Microencapsulação de óleo essencial de capim limão utilizando o processo de coacervação simples

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia Química.A microencapsulação é capaz de aumentar o tempo de vida útil de compostos voláteis, presentes em produtos alimentícios e cosméticos. No presente trabalho são apresentados os resultados da microencapsulação do óleo essencial de capim limão (Cymbopogom citratus) com poli(álcool vinílico) reticulado com glutaraldeído através da técnica de coacervação simples ou salting out. Foram avaliados quatro tipos de PVA com diferentes massas molares e graus de hidrólise. Os resultados experimentais mostraram que PVAs de elevado grau de hidrólise apresentam baixa ativação superficial, não estabilizando o óleo essencial e não formando microcápsulas. A distribuição de tamanho das microcápsulas apresentou estreitamento e deslocamento para faixas de diâmetro menores com o aumento da temperatura de reação, com a diminuição da fração volumétrica e com o aumento da taxa de agitação. A absorção de água, ou intumescimento, das microcápsulas foi diminuída com o aumento da razão de reticulação utilizada. A adição de nitrogênio ao meio de reação foi avaliada e os resultados indicaram que a taxa de reação foi maior. Foram testados um estabilizante, poli(pirrolidona vinílica) e um surfactante, dodecil sulfato de sódio, para evitar a reticulação entre as microcápsulas. Somente o dodecil sulfato de sódio mostrou-se eficiente. O óleo essencial de capim limão foi avaliado antes e após ser microencapsulado quanto a sua composição e atividade antimicrobiana, avaliada por concentração mínima inibitória. Não foram observadas alterações que pudessem comprometer a sua atividade antimicrobiana. A liberação do óleo essencial microencapsulado foi avaliada por hidrodestilação das microcápsulas e foi comparada à hidrodestilação do óleo essencial puro mostrando que o óleo encapsulado é liberado a uma taxa menor. Por fim o glutaraldeído foi quantificado através de HPLC em função do tempo de reação, mostrando que sua maior parte é consumida na primeira hora de reação

MODELLING THE MELTING TEMPERATURE OF A LIPID‐BASED CRITICAL TEMPERATURE INDICATOR: A COMPARISION BETWEEN SIMPLEX-LATTICE AND SIMPLEX-CENTROID DESIGNS

Critical temperature indicators (CTI) find applications in food industry in cases when defrost may not occur or a specific temperature may not be reached, , indicating changes through visual changes, such as melting, color changes, etc. Lipid mixtures are promising candidates to formulate CTI since the final melting point of the mixture may be manipulated by the proportion of each lipid. In this work a lipid mixture consisting of stearic acid, lard and peanut oil was used to develop a CTI mixture. Simplex-lattice and Simplex-centroid experimental designs were compared to modelling the melting temperature of the lipid mixture. Addition of axial points to the experimental design improved predictive ability of the models while the inclusion of inverse terms was necessary to improve models accuracy. Simplex-lattice design presented an improved ability to predict the melting point of binary mixtures, while the simplex-centroid design resulted in an improved model for predicting melting point of the ternary mixture

Improvement of sensorial and volatile profiles of olive oil by addition of olive leaves

The changes caused by the addition of olive leaves (0, 5, and 10%) during the extraction of olive oil and malaxation time (20, 30, and 30 min) in the volatile profile and sensory attributes of olive oil from cv. Cobrançosa were studied. To investigate such transformations, a central composite designs from the Response Surface Methodology (RSM) was used, retrieving 13 runs combining leaf percentages and malaxation times. Each run was extracted in triplicate (39 olive oils overall). Sensory attributes were improved to leaves addition, mainly green and fruitiness attributes in olfactory and gustatory-olfactory sensations, but high malaxation times ( > 30 min) reduced pungent and bitter notes. Leaves addition increased the amounts of total volatiles, particularly the GLV's (green leaves volatiles) (E)-2-hexenal, (Z)-3-hexenal, and (Z)-3-hexenyl acetate, directly correlated with the improved sensory attributes. RSM models a showed positive linear effect with leaves addition, but a negative effect with malaxation time. These results suggest the use of olive leaves as effective odorants for the olive mill industry, while enabling the reduction of malaxation times and by-product amounts. Practical applications: The results obtained clearly open new lines of research to use olive leaves, a sub-product of olive oil extraction, in a valuable way. Olive leaves can be used as natural sources of odorants for olive oils. Furthermore, their use during the extraction of olive oils from overmature olives may also lead to an improvement of the volatile fraction and provide enhanced sensory properties to the consumers, thus conferring an added value to these oils. Another important practical application is the extraction process. In our work, we advise to optimize both the percentage of leaves and the malaxation time as much as possible, as they facilitate both sensory and volatile fractions of the extracted olive oils. Sensory attributes are improved to leaves addition, mainly green and fruitiness attributes in olfactory 17 and gustatory-olfactory sensations, but high malaxation times ( > 30 min) reduced pungent and bitter 18 notes. Leaves addition increase the amounts of total volatiles, particularly the GLV's (green leaves 19 volatiles) (E)-2-hexenal, (Z)-3-hexenal, and (Z)-3-hexenyl acetate, directly cor related with the improved 20 sensory attributes. RSM models a show positive linear effect with leaves addition, but a negative effect 21 with malaxation time. These results suggest the use of olive leaves as effective odorants for the olive mill 22 industry, while enabling the reduction of malaxation times and by-product amounts.Ricardo Malheiro thanks FCT, POPH-QREN and FSE for the Post-Doctoral grant (SFRH/BPD/111901/2015).info:eu-repo/semantics/publishedVersio

Heat and pH stable curcumin-based hydrophylic colorants obtained by the solid dispersion technology assisted by spray-drying

Natural food colorants are on demand due to food safety concerns related with some synthetic counterparts. Health-friendly alternatives can be available from plant sources, which include curcumin extracted from Curcuma longa L. However, its industrial use is difficult to achieve due to the low water affinity, pH and thermal instability, which is particularly challenging, e.g. for baked foods. In this work, the solid dispersion technique followed by spray-drying, an emergent approach in the context of colorants, was applied to curcumin using k-carrageenan, poly(vinyl alcohol) and polyvinylpyrrolidone, as the encapsulant materials. An orthogonal central composite design with dummy-variables was applied, and principal component analysis (PCA) and hierarchical cluster analysis (HCA) carried out to identify the experimental conditions leading to the most effective formulations. In general, particles with a wide range of pH and heat stability have been produced depending on the chosen encapsulant material, used formulation (curcumin, surfactant and polymer contents), and synthesis conditions (pH). Moreover, the used mathematical approach showed to be a valuable tool to support the development of tailor-made formulations directed to specific applications where pH and temperature are relevant processing parameters.This work was financially supported by Associate Laboratory LSRE-LCM (UID/EQU/50020/2019) funded by national funds through FCT/MCTES (PIDDAC), and Foundation for Science and Technology (FCT, Portugal). CIMO (UID/AGR/00690/2019) through FEDER under Program PT2020. Authors thank CAPES (Brazil), CNPq (Brazil) and Fundação Araucária (Brazil) for the support.info:eu-repo/semantics/publishedVersio

Tailoring swelling of alginate-gelatin hydrogel microspheres by crosslinking with calcium chloride combined with transglutaminase

lginate-based hydrogels can find uses in a wide range of applications, including in the encapsulation field. This type of hydrogels is usually ionically crosslinked using calcium sources giving rise to products with limited internal crosslinking. In this work, it is hypothesized that the combination of alginate crosslinked by calcium chloride (external crosslinking; ionic mechanism) with gelatin crosslinked by transglutaminase (internal crosslinking; enzymatic induced mechanism) can be used to tailor the swelling behavior of alginate-based hydrogel microspheres. A systematic study was conducted by covering process variables such as gelatin content, TGase concentration, and CaCl2 contact time, added by statistic tools as central composite rotatable design (CCRD), principal component analysis (PCA) and multiobjective optimization, to map their effect on the resulting water content after production (expressed as swelling ratio), and swelling properties at pH 3 and 7. Among the studied variables, particle's swelling was mostly affected by the gelatin content and transglutaminase concentration.This work was financially supported by Associate Laboratory LSRELCM (UID/EQU/50020/2019) funded by national funds through FCT/ MCTES (PIDDAC), and Foundation for Science and Technology (FCT, Portugal) and by CIMO (UID/AGR/00690/2019) trough FEDER under Program PT2020. The authors are grateful to CAPES, CNPq and Fundação Araucária for the support and also to Ajinomoto Foods Europe S.A.S. (France) for kindly provide the transglutaminase sample used in this work. I.P. Fernandes thanks the national funding by FCT, P.I., through the institutional scientific employment program-contract for her contract.info:eu-repo/semantics/publishedVersio

Water-in-oil-in-water double emulsions as protective carriers for Sambucus nigra l. coloring systems

The use of natural colorants is needed to overcome consumer concerns regarding synthetic food colorants0 safety. However, natural pigments have, in general, poor stability against environmental stresses such as temperature, ionic strength, moisture, light, and pH, among others. In this work, water-in-oil-in-water (W1/O/W2) emulsions were used as protective carriers to improve color stability of a hydrophilic Sambucus nigra L. extract against pH changes. The chemical system comprised water and corn oil as the aqueous and oil phases, respectively, and polyglycerol polyricinoleate (PGPR), Tween 80, and gum Arabic as stabilizers. The primary emulsion was prepared using aW1/O ratio of 40/60 (v/v). For the secondary emulsion,W1/O/W2, different (W1/O)/W2 ratios were tested with the 50/50 (v/v) formulation presenting the best stability, being selected as the coloring system to test in food matrices of different pH: natural yogurt (pH 4.65), rice drink (pH 6.01), cow milk (pH 6.47), and soy drink (pH 7.92). Compared to the direct use of the extract, the double emulsion solution gave rise to higher color stability with pH change and storage time, as corroborated by visual and statistical analysis.FCT/MCTES for financial support to CIMO (UIDB/00690/2020). National funding by FCTFoundation for Science and Technology, through the institutional scientific employment programcontract of A. Fernandes, I. Fernandes, and L. Barros. Valor Natural project (Project Norte-01-0247- FEDER-024479).info:eu-repo/semantics/publishedVersio

Antibacterial efficacy of Enterococcus microencapsulated bacteriocin on Listeria monocytogenes, Listeria innocua and Listeria ivanovi

This study focused on the microencapsulation of enterocin from Enterococcus durans (E. durans MF5) in whey powder (WP) using a spray-drying technique followed by the evaluation of how complexation can preserve the enterocin structure and antimicrobial activity against foodborne pathogens. Crude enterocin samples (1 and 5%) were microencapsulated in 10% WP. The antimicrobial activity of unencapsulated (crude) enterocin and microencapsulated enterocin was tested against the target bacteria Salmonella Typhimurium, Escherichia coli, Listeria monocytogenes, Listeria innocua, and Listeria ivanovi. The microencapsulation yields were 31.66% and 34.16% for concentrations of 1 and 5% enterocin, respectively. There was no significant difference between these concentrations. Microencapsulated enterocin was efficient for up to 12 h of cocultivation with Listeria sp., and the concentration required to inhibit the growth of target bacteria presented values of 6400 AU/ mL (arbitrary unit). Microencapsulated enterocin demonstrated enhanced efficacy against Listeria species and E. coli when compared with crude enterocin (p < 0.05). Fourier transform-infrared spectroscopy and differential scanning calorimetry results confirmed the presence of enterocin in the microparticles. Scanning electron microscopy showed cell damage of the target bacteria. The results showed that complexation with WP preserved enterocin antimicrobial activity during spray-drying, indicating its potential use as a food preservative.This work was supported by Fundação Araucária/Governo do Paraná—Brazil, UTFPR-Londrina Campus and State University of Londrina-Paraná. The authors thank the “Central Analítica Multiusuário da UTFPR Campo Mourão (CAMulti-CM)¨ and “Laboratório Multiusuário da UTFPR Campus Londrina (LabMulti-LD)¨ for the analyses. Fernanda V. Leimann (process 039/2019) thanks to Fundação Araucária (CP 15/2017- Programa de Bolsas de Produtividade em Pesquisa e Desenvolvimento Tecnológico) and to CNPq (process number 421541/2018-0, Chamada Universal MCTIC/CNPq n.° 28/2018).info:eu-repo/semantics/publishedVersio

Chemometric evaluation of enzymatic hydrolysis in the production of fish protein hydrolysates with acetylcholinesterase inhibitory activity

Fish protein hydrolysates (FPH) obtained from industrial processing residues are sources of bioactive peptides. The enzymatic hydrolysis process is essential in obtaining specific bioactivities such as inhibition of the enzyme acetylcholinesterase (AChE). In this study the effect of different hydrolysis conditions on the properties of FPH to inhibit the enzyme acetylcholinesterase. A chemometric evaluation, based on a central composite rotatable design and principal component analysis, was applied to select hydrolysis conditions with best yield, degree of hydrolysis and acetylcholinesterase inhibition. Experimental design results for AChE inhibition were between 10.51 and 40.45% (20, 30 and 50 mg.mL-1 of FPH), and three hydrolysis conditions were selected based on PCA evaluation. The amino acids profile, FTIR and AChE inhibition kinetics were evaluated. Results showed a mixed type of inhibition behavior and, the docking molecular analyzes suggest that the inhibition AChE occurred due to the basic amino acids, mainly by arginine.Authors thank to CNPq (Chamada Universal– MCTI/CNPq N◦ 28/2018, Process 421541/2018-0) and Fundação Araucária (convênios 40/2016, 53/2019 and 039/2019) for the financial support. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001. Authors thank to Central Analítica Multiusu´ario da UTFPR Campo Mour˜ao (CAMulti-CM) by the analysis.info:eu-repo/semantics/publishedVersio

Chemometric approaches to evaluate the substitution of synthetic food dyes by natural compounds: The case of nanoencapsulated curcumin, spirulina, and hibiscus extracts

Finding natural food coloring options from plant-based sources to substitute artificial dyes is a challenging task because natural dyes often present low water-solubility, not very vibrant hues, and instability due to interactions with food ingredients. Chemometric approaches can be used to evaluate color differences and patterns resulting from natural and synthetic dyes when applied to food systems. Here, the Mixture Design and the Principal Component Analysis (PCA) were applied to evaluate the substitution of the following artificial food dyes: yolk yellow, apricot yellow, strawberry red, and tartrazine by natural dyes (water-soluble curcumin, yellow shade; Hibiscus sabdariffa extract, red shade; Spirulina platensis extract, blue/green shade), in three food simulated systems (phosphate buffer, pH 6.9; yogurt, pH 4.0 and citrate buffer, pH 3.0). The color parameters L*, a*, b*, C* and °h were determined and color difference (ΔE*) with artificial dyes resulted in 11 empirical models. PCA yielded a clear map for the identification of the closely matches natural/artificial dyes for the food simulated systems in three subregions. Furthermore, the antioxidant capacity of the natural dyes was determined by OxHLIA and TBARS. It was possible to make an assessment guide that may be useful for other food systems and dyes.Authors thank to CNPq (Chamada Universal– MCTI/CNPq Nº 28/2018, Process 421541/2018–0) and Fundação Araucária (convênio 039/2019) for the financial support. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001. Authors thank to Central Analítica Multiusuário da UTFPR Campo Mourão (CAMulti-CM) by the color analysis. Authors are grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to the CIMO (UIDB/00690/2020). L. Barros and C. Pereira thank the national funding by FCT, P.I., through the institutional scientific employment program-contract for their contracts.info:eu-repo/semantics/publishedVersio

Encapsulation of clove oil in nanostructured lipid carriers from natural waxes: Preparation, characterization and in vitro evaluation of the cholinesterase enzymes

Eugenol is a phenolic compound largely found in the clove essential oil that possesses promising biological activity. However, its low water solubility is a major concern and encapsulation is an alternative to improve water affinity. The objective of this work was to produce nanostructured lipid carriers (NLC) by hot homogenization/ultrasound emulsification and to evaluate the effect of free and encapsulated clove oil on the in vitro cholinesterase enzymes modulation using Drosophila melanogaster (DM) tissue. The NLC composed of a natural wax (carnauba or beeswax) and crodamol showed an average diameter between 121 and 367 nm with good dispersion and colloidal stability. The spherical shape and solid character together with the semi-crystalline environment confirm the formation of NLC. DSC analysis indicated polymorphic transition events of the waxes. In vitro tests using DM demonstrated that free clove oil showed a good inhibition of the butyryl and acetylcholinesterase enzymes above a concentration of 10 mM, with IC50 values of 4.3 and 3.5 mM, respectively. The dispersions of the NLC loaded with clove oil showed a decrease in the IC50 enzymes values, indicating the preservation of the clove essential oil and suggesting an increased in the solubility. Results indicate that NLC dispersions have good potential to be used for foods and cosmetic aqueous formulations possessing biological activity.Authors thank the financial support from CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) and CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico), and also Laboratório Central de Microscopia Eletrônica of Universidade Federal de Santa Catarina (LCME/UFSC) for TEM analyses.info:eu-repo/semantics/publishedVersio