Springtime for Hualien’s Outsize Pomelos:

We arrive at the agricultural products processing lab of the Ministry of Agriculture’s Hualien District Agricultural Research and Extension Station (HDARES). A number of Wendan-flavored products are on display, including dipping sauce, jam, soy sauce, and beer. There are also cleaning and washing products developed with Wendan essential oil and pomelo floral scent, while pomelo mosquito-repellent incense is available on the market. On opening a bottle of Wendan essential oil, the fragrance that emerges is different from that of other citrus oils, inspiring astonished exclamations at the gentle, refreshing aroma.

The pain points of Wendan farming

Lab director Chen Bo-han states frankly that fruit farmers newly engaging in Wendan pomelo cultivation must wait five years for their first harvest, and young trees mostly produce large pomelos above 600 grams in weight, the maximum size for top-grade fruit used in gift packs for Mid-Autumn Festival. In major Wendan growing areas such as Hualien and Tainan, on trees up to ten years old these oversized fruits constitute 30–40% of the total harvest, severely impacting farmers’ incomes and becoming a source of regret for all the hard work put into growing them.

When economist Chen Chi-chung was minister of the former Council of Agriculture (now the Ministry of Agriculture), he instructed HDARES to study the feasibility of making full use of outsize Wendan pomelos, to improve farmers’ incomes. This has been part of a wider effort to develop products that make citizens aware of Wendan year-round, not only at Mid-Autumn Festival.

Setting to work on developing such products, HDARES researcher Chiou Shu-yuan discovered that hand-peeling of pomelos was too slow to produce adequate raw material. At a rate of ten kilograms of Wendan per person per hour, with flesh content of only 30–40%, each individual could produce only three to four kilos of pulp per hour.

Pomelo trees up to ten years old produce a significant proportion of oversized fruits exceeding 600 grams.

HDARES has developed earlier ripening pomelo varieties, enabling farmers to stagger production to avoid harvesting gluts that depress prices.

Automated processing

To accelerate the production of raw materials, the HDARES agricultural machinery lab spent five years developing a complete automated processing line for Wendan fruits. This system went into use at the Ruisui Farmers’ Association in Hualien in 2025.

The most challenging step in the processing chain was segmenting the fruit—removing the peel, pith, membranes and seeds to leave only the flesh. Li Yi-hua, head of the HDARES machinery lab, points out that there were no Wendan peeling devices on the market, and the difficulties of segmenting were exacerbated by the teardrop shape of the fruit, and the bitter white pith and segmental membranes inside it. Overcoming these difficulties one by one, the R&D team was able to produce a system that can handle up to 1,000 kg of fruit per hour, processing as much as three to four metric tons of pomelos per day.

 

1.Cleaning and drying: Freshly harvested Wendan pomelos are washed and air dried.

2.Weight grading: Pomelos are weighed and graded by machine. Oversized fruit (above 600 grams) are sent for processing, while smaller fruit are sold fresh.

3.Essential oil extraction: Rollers with small steel needles rupture the oil sacs in the peel to release the essential oil, which is washed into a collection channel with water.

4.Automatic peeling: First the tops and bottoms of the fruit are cut away, after which a cutting machine separates the peel and white pith from the pulp segments.

5.Pulp separation: A pulp separating machine uses a screw and extrusion mechanism to separate the pulp from the pith and segment membranes. The pulp falls into a collector while the pith and membranes are carried away by the rotating screw.

Processing equals empowerment

Chen Bo-han notes that the essential oil extracted from Wendan peels has a unique, refreshing fragrance that can be used in scent diffusers, aromatic products, and cleaning products. Meanwhile, the sweet–sour flesh can be made into Wendan dipping sauces and jams, while bakeries have developed pomelo brownies and Danish pastries as well as European-style breads made with honey, pomelo, and nuts. The distinctive aroma also appears in craft beers.

Thus far HDARES has developed over 20 processed Wendan products, and successfully transferred relevant technology to farmers’ associations. In addition, the Ruisui Farmers’ Association holds a seasonally appropriate “pomelo fragrance chase” road running race that spotlights unique local characteristics.

This revolution in utilizing oversized Wendan not only bolsters farmers’ incomes, it spreads this uniquely Taiwanese pomelo fragrance to dining tables and daily life in multifaceted ways. It’s just the beginning of springtime for large Wendan pomelos.

The technology for making Wendan pomelo dipping sauce and jam, with pomelo pulp as the main ingredient, has been transferred to the Ruisui and Fuli farmers’ associations.

Essential oil, craft beer, and pomelo jam were all developed utilizing Wendan peel.

Multiple products have been developed with pomelo fragrance, including handmade soap, beer, and hand washing lotion.

Refreshingly fragrant white pomelo flowers bloom from February to April each year. (courtesy of HDARES)