Tecnologia de Alimentos
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11783
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Item Calcium citrate insolubilization drives the fouling of falling film evaporators during the concentration of hydrochloric acid whey(Food Research International, 2019-02) Tuler-Perrone, I.; Tanguy, G.; Dolivet, A.; Santellani, A.C.; Leduc, A.; Jeantet, R.; Schuck, P.; Gaucheron, F.When dairy powders are produced, the mineral fraction undergoes strong modifications during the vacuum concentration step, leading to the fouling of falling film evaporators. The objective of this study was to determine the nature of the deposits formed during the vacuum concentration of two fouling and highly mineralized products: hydrochloric acid whey and lactic acid whey. These products mainly differ in terms of their mineral composition: lactic acid whey contains a high level of lactic acid and traces of citrate, whereas hydrochloric acid whey contains citrate and no lactic acid. Concentrates at different concentration factors were produced using a pilot-scale falling film evaporator. The compositions of the fouling deposits as well as the precipitates present in the concentrates were deduced from the analytical determination of the composition of the concentrates and their respective diffusible phases. The behavior of the mineral fraction of both acid wheys during concentration was shown to be very different. In the case of hydrochloric acid whey, experimental results suggested a deposition of calcium and citrate ions in the evaporator as well as their precipitation in the highly concentrated products. On the contrary, neither mineral deposition nor precipitation occurred during the concentration of lactic acid whey. This study underlined the key role of citrate ions in the fouling of evaporators during the concentration of hydrochloric acid wheys.Item Comparison of extrusion and co-extrusion encapsulation techniques to protect Lactobacillus acidophilus LA3 in simulated gastrointestinal fluids(LWT, 2018-03) Martins, Evandro; Tulini, Fabrício L.; Silva, Marluci P.; Penning, Manfred; Trindade, Carmen S. Fávaro; Poncelet, DenisThis study aimed to compare two processes for the encapsulation of Lactobacillus acidophilus LA3 using alginate or a blend of alginate–shellac as the wall material and sunflower oil as the core. The particles were dried and stored for up to 60 days at 25 °C for stability studies, and the survival of the encapsulated probiotics in simulated gastrointestinal fluids was evaluated. The viability of the LA3 encapsulated by co-extrusion using alginate or a blend of alginate–shellac was, respectively, 6.2 and 7.2 log CFU/g (colony-forming units per gram), after 60 days of storage, while the viability of the LA3 encapsulated by extrusion was, respectively, 5.3 and 6.2 log CFU/g. The particles produced with the blend of alginate–shellac presented additional protection to the probiotics, as revealed by the increased survival rates in simulated gastrointestinal fluids. Taken together, these data provide a promising alternative for the incorporation of the probiotic L. acidophilus LA3 into new functional foods.Item Conjugates of α-lactalbumin, β-lactoglobulin, and lysozyme with polysaccharides: Characterization and techno-functional properties(Food Research International, 2019-02) Santos, Igor José Boggione; Hernandez, Héctor Luís Hernandez; Costa, Mariana Helena Cardoso; Lafetá Júnior, José Antônio de Queiroz; Coimbra, Jane Sélia dos ReisConjugates of protein (α-lactalbumin, β-lactoglobulin, and lysozyme) with polysaccharides (guar, locust, pectin, and carboxymethilcellulose) were prepared via Maillard reaction by the dry-heating method. The conjugates were characterizated by using the browning index, extent of reaction, grafting degree, sodium dodecyl sulfate – polyacrilamide gel electrophoresis, fluorescence, and circular dichroism. The emulsifying properties and foaming ability of the formed conjugates were also evaluated. Conjugates with pectin and Lz-CMC system showed an increase in the browning index with the increase of the heating time. Circular dichroism and fluorescence data pointed out to conformational changes of proteins during glycation. The lysozyme (lz) conjugates presented the highest degree of glycation (89.1%). The α-Lactalbumin (α-la) - polysaccharides (PS) conjugates showed foam stability higher than the mixture (α-la + PS), the pure α-la, and the conjugates of β-lactoglobulin (β-lg) and lysozyme (lz) for all studied time (30, 60, and 120 min). The α-la-carboxymethylcellulose (CMC) conjugate presented the highest value of foaming stability (85.71). The pure β-lg shows greater foam stability and volume than β-lg-PS conjugates and mixture (β-lg + PS). The lz conjugates do not exihibit foam stability, except for the lz-CMC conjugate that showed stability up to 60 min. Furthermore, emulsion stability of the systems was affected by sonication time. Conjugates of α-la have greatly potencial applications as novel foaming agents in food industry.Item Cultivation of Candida tropicalis in sugar cane hemicellulosic hydrolyzate for microbial protein production(Journal of Biotechnology, 1996-10-18) Pessoa Jr., A.; Mancilha, I. M.; Sato, S.Sugar cane bagasse hemicellulosic fraction was hydrolyzed by treatment with 100 mg of sulfuric acid per gram of dry mass at 140 °C for 20 min. The hydrolyzate was used as the substrate to grow Candida tropicalis IZ 1824 in a 1.0-1 bioreactor at 30 °C; aeration at 1.0 and 2.0 vvm; stirring at 400 rpm and initial pH of 6.0. The kinetic parameters, calculated for both cultivations—at 1.0 and 2.0 wm—included: maximum growth rate (μmax) of 0.057 h−1 and 0.137 h−1, yield of 0.30 and 0.31 g/g and productivity (Qx) of 0.196 g/l per h and 0.202 g/l per h, respectively. The protein produced (31.3% of the total biomass) contains essential amino acids for animal feed.Item Cultivation of Candida tropicalis in sugar cane hemicellulosic hydrolyzate for microbial protein production(Journal of Biotechnology, 1996-09-18) Mancilha, Ismael Maciel de; Pessoa Junior, Adalberto; Sato, SunaoSugar cane bagasse hemicellulosic fraction was hydrolyzed by treatment with 100 mg of sulfuric acid per gram of dry mass at 140 °C for 20 min. The hydrolyzate was used as the substrate to grow Candida tropicalis IZ 1824 in a 1.0-1 bioreactor at 30 °C; aeration at 1.0 and 2.0 vvm; stirring at 400 rpm and initial pH of 6.0. The kinetic parameters, calculated for both cultivations—at 1.0 and 2.0 wm—included: maximum growth rate (μmax) of 0.057 h−1 and 0.137 h−1, yield of 0.30 and 0.31 g/g and productivity (Qx) of 0.196 g/l per h and 0.202 g/l per h, respectively. The protein produced (31.3% of the total biomass) contains essential amino acids for animal feed.Item Dispersed phase hold-up in a Graesser raining bucket contactor using aqueous two-phase systems(Journal of Food Engineering, 2006-02) Coimbra, Jane S. R.; Minim, Luis A.; Rojas, Edwin Elard Garcia; ZuñIga, Abraham Damian GiraldoThis study presents dispersed hold-up data for an aqueous two-phase system containing polyethylene glycol (PEG) 1500 Da and potassium phosphate (PPP) at pH 7 and 25 °C in a Graesser raining bucket contactor. The influences of the operational variables rotor speed and phase flow ratio on the hold-up were analyzed. Densities, viscosities and interfacial tension were measured. The results obtained were correlated by the equation proposed by Richardson and Zaki, for the description of the slip velocities.Item Effect of a health claim on consumer acceptance of exotic Brazilian fruit juices: Açaí (Euterpe oleracea Mart.), Camu-camu (Myrciaria dubia), Cajá (Spondias lutea L.) and Umbu (Spondias tuberosa Arruda)(Food Research International, 2011-08) Vidigal, Márcia C. T. R.; Minim, Valéria P. R.; Carvalho, Naiara B.; Milagres, Maria Patrícia; Gonçalves, Aline C. A.This study evaluates the influence of information on the health benefits for acceptance of four exotic tropical fruit juices: açaí, camu-camu, cajá and umbu. One hundred and six evaluators participated in the tests and sensory acceptability of the four juices in relation to the overall impression was assessed using a hedonic scale of nine points. Testing was conducted in three stages: the first with no information, the second with the information on juice flavor and the last with the information on health benefits from consumption of such juice. Between the second and third session the evaluators were asked to fill out a questionnaire in order to obtain its socioeconomic and cultural profile. It was observed by internal preference mapping that the cajá and umbu juices showed higher sensory acceptance in all sessions. Camu-camu juice had the highest sensory rejection. It was found that the information on the taste of açaí and cajá juices positively influenced consumer acceptance. However the influence of information on health benefits can be observed for all evaluated juices, but despite this information the camu-camu juice continued in the area of sensory rejection (hedonic scores below 5). In the questionnaire it can be observed that the main factor of motivation for consumption of fruit juice is taste, and not the health benefits. It was concluded that the information of health benefits can positively influence sensory acceptance, provided there is sensory pleasure.Item The effect of the association of sanitizers and surfactant in the microbiota of the Cantaloupe (Cucumis melo L.) melon surfac(Food Control, 2005-04) Bastos, Maria do Socorro Rocha; Soares, Nilda de Fátima Ferreira; Andrade, Nélio José de; Arruda, Aline Cristina; Alves, Ricardo ElesbãoThis work aimed to evaluate the efficiency of 200, 500 and 1000 mg l−1 of free available chlorine (FAC) and 60 mg l−1 of peracetic acid (APA) associated or not with Tween 80 in reducing the mesophilic aerobes, coliforms group and fecal coliforms on cantaloupe melon surface. Also, the action of the organic chloramine in removing the Salmonella enteritidis when attached on the melon surface. All treatments reduced significantly (p<0.05) the microbiota analyzed when compared with a water washing, used as control. The treatment with 1000 mg l−1 of organic chloramine with surfactant reduced the mesophilic aerobes (p<0.05) by 4-log cycles, more than the control. Also this chlorine solution was the most efficient in removing S. enteritidis after attachment of the microorganisms to the fruit surface, between 1 and 24 h.Item Foaming properties of suspensions composed by β-lactoglobulin and polysaccharides, in the presence of sucrose or polyols(Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2018-08-05) Vidigal, Márcia Cristina Teixeira Ribeiro; Fidelis, Priscila Cardoso; Minim, Valéria Paula Rodrigues; Minim, Luis Antonio; Faria, Janaína Teles de; Neves, Isabelle Cristina OliveiraThis study compares the effect of different combinations between β-lactoglobulin (β-lact, 1.0–1.5% w/v), a polysaccharide (carrageenan gum, CG, or locust bean gum, LBG, 0.0–0.5% w/v) and a sweetener (sucrose, maltitol or sorbitol, 0.0–0.5% w/v) on the foaming capacity and half-life time. The experimental design was defined according to a simplex centroid mixture design with a restriction of at least 1.0% w/v of β-lact in each mixture. Measurements of particle size, zeta potential, surface tension, flow curve, foaming capacity and foam half-life time were obtained. All mixtures evaluated showed a wide particle size distribution with diameters between 5.35 and 4494 nm. Mixtures containing CG presented higher values for apparent viscosity and average particle size than mixtures containing LBG, according to the gum concentration in solution. All mixtures showed negative zeta potential values (−14.27 to −40.42 mV) due to the presence of negatively charged β-lact at the pH 7. However, CG exerted a dominant effect on the zeta potential when present in the mixtures. The surface tension and foaming capacity were affected by the combined effect of the gums and sweeteners used. These molecules seemed to concentrate the protein at the interface due to the exclusion volume effect. The foam half-life time was mainly improved by the CG due to the higher bulk apparent viscosity, regardless of the sweetener used. Replacing sucrose with maltitol or sorbitol lead to comparable foam characteristics, mainly the foam capacity and foam half-life time, which confirms the potential of these polyols for sucrose replacement in model foams.Item How the presence of a small molecule affects the complex coacervation between lactoferrin and β-lactoglobulin(International Journal of Biological Macromolecules, 2017-09) Tavares, Guilherme M.; Croguennec, Thomas; Hamon, Pascaline; Carvalho, Antônio F.; Saïd BouhallabHeteroprotein complex coacervation corresponds to the formation of two liquid phases in equilibrium induced by the interaction of two oppositely charged proteins. The more concentrated phase known as coacervate phase, has attracted interest from several fields of science due to its potential applications for example for encapsulation and delivery of bioactives. Prior such application, it is necessary to understand how the presence of small ligands affects the complex coacervation. In this work, we report on the interaction of small ligand with individual proteins β-lactoglobulin (β-LG) and lactoferrin (LF) and consequences on their complex coacervation. ANS (8-Anilinonaphthalene-1-sulfonic acid), a fluorescent probe, was used as model ligand. While ANS did not interact with β-LG, it presented two sets of binding sites with LF inducing its self-aggregation. Depending on its concentration, ANS modulated the shape of β-LG-LF macromolecular assembly. Coacervates were observed for ANS/LF molar ratio <25 against amorphous aggregates for higher ANS/LF molar ratios. A maximum loading capacity of around 40 mg of ANS per gram of LF in the formed heteroprotein coacervates was reached.Item Insights on physicochemical aspects of chitosan dispersion in aqueous solutions of acetic, glycolic, propionic or lactic acid(International Journal of Biological Macromolecules, 2019-05-01) Soares, Lucas de Souza; Perim, Rayza Badiani; Alvarenga, Elson Santiago de; Guimarães, Luciano de Moura; Teixeira, Alvaro Vianna Novaes de Carvalho; Coimbra, Jane Sélia dos Reis; Oliveira, Eduardo Basílio deChitosan is a polysaccharide well-known for its applicability as a biocompatible, biodegradable, and non-toxic material to produce drugs excipients and food coatings. Acidic media are required to disperse chitosan, and aqueous solutions of acetic acid have been typically used for this purpose. However, this acid has several sensory drawbacks. In this study, chitosan was dispersed [0.1 g·(100 mL)−1] in aqueous media containing acetic (AA), glycolic (GA), propionic (PA), or lactic (LA) acid, at 10, 20, 30, 40, or 50 mmol·L−1. The increase of acid concentration reduced pH and viscosity of the dispersions, and |ζ potential| of dispersed particles. Conversely, it increased electrical conductivity and density of the dispersions, and hydrodynamic diameter of dispersed particles. At a given concentration, these effects were slightly more pronounced for dispersions formed with GA or LA, compared to AA or PA. FT-IR data suggested more intense attractive interactions of chitosan chains with glycolate and lactate anions, than with acetate and propionate. Chitosan chains interacted more strongly with hydroxylated acids counter-anions than with their non-hydroxylated counterparts, leading to slight quantitative changes of physicochemical properties of these systems. Then, in physicochemical terms, GA, LA or PA are suitable to replace AA when preparing aqueous chitosan dispersions for technological applications.Item Microencapsulation by atomization of the mixture of phenolic extracts(Powder Technology, 2019-02) Rocha, Juliana de Cássia Gomes; Barros, Frederico Augusto Ribeiro de; Viana, Kéllen Wanessa Coutinho; Stringheta, Paulo César; Perrone, Ítalo Tuler; Tavares, Guilherme Miranda; Stephani, RodrigoBlends of jabuticaba, jussara and blueberry phenolic extracts were microencapsulated by spray drying using maltodextrin, gum arabic and whey protein concentrate (WPC) as the wall materials. Drying was performed with 10 different combinations of wall material mixtures (M1-M10). The samples, M1, M2 and M3, microencapsulated with the individual wall materials, maltodextrin, WPC and gum arabic, respectively, provided the highest encapsulation efficiency of anthocyanins. Furthermore, M1 and M2 presented the lowest hygroscopicity, while the mixtures containing WPC displayed the lowest solubility. All wall materials influenced the colour of the microcapsules, due to the different pH values of each encapsulated blend. The M2 blend was classified as a finished product and could be marketed as a high value-added protein concentrate, whereas, the other blends were considered natural colourants, with potential application in the food and cosmetics industry.Item Role of structural ions on the dynamics of the Pseudomonas fluorescens 07A metalloprotease(Food Chemistry, 2019-07-15) Alves, Maura P.; Eller, Monique R.; Carvalho, Antonio Fernandes de; Ligabue-Braun, Rodrigo; Polêto, Marcelo D.The molecular dynamics of the Pseudomonas fluorescens 07A metalloprotease in the presence of structural Ca2+ and Mn2+ ions was evaluated. Seven Ca2+ ions are primarily bound to the C-terminus, while a divalent cation is located at the catalytic site, acting as a cofactor. The observed enzyme’s experimental activity suggests that Mn2+ could compete for the active site of the enzyme with Ca2+, Zn2+ or other divalent cations, thus providing greater catalytic power to the enzyme. Our molecular dynamics simulations suggest that these ions partially protect the enzyme’s structure from thermal denaturation. Moreover, our simulations have shown a collective movement of opening-closing of the active-site in simulations with structural Ca2+ and Mn2+ ions bound, leading to a proposal of a dynamical model of P. fluorescens 07A metalloprotease active and inactive conformations. These findings can support the development of measures to control the activity of P. fluorescens and other spoilage microorganism proteases.