ENCAPSULATION EFFICIENCY AND THERMAL STABILITY OF ORANGE ESSENTIAL OIL MICROENCAPSULATED BY SPRAY DRYING AND BY COACERVATION

Orange essential oil was microencapsulated by spray drying using maltodextrin and modified starch as carrier agents, and also by coacervation using sodium alginate. The influence of different microencapsulation methods and carriers on the microscopic and thermal characteristics of the product and on the encapsulation efficiency of the microparticles was investigated. According to a technique based on headspace extraction coupled to gas chromatography, the encapsulation efficiencies were above 99 % for both methods, and the oil was composed mainly of D-limonene (95.7 %) and mircene (1.66 %). Coacervation and spray drying produced microparticles of 908.63 μm and 1.02 μm, respectively, which increased the thermal stability of the oil. Nonetheless, the coacervated microparticles showed higher thermal stability and boiling point than the spray-dried ones

Application of near infrared spectroscopy to predict the average droplet size and water content in biodiesel emulsions

AbstractNIR spectroscopy was used to predict the average droplet size and water content in water/biodiesel emulsions. The emulsions were prepared from industrial biodiesel obtained from soybean oil (85wt%) and animal fat (15wt%) by methylic route. NIR spectra was collected in the transmittance mode with the diffuse reflectance technique. Based on the NIR spectroscopy results, it can be pointed out that this methodology has the sensibility to infer the droplet size and water content in the biodiesel emulsions. Two techniques were used to obtain the multivariate models: the partial least squares (PLS) and artificial neural network (ANN) models. Satisfactory values of mean error for the external validation were obtained, with 9.53% to PLS model for average droplet size and 8.79% for water content, since they are close to the experimental standard deviation. The performance of ANN models demonstrated that this technique allowed the prediction of average droplet size and water content with mean errors of 6.10% and 13.20%, respectively. These errors are close to the analytical error associated to the method used indicating that the NIR spectroscopy is a good alternative to be used for this purpose

Granules morphology and rheological behavior of green banana (Musa cavendishii) and corn (Zea mays) starch gels Morfologia dos grânulos e comportamento reológico dos géis de amido de banana verde (Musa cavendishii) e milho (Zea mays)

In this work, it was used starch obtained from green banana (Musa cavendishii) and commercial corn (Zea mays) starch in order to compare the granule morphology and the rheological behavior of these gel-starches. Images of starch granules morphology were obtained from scanning electron microscope (SEM). The banana starch granules presented an oval and ellipsoidal shape with irregular diameters. Neverthless, the granules of corn starch showed a poliedric shape, with different sizes. The rheological behavior of gel starch solutions showed a non-newtonian character with a pseudoplastic behavior. Herschel-Bulkley model gave a good description on the rheological behavior of the gel starch. Banana gel-starch solutions showed higher values of shear stress and apparent viscosity when compared with corn gel-starch solutions. A progressive decrease in shear stress and viscosity occurred with the addition of sodium chloride and sucrose.<br>No presente trabalho foi utilizado amido obtido de banana verde (Musa cavendishii) e amido de milho (Zea mays) comercial, com o objetivo de comparar a morfologia dos grânulos e o comportamento reológico dos géis. As imagens da morfologia dos grânulos foram obtidas por microscopia eletrônica de varredura. Os grânulos de amido da banana apresentaram forma oval e elipsoidal com diâmetros irregulares, todavia, os grânulos do amido de milho mostraram forma poliédrica e diferentes tamanhos. As análises reológicas dos géis das soluções de amido mostraram caráter não-newtoniano, pseudoplástico. O modelo de Herschel-Bulkley foi o que melhor representou comportamento reológico dos géis. O gel de amido de banana verde obteve maiores valores de tensão de cisalhamento e viscosidade aparente quando comparada ao gel de amido de milho. Ocorreu um decréscimo progressivo na tensão de cisalhamento e na viscosidade com a adição de cloreto de sódio e sacarose aos géis

Avaliação de germoplasma de camomila e densidade de semeadura na produção e composição do óleo essencial Evaluation of germplasm and seeding rate over the production and composition of chamomile essential oil

O cultivo de camomila na região Sul do Brasil tem sido realizado utilizando-se como material genético a cultivar Mandirituba. Apesar da produção de capítulos florais e teor de óleos essenciais apresentado por esta cultivar ser considerado satisfatório, tem sido observada nas regiões produtoras a ocorrência de problemas fitossanitários que resultam em perdas significativas da produção. Este trabalho teve como objetivos comparar materiais genéticos de camomila provenientes da Holanda, Dinamarca e Mandirituba, e avaliar o efeito de diferentes densidades de semeadura no desenvolvimento das plantas, produção de capítulos, rendimento e qualidade do óleo essencial da cultivar Mandirituba, atualmente cultivada na região. Os experimentos foram conduzidos no município de Piraquara (PR). A extração do óleo essencial foi realizada por hidrodestilação em aparelho tipo Clevenger e a determinação da composição do óleo foi feita por cromatografia em fase gasosa acoplada ao espectrômetro de massa (GC/MS). Os materiais genéticos provenientes da Holanda e de Mandirituba apresentaram maior produção de biomassa seca de capítulos, em relação ao material genético da Dinamarca. A cultivar Mandirituba apresentou o maior rendimento de óleo essencial (4,71 mL g-1 ms), sendo também superior em relação à produtividade de óleo essencial (2,40 L ha-1). Os materiais procedentes da Dinamarca e de Mandirituba apresentaram composição do óleo essencial semelhantes. A densidade de plantio de 1,0 kg ha-1 da cultivar Mandirituba resultou em melhor desenvolvimento das plantas e maior produção de óleo essencial. Quantidades superiores a 3,0 kg ha-1 de sementes não resultaram em maior densidade de plantas tendo em vista a alta competição e percentual de plântulas mortas.<br>The cultivar Mandirituba is the only genetic material for chamomile cultivation in southern Brazil. Besides the limitations regarding floral buds and the yield of essential oil presented by this cultivar, phytosanitary problems have also been observed. The objectives of this work were to compare the genetic materials from the Netherlands, Denmark and Mandirituba and to evaluate the effect of seeding rate on floral heads development and essential oil production, yield and quality. The experiments were carried out at field conditions in Piraquara, Paraná state, Brazil. The essential oil extraction was obtained by hydrodistillation using a Clevenger apparatus and the oil composition was analyzed by gas chromatography coupled to mass spectrometry (GC/MS). The genetic materials from the Netherlands and Mandirituba presented statistically higher dry mass accumulation than the ones from Denmark. However the material from Mandirituba showed a great essential oil yield (4.7 mL g-1 ms) and productivity (2.40 L ha-1). The genetic material from Denmark and Mandirituba showed similar essential oil composition. The density of 1.0 kg ha-1 for cultivar Mandirituba resulted on great plant development and essential oil production. The use of 3.0 kg ha-1 of seeds did not increase plant density due to the high plant competition