BRUNA SAPORITO TEIXEIRA

BRUNA SAPORITO TEIXEIRA

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Effects of electron beam irradiation on ozone-modified potato starch film
2023 - TEIXEIRA, BRUNA S.; MASTRO, NELIDA L. del
Functional starch-based films are promising materials being developed at different laboratories. Native and modified starches are two materials being employed for this purpose. Chemical modification of starch generally involves esterification, etherification, or oxidation of the units that make up the starch polymers. Ozone constitutes an advanced oxidation technology for starch modification. In this work, properties of two kinds of materials - ozone-modified potato starch and irradiated ozone-modified potato starch-based films - were evaluated. Potato starch films were submitted to electron beam irradiation with doses up to 40 kGy. Films were produced by the casting technique using native and ozonated potato starch, glycerol as the plasticizer, and water as the solvent, and characterized in term of solubility and absorption of water, determination of oxygen gas transmission rate and Fourier Transform infrared Spectroscopy (FTIR) analysis. Ozone-modified potato starch presented strong alterations on pasting properties, with drastic reduction of viscosity values, water solubility and oxygen permeability. The data reported in this work contribute to the understanding of the ozone-modification process on starch and suggests further possibilities of industrial applications of ozonation on biomaterials.
Incorporação e nanoencapsulação de agentes antioxidantes em filmes de amido e ação da irradiação por feixes de elétrons
2022 - TEIXEIRA, BRUNA S.
O desenvolvimento de filmes biodegradáveis é uma alternativa ao uso de embalagens n o amigáveis ao meio ambiente. Para produção desses filmes, diversos polímeros naturais podem ser utilizados, dentre eles, o amido, no qual apresenta boas características, propriedades e facilidade para sua obtenção. A adi o de antioxidantes naturais livres ou encapsulados pode contribuir ainda mais no desenvolvimento de filmes funcionais com atividade antioxidante. O objetivo deste trabalho foi desenvolver filmes ativos, à base de polímeros naturais de fonte renovável, o amido, pela técnica casting e extrusão, adicionados com compostos bioativos de hibisco e cúrcuma livres e nanoencapsulados e ação da irradiação por feixes de elétrons. Procedeu-se a extração por micro-ondas e ultrassom dos compostos bioativos do hibisco e da cúrcuma com diferentes solventes e temperaturas, assim como a caracterização em relação à atividade antioxidante, determinação dos compostos fenólicos, atividade anti-inflamatória e antimicrobiana. Foi realizado a encapsulação desses compostos através da secagem por vaporização (nanospray dryer) e caracterizados quanto às propriedades físicas, fisico-químicas, morfológicas, bioativas, parâmetros colorimétricos, diâmetro e tamanho das partículas. As partículas mais estáveis dos extratos foram incorporadas nos filmes preparados por extrusão. As soluções filmogênicas para a técnica casting foram preparadas nas concentrações de 5% (p/v) de amido de batata, 3% de glicerol, 0.5% de propionato de cálcio (C6H10CaO4) sob agitação constante até gelatinização do amido. Os filmes com os compostos bioativos foram preparados com solução de 1 e 2% de hibisco e cúrcuma, com as mesmas proporções de plastificante glicerol e conservante (propionato de cálcio). Análise do perfil de viscosidade desses hidrogéis foi realizado. Os filmes processados por extrusão foram preparados com as partículas encapsuladas com os compostos bioativos. Foram elaboradas 5 formulações: filme de amido, filme de amido com nanoapartículas de hibisco a 1 e 2% e filme de amido com nanopartícula de cúrcuma a 1 e 2%. Após o preparo os filmes foram irradiados com feixes de elétrons com doses de 5, 10, 20 e 40 kGy. A irradiação ionizante foi utilizada com o intuito de verificar a influência nas propriedades bioplásticas dos filmes à base de amido, assim como as propriedades mecânicas e de barreira. Estes bioplásticos foram caracterizados quanto às propriedades físicas, fisico-químicas, morfológicas, biotivas, mecânicas, de barreira e térmicas. As propriedades dos filmes estudados foram afetadas dependendo da proporção de antioxidante adicionado.
Impact of electron beam irradiation in potato starch films containing hibiscus aqueous extract
2021 - TEIXEIRA, B.S.; CHIERENTIN, G.S.; DEL MASTRO, N.L.
The development of starch films containing natural antioxidants is one alternative of active packaging. Starch is a well studied natural biopolymer that can be used for the development of biodegradable films because it presents a low cost, is easy to obtain and presents good ability to form films. Hibiscus sabdariffa, commonly known as roselle or red sorrel, is an annual her baceous sub shrub that contains many types of biocompounds, including organic and phenolic acids. The aim of the present work was to determine the influence of electron beam irradiation on potato starch film containing hibiscus extract. The aqueous hibiscu s solution was prepared by boiling for 3 min 1% w/ml dehydrated hibiscus flowers in 500 ml deionized water. The film forming solution was prepared by casting ( potato starch, 3% glycerol as plasticizer and the hibiscus solution) and irradiated in a 1.5 M eV electron beam accelerator Dynamitron II (Radiation Dynamics Inc.), with doses of 0, 20, 40 and 60 kGy. After drying some mechanical properties were measured. The tensile strength of the control films and the irradiated ones was established. There were n o significant differences among them. Hibiscus antioxidants were able to prevent the starch radiation degradation process caused by radiation induced free radicals.
Total phenolic compounds of irradiated chia seeds
2021 - CHIERENTIN, G.S.; TEIXEIRA, B.S.; MASTRO, N.L.
Chia seeds (Salvia hispanica L.) is a good source of oil, protein, dietary fiber, minerals and polyphenolic compounds. In order to study the influence of the processing methods on the content of phenolic compounds, the objective of this work was to evaluate the effect of gamma radiation, doses 0 (control), 5, 10 and 20 kGy, on the total phenolic compounds extracted from chia seeds. Seeds were first defatted and extracts produced with proper solvents. Total phenolic content was determined according to Folin-Ciocalteu’s method and the extraction solvents applied were ethanol 100%, ethanol 70%, ethanol 50%, methanol 100%, methanol 70% and methanol 50%. When using ethanol 100%, ethanol 70 %, ethanol 50%, methanol 100% and methanol 70%, the extraction yield was independent of the absorbed dose. With methanol 50%, the irradiation process affected positively the total phenolic yield from of chia seeds. In general, the absorbed dose as well as the nature of the solvent affected the extraction yield, although in a limited manner.
Radiation, Plant Proteins and Sustainability
2020 - TAKINAMI, PATRICIA Y.I.; UEHARA, VANESSA B.; TEIXEIRA, BRUNA S.; MASTRO, NELIDA L. del
Impact of electron beam irradiation in potato starch films containing hibiscus aqueous extract
2019 - TEIXEIRA, BRUNA S.; CHIERENTIN, GABRIEL S.; DEL MASTRO, NELIDA L.
The development of starch films containing natural antioxidants is one alternative of active packaging. Starch is a well studied natural biopolymer that can be used for the development of biodegradable films because it presents a low cost, is easy to obtain and presents good ability to form films. Hibiscus sabdariffa, commonly known as roselle or red sorrel, is an annual herbaceous sub shrub that contains many types of biocompounds, including organic and phenolic acids. The aim of the present work was to determine the influence of electron beam irradiation on potato starch film containing hibiscus extract. The aqueous hibiscus solution was prepared by boiling for 3 min 1% w/ml dehydrated hibiscus flowers in 500 ml deionized water. The film forming solution was prepared by casting (5% potato starch, 3% glycerol as plasticizer and the hibiscus solution) and irradiated in a 1.5 MeV electron beam accelerator Dynamitron II (Radiation Dynamics Inc.), with doses of 0, 20, 40 and 60 kGy. After drying some mechanical properties were measured. The tensile strength of the control films and the irradiated ones was established. There were no significant differences among them. Hibiscus antioxidants were able to prevent the starch radiation degradation process caused by radiation induced free radicals.
Total phenolic compounds of irradiated chia seeds
2019 - CHIERENTIN, GABRIEL S.; TEIXEIRA, BRUNA S.; DEL MASTRO, NELIDA L.
Chia seeds (Salvia hispanica L.) is a good source of oil, protein, dietary fiber, minerals and polyphenolic compounds. In order to study the influence of the processing methods on the content of phenolic compounds, the objective of this work was to evaluate the effect of gamma radiation, doses 0-20 kGy, on the total phenolic compounds extracted from chia seeds. Seeds were first defatted and extracts produced with proper solvents. Total phenolic content was determined according to Folin-Ciocalteu’s method and the extraction solvents applied were ethanol 100%, ethanol 70%, ethanol 50%, methanol 100%, methanol 70% and methanol 50%. When using ethanol 100%, ethanol 70 %, ethanol 50%, methanol 100% and methanol 70%, the extraction yield was independent of the absorbed dose. With methanol 50%, the irradiation process affected positively the total phenolic yield from of chia seeds. In general, the absorbed dose as well as the nature of the solvent affected the extraction yield, although in a limited manner.
Comparison of gamma radiation effects on natural corn and potato starches and modified cassava starch
2018 - 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.
The effect of gamma radiation on chia (Salvia hispanica L.) edible film
2017 - CHIERENTIN, GABRIEL S.; TEIXEIRA, BRUNA S.; MASTRO, NELIDA L. DEL
Edible 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.
Radiation, plant proteins and sustainability
2016 - TAKINAMI, PATRICIA Y.I.; UEHARA, VANESSA B.; TEIXEIRA, BRUNA S.; DEL MASTRO, NELIDA L.
The best sources of proteins for human nourishment come from animal origin. But, conventional meat production involves not only animal suffering but, also, prodigious amounts of water use and significant global warming gases produced per pound of meat. Sustainable plant proteins are good for human beings, as well as, for the planet. Specific natural resources like pulses, in particular, represent a very environmentally friendly and sustainable food source and are rich of high-quality and cost-effective protein ingredients. Ionizing radiation may contribute to food safety and food security. Also, irradiation could serve as an additional food processing method for inactivation or removal of certain antinutritional factors. In this work, the benefits of plant protein sources, particularly pulse protein foods, are highlighted. Moreover, a survey on database since 1970, about the relation among pulses, plant protein and ionizing radiation has been presented. Highlights: Pulses represent a very environmentally friendly and sustainable food source. Pulses are rich sources of high quality and cost effective protein ingredients. Ionizing radiation may contribute to food safety and food security and it could be applied for inactivation or removal of certain antinutritional factors.