Quality parameters, market challenges, and consumption trends of traditional palm brandy

Abstract

Tua-sabu is a traditional alcoholic beverage with a long-standing history dating back to ancient times, recognized and valued as part of the sociocultural and economic heritage of Timor-Leste. It is produced from the sap of various palm species, such as akadiru (Borassus flabellifer L.), tua-metan (Arenga pinnata (Wurmb) Merr), nuu (Cocos nucifera L.), and tua-tali (Corypha utan Lam.), through sap extraction, spontaneous fermentation, and simple distillation. This study aimed to determine the alcohol content (%ABV) and identify volatile organic compounds (VOCs) in each distillation fraction of tua-sabu across all palm species, produced and commercialized in various regions of Timor-Leste. A total of 98 fractions were analyzed, comprising tua-ulun (head), tua-klaran (heart), and tua-ikun (tail), collected from multiple municipalities and representing three different collection points: directly at production sites, small grocery stores, and local markets or fairs. Ethanol content was determined by liquid chromatography (LC), VOCs were identified using gas chromatography (GC), and data analysis was performed using principal component analysis (PCA). The results showed that the tua-ulun fractions from all palm species, regions, and collection points had ethanol concentrations ranging from 22.3% to 61.0% v/v, while tua-klaran ranged from 10.1% to 30.5% v/v, and tua-ikun from 6.7% to 24.0% v/v. Notably, some tua-ulun fractions exhibited lower alcohol content than certain tua-klaran or even tua-ikun fractions. Despite significant variation in ethanol concentrations among fractions, many samples exhibited similar levels, even when collected from different regions, producers, palm species, or points of sale. These differences and similarities are primarily attributed to factors such as the origin of the raw materials, the types and hygienic conditions of storage containers, and variations in processing methods across the production and supply chain, including the mixing of different fractions prior to sale. The volatile compound analysis revealed that each distillation fraction contained a distinct profile of VOCs, which may reflect differences in geographical origin, palm species, or distillation processes. The identified chemical groups included alcohols, acids, aldehydes, esters, ethers, ketones, and other organic compounds that contribute to the beverage’s aroma and flavor. However, when present in excess, these compounds can negatively alter the chemical profile, leading to consumer rejection and potential health risks. The absence of national quality standards and the lack of implementation of Good Manufacturing Practices (GMP) further contribute to the potential unsafety of the beverage for human consumption. Therefore, strict control over the production and distribution chain, particularly avoiding the mixing of distillation fractions, is essential to improve the quality of tua-sabu and reduce associated risks to public health.