Thai Coffee: Doi Chang Arabica and Oliang Explained

Thailand's coffee story is one of the sharpest contrasts in coffee geography: in the mountain villages of the north, Akha and Lisu hill tribe farmers grow arabica at altitude for the specialty market; in the street cafés and markets of Bangkok and the south, vendors serve oliang — a robusta-spice blend that owes more to Chinese immigrant culture than to any international coffee tradition. These two worlds share a country and a crop but almost nothing else.

The northern highlands: arabica and the Royal Project

Thailand's specialty coffee industry began as a government agricultural programme, not a market-driven initiative^[1].

In the 1960s and 1970s, the northern highland provinces of Thailand (Chiang Rai, Chiang Mai, Mae Hong Son) were centres of opium poppy cultivation. Hill tribe communities — Akha, Lisu, Karen, Hmong, and others — had grown poppies for generations as their primary cash crop.

King Bhumibol Adulyadej's Royal Project, launched formally in 1969, aimed to replace opium farming with alternative crops. Coffee was a key substitute: arabica thrives at the same altitude ranges as poppy, and the crop had market value. Royal Project stations in Doi Tung, Doi Inthanon, and other highland areas introduced arabica cultivation, technical training, and market access to communities transitioning away from opium.

Doi Tung: One of the flagship Royal Project sites, in the hills bordering Myanmar in Chiang Rai province. The Doi Tung Development Project was established in 1988 under the patronage of the late Princess Mother. Today, Doi Tung coffee is a well-established brand, produced by former hill tribe communities now employed in organised coffee cultivation and processing.

Doi Chang: A village in Chiang Rai province that became internationally prominent when Wicha Promyong, a Canadian businessman, partnered with the Akha community there in the mid-2000s to develop their arabica into an internationally marketed specialty brand. Doi Chang coffee attracted attention at specialty events and became a coffee tourism destination, drawing visitors to the village to taste coffee at the source.

Mae Salong: A former stronghold of the Kuomintang (Chinese Nationalist Army) remnants who settled in Thailand after 1949, Mae Salong developed a hybrid identity — a Chinese cultural enclave growing tea and coffee at altitude. Mae Salong's arabica is grown alongside oolong tea and reflects the area's unusual history.

Growing conditions in the northern highlands

Oliang: traditional Thai coffee culture

While the northern highlands produce specialty arabica for export and urban cafés, the dominant form of coffee in everyday Thai life — particularly in street markets, traditional restaurants, and older city neighbourhoods — remains oliang^[3].

The blend: Oliang is not purely coffee. Traditional blends combine:

• Dark-roasted robusta coffee (the base)
• Roasted corn (adds sweetness, body, and extends the blend)
• Roasted soybeans or sesame seeds (depth and thickness)
• Cardamom (aromatic spice, the defining flavour note)
• Sometimes: palm sugar, rice, or other additions depending on regional tradition and the roaster's recipe

Proportions are proprietary — old-style Thai coffee roasters guard their blend ratios. The result is a coffee blend that does not taste purely of coffee: the cardamom is immediately apparent, the corn adds a gentle sweetness beneath the bitterness, and the overall profile is more complex and spiced than a pure-robusta brew.

The brewing method: Oliang is brewed through a tungdtom (ถุงต้ม) — a cloth sock filter attached to a metal ring handle. The sock is similar in principle to a cloth filter for pour-over, but the traditional usage involves immersing the sock in hot water in a kettle or pot and allowing the grounds to steep, then lifting and draining. Some vendors use the sock in a percolation style, pouring water through grounds packed in the sock into a pot below.

The result is a very strong, dark, thick brew — sometimes described as resembling strong tea in colour but with an intense, spiced coffee flavour.

Serving:

• Oliang: Strong coffee extract poured over ice in a glass, black or with a small amount of sugar
• Kafae boran (กาแฟโบราณ / traditional coffee): Oliang with sweetened condensed milk poured in — the standard order for most Thai coffee drinkers
• Ka nom wan (added evaporated milk): Both condensed and evaporated milk are added for a creamier, less sweet variation

The condensed milk is added to the glass first — pooling at the bottom — and the hot strong coffee is poured over it, creating a visual gradient before stirring.

Chinese roots of Thai coffee culture

The oliang tradition reflects the significant cultural influence of Hokkien Chinese immigrants in Thailand, particularly in Bangkok and the south^[2]. Chinese communities established the first coffee shops (โรงน้ำชา, rong nam cha — literally "tea room") in Thai cities from the late 19th century. These shops served both tea and coffee, and the coffee culture they brought was from southern China and the Straits Settlements (Penang, Singapore) — which itself had a distinctive tradition of spiced robusta coffee with condensed milk.

The cloth sock filter, the condensed milk service, the spiced blend — all are characteristic of the Nanyang (南洋, "South Seas") coffee tradition common across Southeast Asian Chinese communities. Thai oliang is closely related to Malaysian and Singaporean kopi culture.

Modern Thai specialty scene

Since the late 2000s, Bangkok has developed a significant specialty coffee scene, initially concentrated around Silom and Thonglor and now spread more widely. Thai specialty cafés serve single-origin Doi Chang and Doi Tung pour-overs and espresso drinks alongside — and sometimes instead of — oliang.

Thailand has produced World Barista Championship competitors and hosted specialty coffee events. The younger urban demographic in Bangkok increasingly drinks arabica specialty coffee from both domestic and international origins.

This does not replace the oliang tradition — street vendor oliang and condensed milk coffee remain dominant in volume — but the two traditions now coexist in Thai urban coffee culture in a way that was not true 20 years ago.

The honest summary

Thai coffee exists in two distinct traditions with limited overlap. In the northern highlands — Doi Chang, Doi Tung, Mae Salong — arabica is grown at 1,100–1,600 metres by hill tribe communities, many of whom transitioned from opium cultivation through the Royal Project beginning in the 1970s. Doi Chang has become internationally recognised for its specialty profile. Separately, traditional Thai coffee culture is centred on oliang — a spiced robusta blend with corn, soybeans, and cardamom rooted in Hokkien Chinese immigrant café culture — brewed through a cloth sock and served iced with condensed milk. Contemporary Bangkok has a growing specialty café scene that draws on both domestic origins and international coffees.