Effects of the geometry of reinforcement on physical properties of sodium caseinate/TiO2 nanocomposite films for applications in food packaging.

Plastic materials for food packaging are being replaced by biodegradable films based on biopolymers due to the adverse effects they have had on animal life and the environment. In this study, nanocomposite films containing 2.5 wt% sodium caseinate and 2 wt% glycerol were reinforced with 0.1 or 0.2 wt% nano TiO2 prepared in two forms: spheres (P25) and tubes. The effects of nanoreinforcement geometry on mechanical, tensile, barrier, thermogravimetric, and optical properties, and distribution of nanoparticles were described. The interactions among film components were analyzed by Fourier transform infrared spectroscopy (FTIR). Addition of nanotubes significantly increased E' (341 wt%) and E" (395 wt%) moduli, the Young modulus E (660 wt%), the residual mass at 500°C (38 wt%), and color change (6.78) compared to control film. The compositional mapping studies showed that P25 nanoparticles were homogeneously distributed between the surfaces of the film while nanotubes were found on the bottom surface. The changes in position of the FTIR spectra signals as compared to pure protein signals indicated strong matrix/reinforcement interactions. In addition, the changes in intensity in 1100, 1033, and 1638 cm-1 FTIR signals suggested formation of a protein/Tween 20 ester. The geometry of reinforcement was highly relevant regarding physical properties, showing nanotubes as being very successful for enhancing tensile properties.

Obtention of Sacha Inchi (Plukenetia volubilis Linneo) Seed Oil Microcapsules as a Strategy for the Valorization of Amazonian Fruits: Physicochemical, Morphological, and Controlled Release Characterization.

Sacha inchi seed oil (SIO) is a promising ingredient for the development of functional foods due to its large amount of high-value compounds; however, it is prone to oxidation. This work aimed to obtain SIO microcapsules using conventional and ultrasound probe homogenization and using spray- and freeze-drying technologies as effective approaches to improve the long-term stability of functional compounds. The application of ultrasound probe homogenization improved the rheological and emulsifying properties and decreased the droplet size and interfacial tension of emulsions. The microcapsules obtained by both drying technologies had low moisture (1.64-1.76) and water activity (0.03-0.11) values. Spray-dried microcapsules showed higher encapsulation efficiency (69.90-70.18%) compared to freeze-dried ones (60.02-60.16%). Thermogravimetric analysis indicated that heat protection was assured, enhancing the shelf-life. Results suggest that both drying technologies are considered effective tools to produce stable microcapsules. However, spray-drying technology is positioned as a more economical alternative to freeze-drying.

Lutein bioaccessibility in casein-stabilized emulsions is influenced by the free to acylated carotenoid ratio, but not by the casein aggregation state.

Considering that carotenoids are found acylated to fatty acids in most edible fruits, the influence of the ratio of free to acylated lutein on the hydrolysis extent and bioaccessibility was evaluated by in vitro digestion. For this purpose, for the first time, esterified, free, or a mixture of both carotenoid forms was used in the lipid phase of emulsions stabilized by sodium caseinate (NaCas) and native phosphocaseinate (PPCN). Marigold petals was used as a source of lutein-rich extracts. The emulsions were characterized and the extent of ester hydrolysis, carotenoid recovery, and bioaccessibility were evaluated by LC-DAD-MS/MS. Besides low polydispersity, NaCas and PPCN stabilized emulsions exhibited a constant mean droplet diameter of about 260 and 330 nm, respectively, after 7 days. Caseins were completely digested after the gastric digestion step. Moreover, casein supramolecular structure did not significantly affect carotenoid bioaccessibility. Lutein was majorly found in its free form in all bioaccessible fractions. The carotenoid bioaccessibility increased from 3% to 40% by increasing the percentage of free carotenoids from 0.5 to 100% in the emulsions; but the carotenoid recovery and hydrolysis extent of lutein esters were not affected. In conclusion, emulsion-based systems for carotenoid delivery stabilized either by NaCas or PPCN provided similar carotenoid bioaccessibility. Furthermore, bioaccessibility was inversely dependent on the overall hydrophobicity of the carotenoid extract. Our results suggest that the low bioaccessibility of esterified carotenoids was a consequence of their limited hydrolysis extent. This study provides information that may help design emulsion-based systems stabilized by food protein as a vehicle for carotenoids.

Development of Biodegradable Films Loaded with Phages with Antilisterial Properties.

The inhibitory and bactericidal capacity of Listex P100 bacteriophage has been studied against different concentrations of Listeria monocytogenes in stationary and exponential phases. Three different matrices were employed to developed films incorporating Listex P100: (1) sodium caseinate, (2) sodium alginate mixed with gelatin, and (3) polyvinyl alcohol (PVOH). All the films were successfully developed by casting at room temperature. These active biodegradable films were optical, structural, and thermally characterized, and their antimicrobial capacities against L. monocytogenes were studied. The incorporation of phages did not affect the morphology, colour, opacity, and thermal stability of polymers. The antimicrobial analysis revealed the bacteriophage presented a high antimicrobial capacity against L. monocytogenes in the stationary phase (4.40 and 6.19 log reduction values or bactericide effect depending on the initial inoculum of the pathogen). Developed films showed antimicrobial capacity close to 1 log after 24 h of incubation at 30 °C. The effectiveness of PVOH films was greater under refrigeration conditions, reaching 2 log reduction after eight days of incubation. The use of these films as a coating in a food or as part of a packaging could improve food safety against the growth of pathogenic microorganisms such as Listeria monocytogenes.

Unraveling the molecular mechanisms underlying interactions between caseins and lutein.

Understanding the food protein binding to bioactive compounds is of utmost importance for the development of efficient protein-based delivery systems. The binding of lutein to sodium caseinate (NaCas) or native casein micelle (PPCN) was investigated at pH 7 to evaluate the effect of casein supramolecular structures on the interaction. Fluorescence quenching, UV-vis spectroscopy, and dynamic light scattering were carried out. Under the medium conditions of interaction analysis (DMSO-water and ethanol-water), lutein exists as H-type aggregates. The investigation of lutein/casein interaction showed a predominantly static mechanism of fluorescence quenching and the presence of two fluorophore populations on NaCas and PPCN, but only one accessible to lutein. Moreover, the Scatchard plot indicated that lutein interacted with both caseins in one binding site. The interaction of lutein with caseins occurred with binding constant Kb of 105 M-1, regardless of casein supramolecular structure.

Effect of Ohmic heating on functionality of sodium caseinate - A relationship with protein gelation.

Sodium caseinate (NaCAS) is widely used in the food industry to provide nutritional and functional benefits. This work deals with the effects of applying moderate electric fields (MEF) of different intensity - ranging from 2 V·cm-1 to 17 V·cm-1 - on the physical and functional properties of NaCAS solutions during Ohmic heating (OH) at 95 °C. Self-standing gels were produced regardless the heating technique applied (i.e. conventional or OH), and these gels were much more prone to physical rupture when compared with the ones produced from unheated NaCAS. Interestingly, OH treatment formed gels with lower values of strain at rupture and water holding capacity than unheated samples; this pattern was not observed for gels obtained through the conventional heating treatment (at 0 V·cm-1). These effects may be linked with disturbances of the distribution of random coil structures and enhanced solubility of NaCAS at its isoelectric point, reducing aggregation and impairing the development of a more compact protein network. Results show that OH presents potential to be used as volumetric heating tool for NaCAS solubilization and for the production of distinctive acidified systems.

pH- and ionic strength-dependent interaction between cyanidin-3-O-glucoside and sodium caseinate.

Understanding the mechanism of interaction between food proteins and bioactives constitutes the preliminary step to design food grade nanocarriers. We investigated the interaction between cyanidin-3-O-glucoside (C3G), and 20nm-sized sodium caseinate nanoparticles (NaCas) at pH 7 and pH 2 by fluorescence spectroscopy and dynamic light scattering. The characterization of the C3G-NaCas interaction indicated that the fluorescence quenching mechanism was predominantly static. C3G interacted with two sets of binding sites with association constants Ka of 106 and 105M-1. Electrostatic interactions dominated at pH 7, while hydrophobic effects were the main force at pH 2. Interestingly, the two sets of binding sites were discriminated by ionic strength at pH 7. The binding of C3G slightly modified the average diameter of NaCas nanoparticles without alteration of its surface charge suggesting a complexation of C3G molecules in the internal casein structure. Thus, NaCas constitutes a putative nanocarrier for anthocyanins in new functional foods.

Relationship between nano/micro structure and physical properties of TiO2-sodium caseinate composite films.

Films obtained by casting, starting from conventional emulsions (CE), nanoemulsions (NE) or their gels, which led to different structures, with the aim of explore the relationship between structure and physical properties, were prepared. Sodium caseinate was used as the matrix, glycerol as plasticizer, glucono-delta-lactone as acidulant to form the gels, and TiO2 nanoparticles as reinforcement to improve physical behavior. Structural characterization was performed by SAXS and WAXS (Small and Wide Angle X-ray Scattering, respectively), combined with confocal and scanning electron microscopy. The results demonstrate that the incorporation of the lipid phase does not notably modify the mechanical properties of the films compared to solution films. Films from NE were more stable against oil release than those from CE. Incorporation of TiO2 improved mechanical properties as measured by dynamical mechanical analysis (DMA) and uniaxial tensile tests. TiO2 macroscopic spatial distribution homogeneity and the nanostructure character of NE films were confirmed by mapping the q-dependent scattering intensity in scanning SAXS experiments. SAXS microscopies indicated a higher intrinsic homogeneity of NE films compared to CE films, independently of the TiO2 load. NE-films containing structures with smaller and more homogeneously distributed building blocks showed greater potential for food applications than the films prepared from sodium caseinate solutions, which are the best known films.

Colloidal properties of sodium caseinate-stabilized nanoemulsions prepared by a combination of a high-energy homogenization and evaporative ripening methods.

Nanoemulsions stabilized by sodium caseinate (NaCas) were prepared using a combination of a high-energy homogenization and evaporative ripening methods. The effects of protein concentration and sucrose addition on physical properties were analyzed by dynamic light scattering (DLS), Turbiscan analysis, confocal laser scanning microscopy (CLSM) and small angle X-ray scattering (SAXS). Droplets sizes were smaller (~100nm in diameter) than the ones obtained by other methods (200 to 2000nm in diameter). The stability behavior was also different. These emulsions were not destabilized by creaming. As droplets were so small, gravitational forces were negligible. On the contrary, when they showed destabilization the main mechanism was flocculation. Stability of nanoemulsions increased with increasing protein concentrations. Nanoemulsions with 3 or 4wt% NaCas were slightly turbid systems that remained stable for at least two months. According to SAXS and Turbiscan results, aggregates remained in the nano range showing small tendency to aggregation. In those systems, interactive forces were weak due to the small diameter of flocs.

Physicochemical study of mixed systems composed by bovine caseinate and the galactomannan from Gleditsia amorphoides.

Model systems formed by sodium caseinate (NaCAS) and espina corona gum (ECG) were studied. There was no evidence of attractive interactions between NaCAS and ECG macromolecules. Aqueous mixtures of NaCAS and ECG phase-separate segregatively over a wide range of concentrations. According to the images obtained by confocal laser scanning microscopy, NaCAS particles form larger protein aggregates when ECG is present in the system. An increase in the hydrodynamic diameter of NaCAS particles, as a result of ECG addition, was also observed by light scattering in diluted systems. A depletion-flocculation phenomenon, in which ECG is excluded from NaCAS surface, is proposed to occur in the concentrated mixed systems, resulting in NaCAS aggregation. ECG raises the viscosity of NaCAS dispersions without affecting the Newtonian flow behaviour of NaCAS. These results contribute to improve the knowledge of a barely-studied hydrocolloid which may be useful in the development of innovative food systems.

Heteroaggregation of lipid droplets coated with sodium caseinate and lactoferrin.

Formation and characterization of droplet heteroaggregates were investigated by mixing two emulsions previously stabilized by proteins oppositely charged. Emulsions were composed of 5vol.% of sunflower oil and 95vol.% of sodium caseinate or lactoferrin aqueous dispersions. They were produced using ultrasound with fixed power (300W) and sonication time (6min). Different volume ratios (0-100%) of sodium caseinate-stabilized emulsion (droplet diameter around 1.75µm) to lactoferrin-stabilized emulsion (droplet diameter around 1.55µm) were mixed under conditions that both proteins showed opposite charges (pH7). Influence of ionic strength (0-400mM NaCl) on the heteroaggregates stability was also evaluated. Creaming stability, zeta potential, microstructure, mean particle diameter and rheological properties of the heteroaggregates were measured. These properties depended on the volume ratio (0-100%) of sodium caseinate to lactoferrin-stabilized emulsion (C:L) and the ionic strength. In the absence of salt, different zeta potential values were obtained, rheological properties (viscosity and elastic moduli) were improved and the largest heteroaggregates were formed at higher content of lactoferrin-stabilized emulsion (60-80%). The system containing 40 and 60vol.% of sodium caseinate and lactoferrin stabilized emulsion, respectively, presented good stability against phase separation besides showing enhanced rheological and size properties due to extensive droplets aggregation. Phase separation was observed only in the absence of sodium caseinate, demonstrating the higher susceptibility of lactoferrin to NaCl. The heteroaggregates produced may be useful functional agents for texture modification and controlled release since different rheological properties and sizes can be achieved depending on protein concentrations.

Qualidade físico-química e atividades biológicas de caseinofosfopeptídeos obtidos por hidrólise tríptica de caseinato de sódio sob diferentes condições / Physico-chemical quality and biological activities of Casein phosphopeptides obtained by sodium caseinate tryptic hydrolysis under different conditions

Muitos métodos têm sido empregados na produção de peptídeos bioativos para a promoção da saúde. O objetivo deste estudo foi produzir caseinofosfopeptídeos por hidrólise tríptica do caseinato de sódio usando diferentes temperaturas (37 e 50 °C) e tempos de reação (2 e 4 h), caracterizá-los e analisar sua influência nas atividades citotóxica, antimicrobiana e antioxidante. Caseinofosfopeptídeos foram caracterizados através da composição centesimal, eletroforese em gel de poliacrilamida, Espectrometria de Massas e Cromatografia Líquida de Alta Eficiência. Toxicidade para leucócitos humanos, atividade antimicrobiana utilizando o teste de microdiluição em caldo e determinação da capacidade antioxidante pelo método de espécies reativas ao ácido tiobarbitúrico foram os ensaios biológicos realizados. Os resultados mostraram que as quatro frações peptídicas obtidas apresentaram-se com baixo peso molecular e elevados teores proteico e mineral; quanto ao perfil aminoacídico, apresentaram elevadas e diferenciadas quantidades de ácido glutâmico e serina, que pouco variaram de acordo com o processo de obtenção; não se mostraram tóxicos para leucócitos humanos; demonstraram atividade antimicrobiana para Escherichia coli e Salmonella Enteritidis e elevada capacidade antioxidante. Os resultados físico-químicos das frações de caseinofosfopeptídeos demonstraram elevada composição nutricional em termos de proteína e, principalmente, cálcio. O conjunto de dados indicou que alterações no tempo e na temperatura de reação para a obtenção dos hidrolisados não interferem nas suas qualidades biológicas, mostrando serem seguros para a promoção da saúde e para a aplicação em situações especiais, que envolvem pacientes desnutridos, imunossuprimidos, com comprometimento ósseo ou gastrintestinal decorrentes de inflamações e infecções.

Several methods have been employed for the production of bioactive peptides for health promotion. The aim of this study was to produce and characterize Casein phosphopeptides obtained by sodium caseinate tryptic hydrolysis under different temperatures (37 and 50 °C) and reaction times (2 and 4 h), and evaluate their biological capabilities. They have been characterized by assessing their centesimal composition, by polyacrylamide gel electrophoresis, Mass Spectrometry, and High-Performance Liquid Chromatography. The biological activities tested included toxicity for human leukocytes, antimicrobial assay using the microdilution test, and determination of the antioxidant capacity by the thiobarbituric acid reactive species method. The results showed that the four fractions obtained were of low molecular weight with high protein and mineral contents; their amino acid profile showed high and differentiated amounts of glutamic acid and serine independent of the methodological procedures. The results also showed no toxicity for human peripheral leukocytes, demonstrated antimicrobial activity against Escherichia coli and Salmonella Enteritidis as well as high antioxidant capacity. The results of the physicochemical Casein phosphopeptides' fractions showed high nutritional composition in terms of protein and, particularly, calcium. The biological assays indicated that time and temperature changes in the process for obtaining casein hydrolysates have not interfered with their biological qualities. In addition, they have proven safe in promoting health in special conditions involving malnourished and/or, immunocompromised patients or those with bone and/or gastrointestinal impairment due to inflammations and infections.

In vivo postprandial bioavailability of interesterified-lipids in sodium-caseinate or chitosan based O/W emulsions.

Recent studies have shown that it should be possible to control lipid bioavailability through food structural approaches. Nevertheless, the gastrointestinal-tract physiological conditions must also be considered. To get a better understanding of this phenomenon, we evaluated the effect of emulsification, as well as the use of sodium caseinate or chitosan, on the postprandial bioavailability of interesterified-lipids in O/W emulsions after oral gastric feeding Sprague-Dawley rats. We verified that emulsification may increase lipid absorption, as determined after feeding sodium-caseinate emulsions. However, this result could not be generalised. Interesterified-lipids that were emulsified with chitosan were equally absorbed as those contained in non-emulsified interesterified-lipids/distilled-water blends.

Mechanical and permeability properties of milk protein films

Edible films present a potential alternative for replacing plastic films used for packaging in food industry. One of the major advantages is the environmental appeal of this technology, which produces no packaging waste. Some films made with other edible materials have found commercial applications, and many more are being developed using a myriad of food based components. This paper focuses on some important characteristics of films produced with sodium and calcium caseinates. The effects of caseinate type and concentration, plasticizer concentration and pH were studied. Major parameters investigated were solubility, tensile properties, water vapour and oxygen permeabilities. Caseinate films showed high solubility at pH range 6.0-8.0 and complete insolubility at pH 3.0 and 4.0. Calcium caseinate films had a higher tensile strength and a lower percent elongation at break than sodium caseinate films. There was not significant difference in water vapour and oxygen permeabilities between sodium and calcium caseinate films.

Filmes comestíveis representam uma alternativa potencial para a substituição de filmes plásticos .empregados em embalagem de alimentos. Uma de suas maiores vantagens relaciona-se com o problema de poluição ambiental por não gerar material residual. Filmes elaborados com outros materiais comestíveis não protéicos têm encontrado aplicação comercial e muitos outros ainda estão sendo pesquisados, usando uma grande variedade de componentes alimentares. Este trabalho estuda algumas características importantes dos filmes produzidos com caseinatos de sódio e de cálcio. Os efeitos do tipo e concentração de caseinato, concentração de plastificante e do pH são investigados. Os parâmetros pesquisados foram a solubilidade, propriedades de tração e permeabilidade a vapor de água e oxigênio. Filmes de caseinato apresentaram alta solubilidade na faixa de pH entre 6.0 e 8.0 e completa insolubilidade em pH 3.0 e 4.0. Maior resistência à tração e menor percentagem de alongamento no ponto de ruptura foram observados para os filmes de caseinato de cálcio, comparados aos de caseinato de sódio. Não houve diferença significativa entre os filmes de caseinato de sódio e de cálcio, no que se refere à permeabilidade a vapor de água e oxigênio.

Efeito do caseinato de sódio nas propriedades sensoriais do presunto "cook-in"

The effect of different concentrations of sodium caseinate in the sensory properties of "cook-in" ham was studied. In each of four replications, twenty ''cook-in" hams were randomly designed to one of five treatment groups in which the curing brine formulation was pumped 20% of their respectivo weights for all treatments. The basic brine composition was 0.5% phosphate; 2.0% salt; 0.4% curing salts; 0.66% ham condiment and 0.25% ascorbate, the processing conditions were the same for all treatments, but there was used different concentrations of sodium caseinate. (0.0%; 0.5%; 1.0% and 1.5%). Samples were removed for pH analysis. Tumbling losses, cooking losses and yield were calculated. Sensory properties of processed "cook-in'' hams were evaluated. The pH haven't a significative effect, because the brine was adjusted to pH 9,0 for all treatments. The hams treated with 1.0% sodium caseinate showed the greatest overall acceptability and the greatest cooking losses too. The hams treated with 0.5% sodim caseinate showed the less cooking losses and reasonable overall acceptability.

Realizou-se o estudo do efeito das diferentes concentrações de caseinato de sódio nos atributos sensoriais do presento "cook-in". Em cada uma das quatro repetições, vinte presuntos foram designados ao acaso num dos cinco tratamentos, nos quais a formulação da salmoura de cura foi injetada a 20% em relação ao peso da carne em todos os tratamentos. A composição básica da salmoura correspondeu a 0,5% fosfato; 2,0% sal; 0,4% sais de cura; 0,66% condimento para presunto e 0,25% ascorbato, as condições de processamento foram as mesmas para todos os tratamentos, mas foram utilizados diferentes concentrações de caseinato de sódio em cada tratamento (0,0%; 0,5%; 1,0% e 1,5%). Foram retiradas amostras para medir o pH. Calculou-se as perdas no tambleamento e no cozimento e o rendimento. As propriedades sensoriais do presunto "cook-in" também foram avaliadas quanto a cor, aroma, coesividade, fatiamento, sabor e textura. O pH não apresentou efeito significativo, devido à salmoura ter sido ajustada para pH 9,0 para todos os tratamentos. Os presuntos com 1,0% caseinato de sódio apresentaram uma ótima aceitabilidade, mas apresentaram também a maior perda no cozimento. Os presuntos com 0,5% de caseinato de sódio apresentaram a menor perda no cozimento e uma razoável aceitabilidade das propriedades sensoriais.

Efeito do caseinato de sódio nas propriedades sensoriais do presunto "cook-in"

The effect of different concentrations of sodium caseinate in the sensory properties of "cook-in" ham was studied. In each of four replications, twenty ''cook-in" hams were randomly designed to one of five treatment groups in which the curing brine formulation was pumped 20% of their respectivo weights for all treatments. The basic brine composition was 0.5% phosphate; 2.0% salt; 0.4% curing salts; 0.66% ham condiment and 0.25% ascorbate, the processing conditions were the same for all treatments, but there was used different concentrations of sodium caseinate. (0.0%; 0.5%; 1.0% and 1.5%). Samples were removed for pH analysis. Tumbling losses, cooking losses and yield were calculated. Sensory properties of processed "cook-in'' hams were evaluated. The pH haven't a significative effect, because the brine was adjusted to pH 9,0 for all treatments. The hams treated with 1.0% sodium caseinate showed the greatest overall acceptability and the greatest cooking losses too. The hams treated with 0.5% sodim caseinate showed the less cooking losses and reasonable overall acceptability.

Realizou-se o estudo do efeito das diferentes concentrações de caseinato de sódio nos atributos sensoriais do presento "cook-in". Em cada uma das quatro repetições, vinte presuntos foram designados ao acaso num dos cinco tratamentos, nos quais a formulação da salmoura de cura foi injetada a 20% em relação ao peso da carne em todos os tratamentos. A composição básica da salmoura correspondeu a 0,5% fosfato; 2,0% sal; 0,4% sais de cura; 0,66% condimento para presunto e 0,25% ascorbato, as condições de processamento foram as mesmas para todos os tratamentos, mas foram utilizados diferentes concentrações de caseinato de sódio em cada tratamento (0,0%; 0,5%; 1,0% e 1,5%). Foram retiradas amostras para medir o pH. Calculou-se as perdas no tambleamento e no cozimento e o rendimento. As propriedades sensoriais do presunto "cook-in" também foram avaliadas quanto a cor, aroma, coesividade, fatiamento, sabor e textura. O pH não apresentou efeito significativo, devido à salmoura ter sido ajustada para pH 9,0 para todos os tratamentos. Os presuntos com 1,0% caseinato de sódio apresentaram uma ótima aceitabilidade, mas apresentaram também a maior perda no cozimento. Os presuntos com 0,5% de caseinato de sódio apresentaram a menor perda no cozimento e uma razoável aceitabilidade das propriedades sensoriais.

Efeito do caseinato de sódio nas propriedades sensoriais do presunto "cook-in" / Effect of sodium caseinate in the sensory properties of "cook-in" ham

Realizou-se o estudo do efeito das diferentes concentrações de caseinato de sódio nos atributos sensoriais do presento "cook-in". Em cada uma das quatro repetições, vinte presuntos foram designados ao acaso num dos cinco tratamentos, nos quais a formulação da salmoura de cura foi injetada a 20 por cento em relação ao peso da carne em todos os tratamentos. A composição básica da salmoura correspondeu a 0,5 por cento fosfato; 2,0 por cento sal; 0,4 por cento sais de cura; 0,66 por cento condimento para presunto e 0,25 por cento ascorbato, as condições de processamento foram as mesmas para todos os tratamentos, mas foram utilizados diferentes concentrações de caseinato de sódio em cada tratamento (0,0 por cento; 0,5 por cento; 1,0 por cento e 1,5 por cento). Foram retiradas amostras para medir o pH. Calculou-se as perdas no tambleamento e no cozimento e o rendimento. As propriedades sensoriais do presunto "cook-in" também foram avaliadas quanto a cor, aroma, coesividade, fatiamento, sabor e textura. O pH não apresentou efeito significativo, devido à salmoura ter sido ajustada para pH 9,0 para todos os tratamentos. Os presuntos com 1,0 por cento caseinato de sódio apresentaram uma ótima aceitabilidade, mas apresentaram também a maior perda no cozimento. Os presuntos com 0,5 por cento de caseinato de sódio apresentaram a menor perda no cozimento e uma razoável aceitabilidade das propriedades sensoriais.

The effect of different concentrations of sodium caseinate in the sensory properties of "cook-in" ham was studied. In each of four replications, twenty ''cook-in" hams were randomly designed to one of five treatment groups in which the curing brine formulation was pumped 20 percent of their respectivo weights for all treatments. The basic brine composition was 0.5 percent phosphate; 2.0 percent salt; 0.4 percent curing salts; 0.66 percent ham condiment and 0.25 percent ascorbate, the processing conditions were the same for all treatments, but there was used different concentrations of sodium caseinate. (0.0 percent; 0.5 percent; 1.0 percent and 1.5 percent). Samples were removed for pH analysis. Tumbling losses, cooking losses and yield were calculated. Sensory properties of processed "cook-in'' hams were evaluated. The pH haven't a significative effect, because the brine was adjusted to pH 9,0 for all treatments. The hams treated with 1.0 percent sodium caseinate showed the greatest overall acceptability and the greatest cooking losses too. The hams treated with 0.5 percent sodim caseinate showed the less cooking losses and reasonable overall acceptability.