unveiling ethanol concentrations in traditional beverages from lombok island using gc-fid method

Tuak, tuak manis, and brem are traditional beverages produced through the fermentation of specific plants on lombok island, indonesia. evaluating the alcohol content in these beverages is crucial for ensuring their halal status and safety for muslim consumers. this research aims to determine the alcohol concentration of traditional drinks obtained from various tourist locations in mataram city, lombok island, indonesia. alcohol levels were analyzed after simple distillation using the gc-fid method, validated through parameters such as accuracy, linearity, selectivity, limits of detection (lod), limits of quantitation (loq), and recovery. the results showed an rsd value of 1.6292%, a linear regression equation of y = 1102x + 11.103, a regression coefficient (r²) of 0.9997, selectivity (rs) > 1.5, an lod of 0.0256%, an loq of 0.0854%, and a recovery rate of 102.83%. these findings demonstrate that the validation parameters are robust and suitable for determining alcohol content. the measured alcohol concentrations in the traditional beverages were as follows: tuak contained 1.43±0.21% to 3.50±0.12%, brem contained 1.32±0.14% to 3.10±0.10%, and tuak manis contained 0.0004±0.0003% to 0.2361±0.0081%. significant differences in alcohol content were observed across sampling locations (p < 0.05, one-way anova). all samples of tuak and brem contained alcohol levels exceeding 0.5%, while tuak manis had ethanol concentrations less than 0.5%. this information is expected to raise public awareness regarding the consumption of halal and safe traditional beverages.