Suāngān chá

Suan Gan Cha (Suāngān chá, 酸柑茶) — “sour citrus tea,” a traditional beverage of Taiwan’s Hakka (客家, Kèjiā) people. It is made from the citrus 虎頭柑 (hǔtóu gān; in academic papers — Citrus aurantium L. cv. Hutou Gan), which, due to its very sour pulp, is also called 酸柑 — “sour citrus.” According to academic descriptions, the fruit is hollowed out, stuffed with tea leaves — some add a small amount of medicinal herbs — and repeatedly steamed and dried. This technique is called 九蒸九曬 (jiǔ zhēng jiǔ shài), “nine steamings, nine sun-dryings.” The result is a flat, round, dark fruit bound with string, stored and aged for years. Sources do not agree on which tea class it belongs to: Taiwanese teaching materials present it as an example of secondary processing, while no source specifies which leaf should be placed inside.

1. Classification and Origin

• Type: Sources assign 酸柑茶 to different categories, and none of them matches the six basic tea classes.
  • Teaching slides about tea, captioned as provided by the Tea Research and Extension Station (茶業改良場, Cháyè gǎiliángchǎng), place 酸柑茶 under the category of secondary processing (再加工, zài jiāgōng) — alongside scented tea (薰香茶, xūnxiāngchá), tea powder, and tea bags. The slides are attached to a teaching plan from a tea farm in Miaoli County on the food and agricultural education portal of Taiwan’s Ministry of Agriculture; this is teaching material, not a standard.
  • An article in the journal Foods (2026) defines 酸柑茶 as a solid-state aged mixture of citrus and tea leaves.
  • A research project application from the National Taiwan Ocean University (2019) calls it “fermented and aged tea” (發酵茶和老化茶, fājiàochá hé lǎohuàchá), without explaining what “fermented” means here.
  • An author of a 2010 essay on Hakka cuisine writes that 酸柑茶 “can be called a pressed tea” (堪稱緊壓茶, kānchēng jǐnyāchá); this is a comparison, not a classification.
  • Sources name different leaves inside the fruit (see Section 3), so the base tea does not determine the class either. Therefore, this encyclopedia does not assign 酸柑茶 to any of the six classes and describes it as a form — tea in citrus — and a processing method.
• Category: Hakka tea in citrus; an artisan product, not a plant cultivar or a trademark.
• Origin: Taiwan (臺灣, Táiwān), Hakka communities. Primary sources do not state directly where it is currently made. According to a 2010 essay, at that time it was mainly in the Taoyuan–Hsinchu–Miaoli area (桃竹苗, Táo-Zhú-Miáo), while in southern Taiwan it was rare. Samples for academic work were purchased from a private tea factory in Taoyuan (桃園, Táoyuán) and in Toufen (頭份, Tóufèn), Miaoli County (苗栗, Miáolì); according to a 2017 report, a demonstration of traditional production took place in Shigang (石岡, Shígāng) Township, Taichung. Verified sources do not establish where the practice itself came from.
• Citrus: 虎頭柑 grows mainly in Fujian (福建, Fújiàn) and Guangdong (廣東, Guǎngdōng); in Taiwan it is planted scattered, mostly in Taichung (台中, Táizhōng), Hsinchu (新竹, Xīnzhú), Miaoli, and Taoyuan.
• Standard and marks: A search of the local standards registry of mainland China in October 2026 (queries 酸柑, 酸柑茶, and 柑茶) yielded no records. Taiwanese registries of standards, marks, and heritage were not checked, so no claim is made here about the absence of a Taiwanese standard or mark for 酸柑茶.
• Geographic coordinates: The product has no single point of origin; coordinates are not provided.

2. History and Cultural Significance

• History:
  • Age. There are no dated historical records in verified sources. A 2017 Taiwanese report writes that Hakka people have passed down the craft “for over a hundred years”; this is an estimate without dates or references.
  • Tea from festival citrus. According to Taiwanese press and Chinese Wikipedia, 虎頭柑 fruits are bought for Lunar New Year and placed as offerings on home altars. They are almost inedible: the pulp is unbearably sour. A 2011 television feature explains that after Spring Festival, unsold fruits lose value and would otherwise be discarded: the only use left is for tea. According to a 2017 report, after Lantern Festival the dehydrated, shriveled fruits were usually thrown away, but thrifty Hakka put them to use; a 2010 essay writes the same about fruits dried out after Spring Festival. According to Chinese Wikipedia, 酸柑茶 is made from fruits that are abundant or left over from offerings, most often after Spring Festival.
  • Tea and medicine. A 2020 academic article writes that in the past, Hakka people in mountainous areas drank 酸柑茶 for colds, and elders in farming families kept it at home “just in case.” According to Chinese Wikipedia, for Hakka it is “both tea and medicine,” usually boiled only when someone was ill. More on this aspect in Section 8.
  • 2017. According to a report, in Shigang a local association held a demonstration of traditional 酸柑茶 production: a representative feared the craft might disappear.
  • 2018–2020. The Hakka Affairs Council (客家委員會, Kèjiā Wěiyuánhuì) funded two projects at the National Taiwan Ocean University: on the cultural history of 酸柑茶 (2018) and on its active compounds and their connection to aging year (2019–2020). The authors of the first application wrote that Hakka studies contain no records of 酸柑茶.
  • 2020. An article in the Taiwanese journal Journal of Agriculture and Forestry appeared on two major flavonoid glycosides of 虎頭柑 peel in 酸柑茶 (see Section 7).
  • 2024. According to the Central News Agency, the Miaoli County government promoted 酸柑茶 at the Tokyo International Food Exhibition among notable local products — together with “Eastern Beauty” (東方美人茶, Dōngfāng měirén chá).
  • 2026. The authors of the Foods article write about the gradual decline of the craft: fruits are scarce, seasonal, and traditional production relies heavily on manual labor and does not fit well with industrial production.
• Name:
  • 酸柑茶 (suāngān chá) — the Chinese product name in academic articles, university project cards, and Taiwanese press. 酸 (suān) — “sour,” 柑 (gān) — “mandarin, citrus,” 茶 (chá) — “tea.”
  • 酸柑 (suāngān) — the second name for the 虎頭柑 fruit. A 2020 academic article explains it by the very sour pulp; a 2017 report calls this a folk name.
  • 虎頭柑 (hǔtóu gān) — literally “tiger-head citrus”; sources do not explain the origin of this name.
  • Latin script. In academic publications, “Tsuan-Kan tea” (Foods, 2026), “Hakka sour citrus tea” (2020), and “bitter orange tea” (2019 project application) appear. “Tsuan-Kan” is not pinyin.
  • Pinyin. Suāngān chá in the heading is the standard dictionary reading of the characters: 酸 reads suān, 柑 reads gān, 茶 reads chá; there are no ambiguous characters in the name.
  • Suan Gan Cha is the English rendering used in this encyclopedia. In English-language descriptions, the name is sometimes translated as “tea in a sour orange.” One 2005 English-language description, judging by the matching key features, calls the same product “Suan-Gan” (“sour orange”); this is a nonstandard rendering, and there is no direct source where both names appear together. “Orange” here is a colloquial word: academic articles classify 虎頭柑 as Citrus aurantium, that is, bitter orange.
• Cultural significance:
  • Thrift. A 2011 Taiwanese television feature and a 2017 report describe 酸柑茶 as an example of Hakka thrift: fruits that would otherwise be thrown away went into tea. The 2011 feature’s title speaks of a “cup of diligence and thrift.”
  • Family of fruit teas. According to a 2010 essay (quoting a tea garden owner), the Hakka have two “fruit teas” — 酸柑茶 and pomelo tea (柚子茶, yòuzi chá); they are made by the same method, and 酸柑茶 is the main one. According to Chinese Wikipedia, 柚子茶 is prepared after Mid-Autumn Festival, while 酸柑茶 — after Spring Festival.

3. Botanical Description and Raw Materials

• Tea cultivar: Not named by any verified source. Sources describe the leaf placed inside differently: a 2010 essay — leftovers from tea production (茶角, chájiǎo), “not good tea at all”; a 2005 English-language description — cut oolong. In the laboratory model of the 2026 article, oolong was used, but this was the researchers’ choice, not a traditional norm. A 2017 Taiwanese report writes that the hollowed fruit is filled with “tea or herbs,” while academic articles describe the product only with tea leaves; whether a filling can be entirely without tea is not directly established by sources (see Section 5, “Where descriptions diverge”).
• Citrus 虎頭柑:
  • Botanical name. In the 2020 and 2026 academic articles — Citrus aurantium L. cv. Hutou Gan; Citrus aurantium is bitter orange in English. The 2019 project application writes Citrus × aurantium.
  • Origin of the fruit. According to a tradition cited by the 2020 article, 虎頭柑 is a hybrid of pomelo (柚子, yòuzi) and bitter orange (酸橙, suānchéng); according to another version, the citrus is grafted onto pomelo as rootstock. The authors consider that the simultaneous presence of naringin and hesperidin in the peel supports this tradition. The article offers no genetic proof, and the botanical status of 虎頭柑 is not established here.
  • Pulp. Very sour — hence the name 酸柑. According to a 2017 report, the fruit looks good but is not fit to eat.
  • Size. According to a 2017 report — twice as large as a regular ponkan mandarin (椪柑, pènggān).
  • Fruit season. From October through February of the following year.
  • Where it grows. Main production — Fujian and Guangdong; in Taiwan — scattered plantings, mainly in Taichung, Hsinchu, Miaoli, and Taoyuan.
• Herbs and additives: Optional. A 2020 academic article writes that some add a small amount of medicinal herbs for flavor. A 2010 essay calls “standard” (標準工序, biāozhǔn gōngxù) a sequence in which the ground pulp is mixed with salt, licorice (甘草, gāncǎo), mint (薄荷, bòhe), perilla (紫蘇, zǐsū), and tea, but notes there that herbs differ from household to household: chrysanthemum (菊花, júhuā), goji berries (枸杞, gǒuqǐ), and other plants are also used. One factory in Longtan (龍潭, Lóngtán), according to the same essay, puts only tea into the fruit, without herbs.
• Pulp in the filling: According to a 2017 report and a 2010 essay, the pulp is not thrown away: it is removed, seeds are taken out, and the pulp is mixed with tea and returned to the fruit. Academic articles write more briefly — the fruit is hollowed out and stuffed with tea — and neither confirm nor refute this detail.
• Harvest: Sources do not name the time of tea leaf harvest for 酸柑茶. The product itself, according to Chinese Wikipedia, is most often made after Spring Festival, when fruits remain from New Year offerings.
• Harvest standard: No data: what shoot and how many leaves are used for the filling is not described.
• Raw material requirements: No norms. According to a 2017 report and a 2010 essay, fruits left after festivals and already dehydrated are used.

4. Terroir and Growing Characteristics

Terroir for 酸柑茶 in the usual sense cannot be described: the base tea is not tied to a single garden, and the citrus in verified sources is described only by cultivation areas.

• Region: Hakka areas of Taiwan. According to a 2010 essay, at that time mainly Taoyuan, Hsinchu, and Miaoli. Verified sources contain no descriptions of relief or climate specifically for 酸柑茶.
• Citrus: 虎頭柑 in Taiwan is grown scattered — in Taichung, Hsinchu, Miaoli, and Taoyuan; the main areas for this citrus are Fujian and Guangdong. Fruit season — from October through February.
• Growing altitude: No data.
• Soils: No data.
• Sun as part of the technology: For 酸柑茶, weather matters less in the garden than during production. According to masters’ descriptions, fruits are repeatedly dried in the sun; according to the master who demonstrated the process in 2017, in good weather they must be taken outside.

5. Production Technology

Academic articles describe the technology of 酸柑茶 in one sentence: the fruit is hollowed out, stuffed with tea leaves, and processed by repeated steaming and drying — the 九蒸九曬 technique. A 2026 article adds that this yields a tea of distinctive flavor and dark-brown color. A detailed sequence is known only from descriptions by individual masters — in a 2017 Taiwanese report and a 2010 essay — and it is presented below with that caveat. Temperatures, steaming durations, and pressing force for the traditional product are absent from verified sources.

1. Preparing the fruit: According to a 2010 essay, the top of the fruit is cut out with a special metal cylinder, and the cut peel is kept as a lid; the pulp is removed, seeds are taken out, and the pulp is ground into a puree.
2. Filling: The pulp is mixed with tea leaves — according to various descriptions, also with herbs and salt — and firmly packed back into the fruit.
3. Closing and binding (綑綁, kǔnbǎng): The fruit is closed with the cut lid and tied. A 2018 university project card writes that during production the fruits are tied with string; a 2017 report names cotton thread; a 2010 essay — wire or rubber band.
4. The 九蒸九曬 cycle: The tied fruits are steamed (蒸, zhēng) in a steamer (蒸籠, zhēnglóng), dried in the sun (曬, shài), heated (烘, hōng), and pressed (壓, yā) — and the cycle is repeated. According to a 2017 report and a 2010 essay, there are nine repetitions, until the fruit is dried through. According to the master who demonstrated the production in 2017, the fruits are steamed, pressed, and heated every day, and taken out into the sun in good weather.
5. Pressing and shape: The finished product is flat, round, and dark — so describes a 2018 project card. How exactly it is pressed differs among masters: one factory, according to a 2010 essay, squeezes fruits arranged in rows between two boards; a 2005 English-language description mentions a press under a special wooden bench for several days.
6. Aging: Dried fruits are stored and aged for years (see Section 10).

Duration: About two to three months according to a 2017 report and three months according to a 2010 essay. There are no other data on duration in verified sources.

Where descriptions diverge:

• Tea or herbs. Academic articles describe the product with tea leaves; a 2017 report writes “tea or herbs.”
• Binding. In most descriptions, the fruit is tied. The factory from the 2010 essay proceeds differently: it does not use the cut peel, but takes a lid from another, larger peel so it fits more tightly and does not fall off as the fruit shrinks during steaming and drying — therefore it does not tie the fruits.
• Steaming. A 2005 English-language description does not mention steaming and writes that the fruit is wrapped in cloth and pressed; Taiwanese sources where the process is described name the 九蒸九曬 technique.
• Laboratory model. The 2026 article made an experimental 酸柑茶 from orange (Citrus sinensis) and oolong and studied how aging conditions affect it. This is a model, not a description of the tradition, and its regimes do not apply to the traditional product.

6. Organoleptic Characteristics

There is no standard description of 酸柑茶 taste and aroma; below are impressions of individual authors, with indication of who expressed them. They are difficult to compare: herbs, tea, and aging period differ for each sample.

• Dry leaf appearance: What is stored is not leaves but a whole fruit: flat, round, dark to black, tied (2018 project card); the 2026 article calls the color dark brown. According to a 2010 essay, the finished fruit is hard as stone; a 2017 report compares its appearance to pu-erh. Sources do not describe how the leaf looks inside the fruit.
• Dry leaf aroma: No descriptions in verified sources.
• Infusion aroma: According to a 2017 report, the infusion combines the aroma of tea and the aroma of citrus. A 2005 English-language description notes notes of medicinal herbs.
• Taste: A 2017 report describes the infusion as mellow and refreshing, with a slight sourness; a 2005 English-language description — also as slightly sour. The author of the 2010 essay writes that the herbal taste in 酸柑茶 is much stronger than the tea taste. According to the 2020 article, after years of aging the taste becomes softer.
• Infusion color: The only description is the 2005 English-language one: in color like red (in English terminology — black) tea. This refers to the color of the infusion, not the class.
• Wet leaf (brewed leaf): No descriptions. According to a 2010 essay, the broken fruit is brewed together with the peel, so the vessel contains leaves, peel, and herbs, if any were added.

7. Chemical Composition

There is no complete analysis of 酸柑茶 in verified sources; research concerns mainly the citrus part.

• Peel flavonoids: According to the 2020 article, the main flavonoid glycosides of 虎頭柑 peel are naringin and hesperidin. In a purchased 酸柑茶 sample, both substances were detected, but notably less — about 10–30 % of the content in 虎頭柑 peel. This is a rough estimate based on peak areas, with variation between batches.
• Why less: In the abstract, the authors link the reduction to years of aging; in the results section — probably to heating during production. To test this, they heated 虎頭柑 peel weekly for four weeks, imitating 九蒸九曬, and the content of both substances gradually declined. According to their data, in 酸柑茶 and in aged tangerine peel (陳皮, chénpí) both substances decrease to 10–30 % of the original peel, and the taste becomes mellow.
• Active compounds and aging year: The 2019–2020 project studied the active compounds of 酸柑茶 and their connection to aging year; the results of the project are not presented in verified sources.
• 2026 laboratory model: The Foods article studied antioxidant activity and inhibition of the enzyme α-glucosidase in a model made from orange and oolong, comparing it with a purchased sample. The authors themselves call their data preliminary, obtained in vitro; this encyclopedia does not transfer them to the traditional product made from 虎頭柑.
• Tea part: A general principle, not data about this product: tea leaves contain caffeine, polyphenols, and amino acids. How much of them is in 酸柑茶 and how steaming, drying, and aging affect them is not reported in verified sources; moreover, the base leaf differs among masters.

8. Health Properties

There are no verified data on the effect of 酸柑茶 on humans: no trials of the beverage were found in verified sources.

• Folk use. According to the 2020 academic article, in the past Hakka people in mountainous areas drank 酸柑茶 for colds. The 2020 article and the 2017 report also mention phlegm and fever; the report and Chinese Wikipedia mention cough; the article and report relay this with the word 據說 (jùshuō) — “it is said.” This is a description of tradition, not an established effect.
• Explanation by the 2020 authors. The authors link traditional use to literature data on naringin and hesperidin. This is their interpretation, not a trial of the beverage.
• Laboratory data. The 2026 model results were obtained in vitro on orange and oolong and do not prove benefits of the beverage.
• Herbs in the composition. The set of herbs differs from household to household, so their effect cannot be attributed to 酸柑茶 in general. If the composition matters, it is worth asking the person who made the fruit.

9. Brewing

Sources describe only how to prepare the fruit: according to a 2010 essay, the rock-hard fruit is cracked with a hammer and brewed together with the peel; a 2017 report also writes that it is brewed after being broken into pieces. According to Chinese Wikipedia, in Hakka daily life 酸柑茶 was boiled (煮, zhǔ). Verified sources give no proportions, temperature, or steeping time. Below is general practice for aged pressed teas, not a recipe for this product.

• Water temperature: As for most aged pressed teas — boiling water or water near boiling; or boiling, as in Hakka daily life.
• Amount of tea: As for most aged pressed teas — about 5–7 g per 100–150 ml for gongfu brewing. For 酸柑茶 no norm is established: a piece contains peel and herbs, and strength should be adjusted to taste.
• Teaware: For cracking — a hammer, as in the descriptions. For brewing — as for most aged teas: a clay teapot or a gaiwan (盖碗, gàiwǎn); for boiling — a kettle on fire.
• Process:
  1. Crack the fruit with a hammer and select a piece together with peel.
  2. Warm the teaware with boiling water.
  3. Place the piece into the teaware.
  4. As for most aged pressed teas, the first short rinse can be discarded: it warms and softens the piece.
  5. Pour boiling water and steep, or boil on low heat; adjust time to taste — there are no data for 酸柑茶.
  6. Pour the infusion. Sources do not say how many times one piece is brewed; dense aged material usually withstands several infusions — this is general practice, not data about 酸柑茶.

10. Storage

• Stored for years. According to the 2020 academic article, in old farming households elders kept 酸柑茶 at home “just in case”; the 2026 article calls it an aged mixture of citrus and tea leaves.
• What happens during aging. According to a 2010 essay, the fruit shrinks and decreases over time, so it has to be re-tied, and the color darkens — from earthy yellow through dark brown to black. The 2020 article writes that the taste of the aged product is softer, and its peel flavonoids are less (see Section 7).
• Duration. There are no norms for aging duration. The connection of active compounds to aging year was studied by the 2019–2020 project; its results are not presented in verified sources.
• Conditions. Sources do not describe storage conditions. General practice for aged teas, not data about this product: a dry, clean place without direct light, foreign odors, and humidity fluctuations. For a fruit with peel and herbs, dampness is especially undesirable.

11. Price and Counterfeits

There are no price benchmarks suitable for an encyclopedia in verified sources.

• What affects value. The authors of the 2018 application write that the market value of 酸柑茶 grows with time, and compare this to pu-erh. The comparison is theirs, not a classification.
• How to avoid confusion:
  • Composition. The filling is not standardized: the base tea differs among masters, herbs differ from household to household, and according to a 2017 report the fruit is filled with “tea or herbs.” If it matters whether there are tea leaves inside and which herbs, this should be checked with the producer.
  • Resemblance to pu-erh. A 2017 report compares the appearance of 酸柑茶 to pu-erh; a 2018 application compares its value during aging; this does not make it pu-erh.
  • Xinhui citrus teas. Mainland teas in peel from Xinhui (Guangdong) are a different product: the pulp is removed, the vessel is the peel of the mandarin 茶枝柑 (cházhīgān) with pu-erh or another tea inside. 酸柑茶 is made from 虎頭柑 and repeatedly steamed and dried.
  • Marks. No standard or mark by which the authenticity of 酸柑茶 can be verified has been found; Taiwanese registries were not checked.

12. Interesting Facts

• The raw material is often fruits left after New Year offerings: unbearably sour and shriveled, they would have been thrown away, but thrifty Hakka, according to Taiwanese press accounts, turned them into tea.
• In Taiwanese teaching slides about tea, 酸柑茶 stands alongside scented tea, tea powder, and tea bags — as an example of secondary processing.
• The 九蒸九曬 formula does not belong to one product: the same repeated processing appears, for example, in the non-tea Guanshan Lianqiao Cha (冠山连翘茶, Guānshān liánqiào chá) from the mainland, in the mainland record 九蒸九晒.
• In the 2020 article, chemical analysis of the peel is used to test a Hakka tradition about the hybrid origin of 虎頭柑: the joint presence of naringin and hesperidin, according to the authors, supports the tradition.
• The author of the 2010 essay called 酸柑茶 “one might say, a pressed tea” and writes that the finished fruit is hard as stone and is cracked whole with a hammer.
• The authors of the 2018 application noted that Hakka studies contain no records of 酸柑茶, although the product is distinctive.

13. Comparison with Similar Teas

• Gan Jie Cha (柑桔茶): A general overview of citrus teas in the encyclopedia. In the scheme described there, the pulp is removed; Hakka, Taiwan, and 虎頭柑 are not mentioned in the overview.
• Da Hong Gan (大红柑, dà hóng gān) and Ju Pu (橘普, jú pǔ): Xinhui citrus teas from Guangdong: the vessel is mandarin peel, inside is pu-erh or another tea, with no pulp or herbs. 酸柑茶 has a different fruit, repeated steaming and drying, and, according to masters’ descriptions, pressing and pulp returned to the fruit together with tea.
• Xinhui aged tangerine peel (新会陈皮, Xīnhuì chénpí): Not a tea but a peel. The 2020 article compares 酸柑茶 with it: in both, during aging the content of the two main peel flavonoids decreases, and the taste mellows.
• Hakka pomelo tea (柚子茶, yòuzi chá): According to a 2010 essay, made by the same method but in pomelo; according to Chinese Wikipedia — after Mid-Autumn Festival.
• Pukeng Cha (蒲坑茶, Púkēng chá): A Guangdong dark tea. According to a 2022 press report, one enterprise places it in pomelo, but this is a different tea and a different tradition.
• Dongfang Meiren (東方美人, Dōngfāng měirén): An oolong from the same area — Hsinchu and Miaoli counties; in 2024 Miaoli County promoted both products at one exhibition.
• Taiwan Cheng Cha (臺灣橙茶, Táiwān chéngchá): Despite the “orange” name, this is not tea in citrus: according to a 2026 English-language description, it is a leaf processing technology presented in Taiwan in 2024.
• Kejia Chao Lü (客家炒绿, Kèjiā chǎolǜ): What it shares with 酸柑茶 is only the people: it is a mainland Hakka roasted green tea.

In conclusion:

Suan Gan Cha is a Hakka way of not letting either festive citrus or tea leaves go to waste. The 虎頭柑 fruit, too sour to eat, is stuffed with tea, and sometimes with herbs, steamed and sun-dried again and again — yielding a hard, dark fruit that is stored for years. In it, tea, citrus, and household life come together: family elders kept it in reserve, and brewed it by cracking the fruit with a hammer.

Much in 酸柑茶 is not standardized: which leaf to use, whether to add herbs, how long processing and aging last. The craft, according to researchers, is thinning out: fruits are scarce, and the work is largely manual. For those interested in tea as part of local life rather than as a cultivar with an exact brewing recipe, it shows how Taiwan’s Hakka made do with what was at hand.

Sources

Documents and publications

1. α-Glucosidase Inhibitory Activity of Tsuan-Kan Tea in Different Solid-State Aging Models: Phytochemical Biotransformation, Volatile Profile, and Molecular Docking — Foods (MDPI), vol. 15, iss. 14 (2026), art. 2535; DOI 10.3390/foods15142535; PMID 42511281; Yang Y.-C., Chiang Y.-C., Chiang P.-Y. (Department of Food Science and Biotechnology, National Chung Hsing University, Taichung)
2. 土地與生活的美學--客家酸柑茶的文化敘事 — National Taiwan Ocean University Research Hub; Funding Organization: Hakka Affairs Council; 2018-01-01 — 2018-11-30; 250千元; GRB id 12469952
3. 客家酸柑茶之活性成分鑑定分析與年份之相關性探討 — National Taiwan Ocean University Research Hub; Funding Organization: Hakka Affairs Council; Department of Food Science; 2019-08-01 — 2020-07-31; 240千元; GRB id 13249123
4. 偵測客家酸柑茶中虎頭柑皮的兩個主要黃酮配醣體 / Detection of Two Major Flavonoid Glycosides of Hutou Gan Peel in Hakka Sour Citrus Tea — Journal of Agriculture and Forestry (National Chung Hsing University), 67(4): 261–272 (2020); 高俊陽、李悅群、王美琪、郭賓崇、曾志正 (Jun-Yang Kao, Yue-Chiun Li, Miki M.C. Wang, Ping-Chung Kuo, Jason T.C. Tzen); NCHU Graduate Institute of Biotechnology; NCKU School of Pharmacy
5. 111年度中苗地區農村食農教育與友善環境推廣計畫-食農教案創新 — 苗栗八甲茶園食農教案設計構想 — 食農教育資訊整合平臺 (fae.moa.gov.tw)
6. 全国标准信息公共服务平台 — 全国标准信息公共服务平台; 主管：国家标准化管理委员会; 主办：国家市场监督管理总局国家标准技术审评中心
7. 【一步一腳印】酸柑茶客家味　喝一杯勤儉精神 — TVBS新聞網; 記者 徐沛緹, 攝影 劉文彬; datePublished 2011-03-27
8. 九蒸九曬　石岡古農倉重現傳統酸柑茶製作 — 風傳媒 (storm.mg); datePublished 2017-02-23
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Full list — on the Sources page