Ćupter: Solar drying and scale-up potential of a traditional grape-based snack from Bosnia and Herzegovina

Traditional food products (TFPs) play important socio-economic roles in every culture, supporting rural areas’ development, diversification, and sustainability. However, factors such as globalisation and armed conflicts have contributed to the degradation of cultural knowledge, including awareness of TFPs, even within local communities. Ćupter is a traditional jelly-like dessert from Bosnia and Herzegovina (BiH), prepared from wheat flour or semolina and fresh grape juice, and traditionally dried in the sun. Due to its composition, ćupter could be similar in nutritional value and texture to modern healthy snacks as fruit leather, suggesting potential for recognition as a TFP and as a functional food. This study investigated the potential of ćupter for commercialisation by examining consumer attitudes, nutritional characteristics, and the impact of different drying methods on its sensory and microbial quality. Consumer survey conducted in BiH showed that 64.8% of respondents were familiar with ćupter, with the main reasons for consumption being tradition (94.1%), health benefits (70.3%), and taste (55.9%). The ćupter is mostly homemade and rarely bought in shops with local food. Despite its widespread consumption, only 26 % of respondents had deeper knowledge about its preparation. Experimental analyses revealed that solar drying is a more reliable method for larger-scale production than traditional open sun drying, without compromising sensory or microbial quality. Nutritional analysis confirmed that ćupter is a valuable source of energy and minerals (Fe, K, Mn, P, Zn), comparable to popular fruit rolls and snack bars. Overall, ćupter shows strong potential for commercialisation, which could not only preserve and promote an important element of cultural heritage but also support local producers and contribute to the growth of rural tourism.