Yeast & Fermentation

Thailand's major beers are bottom-fermented lagers. The yeast works at around 8 to 12°C and settles at the bottom of the tank once fermentation is complete. In a country with relentless heat, this is only possible with cooling systems; a longer cold-conditioning period follows the main fermentation.

During fermentation, yeast converts sugar into alcohol and carbon dioxide. Bottom-fermenting yeasts work more slowly and cleanly than top-fermenting ones, which is why lagers like Singha or Chang taste clear and lean. The beer then continues to mature cold and clarify before being filtered and bottled.

What long held back small brewers in Thailand wasn't brewing skill but the law. Under the Liquor Act of 1950, beer could only be brewed in a factory producing more than one million litres a year. A brewpub — a restaurant with its own brewery — needed to produce at least 100,000 litres a year and was not allowed to bottle its beer.

Many craft brewers worked around this by having their recipes brewed abroad and then importing them. On 2 November 2022, a new ministerial regulation on alcohol production came into force. It replaced the 2017 version and dropped the requirement to show at least ten million baht in capital.

In 2025, parliament passed a further relaxation: the Community Alcohol Act, Excise Act No. 2 of 2568 BE (Buddhist Era), makes it easier for small producers to obtain a licence. How this plays out in practice will only become clear over the coming years. Until then, the market remains in the hands of Boon Rawd and ThaiBev, who have spent decades building their own breweries, cold chains and distribution networks.