Development of sugar-free functional maize extrudates enriched with spirulina and Peruvian carob fruit

Rimari-Barzola R.; Encina-Zelada C.R.; Casavilca-Hernandez D.; Moyano-Rojas S.; Huamán-Meza K.; Loayza-Salazar S.; Saldaña E.; Carvalho C.W.P.; Comettant-Rabanal R. · International Journal of Food Science and Technology (2026) · DOI: 10.1093/ijfood/vvaf287

Resumen

To develop functional extrudates free from added sugars, spirulina powder (SP) and Peruvian carob fruit (CFP) were incorporated into maize-based formulations using a D-optimal mixture design and a twin-screw extrusion system. Chemical composition, total phenolic compounds (TPC), and tannins (TCT) were determined, alongside antioxidant capacity assessed by ABTS and DPPH assays. The technological properties evaluated included the sectional expansion index (SEI), bulk density (BD), water absorption index (WAI), and water solubility index (WSI). Textural parameters such as number of cells (Nsr), fracturability (Fsr), puncture force (F), and crispness work (Wc), as well as pasting properties, were also measured. Sensory evaluation was carried out using the TCATA test, and the phenolic compound profile by HPLC of the optimal extrudates was quantified. The incorporation of SP and CFP significantly improved the nutritional and functional profile of the extrudates, increasing minerals (36%–85%), protein (15%–56%), TPC (102%–220%), and TCT (344%–752%). Antioxidant capacity increased by 52%–105% for ABTS and 326%–527% for DPPH. Their synergistic effect influenced the expansion, hydration, texture and pasting properties. The T8 extrudate with the lowest spirulina content, showed the best technological expansion properties, whereas the T5 extrudate, with the highest spirulina and Peruvian carob fruit content, stood out for its superior nutritional and functional profile. Optimised spirulina and carob levels preserved consumer acceptance, driven by a “crunchy” texture and clean flavour. Both optimum samples showed remarkable increases in phenolic acids (gallic, syringic, ferulic, protocatechuic) and 7–8 times higher flavonoids, including rutin, as well as (−)-epicatechin. © The Author(s) 2026. Published by Oxford University Press on behalf of the Institute of Food Science and Technology.

Instituciones: Universidad Nacional Agraria La Molina; Universidad Privada San Juan Bautista; Universidad Nacional de Moquegua