Citrus fruits, including grapefruit, oranges, tangerines, lemons, and kumquats, share distinct characteristics: a tough rind and white pith encasing juicy segments. These fruits thrive in tropical and subtropical climates and are available year-round.

According to the U.S.-based health website Healthline, citrus fruits are an "excellent source of vitamin C (ascorbic acid)". This micronutrient boosts the immune system and maintains smooth, elastic skin. Additionally, citric acid aids skin care, cell regeneration, acts as an antioxidant, reduces inflammation, and enhances mineral absorption in the body, as reported by Nguyen Tri Phuong Hospital's information portal in Ho Chi Minh City. Vitamin C and citric acid are the key components responsible for the sour taste of citrus fruits.

On hot days, many people crave a cold drink with a sweet and sour taste. Experts explain that the sourness stimulates saliva production, moistening the mouth and thereby reducing thirst. Dehydration in hot weather often leads to dry mouth and a desire to drink. Japanese research shows sour tastes stimulate more saliva than other flavors, moistening the mouth and creating a hydrated feeling even after drinking.

The U.S. food website Tastingtable states that the hydrating effects of citrus fruits operate on multiple levels. Crucially, they encourage people to drink more water on hot days while supporting better bodily functions. Proper hydration regulates body temperature, lubricates joints, and transports nutrients where needed. These fruits also contain electrolytes, which replenish those lost through sweating during outdoor exercise.

Sour drinks stimulate saliva production, moistening the mouth and reducing thirst. *Photo: Manh Hung*

Given their juiciness, beneficial components, and palate-stimulating sourness, nearly one-third of all citrus fruits are used for juice production, according to Healthline. In traditional Vietnamese cuisine, many oranges, lemons, and kumquats are often prepared with honey and green tea to create refreshing and healthy beverages, such as lemon tea, kumquat tea, and honey-soaked lime water.

As global integration increases, Japanese yuzu has also become a favored citrus fruit among many Vietnamese. Yuzu boasts a distinct aroma and a delicate sour taste, utilized in numerous drink recipes for effective thirst-quenching. A splash of yuzu juice or a few finely shredded zest strips imparts a unique, refined fragrance that no other citrus fruit can replicate, enhancing both food and beverages.

Many beverage brands have incorporated citrus fruit ingredients into their products to boost their refreshing qualities and provide a sense of invigoration for consumers. An example is the Boncha brand with its Boncha Citron Honey Tea Collection, featuring three flavors: Bon-Citron kumquat, lemon, and yuzu (Japanese lemon).

Boncha honey tea products are a popular choice among young people for summer refreshment. *Photo: Manh Hung*

The combination of citrus fruit ingredients with pure honey and green tea in the product line creates a widely favored refreshing drink. "The beverage offers the cool, tart taste of citrus fruit—whether lemon, kumquat, or Japanese yuzu, depending on the version—the subtle sweetness of honey, and a mild astringency from the tea, making it ideal for quenching thirst", described Thanh Hang, a student at Ho Chi Minh City University of Economics and Law, about Bon-citron.

Hoang Phuc, a student at Hanoi University of Science and Technology, shared his refreshing experience drinking cold citrus-infused honey tea on hot days: "When my throat is dry and parched after being out in the sun, a cold sip of Boncha, with its complete blend of sour, sweet, and astringent flavors, helps dispel fatigue and re-energizes me to continue my tasks."

Diep Chi