Abstract
The agri-food sector faces the challenge of valorizing by-products and reducing waste. The frozen pumpkin industry generates substantial amounts of by-products rich in nutritional value, especially β-carotene. This study evaluates the nutritional and physical impact of incorporating pumpkin pulp flour (dehydrated and freeze-dried) obtained from by-products into cracker formulation. Crackers were prepared by replacing 10% and 20% of wheat flour with pumpkin flour, assessing the effects based on drying method. Physical parameters (expansion, color, and texture parameters) were measured, in the dough and in the baked products. Furthermore, β-carotene content was analyzed by HPLC-DAD, antioxidant capacity was measured with DPPH, ABTS, and ORAC, and total phenolic content was evaluated with the Folin-Ciocalteu method. Proximate composition and mineral content were also analyzed. Additionally, a preliminary sensory evaluation was conducted with 50 untrained consumer judges to assess acceptability of external appearance, texture, and taste. The inclusion of pumpkin flour significantly increased β-carotene content (up to 2.36 mg/100 g), total phenolics, and antioxidant activity of the baked crackers. Proximate analysis showed a marked improvement in fiber content and a slight reduction in energy value compared to wheat flour. Mineral analysis revealed that pumpkin flours exhibited significantly higher levels of K, Ca, Mg, and P, with improved but not always statistically significant retention in the final crackers. Freeze-dried flour retained more bioactive compounds and enhanced color. However, it also increased cracker hardness, particularly with dehydrated flour. Only the 10% freeze-dried formulation showed mechanical properties similar to those of the control. Sensory analysis indicated that all formulations were positively accepted, with the 10% freeze-dried sample showing the best balance in consumer preference across all evaluated attributes. Frozen pumpkin by-products can be effectively valorized through their incorporation into bakery products such as crackers, enhancing their nutritional and functional profile. Freeze-drying better preserves antioxidants and β-carotene, while a 10% substitution offers a balance between nutritional enrichment and technological performance and sensory acceptability.