Nutritional Variation Within and Across Standardized Beverage Categories in Korean Franchise Coffee Shops

Franchise coffee shops now offer an increasingly diverse beverage portfolio with substantial variation in nutritional composition. However, cross-brand comparisons remain difficult because products are commonly organized according to proprietary menu names and marketing concepts rather than standardized nutritional attributes. This study developed and applied a standardized beverage classification framework based primarily on beverage ingredients and preparation characteristics to examine nutritional variation both within and across beverage categories. Nutritional information for 3586 beverages from 31 major franchise coffee brands was obtained from official websites. Beverages were systematically assigned to 10 standardized categories according to their ingredients and preparation methods. Serving size and per-serving contents of energy, total sugar, protein, saturated fat, sodium, and caffeine were analyzed and compared across beverage categories and between matched hot and iced products. All nutritional variables differed significantly among beverage categories (all p < 0.001). However, substantial within-category variability was also observed. For example, total sugar content among coffee beverages ranged from 13.0 g/serving at the 25th percentile to 48.0 g/serving at the 90th percentile. The findings demonstrate substantial nutritional variation both between and within standardized beverage categories, indicating that beverages sharing similar ingredient and preparation characteristics do not necessarily have similar nutritional profiles. The proposed framework provides a transparent and reproducible taxonomy for organizing heterogeneous beverage products across brands and may facilitate nutritional surveillance and comparative research.