Chia (salvia hispanica l.): potencial antioxidante, nutricional e funcional

• Autor(a) principal: Alcântara, Maristela Alves
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/tede/9418
• topic: Salvia hispanica L; Propriedades_nutricionais; Propriedades_funcionais ácido α-linolênico; Óleo_microencapsulado; Salvia hispanica L; nutritional_properties; functional_properties; α-linolenic acid; microencapsulated_oil.; CIENCIA E TECNOLOGIA DE ALIMENTOS::TECNOLOGIA DE ALIMENTOS

Functional foods are highlighted for promoving beneficial effects on human health. Among them, chia seed (Salvia hispanica L.) is a natural source of polyunsaturated fatty acids, with high levels of α-linolenic acid, and other important nutritional components, such as vitamins, minerals and antioxidants. Considering the growing interest in the use of chia in human diet and its many benefits reported in the literature, this study determined the physicochemical characteristics and nutritional properties of chia seed grown in southern Brazil. It also investigated the phenolic compounds present in the seed and developed a microcapsule containing chia oil. A review was prepared addressing the main components: lipids, proteins, fibers and phenolic compounds, emphasizing the benefits of the functional properties of chia seed on human health and in the preparation of food products. The characterization of chia seeds grown in Brazil revealed considerable amounts of protein (25,03 g /100 g), lipids (34,41 g /100 g) and fibers (36,50 g/100 g), as well high amounts of essential amino acids and nutritionally important minerals, such as calcium, potassium, zinc and selenium. The fatty acid profile of chia oil revealed a high degree of unsaturation, consisting of oleic, linoleic and, predominantly, α-linolenic acids (65,61 g/100 g). The chia oil showed a high tocopherol content (586,78 mg/g), with γ-tocopherol isomer representing more than 90% of all isomers and phenolic compounds such as myricetin, quercetin, and kampferol synaptic acid. The efficiency of the extraction of phenolic compounds from seeds of chia was determined utilizing the statistical tool of mixture planning, simplex-lattice design. The solvents used were acetone, ethanol and water, and the responses analyzed were total phenolic content (TPC), antioxidant activity by the capture of the free radical DPPH· and ferric reduction ability (FRAP). The polarity of the solvents and their mixture strongly influenced the extraction, in which moderately polar mixtures such as acetone-water and ethanol-water were highly efficient to extract the antioxidant phenolic compounds. The phenolic profile of the extracts showed that synaptic, caffeic, salicylic, protocatequímico, hydroxybenzoic and gentisic acids, as well flavonoids, myricetin, quercetin and kaempferol are the major compounds responsible for high antioxidant activity. The addition of antioxidants naturally present in the seeds of chia and a combination with α-tocopherol and myricetingave oxidative stability to the chia oil when evaluated by the accelerated method. The spray-dry technique was evaluated as a way to protect the chia oil, as well the influence of the use of rotor-stator type homogenizersand ultrasound on the formation of emulsions and on the properties of the microcapsules. Application of the microencapsulation technology presented encapsulated oil results percentage (28,76%) and encapsulation efficiency (96%) similarly to commercial microparticles. Also, it was efficient in preserving the fatty acid profile of the oleaginous matrix and increased the time of the oxidative stability of the oil in natura (0,6 hours) to 8,2 hours of microencapsulated oil, especially when ultrasound was used. Nutritional information reported in this study illustrates the potential benefits that chia seed can promote on human health, and shows the potential use in industrial applications.