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Orientador: Miriam Dupas Hubinger Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: O presente trabalho teve como objetivo o estudo da microencapsulação do óleo de café através de secagem por atomização. Inicialmente, foram avaliadas as variáveis de concentração de sólidos, concentração de óleo em relação aos sólidos e temperatura na secagem por spray dryer, através de um delineamento experimental composto central rotacional completo (23), usando goma arábica como material de parede, sobre as seguintes respostas: umidade, densidade aparente, higroscopicidade, óleo superficial, óleo total, retenção de óleo e eficiência de encapsulação. Nas condições otimizadas do planejamento (30% de sólidos, 15% de óleo em relação aos sólidos e 170º C) foi avaliado o efeito da homogeneização da emulsão a alta pressão (200, 600 e 1000 bar) nas características do pó, comparando-o com o pó obtido a partir de emulsão homogeneizada com o uso de um homogeneizador do tipo rotor-estator. A aplicação de alta pressão reduziu o tamanho das partículas da emulsão, aumentou a eficiência de encapsulação e reduziu o tamanho das partículas do pó, contudo reduziu a retenção de óleo. Ainda, nas mesmas condições selecionadas no planejamento, foram avaliados diferentes materiais de paredes combinados (proteína de soro de leite isolada e maltodextrina; goma arábica e maltodextrina) em diferentes razões (3:1, 1:1 e 1:3) ou puros (goma arábica e proteína de soro de leite). O emprego de materiais de parede diferentes resultou em alterações na viscosidade, no tamanho das gotas das emulsões, na higroscopicidade, densidade e molhabilidade. A mistura de proteína e maltodextrina resultou em alta eficiência de encapsulação e mostrouse como uma possível substituta para a goma arábica. Em seguida, avaliou-se a estabilidade das microcápsulas produzidas com diferentes materiais de parede (goma arábica, maltodextrina e proteína de soro de leite - nas razões 3:1, 1:1, 3:1- e proteína de soro de leite), através da construção de isotermas de sorção e determinação da temperatura de transição vítrea. As microcápsulas produzidas com proteína apresentaram baixa higroscopicidade e alta estabilidade mesmo em ambientes com alta umidade relativa. Foi ainda avaliada a estabilidade oxidativa do óleo de café puro e microencapsulado com diferentes materiais de parede às temperaturas de 25 e 60º C. Tanto o óleo de café puro quanto o microencapsulado apresentaram alta estabilidade oxidativa a 25º C. Já as amostras armazenadas a 60º C apresentaram maiores valores de índice de peróxidos, contudo observou-se uma melhora, ainda que pequena, na estabilidade oxidativa do óleo de café microencapsulado em relação à do óleo puro Abstract: The objective of this work was studying coffee oil microencapsulation by means of spray drying. Initially, the solid concentration, oil concentration in relation to solids and drying temperature were evaluated by using a complete central rotational experimental design (23), using arabic gum as wall material, on the following responses: moisture content, bulk density, hygroscopicity, superficial oil, total oil, oil retention and encapsulation efficiency. Using the planning optimized conditions (30% of solids, 15% of oil in relation to solids, and 170º C) the effect of high-pressure homogenization (200, 600 and 1000 bar) on the powder characteristics was evaluated in comparison with the powder obtained from a homogenized emulsion with the use of a rotor-stator homogenizer. The use of high-pressure reduced the size of emulsion particles, increased encapsulation efficiency and reduced powder particle size; however, it also reduced oil retention. Applying the same conditions selected in the planning, different combined wall materials were evaluated (isolated whey protein and maltodextrin; arabic gum and maltodextrin) in different ratios (3:1, 1:1 and 1:3) or pure (arabic gum and isolated whey protein). The use of different wall materials resulted in changes on viscosity, emulsion particle size and powder's properties, such as hygroscopicity, density and wettability. The combination of protein and maltodextrin resulted in higher encapsulation efficiency and proved itself as a possible substitute for arabic gum. Further, the stability of microcapsules made of different wall materials (arabic gum, maltodextrin and whey protein - in rates 3:1, 1:1 and 1:3- and sole whey protein) was evaluated, by the construction of sorption isotherms and glass transition temperature determination. The microcapsules made of protein presented low hygroscopicity and stability, even in high relative humidity environments. Finally, the oxidative stability of pure and microencapsulated coffee oil with different wall materials was analyzed at 25 and 60º C. Both pure coffee oil and the microencapsulated one presented high oxidative stability at 25º C. The samples stored at 60º C presented high peroxide index values, even though a minor improvement in the oxidative stability was noticed for the microencapsulated coffee oil in comparison with the pure one Mestrado Mestre em Engenharia de Alimentos

The aim of this study was to improve the stability and antioxidant activity of yarrow phenolic compounds upon an in vitro simulated gastrointestinal digestion. Therefore, two types of caseins-based delivery systems, sodium caseinate stabilized nanoemulsions (NEs) and glucono delta-lactone acidified milk gels (MGs), were formulated containing an ultrasound-assisted yarrow extract (YE) at two concentrations (1 and 2.5 mg/mL). Formulations with 1 mg/mL of YE were chosen based on their higher encapsulation efficiency to perform the in vitro digestion experiments. After digestion, YE-loaded NEs only partially protected phenolic compounds from degradation; meanwhile the phenolic composition of YE including in MGs after digestion was quite similar to undigested YE. Moreover, the antioxidant activity of MGs after digestion was higher than NEs digested samples, which confirms the higher protection of YE phenolic compound by the milk gels systems. This research demonstrated the potential use of acidified MGs as carriers to improve the stability and antioxidant activity of yarrow phenolic compounds. Therefore, these matrices could be employed to develop new dairy products enriched with phenolic compounds., This work was supported by Spanish Government (FORCHRONIC Project: ALG-2016-76736-C3-1-R), by Comunidad Autónoma de Madrid (ALIBIRD project: P2018/BAA-4343) and by the Natural Sciences and Engineering Council of Canada, through the Canada Research Chair programme.

Made available in DSpace on 2021-06-25T10:14:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 This study investigates the influence of the atomization parameters on complex coacervation by atomization, and is following a preceding study that presented the technique and investigated the effects of formulation. Complex coacervated capsules were produced by atomization, using emulsions with 1 and 6%(w/w) of gelatin and ginger oil atomized over a 1%(w/w) solution of gum Arabic, at constant polymer ratio of 1:2 (gelatin:gum Arabic) at pH 3.5. The air velocity at the nozzle varied from 72 to 168 m/s and the emulsion velocity at the nozzle varied from 0.4 to 0.6 m/s, maintaining the air to liquid velocity ratio at 170, 220 and 270. The mean diameter of the microcapsules produced varied from 52 to 75 μm and no crosslinking agents were used. The influence of atomization numbers Weber (We) and Ohnesorge (Oh), shear rate and shear stress on the encapsulation performance was carried out and a proposed model was able to predict the final size of the microcapsules produced at We ≥ 180 and Oh = 0.063. Encapsulation efficiency varied from 9 to 95%, and encapsulation yield varied from 50 to 99%. Finally, optimum conditions based on size prediction and microencapsulation parameters were proposed. São Paulo State University (UNESP) Department of Food Engineering and Technology São Paulo State University (UNESP) Department of Food Engineering and Technology

Nowadays, the rational design of particles is an important issue in the development of pharmaceutical medicaments. Advances in manufacturing methods are required to design new pharmaceutical particles with target properties in terms of particle size, particle size distribution, structure and functional activity. Membrane emulsification is emerging as a promising tool for the production of emulsions and solidified particles with tailored properties in many fields. In this review, the current use of membrane emulsification in the production of pharmaceutical particles is highlighted. Membrane emulsification devices designed for small-scale testing as well as membrane-based methods suitable for large-scale production are discussed. A special emphasis is put on the important factors that contribute to the encapsulation efficiency and drug loading. The most recent studies about the utilization of the membrane emulsification for preparing particles as drug delivery systems for anticancer, proteins/peptide, lipophilic and hydrophilic bioactive drugs are reviewed.

Poly(lactide-co-glycolide) (PLGA) microspheres are efficient delivery systems for controlled release of low molecular weight drugs as well as therapeutic macromolecules. The most common microencapsulation methods are based on emulsification procedures, in which emulsified droplets of polymer and drug solidify into microspheres when the solvent is extracted from the polymeric phase. Although high encapsulation efficiencies have been reported for hydrophobic small molecules, encapsulation of hydrophilic and/or amphiphilic small molecules is challenging due to the partitioning of drug from the polymeric phase into the external phase before solidification of the particles. This review addresses formulation-related aspects for efficient encapsulation of small hydrophilic/amphiphilic molecules into PLGA microspheres using conventional emulsification methods (e.g., oil/water, water/oil/water, solid/oil/water, water/oil/oil) and highlights novel emulsification technologies such as microfluidics, membrane emulsification and other techniques including spray drying and inkjet printing. Collectively, these novel microencapsulation technologies afford production of this type of drug loaded microspheres in a robust and well controlled manner.

A novel method is described for the preparation of sterile submicron unilamellar liposomes. The method is based on the lyophilization of double emulsions containing disaccharides as lyoprotectants in both the inner and outer aqueous phase. Using various phospholipids or mixtures of lipids as emulsifiers, the double emulsions can be prepared by a two-step emulsification, including hydrophilic agents in the inner aqueous phase or lipophilic agents in the oil phase. Then, the double emulsions are lyophilized after sterilization by passing them through a 0.22-μm pore filter. Rehydration of the lyophilized products results in liposomes with a relatively high encapsulation efficiency (for calcein, 87%; 5-fluorouracil, 19%; flurbiprofen, 93%) and a size below 200 nm measured by the dynamic light scattering technique (DLS) and the atomic force microscopy (AFM). The liposomes were found to be unilamellar from freeze-fracture electron micrographs and X-ray diffraction patterns. In addition, the liposomes can be reconstituted just before use by rehydration of the lyophilized products which are relatively stable. Thus, this reproducible and simple technique can be used to prepare sterilized, submicron unilamellar liposomes with a relatively high encapsulation efficiency, and excellent stability during long-term storage.

Orientadores: Rosiane Lopes da Cunha, Fabiana Perrechil Bonsanto Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: Os polifenóis possuem alta capacidade antioxidante, sendo o seu uso associado à prevenção e a redução de doenças, estabilização de alimentos e antienvelhecimento. No entanto, estes compostos são instáveis na presença de luz, calor e em determinadas condições de pH, apresentam sabor amargo e adstringente, baixa biodisponibilidade e solubilidade em água, o que pode limitar sua utilização em alimentos. Neste contexto, este trabalho teve como objetivo estudar a encapsulação do ácido gálico (AG) pelo método de emulsificação. As emulsões foram formuladas utilizando-se óleo de soja como fase oleosa, monolaurato de polioxietileno de sorbitana (Tween 20) e polirricinoleato de poliglicerol (PGPR) como surfactantes e ácido gálico como bioativo de interesse. Foram estudadas emulsões do tipo óleo em água (O/A) e água em óleo (A/O) com razão de fases de 25:75 (móleo+Tween20:msoluçãodeácidogálico) e 75:25 (msoluçãodeácidogálico:móleo+PGPR), respectivamente. A concentração de surfactante (1, 2 e 4% m/m) e ácido gálico (0 ou 0,5% m/m) foi variado, de forma a identificar o sistema mais estável e que conferisse maior proteção ao ativo. O AG foi solúvel em água a 25 ºC nas concentrações de 0,1 - 1,3% (m/m). O aumento da concentração de AG (0 - 1,3% m/m) não exerceu efeito na tensão interfacial inicial (22 mN/m) e de equilíbrio (13 - 14 mN/m) dos sistemas óleo de soja/solução de AG, porém na presença dos surfactantes Tween 20 ou PGPR esta propriedade diminuiu para valores menores que 10 mN/m. As emulsões A/O apresentaram distribuição de tamanho de gota bimodal, comportamento pseudoplástico e a presença de AG resultou em menor separação de fases e diâmetro médio da fase dispersa na emulsão. As emulsões O/A apresentaram estabilidade cinética, distribuição monomodal e comportamento de fluido Newtoniano, sendo que a presença de AG também reduziu o diâmetro médio das gotas nas emulsões. O processo de emulsificação se apresentou como um método eficiente de encapsulação, protegendo o ativo da oxidação. A emulsão O/A apresentou maior teor de fenólicos totais e capacidade antioxidante quando comparada à emulsão A/O. Porém, ambas as emulsões apresentaram altas eficiências de encapsulação do bioativo (? 86,75%), podendo ser utilizadas como ingredientes em processos para fabricação de produtos de diversas naturezas, devido às diferentes propriedades físicas das emulsões O/A e A/O Abstract: Polyphenols have high antioxidant capacity, and its use is associated with the prevention and reduction of diseases, stabilization of food and anti-aging. However, these compounds are unstable in presence of light, heat and some pH conditions, exhibit bitter and astringent taste, low bioavailability and solubility in water, which could limit its use in food systems. In this context, this work is aimed to study the encapsulation of gallic acid (GA) by emulsification method. Emulsions were formulated using soybean oil as oil phase, polyoxyethylene sorbitan (Tween 20) and polyglycerol polyricinoleate (PGPR) as surfactants and gallic acid as bioactive. The systems evaluated were oil-in-water (O/W) and water-in-oil (W/O) emulsions with 25:75 (woil+Tween20:wgallicacidsolution) and 75:25 (wgallicacidsolution:woil+PGPR) ratio, respectively. The surfactant concentration (1, 2 and gallicacidsolution oil+ PGPR 4% w/w) and gallic acid (0 or 0.5% w/w), was evaluated in order to identify the more stable system and greater protection to the bioactive. GA was soluble in water at 25 °C for concentration ranging from 0.1 up to 1.3% (w/w). The GA concentration increase (0 - 1.3% w/w) had no effect on the initial interfacial tension (22 mN/m) and equilibrium (13- 14 mN/m) in GA solution/soybean oil systems, however, in presence of Tween 20 or PGPR this property decreased to less than 10 mN/m. The W/O emulsions showed bimodal droplet size distribution, pseudoplastic behavior and the presence of GA decreased the phase separation and the average diameter of the emulsion dispersed phase. The O/W emulsions exhibited kinetic stability, monomodal droplet size distribution, Newtonian fluid behavior, and the presence of AG also reduced the average diameter of the droplets in emulsions. Results showed that the emulsification process was an efficient encapsulation method, protecting the bioactive against oxidation. The O/W emulsion showed content higher of totals phenolic and antioxidant capacity in comparison to the W/O emulsion. However, both emulsions exhibited high efficiencies of encapsulation of bioactive (? 86.75%) and can be used as ingredients in different products, due to the different physical properties of the O/W and W/O emulsions Mestrado Engenharia de Alimentos Mestra em Engenharia de Alimentos CNPQ CAPES FAPESP

Orientador: Miriam Dupas Hubinger Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: O presente trabalho teve como objetivo o estudo da microencapsulação do óleo essencial de laranja através do processo de secagem por atomização. Inicialmente foram realizados alguns testes para fixar a temperatura do ar de secagem e a vazão mássica da alimentação, com base na maior retenção de óleo, fixando-se o teor de sólidos em 30% e o teor de óleo em relação aos sólidos em 20%. A partir das condições selecionadas nessa primeira etapa (temperatura do ar de secagem de 190°C e vazão mássica de 0,8 L/h), foram avaliadas as variáveis concentração de sólidos, concentração de óleo em relação aos sólidos e pressão de homogeneização da emulsão, através de um delineamento experimental composto central rotacional 23, usando misturas de concentrado protéico do soro de leite com maltodextrina, em uma proporção 1:3 como material de parede, sobre as seguintes respostas: tamanho médio das gotas da emulsão, viscosidade, higroscopicidade, umidade, atividade de água, densidade aparente, óleo retido na emulsão e no pó, óleo superficial, eficiência de encapsulação e retenção de óleo. Nas condições selecionadas do planejamento nesta segunda etapa (30% de sólidos totais, 15% de óleo em relação aos sólidos e 650 bar) foi avaliado o efeito do número de passagens (1, 2, 3 e 4 passagens) da emulsão pelo homogeneizador a alta pressão sobre as características do pó. O aumento do número de passagens pelo homogeneizador reduziu o tamanho das gotas da emulsão até a segunda passagem, acima da qual houve excesso de processamento da emulsão e as gotas coalesceram resultando em tamanhos maiores. Embora com o aumento do número de passagens da emulsão, através do homogeneizador, o teor de óleo superficial tenha diminuiudo, também diminuíram o óleo retido na emulsão, a eficiência de encapsulação e a retenção de óleo. Nas mesmas condições selecionadas no planejamento, foram avaliadas diferentes misturas de materiais de parede (concentrado protéico de soro de leite: maltodextrina DE 20 e goma arábica: maltodextrina DE 20) em diferentes razões (3:1, 1:1 e 1:3) ou puros (concentrado protéico de soro de leite e goma arábica). O emprego de diferentes materiais de parede resultou em alterações na viscosidade, tamanho da gota da emulsão, higroscopicidade, densidade, microestrutura das partículas, eficiência de encapsulação e retenção de óleo. Na etapa seguinte do trabalho, avaliou-se a estabilidade das microcápsulas produzidas com diferentes materiais de parede sobre a retenção do d-limoneno e a estabilidade oxidativa das partículas quando armazenadas a 40°C, durante cinco semanas, em uma umidade relativa de 32%. O nível de oxidação foi avaliado com base no teor de limoneno-1,2-epóxido e carvona. Finalmente foi calculado o tempo de vida média das partículas com base no teor de limoneno encapsulado. As microcápsulas de óleo de laranja com matrizes constituídas por altos teores de concentrado protéico do soro de leite apresentaram a maior estabilidade oxidativa, durante o armazenamento a 40°C Abstract: This work aimed to study the microencapsulation of orange essential oil by spray drying. Initially some tests were performed to determine the air drying temperature and feed flow rate based on higher oil retention, settling the solids as 30% and the relation oil-solids as 20%. From the conditions selected in the first stage (drying temperature of 190 ° C and mass flow of 0.8 L/h) solids concentration, oil concentration in relation to solids and homogenization pressure of the emulsion were evaluated, through a central composite experimental design 23, using mixtures of whey protein concentrated with maltodextrin at a ratio 1:3, as wall material, on the following responses: average size of droplets of the emulsion, viscosity, hygroscopicity, moisture, water activity, bulk density, withholding oil emulsion, oil trapped in the dust compared to the emulsion, oil surface, encapsulation efficiency and oil retention. Under the conditions selected in the second stage of the experimental design (30% total solids, 15% oil in relation to solids and 650 bar) it was evaluated the effect of the number of passages (1, 2, 3 and 4 passes) of the emulsion by high pressure homogenizer on the characteristicas of the powder. The increase in the number of passes dropped by homogenizer reduced the emulsion droplet size until the second passage, above which there was an over-processing and emulsion droplets coalesced, resulting in larger sizes. Although the increase in the number of emulsion passes through the homogenizer the surface oil content decreased also decreased the oil retained in the emulsion, the encapsulation efficiency and oil retention. Under the same conditions described in the planning different mixtures of wall materials (whey concentrate, maltodextrin DE 20 and gum arabic: maltodextrin DE 20) at different ratios (3:1, 1:1 and 1:3) or pure state (whey protein concentrate milk and gum arabic) were evaluated. The use of different wall materials resulted in changes in viscosity, emulsion droplet size, hygroscopicity, density, microstructure of the particles, encapsulation efficiency and oil retention. In the next stage of the study it was evaluated the stability of the microcapsules produced with different wall materials on the retention of d-limonene and oxidative stability of the particles when stored at 40 °C for five weeks in a relative humidity of 32%. The level of oxidation was evaluated based on the content of limonene-1,2-epoxide and carvone. Finally, it was calculated the average shelf life of particles based on the content of limonene encapsulated. The microcapsules of orange oil with matrices consisting of high levels of protein concentrate of whey showed the highest oxidative stability during storage at 40 °C, showing the lowest levels of formation of carvone and limonene-1,2-epoxide Mestrado Engenharia de Alimentos Mestre em Engenharia de Alimentos