Yellow onions, also called brown onions, are high in sulfur and have a very strong, almost spicy flavor profile. Generally considered more of a cooking onion than one to be eaten, raw, yellow onions are a culinary staple and an excellent way to add nutrition to various dishes. Our question is, do yellow onions have quercetin?
Quick Answer: Yes – Yellow onions do contain quercetin. Compared to other similar foods, their quercetin content is high.
Quercetin Content of Yellow Onions
Yellow onions contain 15mg/100g of quercetin and are rich in 13 vitamins and minerals.
Are Yellow Onions High in Quercetin?
Compared to other foods, yellow onions are very high in quercetin.
Let’s take a look at how they compare to 5 similar foods.
- Red onions outstrip yellow onions offering more than double the quercetin content with 31mg/100g.
- Sweet onions contain no quercetin at all.
- Garlic only provides 1.74mg/100g of quercetin, giving yellow onions a seven-fold advantage.
- Fennel bulbs are no competition for yellow onions containing only 0.23mg/100g of quercetin.
- Horseradish root provides 0.28mg/100g of quercetin, 14.72mg/100g less than yellow onions.
National Library of Medicine “Waste streams in onion production: Bioactive compounds, quercetin and use of antimicrobial and antioxidative properties”: https://pubmed.ncbi.nlm.nih.gov/33838387/#:~:text=Furthermore%2C%20the%20dried%20skin%20ethanol%20extract%20of%20yellow,25%20mg%20Trolox%20equivalents%20g-1and%20high%20antimicrobial%20activity.
USDA Database for the Flavonoid Content of Selected Foods: https://www.ars.usda.gov/arsuserfiles/80400525/data/flav/flav_r03.pdf