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An alternative use of shiitake stipes, usually treated as waste, was proposed for the production of a powder ingredient, rich in umami compounds, aiming its application in food. The extraction of umami compounds was optimized through the Response Surface Methodology (RSM), in order to obtain an extract with high umami taste intensity. From the optimized condition, a comparative analysis of shiitake stipes dehydration method was performed. Stipes were dehydrated by hot air drying (HD) and freeze drying (FD), submitted to extraction and the umami compounds in the extracts were compared. The comparative analysis showed that the 5′ - nucleotides are more sensitive to prolonged heating, while the release of free amino acids (FAA) was favored by hot air drying. The HD samples extract showed higher Equivalent Umami Concentration (EUC). The spray drying of the HD samples extract allowed the production of a newly powder ingredient rich in umami compounds (Umami Ingredient) that can be applied in diverse food matrices. Due to the presence of umami compounds, Umami Ingredient can be a potential alternative to help in the process of sodium reduction by enhancing food flavor. CNPq / CAPES

Lipid oxidation is usually responsible for oil downgrading of spray-dried powders and it is strongly dependent on the storage conditions. Direct measurements of the oxygen uptake using cost-effective methods combined with the study of water adsorption of the powders allow evaluating their barrier properties against oxidation. Therefore, a low-cost and simple apparatus based on the Warburg’s manometric technique was built, and its results were compared to Rancimat and Oxipres methods. Firstly, free unsaturated oil (fish oil) was evaluated and data showed a strong positive correlation between the oxygen uptakes for the new apparatus (0.015 mL O2/ h) and Oxipres method (Pearson’s coefficient = 0.97). After, different surface-active compounds (SAC) (whey protein isolate – WPI, gelatin – GE, or modified starch – MS) mixed to maltodextrin (MD) were used to encapsulate the fish oil via spray drying. The lowest oxygen uptake was obtained by MD+ WPI (0.0018 mL O2/h), followed by MD + GE (0.0103 mL O2/h) and MD + MS (0.0291 mL O2/h), with similar behavior obtained by Rancimat method. The lowest protective barrier of MD + MS-powders was confirmed by the comparatively higher susceptibility to water adsorption, and consequently the lower glass transition temperature (∼58.7 °C at water activity = 0.3−0.4). This study presented a successful creation of an apparatus to provide useful, fast and effective information about oxygen consumption by fish oil and encapsulated fish oil, allowing the understanding of the protection of SAC against oxidation in spray-dried emulsions. The proposed apparatus can be easily implemented in laboratories, with potential application for other oxygen-sensitive products. FAPESP

The present work proposes using microencapsulation, ethanol, ultrasound and convective drying to obtain iron fortifed pineapple chips. Iron microparticles were produced by ferrous sulphate encapsulation with maltodextrin by spray drying. As a hydrophilic material, microparticles were dispersed in ethanol to be incorporated into the pineapple tissue, with or without the application of ultrasound. Then, the efect of diferent pre-treatment times with ethanol and ethanol+ultrasound was evaluated on pineapple drying. Finally, the residue of ethanol was evaluated in the fnal products. Pre-treatment with ethanol and ethanol+ultrasound allowed to increase signifcantly the iron content of pineapple chips (up to 1000% in comparison with control). In addition, the drying time decreased from 35.4 to 51.9% with the utilization of ethanol and ultrasound. Pretreatment for 7.5 min allowed to reduce the drying time and to achieve negligible residual ethanol in the sample. The results demonstrated that the combination of the proposed technologies can be used to obtain pineapple chips enriched in iron, with reduced time of drying and a negligible residue of ethanol. Fapesp / CNPq

Microencapsulation is used for protection and release of bioactive compounds. Combination of encapsulation methods allows the production of matrices with better technological properties compared to the application of one of the methods alone. Use of ionic gelation produces porous microparticles, and coating it with a protein, by electrostatic interaction, may contribute to a better protection of the active compound. The objective of the research was to produce alginate microparticles (AG) through ionic gelation and to coat them with soluble protein from soy protein concentrate. Two factors were studied, calcium concentration during ionic gelation (0.8, 1.6 and 2.4% w/w) and pH (3.5 and 7.0) of the protein solution for electrostatic interaction. Zeta potential (ZP) of biopolymers and microparticles were determined. Microparticles were characterized according to its morphology, average size and size distribution, as well as protein adsorption. Microparticles presented (154-334μm) multinuclear distribution of active compound, continuous and smooth surface, with a great standard deviation considering average size. The calcium concentration did not influence the protein adsorption on microparticles.The pH used in protein adsorption showed significant effect, with higher adsorption occurring at pH 3.5 (6.5 to 6.7% w/w, dry basis,db, of adsorbed protein) compared to pH 7.0 (pKa AGpKa AG

Esta pesquisa teve como principal objetivo verificar a capacidade da levedura e seus derivados, autolisado e extrato, em manter o crescimento de ratos recém-desmamados, quando usados em substituição parcial a uma dieta-padrão ideal. Usou-se substituição de 10, 20 ou 30% da dieta-padrão recomendada pelo American Institute of Nutrition -- 93G, por uma mistura (amido de milho + produto de levedura + óleo de soja), mantendo as dietas modificadas isoprotéicas (20% proteína) e isocalóricas. Com as substituições, os produtos de levedura participaram das dietas nas concentrações de 4, 8 ou 12%, respectivamente. As dietas substituídas, contendo diferentes proporções de produtos de levedura, provocaram crescimento dos ratos igual ou superior ao da dieta-padrão. O ritmo de crescimento foi proporcional ao aumento da participação dos produtos de levedura. Os índices séricos de ácido úrico, uréia e atividade de transaminases não revelaram sintomas de intoxicação pelo uso dos produtos de levedura. The main objective of this research was to check on the capacity of yeast cells and its derivatives, autolisate and extract, to sustain weaning rats growth, when part of a standard diet for rat growth American Institute of Nutrition-93G was replaced 10, 20 or 30% in proportion of by a mixture (corn starch + yeast product + soy oil) to maintain the substituted diets isoproteic (20% protein) and isocaloric. In the modified diets, the yeast products participate in the diets in concentrations of 4, 8 and 12%, respectively. The diets containing different proportions of yeast product promoted equal or better growth than the standard diet. The growth rate of the rats augmented proportionally to the increase of yeast products in the diets. Blood serum determination of uric acid, urea and transaminases activities showed no evidences of intoxication symptoms by the ingestion of yeast products.

Food industry has been developing products to meet the demands of increasing number of consumers who are concerned with their health and who seek food products that satisfy their needs. Therefore, the development of processed foods that contain functional components has become important for this industry. Microencapsulation can be used to reduce the effects of processing on functional components and preserve their bioactivity. The present study investigated the production of lipid microparticles containing phytosterols by spray chilling. The matrices comprised mixtures of stearic acid and hydrogenated vegetable fat, and the ratio of the matrix components to phytosterols was defined by an experimental design using the mean diameters of the microparticles as the response variable. The melting point of the matrices ranged from 44.5 and 53.4 °C. The process yield was melting point dependent; the particles that exhibited lower melting point had greater losses than those with higher melting point. The microparticles’ mean diameters ranged from 13.8 and 32.2 μm and were influenced by the amount of phytosterols and stearic acid. The microparticles exhibited spherical shape and typical polydispersity of atomized products. From a technological and practical (handling, yield, and agglomeration) points of view, lipid microparticles with higher melting point proved promising as phytosterol carriers.