naa a22 4500 51072406X CHVBK 20180411082928.0 cr unu---uuuuu 180411e20130101xx s 000 0 eng 10.1007/s11947-011-0684-6 doi (NATIONALLICENCE)springer-10.1007/s11947-011-0684-6 Hydrolytic Stability of l -(+)-Ascorbic Acid in Low Methoxyl Pectin Films with Potential Antioxidant Activity at Food Interfaces [Elektronische Daten] [María De'Nobili, Carolina Pérez, Diego Navarro, Carlos Stortz, Ana Rojas] l-(+)-Ascorbic acid (AA) was compartmentalized into a low methoxyl pectin (LMP) film in view of localized antioxidant activity at food interfaces. The AA hydrolysis was specifically studied in the present work in order to determine the ability of the formulated LMP film to stabilize AA. Hence, films were stored at controlled relative humidity (RH) in the absence of air. A commercial LMP characterized by a 40% degree of methylesterification (DM) was used. Since sucrose is normally added for its standardization, films were also made with the dialyzed LMP in order to determine the sucrose effect. Glycerol was used for plasticization. Kinetics of AA loss and subsequent browning development were determined, which are dependent on the RH. Considerable AA retention (t 1/2 = 744, 727, and 185days) was achieved at 33.3%, 57.7%, or 75.2% RH, respectively, at 25°C. Browning rate constants decreased in one order of magnitude with respect to kinetic constants determined from films previously developed with high methoxyl pectin (HMP; DM of 73%). Absence of sucrose in the LMP network only affected the browning kinetics at 75.2% RH. The glass transition temperature (T g) decreased with the increment of moisture content of the films and in a similar degree (T g ≈ −90°C) to that observed for the HMP films, indicating the contribution of water to the network plasticization. However, water was more confined in the LMP network as inferred from the water availability determined by the 1H-NMR and DSC. This was attributed to the water interaction at the Ca2+ junction zones. Sucrose seemed to hinder the retention of water molecules by the polymeric network at 75.2% RH. Springer Science+Business Media, LLC, 2011 Edible film nationallicence Ascorbic acid nationallicence Pectins nationallicence Browning nationallicence Sucrose nationallicence Water nationallicence De'Nobili María Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut Pérez Carolina Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut Navarro Diego Departmento de Química Orgánica-CIHIDECAR, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut Stortz Carlos Departmento de Química Orgánica-CIHIDECAR, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut Rojas Ana Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut Food and Bioprocess Technology Springer-Verlag 6/1(2013-01-01), 186-197 1935-5130 6:1<186 2013 6 11947 https://doi.org/10.1007/s11947-011-0684-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11947-011-0684-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- De'Nobili María Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Pérez Carolina Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Navarro Diego Departmento de Química Orgánica-CIHIDECAR, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Stortz Carlos Departmento de Química Orgánica-CIHIDECAR, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Rojas Ana Departamento de Industrias, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires (UBA), Ciudad Universitaria, 1428, Buenos Aires, Argentina aut NATIONALLICENCE 773 0- Food and Bioprocess Technology Springer-Verlag 6/1(2013-01-01), 186-197 1935-5130 6:1<186 2013 6 11947 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer