You can also re-purpose old spice containers as they are also airtight. Keep it in a dry and cool place in your kitchen. This homemade onion powder can easily last up to a year, or two if stored correctly. 
  • Keep a tiny bag of rice or Silica gel packet in the jar. They will absorb all the residual moisture and prevent onion powder from spoiling. 

Nutrition Details: Serving: 1batch 

Protein: 1.1g | Carbohydrates: 9.34g | Fat: 0.1g | Saturated Fat: 1g | Fiber: 1.7g |Potassium: 146mg | Magnesium: 10mg | Zinc: 0.17mg | Manganese: 0.129mg | Phosphorous: 29mg | Sugar: 4.24g | Calcium: 23mg | Iron: 21mg | Calories: 40kcal |


Onion powder has numerous benefits from the seasoning of foods on the dining table. Using it as a condiment, flavoring any ground meat, or just using it in the recipe directly without waiting to chop all the onions, which can be time-consuming every time. We have shared an effective and healthy way to make onion powder and store it for all your needs. Happy Cooking!

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