CIDCA   05380
CENTRO DE INVESTIGACION Y DESARROLLO EN CRIOTECNOLOGIA DE ALIMENTOS
Unidad Ejecutora - UE
capítulos de libros
Título:
Effect of mucilage extraction on the functional properties of chia meals
Autor/es:
MARIANELA I. CAPITANI; SUSANA M. NOLASCO; MABEL C. TOMÁS
Libro:
Food Industry
Editorial:
InTech
Referencias:
Lugar: Rijeka; Año: 2012; p. 421 - 437
Resumen:
Salvia hispanica L. is an annual herbaceous plant that belongs to the Lamiaceae family. Chia, together with corn, beans, and amaranth, was an important food crop for pre-Columbian civilizations in America. Chia seeds comprise about 25-38% oil by weight, with the highest percentage of -linolenic acid (~60%) compared to other known vegetable species, and they are a good natural source of antioxidants, proteins, vitamins, minerals and dietary fiber. They also contain a complex carbohydrate of high molecular weight (mucilage, a type of soluble dietary fiber) which is of interest not only from the nutritional point of view, but also as a thickening agent in the food industry. The chia meal is a good source of proteins and dietary fiber, and it exhibits interesting physiological and functional properties for its use in health and the food industry. Knowledge about the functional properties of chia seeds, such as water holding, absorption and adsorption capacity, as well as those linked to the affinity for lipid components is useful for the food industry because during their processing some modifications can occur that must be taken into account according to the usage of the final product and its marketing conditions. The aim of this study was to compare the functional properties of meals derived from chia seeds with and without mucilage. Commercial chia seeds used in this study were obtained from Salta, Argentina. The meals were obtained after the oil extraction with solvent in a Soxhlet apparatus (n-hexane, at 80 °C for 8 h) of previously-ground chia seeds (Hs) and of seeds which previously had the mucilage extracted by freeze-drying and subsequent sieving process (Hsm). The proximate composition of the meals (moisture, crude fiber, ash, protein, residual oil and nitrogen-free extract) was studied. Total dietary fiber (TDF), soluble dietary fiber (SDF) and insoluble dietary fiber (IDF) were also determined. Functional properties such as water absorption capacity (WAbC), organic molecule absorption capacity (OMAC), water-holding and oil-holding capacity (WHC and OHC, respectively), emulsifying activity (EA) and emulsion stability (ES were evaluated. The stability of the emulsion over storage time was also studied using a vertical scan analyzer (Quick Scan) by measuring the backscattering of light. The Hs and Hsm meals were characterized by a high content of protein (41.36±0.28 and 42.43±0.71% respectively) and crude fiber (27.57±0.07 and 27.75±0.97% respectively). In addition, both meals presented a high content of TDF (46.06±0.86 and 47.13±0.17% in Hs and Hsm, respectively), being the content of SDF statistically higher (p<0.05) in Hs (4.93±0.65 and 1.51±0.24% in Hs and Hsm, respectively). Regarding the functional properties, the Hs showed statistically higher values (p<0.05) than Hsm for WAbC (6.45 and 4.79% respectively) and ES (60.0 and 53.3% in Hs and Hsm, respectively), while the opposite behavior was observed for OHC (2.94 and 2.03%) and OMAC (2.22 and 1.64% in Hsm and Hs, respectively). By the Quick Scan, a similar behavior was observed for ES, because even though both meals obtained a high initial emulsifying activity (backscattering 66.3 and 62.2% in Hs and Hsm, respectively), the emulsion prepared with the meal without mucilage presented a significant decrease in stability over the analyzed time (60 min) (backscattering 50.4%), whereas the stability of the emulsion corresponding to the meal with mucilage remained mostly constant (backscattering 59.5%). These results show the potential use of both chia meals in the food industry, for example in the manufacture of bakery products, powdered beverages, yogurts, ice-creams, sauces and creams. As regards the formulation of stable emulsions, meal with mucilage is recommended for use due to its role as a thickening agent.