Resumen El almidón resistente (AR) es una fracción del almidón no digerible por las α-amilasas y a diferencia de la fibra dietética, el AR es fermentado en el colon promoviendo beneficios en la salud. Dentro de los diferentes tipos de AR, el tipo 3 (AR3) se obtiene por autoclaveado y sin el uso de agentes químicos. El objetivo de este estudio fue obtener AR3 a partir de avena y evaluar su efecto a diferentes concentraciones (0, 5, 10, 15 y 20 %, p/p) sobre las propiedades reológicas de la masa, propiedades de textura de las galletas y su aceptabilidad sensorial. El análisis de perfil de textura (TPA) evidenció un incremento en la fracturabilidad, dureza, adhesividad y gomosidad. La incorporación de AR3 incrementó el módulo elástico (G´) y viscoso (G´´) en comparación con la masa control. Todos los tratamientos presentaron comportamiento elástico (G´ > G´´). La dureza en las galletas aumentó con la concentración de AR3, con valores de ≈ 8 N (control) hasta 20 N (AR3-20 %). Las pruebas sensoriales no fueron significativas entre tratamientos, aunque las galletas AR3-20 % tuvieron mayor preferencia. La adición de AR3 en la masa provocó cambios funcionales y de textura significativos que afectaron positivamente los atributos de calidad de las galletas.

Abstract Resistant starch (RS) is a portion of starch that is not digestible by α-amylases and unlike dietary fiber, RS is fermented in the colon, promoting health benefits. Among the different types of RS, type 3 (RS3) is obtained by autoclaving and without chemical agents. The objective of this work was to obtain RS3 from oats and to evaluate its effect at different concentrations (0, 5, 10, 15 and 20 % w/w) on the rheological properties of the dough, textural properties of the cookies and their sensory acceptability. Texture profile analysis (TPA) showed an increased fracturability, hardness, adhesiveness and gumminess. The incorporation of RS3 increased the elastic (G’) and viscous (G’’) modulus compared to the control dough. All treatments showed elastic behavior (G’ > G’’). Hardness in cookies increased with RS3 concentration, with values from ≈ 8 N (control) to 20 N (RS3 - 20 %). Sensory tests were not significant between treatments, although RS3-20 % cookies had a higher preference. The addition of RS3 in the dough caused significant functional and textural changes that positively affected the quality attributes of the cookies.

ABSTRACT Intensive horticultural crop production usually involves challenges from excessive application of fertilizer, mainly nitrogen (N). The effect of N fertilizer on the fruit quality and antioxidant status of two cherry tomato cultivars (Caballero and Victoria) under greenhouse conditions was performed. Nitrogen treatments were applied ranging from conditions comprising deficiency to toxicity (0, 15, 30, 45 and 60 mmol∙L-1). Yield, weight, diameter, fruit quality, phenols, flavonoids, lycopene, ascorbic acid and antioxidant capacity were measured at physiological maturity of the fresh tomato fruits. N treatment with 30 mmol∙L-1 produced the highest yield, fruit weight, firmness and diameter in both cultivars. However, increasing N from 30 to 60 mmol∙L-1 increased the concentration of phenolics, flavonoids, and antioxidant capacity by 50, 125 and 33% in ‘Caballero’ tomatoes and by 60, 95 and 24% in ‘Victoria’ tomatoes, respectively. Lycopene content increased with increasing N doses (45 and 60 mmol∙L-1) for ‘Caballero’ tomatoes, while vitamin C decreased as N concentration increased, suggesting that ascorbic acid acts by protecting against oxidative stress in tomato. The present work shows how N fertilization considerably influences yield and quality of tomatoes, as well as nutritional and healthy values.