BRUNA SAPORITO TEIXEIRA
2 resultados
Resultados de Busca
Agora exibindo 1 - 2 de 2
Artigo IPEN-doc 24329 Comparison of gamma radiation effects on natural corn and potato starches and modified cassava starch2018 - TEIXEIRA, BRUNA S.; GARCIA, RAFAEL H.L.; TAKINAMI, PATRICIA Y.I.; DEL MASTRO, NELIDA L.The objective of this work was to evaluate the effect of irradiation treatment on physicochemical properties of three natural polymers, i.e. native potato and corn starches and a typical Brazilian product, cassava starch modified through fermentation-sour cassava- and also to prepare composite hydrocolloid films based on them. Starches were irradiated in a Co-60 irradiation chamber in doses up to 15 kGy, dose rate about 1 kGy/h. Differences were found in granule size distribution upon irradiation, mainly for corn and cassava starch but radiation did not cause significant changes in granule morphology. The viscosity of the potato, corn and cassava starches hydrogels decreased as a function of absorbed dose. Comparing non-irradiated and irradiated starches, changes in the Fourier transform infrared (FTIR) spectra in the 2000-1500 cm(-1) region for potato and corn starches were observed but not for the cassava starch. Maximum rupture force of the starch-based films was affected differently for each starch type; color analysis showed that doses of 15 kGy promoted a slight rise in the parameter b* (yellow color) while the parameter L* (lightness) was not significantly affected; X-ray diffraction patterns remained almost unchanged by irradiation.Artigo IPEN-doc 24117 The effect of gamma radiation on chia (Salvia hispanica L.) edible film2017 - CHIERENTIN, GABRIEL S.; TEIXEIRA, BRUNA S.; MASTRO, NELIDA L. DELEdible films and coatings have received considerable attention in recent years for their advantages over synthetic films for edible packaging materials. Chia seeds (Salvia hispanica L.) have functional and important nutritional values: protein content (15–25%), fats (30–33%), carbohydrates (26–41%), dietary fiber (18–30%), and ash (4-5%). It also contains a high amount of vitamins, minerals, and antioxidants. Mucilage of chia, a natural exudates from chia seeds, is mainly composed of xylose, glucose and glucuronic acid forming a branched polysaccharide. In the present preliminary work whole chia seeds were irradiated in a 60Co source Gammacell 220 (AECL) with doses of 0, 5 and 10 kGy, dose rate about 0.8 kGy h-1. The irradiated seeds were crushed and soaked in an aqueous solution (6% w/w) together with glycerol (1% w/w), under magnetic stirring for 15 minutes at room temperature and poured into casting plates. The plates were placed in an oven with forced air circulation at 35 °C for at least 20 h. Water uptake, moisture, solubility and water activity of the films were established. The most expressive result was a decrease in water uptake with the increase of the radiation dose. Solubility remained almost unaffected by radiation in doses of 5kGy and moisture analysis showed also a decrease with dose.