Volume 25, Issue 2 (2-2023)
Abstract
Malt beverage is one of the most popular drinks in the world. Recently, consumption of non-alcoholic beverages has expanded significantly in many countries. The permitted level of alcohol in malt beverage is less than 0.5% by Iranian National Standards. In this study, a method was developed to determine ethanol content in malt beverages by FTIR, equipped with Horizontal Attenuated Total Reflectance (H-ATR). Here, the Limit Of Detection (LOD) and Limit Of Quantification (LOQ) were 0.07% and 0.23%, respectively. The correlation coefficient of calibration curve was higher than 0.999. Fifty commercial malt beverages from six brands (five Iranian and one imported brand) and three types of flavored malt beverage (classic, equatorial, and lemon) were assessed. The average detected ethanol amount in samples was 0.19%, varying between 0.00-1.47percent. The results showed that the amount of ethanol in lemon malt drinks was more than the maximum permitted limit; that could be attributed to the usage of ethylene glycol for extraction of lemon flavor.
Volume 27, Issue 3 (3-2025)
Abstract
Organic acids remarkably affect the microbial control, stability, and organoleptic characteristics (flavor, color and aroma) of beverages. This study focuses on the determination of organic acids, including oxalic, citric, tartaric, malic, succinic, lactic, fumaric, acetic, propionic, and gallic acid, in 100 commercial malt beverages from different brands (five Iranian and five various imported brands) and flavored variants (classic, pomegranate, peach, tropical and lemon). In addition, the contents of total phenols, total flavonoids, ascorbic acid, and free amino acids were measured to assess the overall composition. Liquid Chromatography (LC) was employed to develop a method for analyzing the organic acids, while spectrophotometric techniques were used for quantifying other bioactive compounds. The results revealed significant variations in the organic acid profiles, with succinic acid being the most abundant, while tartaric acid was absent in all samples. Chemometrics technique (PCA method) was applied to classify the results. The results show that PCA can classify the malt drinks based on the additive values with a very high precision. To improve the quality control of malt beverages, some extra assessments, like organic acids and free amino nitrogen determination, should be considered for Iranian National Standard.
