Formulation and comprehensive characterization of raspberry jelly candies enriched with raspberry puree and black carrot concentrate: effects of matrix composition and packaging materials

Introduction The growing consumer demand for healthier confectionery has accelerated the reformulation of traditional jelly candies using natural and functional ingredients. This study aimed to develop raspberry-flavoured jelly candies with natural components such as black carrot concentrate and raspberry puree, using a pectin–gelatin gelling system. Methods To investigate the role of matrix composition, the dry matter content (87.2–92.7%) and the pH level (3.00–3.53) were systematically varied. The newly formulated candies were characterized in terms of physicochemical, optical, structural, thermal, and functional properties. To identify the most suitable packaging system for the developed candies, the thermal, mechanical, and barrier properties of three packaging films (white metallized BOPP, orange BOPP/LDPE, and transparent PET/LDPE) were investigated. Results and discussion The results revealed that the dry matter content and packaging light-shielding ability were the two dominant factors governing the product quality. Increasing the dry matter to 92.7% significantly lowered water activity to 0.72–0.74, raised the glass transition temperature (51 °C–53 °C), increased matrix hardness and antioxidant activity. The opaque white and orange films provided critical light-shielding that kept color changes minimal (Δ E * ≤ 2.36), whereas the transparent film allowed severe photograph-oxidative color degradation (Δ E * > 3). Furthermore, the white film’s aluminium layer successfully minimized moisture migration by achieving the lowest water vapor permeability coefficient ( P  = 9.2 × 10 –10 g/(g · atm · cm 2 · s)). Future research will evaluate the long-term stability of the newly developed formulations during extended storage, while optimizing their composition with novel natural ingredients to ensure enhanced quality, stability, and sensory acceptability.