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Transformación de la textura del gel mediada por la temperatura en fideos de almidón: con respecto a la temperatura
Hongxiao Liu1,2, Qing Hu1,2, Sha Yang2
1College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, China.
Gels (Basel, Switzerland)
|August 28, 2025
Resumen
La congelación de fideos de almidón de patata (PSN) cerca de su temperatura de transición al vidrio (Tg) optimiza la textura. Los fideos congelados a -3 °C mostraron una mayor dureza, cohesión y microestructura deseable, mejorando el procesamiento de alimentos congelados.
Área de la Ciencia:
- Ciencias de la alimentación
- Ciencias de los materiales
- Química Física
Sus antecedentes:
- Los fideos de almidón de patata (PSN) son alimentos asiáticos sin gluten, principalmente geles de almidón de alta concentración.
- La textura del gel de almidón está significativamente influenciada por las condiciones de procesamiento, como la congelación.
- Comprender el impacto de las temperaturas de congelación, especialmente alrededor de la temperatura de transición de vidrio (Tg), es crucial para optimizar la calidad de PSN.
Objetivo del estudio:
- Investigar los efectos de las temperaturas bajo cero en la textura y la microestructura de los fideos de almidón de patata (PSN).
- Determinar el rango óptimo de temperatura de congelación, en particular en relación con la temperatura de transición al vidrio (Tg), para preservar la calidad de la PSN.
- Para aclarar los mecanismos detrás de los cambios de textura en PSN durante la congelación.
Principales métodos:
- Determinación del punto de congelación (-1 °C), de la temperatura de sobreenfriamiento (-4,5 °C) y de la temperatura de transición al vidrio (Tg", -3,1 °C) de las PSN frescas.
- Congelación sistemática de PSN a varias temperaturas, centrándose en el rango Tg'.
- Análisis de la textura de la PSN (dureza, adherencia, elasticidad, cohesión, masticabilidad, resistencia) y de la microestructura después de la congelación.
Principales resultados:
- La congelación alteró significativamente la textura de la PSN, reduciendo la adherencia y aumentando la dureza.
- Los fideos congelados a -3 °C (más cercanos a Tg) exhibieron propiedades de textura óptimas: mayor dureza (14,065.77 g), elasticidad (0,98), cohesión (0,93), masticabilidad (11,971.06) y resistencia (0,84), con una adherencia mínima.
- PSN congelado cerca de Tg mostró una textura superior, una sección transversal sólida continua y una superficie densa, atribuida a la transformación inversa del almidón, una alta movilidad de la cadena de almidón y cristales de hielo más pequeños.
- La congelación a -3 °C durante 24 horas produjo la textura más compacta y deseable.
Conclusiones:
- La temperatura de transición de vidrio (Tg) juega un papel crítico en la formación de la textura de los geles de almidón durante la congelación.
- La congelación de PSN a temperaturas cercanas a su Tg mejora significativamente su calidad textual y su integridad microestructural.
- Estos hallazgos proporcionan información valiosa para optimizar el procesamiento congelado de alimentos a base de gel de almidón, incluido el PSN.
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