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Connective tissue (CT) proteins in jumbo squid (Dosidicus gigas) play an important role because they are the responsible for the union between various cells; hence, there is a close relationship between their functions and muscle firmness during ice storage. In this study, the thermal resistance and solubility of the CT extracted from the fins, mantle and arms of jumbo squid during ice storage (20 days) was evaluated. The CT was fractionated based on solubility [NaCl‐soluble (SSCT) and insoluble (ICT)]. The solubility of the CT was affected during ice storage. An increase in the thermal resistance of the SSCT after 10 days with a subsequent decrease was found in the mantle. Furthermore, the ICT was thermally more resistant than the SSCT in all the anatomical regions. Finally, the electrophoretic profile revealed that structural changes occurred, causing changes in its solubility, due to an increase in the thermal resistance. Practical Applications Jumbo squid (Dosidicus gigas) is an important seafood resource in Mexico, which is commercialized primarily iced and fresh‐frozen. Its muscle connective tissue (CT) has different physicochemical characteristics that differ from other seafood products; it is thermally more resistant and might be responsible for the textural changes during ice storage. Moreover, specific studies about the behavior of CT proteins in such organism may result in improved post‐catch management of jumbo squid muscle, focused on the processing of the species in the food industry or anywhere that CT proteins are used as raw material. The main objective of this research is to investigate solubility changes and thermal resistance of CT proteins of iced jumbo squid mantle.

The starch granules of complete and substituted triticale genotypes were analyzed for morphology and size distribution using scanning electron microscopy (SEM) and laser diffraction, respectively. A quantitative comparison of total carbohydrate, starch, and amylose contents was also performed. The results showed that the complete triticales contained 8.8% more total carbohydrate content and 13.8% more starch content than the substituted ones. No significant differences in the average amylose content (22.8%) were observed between the two sets of triticales. However, the A-and B-type starch granules of the substituted triticales showed significant differences in amylose content. Starch granule distribution profiles showed that the sizes of the A-and B-type starch granules of complete triticales were larger (in the range of 18-41 μm and 2-13 μm, respectively) than those of substituted triticales (in the range of 8-38 μm and 0.5-6 μm, respectively). This study demonstrated that the starch in triticale genotypes differs in physicochemical properties.Keywords: triticale; SEM; laser diffraction; starch; amylose; carbohydrate Se analizaron los gránulos de almidón de genotipos de triticales completos y sustituidos en morfología y distribución de tamaño utilizando microscopía electrónica de barrido (SEM, por sus siglas en inglés) y difracción láser, respectivamente. Se realizó una comparación cuantitativa del contenido de carbohidratos totales, almidón y amilosa. Los resultados mostraron que los triticales completos contienen 8,8% más en contenido de carbohidratos totales y 13,8% más de contenido de almidón que los triticales sustituidos. No se observaron diferencias significativas en el contenido de amilosa (promedio 22,8%), sin embargo, los gránulos de almidón tipo-A y tipo-B de los triticales sustituidos mostraron diferencias significativas en el contenido de amilosa, pero no los respectivos gránulos de los triticales completos. El análisis del perfil de distribución de los gránulos de almidón mostró que los gránulos de almidón tipo-A y tipo-B de los triticales completos son de mayor tamaño (rango de 18-41 μm y 2-13 μm, respectivamente) que el de los triticales sustituidos (rango de 8-38 μm y 0,5-6 μm, respectivamente). Se concluye que el almidón de los genotipos de triticales difieren en las propiedades fisicoquímicas estudiadas.

Cereal Chem. 93(1):64-70The present work was carried out to make a comparison between the starch debranching enzyme activity and the synthesis of total carbohydrates, starch, amylose, and amylopectin in developing kernels of two sets of triticales differing in genome composition (complete and substituted triticales). The results showed that the carbohydrate and starch accumulation observed in both genotypes of triticales increased rapidly at the early stage, reaching the maximum at the medium stage and decreasing slightly or remaining relatively constant at the last stage of kernel development. At the end of the development stage, the mature grains of complete and substituted triticales accumulated 62.5 and 54.6% starch, respectively. Both sets of triticales showed the same amylose accumulation profile as well as degree of polymerization; however, at the maturity stage there was a small but significant difference between the two sets. The final polymerization values of amylose chains in mature seeds of complete and substituted triticales were DP 1,549 and 1,313. A and B 1 amylopectin chains of the complete triticales were approximately 19 and 33% shorter than those of the substituted triticales. The complete triticales showed higher isoamylase and pullulanase activities than the substituted triticales, which coincided with the highest starch and amylose contents observed in kernels under development. The results of this study demonstrate that the synthesis of starch differs between the triticale genotypes used in the study, which influences their chemical structure and physicochemical properties. † Corresponding