Oleang has the unique aroma, a combination of a coffee aroma and the special roast and smoky notes from high roasted grains and seeds
The name is derived from the Teochew dialect, the language spoken by the majority of Thai Chinese, indicating that oliang is from China. The word “o” means “black” and “liang” means “cold”. Oliang is black iced coffee.
Oleang is prepared from the mixture of robusta coffee, brown sugar, and various grains and seeds, generally corn, soybean, rice and sesame. There is no specific formulation or document written about the ingredients of oleang. The amounts of coffee in the formulations printed on the product labels can be varied from 20 to 80%.
There is no specific recipe for the oleang mix but corn and soybean are the two other major components. The other grain and seed ingredients can vary greatly. Oleang has the unique aroma, a combination of a coffee aroma and the special roast and smoky notes from high roasted grains and seeds. If you try to prepare Thai coffee drink from robusta coffee alone, it will fail to mimic the unique roasted aroma of oleang.
During WWI when money was tight and coffee was expensive. Inexpensive and common grains were added to the coffee beans during the roasting process to make the coffee go further. The drink that now consisted of soy beans, brown rice, sugar, salt, tamarind seeds and even butter was then filtered through a ‘sock filter’ or a fabric bag, poured over with boiling water and left to steep. Cheap, tasty and accessible it was the answer to the coffee shortage and those locals needing a morning pick-me-up before work.
You’d find this mainly at street stalls and some noodle shops; they also invariably offered Thai iced tea – ชาเย็น (cha yen). The coffee is made by putting the grounds in a coffee “sock” and seeping it in water, much like making tea; sweetened condensed and evaporated milk are then added… It was, and is – it’s still widely available in markets – easy to find such stalls by looking for the characteristic metal pots with the coffee socks in them used to brew the coffee and also by the stacks of condensed milk at the front of the stall.
Thai coffee is usually rather bitter as it is frequently over extracted – most likely in an attempt to make the grounds stretch further and save money. This bitterness is countered by sweetened condensed milk, evaporated milk and brown sugar which are added to the hot liquid and poured over a handful of ice-blocks.
On a hot, humid day this sweet, caffeinated traditional drink is relished by tourists and locals alike.