Everything You Need To Know About Yuzu Fruit

You're probably familiar with fruits like strawberries, bananas, and apples. You may even be acquainted with some less well-known ones, like kiwi, papaya, and starfruit. But have you tried the yuzu or even heard of it?

If you have encountered yuzu, it was likely in teas or bath products. That's because the fruit can't be imported into the United States for fear of spreading agricultural diseases. Fortunately, it is grown domestically in citrus-friendly regions like California's San Joaquin Valley.

The yuzu fruit is small, typically the size of a golf ball, and rarely grows larger than a tennis ball. It has bumpy skin and large seeds and is believed to have developed as a hybrid of mandarin and another Southeast Asian citrus known as the Ichang papeda. Because of its somewhat bitter taste, the skin and juice are typically used in soups, dressings, and home and body goods. But what else is there to learn about this citrus fruit? Here's everything you need to know about yuzu.

Yuzu fruit originated in China but it's now grown in a variety of other nations, including Korea, Australia, the United States, and France. It also grows in Japan, where the fruit was initially consumed as medicine. Despite its holistic beginnings, yuzu is now a staple of Japanese cuisine. Japan produces 27,000 tons of yuzu each year and even held a tasting for the fruit in France in 2011. Thanks to that bit of marketing, buyers from 20 countries ordered yuzu. The following year, 30% of the yuzu fruit grown in Japan was exported to other countries.

Japan's Kochi Prefecture produces over 50% of the world's yuzu, despite being home to only 2,000 people. While other regions export hundreds of yuzu fruit that will be turned into ponzu (a citrus-flavored sauce) or juice, the ones grown in and shipped from the Japanese town of Monobe are blemish-free beauties that can be used intact. The juice is used to make vinegar, while the rind can be frozen for up to a year.

Your eyes aren't the only thing a daily dose of yuzu is good for. The fruit could also help boost your immunity. Besides the vitamin C and antioxidants that may make you more resistant to common diseases like the flu and colds, the fruit contains essential oils that could be invaluable. Soaking in a yuzu-infused bath is believed by some to help protect you against diseases, as per Everyday Health. Try placing two whole yuzu fruits in hot water to create a yuzu bath, cutting them to get more essential oils out of the experience.

When it comes to baths, many argue that the fragrance of this fruit is as important as its taste, if not more so. Of course, snacking on some in the bath isn't such a bad idea, as yuzu fruit contains antioxidants that can help fight free radicals that cause oxidative stress, as per Clinical Interventions in Aging.

Tests conducted using yuzu extract determined that ingesting this fruit may help prevent memory issues, as per a 2013 study published in the Journal of Nutrition. This was most significantly noted in testing conducted on rats that showed increased short-term memory in those exposed to yuzu.

A 2022 study showed significantly improved general and visual memory scores in participants under 74 who received citrus extracts (via Nutrients). Of note was the relationship between glycemic index, diabetes, and memory loss. This is where yuzu has its most significant impact in terms of memory. Studies showed that after eight weeks of introducing yuzu to a participant's routine, glucose levels decreased, leading to weight loss and improved cognitive function.

There is also evidence that citrus fruits reduce disruptions in the circadian cycle, which tend to occur more often in older individuals, and those most likely to be afflicted. Lack of sleep caused by these disruptions can contribute to cognitive decline. You should add yuzu to your routine if you haven't already by age 65.

A yuzu tree can take up to 15 to 20 years before it's ready to produce fruit. Of course, that plant must flower, grow fruit, and ripen before you can use it. But just how ripe it has to be is open to some debate.

When the yuzu fruit is fully ripe, it is yellow, but it can be used when the fruit is still green. Green yuzu will be much tarter than the fully mature, yellow fruit. Because yuzu is harvested in the fall, it stands to reason that the green variety would be available earlier in the year. This means you're best off looking for green yuzu in the summer. Green yuzu creates a kaffir lime sort of flavor, with peppery and piquant notes. Fully ripe yellow yuzu is challenging to locate in most western markets, however, while the green, not-quite-ripe variety can be almost impossible to find outside Japan. Try finding specialty markets or turning to yuzu juices if the fresh stuff is out of reach.

Unsurprisingly, yuzu fragrance is used in sprays, candles, and perfumes, as are many of its citrus brethren. But this one reportedly has stress-relieving benefits, too. It's often combined with grapefruit or bamboo. The fruit's scent is often described as a complex blend of sweet, bitter, and tart notes that make it popular for refined applications.

There are also notes of bergamot and lime in authentic and manufactured yuzu fragrances. Some recognizable perfumes that incorporate this unique scent include Versace Bright Crystal, Eau de Cartier, and Dali Wild.

The fruit is also powerful enough when it's refined that it can be used to perfume foods rather than flavor them. As chef Gregory Brainin told The New York Times, "It has an amazing floral citrus fragrance – you can smell it from across the room." He serves a scallop dish with yuzu juice misted onto it tableside with an atomizer.

Like other citrus fruits, yuzu has been shown to strengthen bones in animal studies. Researchers are hopeful yuzu fruit can be used to prevent age-related bone loss. According to Dr. Yoshifumi Kimifira, this is the result of collagen-derived peptides.

Though his studies are still in their infancy, Dr. Kimifira proposes that limonoids in the peel and seeds of the yuzu can benefit bone growth. The limonoid present in the fruit has already been shown to help bones. He also believes Nomalin may aid in the prevention of osteoporosis.

There has been some evidence in Dr. Kimifira's early animal studies that the fruit can help prevent bone loss over time. And because yuzu is traditionally used just for the juice, the seeds and skin typically go to waste. The researchers have created a way to turn these unused items into a paste, thus eliminating the waste and potentially helping keep bones strong, even in a person's later years.

Consuming citrus products can help prevent heart disease and strokes, as compounds found in citrus can keep blood platelets from clumping together and forming clots. According to Food and Chemical Toxicology, yuzu, in particular, contains naringin and hesperidin, two compounds known to have this anti-platelet effect, along with certain flavonoids in the peel.

Scientists were inspired to study the effects on humans after seeing positive anti-platelet results in rats (via Biomolecules & Therapeutics). Ethanolic yuzu extract was tested in humans, where researchers found that it could interrupt the processes responsible for clumping platelets and creating blood clots.

This effect is important for those who are at high risk for cardiovascular disease, including patients who have suffered strokes or may be at risk of one. It could be an excellent option for people who are sensitive to blood thinning pills and other treatments, like Tylenol.