Effect of processing on physico-chemical characteristics of dietary fibre concentrates obtained from peach (Prunus persica L.) peel and pulp

In order to obtain rich dietary fibre concentrateswith enhanced functional properties frompeach peel and pulp,a treatment with ethanol (96% v/v) was performed previous to drying under 30 °C forced air convection for 7 h or under freeze drying. All the dietary fibre concentrates isolatedwere enriched in cell wall polymers and a high polyphenol content was associated to them. The yield of those proceeding from peel almost doubled the one of concentrates obtained from pulp and high hydration capacities were shown by all the concentrates. Fractions from peel showed the darkest colour. Oil holding capacity (1.81–2.4 g/g) was higher than the one reported in bibliography for peach bagasse (1.02 g/g) and quince wastes (1.59 g/g). Concerning the effect of the drying technique used, it was observed that air drying gave origin to pulp dietary fibre concentrates of lower oil holding capacity and less solid behaviour than freeze drying.Fil: de Escalada Pla, Marina Francisca. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: González, Patricia. Universidad Tecnológica Nacional. Facultad Regional Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; ArgentinaFil: Sette, Paula Andrea. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Portillo, Florencia Soledad. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; ArgentinaFil: Rojas, Ana Maria Luisa. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gerschenson, Lia Noemi. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Evaluation of the rate of abiotic and biotic degradation of oxodegradable polyethylene

The recent introduction of oxo-degradable additive in the Argentinean market has motivated the study of the effect of abiotic (temperature and ultraviolet (UV) radiation) and biotic (aerobic in compost) degradation on the structure and mechanical behavior of films of polyethylene (PE) and oxo-degradablepolyethylene (PE+AD).Physico-chemical tests show that the failure strain and the carbonyl index of degraded PE and PE+AD samples depend on the UV irradiation dose. Furthermore, the additive plays a crucial role in the degradation and subsequent decay of the molecular weight.It was observed that, for the same dose, the most deteriorated material was the one exposed to the lowest irradiance, emphasizing the importance of the time of exposure to UV radiation. The ratio between the irradiance and the critical dose, is a characteristic time associated to the sharp decay on the failure strain. The critical dose decreases significantly when increasing the temperature of the photodegradation assay.PE is more susceptible to thermal degradation than PE+AD; the latter only degrades under thermal aging at the highest temperature.Initially biotic degradation in compost showed an increasing production of carbon dioxide for both previously UV-degraded and untreated PE+AD. It is also remarkable that UV-degraded samples of PE and PE+AD with differences in their abiotic degradation level, reached the same final biotic degradation level. It was observed that although the additive increased the abiotic photodegradation, the molecular weight reduction in compost was not enough to reach the maximum biotic degradation level established by international standards for biodegradable materials.Fil: Portillo, Florencia Soledad. Universidad Nacional de San Martín. Instituto Sabato; ArgentinaFil: Yashchuk, Oxana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín; ArgentinaFil: Hermida, Elida Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Instituto Sabato; Argentin