Biolixiviación y su impacto en el rendimiento de aceite de semillas de Cucurbita foetidissima Kunth en dos métodos de extracción

The buffalo gourd (Cucurbita foetidissima Kunth) is a plant with a wide potential for use. We sought to determine optimal conditions to extract oil from their seeds, exposing them to previous treatment of cell wall degradation using a cellulolytic fungus to increase oil yields during extraction. The fungus Aspergillus niger, classified as GRAS, was induced in carboxymethylcellulose to promote production of cellulases and then inoculated a medium formulated with crazy gourd seed as the sole source of carbon, plus micronutrients. Hydraulic pressing and Soxhlet method were used for extraction. The best conditions were: pH 7 at 25 °C for 96 h, according to the Tukey test (p ≤ 0.01). With the Soxhlet method, a yield of 34% was obtained for the untreated sample and 43.76% for the biolix spill, and in the press was 24.44% for the non-biowashed sample and 27.54% for the sample with treatment.La calabacilla loca (Cucurbita foetidissima Kunth) es una planta con amplio potencial de aprovechamiento. Se buscó determinar condiciones óptimas para extraer aceite de sus semillas, se les sometió a tratamiento previo de degradación de pared celular utilizando un hongo celulolítico para incrementar los rendimientos de aceite durante la extracción. El hongo Aspergillus niger, clasificado como GRAS, fue inducido en carboximetilcelulosa para promover producción de celulasas y después inocular un medio formulado con semilla de calabacilla loca como única fuente de carbono, más micronutrientes. Se utilizó prensado hidráulico y método Soxhlet para la extracción. Las mejores condiciones fueron: pH 7 a 25 °C por 96 h, según la prueba de Tukey (p ≤ 0.01). Con el método Soxhlet se obtuvo rendimiento de 34% para la muestra no tratada y 43.76% para la biolixiviada, y en el prensado fue de 24.44% para la muestra no biolixiviada y 27.54% para muestra con tratamiento

Effect of oxidation and crosslinking on functional, rheological and thermal properties of oat and apple starches

Oat (Oa) and apple (Ap) starches were isolated and chemically modified by oxidation with 10% NaOCl to obtain oxidized starches (OOa and OAp), followed by cross-linking with a mixture of 5.6 g of sodium tripolyphosphate and 11 g of sodium trimetaphosphate to obtain doubly modified starches (OCOa and OCAp). In the native and modified starches, the functional properties (swelling power and solubility, and freeze-thaw stability) and thermal and rheological properties (steady-state flow curves and paste formation profile) were evaluated. The swelling power of native and double modified starches varied from 57 to 86 g/g and the solubility from 0.8 to 6.0 g/100 g, these variables increased as the study temperature increased; the increment in these properties was greater in Oa compared to Ap. Oxidation followed by crosslinking increased the freeze-thaw stability in Oa and Ap starches at 30, 60, 75, and 90 °C. It also increased the Tg of OCAp and OCOa ≈ 9% compared to the native samples, respectively; while an inverse pattern was observed in apparent viscosity were this value decreased ≈ 0.8 Pa × s for Oa and ≈ 0.5 Pa × s for Ap compared to the double modified samples. All samples presented a thinning cut-type behavior (pseudoplastic), indicating structural differences. Cross-linking in oxidized starches produced a reinforcing matrix that was determined in the paste formation profile. Dual modification (oxidation-cross-linking) could be an alternative for using starches from underused botanical sources, such as apples and oats, with different functional properties and feasible applications in food systems

Elaboration and Characterization of Active Apple Starch Films Incorporated with Ellagic Acid

Apple starch films were obtained from apples harvested at 60, 70, 80 and 90 days after full bloom (DAFB). Mechanical properties and water vapor permeability (WVP) were evaluated. The apple starch films at 70 DAFB presented higher values in the variables of tensile strength (8.12 MPa), elastic modulus (3.10 MPa) and lower values of water vapor permeability (6.77 × 10−11 g m−1 s−1 Pa−1) than apple starch films from apples harvested at 60, 80 and 90 DAFB. Therefore, these films were chosen to continue the study incorporating ellagic acid (EA). The EA was added at three concentrations [0.02% (FILM-EA0.02%), 0.05% (FILM-EA0.05%) and 0.1% (FILM-EA0.1%) w/w] and compared with the apple starch films without EA (FILM-Control). The films were characterized by their physicochemical, optical, morphological and mechanical properties. Their thermal stability and antioxidant capacity were also evaluated. The FILM-Control and FILM-EA0.02% showed a uniform surface, while FILM-EA0.05% and FILM-EA0.1% showed a rough surface and insoluble EA particles. Compared to FILM-Control, EA modified the values of tensile strength, elasticity modulus and elongation at break. The antioxidant capacity increased as EA concentration did. EA incorporation allowed obtaining films with higher antioxidant capacity, capable of blocking UV light with better mechanical properties than film without EA