RESUMO

The rising consumer demand for safer, healthier, and fresher-like food has led to the emergence of new concepts in food packaging. In addition, the growing concern about environmental issues has increased the search for materials derived from non-petroleum sources and biodegradable options. Thus, active films based on biopolymers loaded with natural active compounds have great potential to be used as food packaging. However, several lipophilic active compounds are difficult to incorporate into aqueous film-forming solutions based on polysaccharides or proteins, and the hydrophilic active compounds require protection against oxidation. One way to incorporate these active compounds into film matrices is to encapsulate them in emulsions, such as microemulsions, nanoemulsions, Pickering emulsions, or double emulsions. However, emulsion characteristics can influence the properties of active films, such as mechanical, barrier, and optical properties. This review addresses the advantages of using emulsions to encapsulate active compounds before their incorporation into biopolymeric matrices, the main characteristics of these emulsions (emulsion type, droplet size, and emulsifier nature), and their influence on active film properties. Furthermore, we review the recent applications of the emulsion-charged active films in food systems.

RESUMO

La leptospirosis es considerada una zoonosis bacteriana de importancia en salud pública. Es común en áreas tropicales, especialmente en países en desarrollo con escasos recursos de salud y saneamiento. Este estudio evaluó la presencia de Leptospira spp. en bovinos sacrificados en un matadero de la región Centro-Oeste de São Paulo, Brasil, así como animales positivos identificados tanto en serología como por análisis molecular. Se investigaron muestras biológicas de sangre, hígado y riñones de 150 bovinos mediante la técnica de Prueba de Aglutinación Microscópica (MAT) y Reacción en Cadena de la Polimerasa convencional (cPCR). Los resultados serológicos mostraron que de los 150 animales, 71 (47,3%) fueron reactivos. Los resultados moleculares mostraron la presencia de Leptospira spp. en riñones de 21 (14%) animales, en hígado de cinco (3,3%) animales, en hígado y riñones en dos animales (1,3%) y en sangre, en un (0,7%) animal. Estos resultados indican una alerta sobre la salud de los bovinos de carne debido a la posibilidad de que estos animales sean fuente de infección y la importancia de la característica ocupacional de esta enfermedad. También se verificó la importancia de complementar las técnicas serológicas y moleculares.  

Leptospirosis is considered a bacterial zoonosis of public health importance. It is common in tropical areas, especially in developing countries with scarce health and sanitation resources. This study evaluated the presence of Leptospira spp. in slaughtered bovine in a slaughterhouse in the Midwest region of São Paulo, Brazil, as well as identified positive animals both in serology and by molecular analysis. Biological samples of blood, liver and kidneys from 150 cattle were investigated by the technique of Microscopic Agglutination Test (MAT) and conventional Polymerase Chain Reaction (cPCR). The serological results showed that of the 150 animals, 71 (47.3%) were reactive. The molecular results showed the presence of Leptospira spp. in kidneys of 21 (14%) animals, in liver of five (3.3%) animals, in liver and kidneys in two animals (1.3%) and in blood, in one (0.7%) animal. These results indicate a warning about the health of beef cattle due to the possibility of these animals being the source of infection and the importance of the occupational characteristic of this disease. It was also verified the importance of complementing serological and molecular techniques.

A leptospirose é considerada uma zoonose bacteriana de importância para a saúde pública. É comum em áreas tropicais, especialmente em países em desenvolvimento com escassos recursos de saúde e saneamento. Este estudo avaliou a presença de Leptospira spp. em bovinos abatidos em frigorífico da região Centro-Oeste de São Paulo, Brasil, e identificou animais positivos tanto por sorologia quanto em análise molecular. Amostras biológicas de sangue, fígado e rins de 150 bovinos foram investigadas pela técnica de Teste de Aglutinação Microscópica (MAT) e Reação em Cadeia da Polimerase convencional (cPCR). Os resultados sorológicos mostraram que dos 150 animais, 71 (47,3%) foram reativos. Os resultados moleculares mostraram a presença de Leptospira spp. nos rins de 21 animais (14%), no fígado de 5 animais (3,3%), no fígado e rins em 2 animais (1,3%) e no sangue em 1 animal (0,7%). Esses resultados indicam um alerta sobre a saúde dos bovinos de corte devido à possibilidade desses animais serem fonte de infecção e a importância da característica ocupacional desta doença. Verificou-se também a importância de complementar as técnicas sorológicas e moleculares.

RESUMO

A leptospirose é considerada uma zoonose bacteriana de importância para a saúde pública. É comum em áreas tropicais, especialmente em países em desenvolvimento com escassos recursos de saúde e saneamento. Este estudo avaliou a presença de Leptospira spp. em bovinos abatidos em frigorífico da região Centro-Oeste de São Paulo, Brasil, e identificou animais positivos tanto por sorologia quanto em análise molecular. Amostras biológicas de sangue, fígado e rins de 150 bovinos foram investigadas pela técnica de Soroaglutinação Microscópica (SAM) e Reação em Cadeia da Polimerase convencional (cPCR). Os resultados sorológicos mostraram que dos 150 animais, 71 (47,3%) foram reagentes. Os resultados moleculares mostraram a presença de Leptospira spp. nos rins de 21 animais (14%), no fígado de 5 animais (3,3%), no fígado e rins em 2 animais (1,3%) e no sangue em 1 animal (0,7%). Esses resultados indicam um alerta sobre a saúde dos bovinos de corte devido à possibilidade desses animais serem fonte de infecção e a importância da característica ocupacional desta doença. Verificou-se também a importância de complementar as técnicas sorológicas e moleculares.

Leptospirosis is considered a bacterial zoonosis of public health importance. It is common in tropical areas, especially in developing countries with scarce health and sanitation resources. This study evaluated the presence of Leptospira spp. in slaughtered bovine in a slaughterhouse in the Midwest region of São Paulo, Brazil, as well as identified positive animals both in serology and by molecular analysis. Biological samples of blood, liver and kidneys from 150 cattle were investigated by the technique of Microscopic Agglutination Test (MAT) and conventional Polymerase Chain Reaction (cPCR). The serological results showed that of the 150 animals, 71 (47.3%) were reactive. The molecular results showed the presence of Leptospira spp. in kidneys of 21 (14%) animals, in liver of five (3.3%) animals, in liver and kidneys in two animals (1.3%) and in blood, in one (0.7%) animal. These results indicate a warning about the health of beef cattle due to the possibility of these animals being the source of infection and the importance of the occupational characteristic of this disease. It was also verified the importance of complementing serological and molecular techniques.

La leptospirosis es considerada una zoonosis bacteriana de importancia en salud pública. Es común en áreas tropicales, especialmente en países en desarrollo con escasos recursos de salud y saneamiento. Este estudio evaluó la presencia de Leptospira spp. en bovinos sacrificados en un matadero de región Centro-Oeste de São Paulo, Brasil, así como animales positivos identificados tanto en serología como por análisis molecular. Se investigaron muestras biológicas de sangre, hígado y riñones de 150 bovinos mediante la técnica de Aglutinación Microscópica (MAT) y Reacción en Cadena de la Polimerasa convencional (cPCR). Los resultados serológicos mostraron que de los 150 animales, 71 (47,3%) fueron reactivos. Los resultados moleculares mostraron la presencia de Leptospira spp. en riñones de 21 (14%) animales, en hígado de cinco (3,3%) animales, en hígado y riñones en dos animales (1,3%) y en sangre, en un (0,7%) animal. Estos resultados indican una alerta sobre la salud de los bovinos de carne debido a la posibilidad de que estos animales sean fuente de infección y la importancia de la característica ocupacional de esta enfermedad. También se verificó la importancia de complementar las técnicas serológicas y moleculares.

Assuntos

RESUMO

This study investigated the impact of adding ß-carotene on the structure of fresh O/W emulsions with different oil phase (sunflower oil-LCT or NEOBEE®1053-MCT) and emulsifiers (WPI, Tween 80 - T80 or WPI/T80 mixture). In this sense, the behavior of emulsions through the gastrointestinal tract, the stability and bioaccessibility of ß-carotene were also assessed. The ß-carotene reduced the interfacial tension of the LCT/MCT-water systems. The addition of ß-carotene promoted an increase of viscoelasticity of LCT/MCT-T80 (0.5%WPI/0.5%T80 and 1%T80 w/w) interfaces, but an increase of WPI content reduced the viscoelasticity of interfacial layers (LCT/MCT-1% WPI). These changes in the interface properties influenced the mean droplet size and ζ-potential of the fresh emulsions. LCT systems presented similar bioaccessibility/stability of ß-carotene. However, ß-carotene entrapped within protein-coated MCT droplets was more stable than within T80-MCT systems. Our results show that ß-carotene interacted with other ingredients of emulsions changing their properties and behavior under gastrointestinal tract as well as the stability/bioaccessibility of ß-carotene.

Assuntos

RESUMO

The development of plant protein-based delivery systems to protect and control lipophilic bioactive compound delivery (such as vitamins, polyphenols, carotenoids, polyunsaturated fatty acids) has increased interest in food, nutraceutical, and pharmaceutical fields. The quite significant ascension of plant proteins from legumes, oil/edible seeds, nuts, tuber, and cereals is motivated by their eco-friendly, sustainable, and healthy profile compared with other sources. However, many challenges need to be overcome before their widespread use as raw material for carriers. Thus, modification approaches have been used to improve their techno-functionality and address their limitations, aiming to produce a new generation of plant-based carriers (hydrogels, emulsions, self-assembled structures, films). This paper addresses the advantages and challenges of using plant proteins and the effects of modification methods on their nutritional quality, bioactivity, and techno-functionalities. Furthermore, we review the recent progress in designing plant protein-based delivery systems, their main applications as carriers for lipophilic bioactive compounds, and the contribution of protein-bioactive compound interactions to the dynamics and structure of delivery systems. Expressive advances have been made in the plant protein area; however, new extraction/purification technologies and protein sources need to be found Their functional properties must also be deeply studied for the rational development of effective delivery platforms.

Assuntos

RESUMO

The engineering of ingredients emerges as a strategy to design emulsified products aiming to control the lipid hydrolysis. In this context, oil-in-water (O/W) emulsions composed of different oil phases (Sunflower oil - LCT or NEOBEE® 1053 - MCT) and stabilized by whey protein isolate - WPI (1% w/w), Tween 80 - T80 (1% w/w) or varied ratios of WPI/T80 (0.9975%WPI/0.0025%T80; 0.75%WPI/0.25%T80; 0.5%WPI/0.5%T80 w/w) were produced and submitted to simulated gastrointestinal conditions. The lipolysis of LCT was influenced by the fatty acid chain length and emulsifier composition, while only the fatty acid chain length affected the lipolysis of MCT. The emulsions produced with LCT and 1%WPI or 09975%WPI/00025%T80 showed the highest release rate of free fatty acids (FFAs), but similar result was observed for the 0.5%WPI/0.5%T80 system. In the 0.5%WPI/0.5%T80 mixture, WPI and T80 worked together and achieved an improved performance during the gastric (stability similar as 1%T80 emulsion) and small intestinal phases (lipolysis similar as 1%WPI emulsion). The rational selection of ingredients is useful to design emulsions with improved performance as a delivery system since the emulsion structural stability during digestion, the oil type and interaction between lipase-interface had a marked impact on the efficiency of lipid digestion.

Assuntos

RESUMO

The aim of this study was to evaluate the effects of non-thermal and thermal high-intensity ultrasound (HIUS) treatment on the microbial and enzymatic inactivation, physicochemical properties, and kinetic stability of the raw milk by applying different energy densities (1, 3, 5, and 7 kJ/mL). Two HIUS treatments were evaluated based on different nominal powers, named HIUS-A and HIUS-B, using 100 W and 475 W, respectively. HIUS-A treatment was non-thermal processing while HIUS-B was a thermal treatment only for the energy densities of 5 and 7 kJ/mL since the final temperature was above 70 °C. The HIUS-B treatment showed to be more efficient. Log reductions up to 3.9 cycles of aerobic mesophilic heterotrophic bacteria (AMHB) were achieved. Significant reductions of the fat globule size, with diameters lower than 1 µm, better color parameters, and kinetic stability during the storage were observed. Also, HIUS-B treatment inactivated the alkaline phosphatase and lactoperoxidase. The HIUS-B treatment at 3 kJ/mL worked below 57 °C being considered a border temperature since it did not cause unwanted physicochemical effects. Furthermore, a microbial inactivation of 1.8 ± 0.1 log cycles of AMHB was observed. A proper inactivation of only the Alkaline phosphatase and a significant reduction of the fat globules sizes, which kept the milk kinetically stable during storage was achieved.

Assuntos

RESUMO

An in vitro digestibility protocol was used to elucidate the role of different emulsifying polysaccharides particles on the lipid digestion rate of oil-in-water Pickering emulsions. Emulsions stabilized by cellulose crystals (CCrys), cellulose nanofibers (CNFs), chitosan particles and a conventional emulsifier (Tween 80) were evaluated concerning microstructure, droplet size, zeta potential and free fatty acids released during digestion. After gastric step, the high positive charge of chitosan-stabilized emulsions favored the droplets disaggregation resulting in a mild effect of bridging flocculation by particles sharing and displacement of the size curve distribution toward lower size. After passing through the intestinal condition, these emulsions presented few droplets and chitosan aggregates with a monomodal size distribution and high mean droplet size (D4,3 = 197 ±â€¯8 µm). On the other hand, Tween 80, CCrys and CNFs were able to inhibit lipid digestion and no changes on mean droplet size were observed following intestinal step. CNFs-stabilized emulsion showed the lowest lipid digestion, whereas the strong adherence of the CCrys particles onto the droplet interface became them resistant to displacement by surface-active components (i.e. bile salts and lipase enzyme). On the other hand, a slow lipid hydrolysis could be observed in chitosan-stabilized emulsions promoted by competition between chitosan aggregates and intestinal fluids by the oil droplet interface. Studying the emulsions stabilized using different polysaccharides particles on gastrointestinal conditions we could elucidate important features for their potential application as control systems of lipid digestion rate, as well as, as delivery systems of lipophilic compounds.

Assuntos

RESUMO

Water-in-oil high internal phase emulsions (HIPEs) can provide interesting textures that could be used to reduce trans- and/or saturated fat content in food products. On the other hand oil-in-water emulsions can be found in a variety of food and beverages. Moreover, strategies aiming synthetic or semi-synthetic ingredients replacement by natural alternatives for food applications has been pursuit. For these purposes, the effect of partial replacement of PGPR by lecithin on properties of either W/O-HIPEs or O/W emulsions manufactured from the same initial composition but showing different volume fraction of dispersed phase were investigated aiming to understand the behaviour of emulsifiers' mixture in water-oil or oil-water interfaces. Firstly, water-in-oil HIPEs were produced using a rotor-stator device. At fixed total amount of emulsifier (2% w/w), W/O emulsions stabilized with LEC:PGPR ratios of 0.5:1.5 and 1.0:1.0 showed similar droplet size with a better kinetic stability compared to emulsions containing only PGPR. These results indicated good interaction between LEC and PGPR, which was also confirmed by dynamic interfacial tension profile and interfacial dilational rheology. In order to reduce the droplet size of W/O-HIPEs, these emulsions were subsequently subjected to high-pressure homogenization and interestingly phases inversion was observed. Confocal microscopy confirmed the phases inversion attributed to high input of energy leading to the formation of O/W emulsions. Then both W/O-HIPEs and O/W emulsions were investigated regarding LEC:PGPR mixtures as emulsifiers. All W/O-HIPEs showed shear thinning behavior and high viscosity at low shear rate whereas O/W emulsions showed low viscosity and Newtonian behavior. The increase of lecithin content in emulsifier mixture led to more stable O/W emulsions, whereas more stable W/O-HIPEs were produced by lecithin and PGPR mixtures ratio of 0.5:1.5 and 1.0:1.0.

Assuntos

RESUMO

Great efforts have been made to design emulsions considering the need to perform an effective encapsulation, protection, vehiculation, and bioaccessibility of lipophilic compounds. This task can be achieved by manipulating the structure of the emulsion based on the choice of the processes and ingredients of the aqueous phase, interface, and lipid matrix. Thus, the main focus of this perspective is to provide insights into the use of ingredient engineering in manipulating/building emulsion structures that enhance lipophilic compound release and bioaccessibility.

Assuntos

RESUMO

Cellulose nanofibers (CNFs) from banana peels was evaluated as promising stabilizer for oil-in-water emulsions. CNFs were treated using ultrasound and high-pressure homogenizer. Changes on the size, crystallinity index and zeta potential of CNFs were associated with the intense effects of cavitation phenomenon and shear forces promoted by mechanical treatments. CNFs-stabilized emulsions were produced under the same process conditions as the particles. Coalescence phenomenon was observed in the emulsions produced using high-pressure homogenizer, whereas droplets flocculation occurred in emulsions processed by ultrasound. In the latter, coalescence stability was associated with effects of cavitation forces acting on the CNFs breakup. Thus, smaller droplets created during the ultrasonication process could be recovered by particles that acted as an effective barrier against droplets coalescence. Our results improved understanding about the relationship between the choice of emulsification process and their effects on the CNFs properties influencing the potential application of CNFs as a food emulsifier.

Assuntos

RESUMO

The relationship between the composition and structure of food emulsions was evaluated from the effect of a mixture of emulsifiers Whey protein (WPI) - Tween 80 (T80) and the oil phase features, such as chain length and unsaturation degree (sunflower oil, a long chain triacylglycerol - LCT or NEOBEE® 1053, a medium chain triacylglycerol - MCT). Emulsions with LCT showed higher droplet size than MCT as a consequence of its higher viscosity. All emulsions exhibited shear thinning behavior, but the viscosity was influenced by their interface composition. An occurrence of the destabilization mechanism by creaming was observed in turbidimetric measurements, but no visual phase separation could be observed, indicating a good kinetic stability after a 7-day storage. The initial interfacial tension of the water-LCT or water-MCT oil was about 25 mN/m, but the WPI addition (1% w/w) reduced the initial interfacial tension to approximately 20 mN/m. The increase of T80 concentration led to a decrease of the interfacial tension, reaching a value around 10 mN/m in systems with pure T80. The curves of interfacial tension of systems with LCT or MCT showed differences in the decay rate of tension over time. These differences were attributed to characteristics of the oil phase (hydrophobicity, unsaturation degree, presence of impurities) and the different proportions of each emulsifier within the mixture of emulsifiers. Finally, a higher viscoelastic interface was observed in LCT emulsions, which were mainly stabilized by WPI molecules. Such molecules presented a higher resistance to the displacement due to the competitive adsorption phenomenon, since the LCT is a more hydrophobic oil. On the other hand, the interface with MCT and a higher T80 concentration was less viscoelastic due to an easier displacement of WPI from the interface and the replacement by T80. The results indicate that T80 can be used in combination with WPI to produce emulsions with good stability and lower concentration of synthetic compounds. Lastly, the interfacial layer composition is not only dependent on the WPI-T80 ratio in the bulk phase, but also on the oily phase features. These results provide a potential strategy for designing emulsified foods based on the choice of ingredients and knowledge of the interaction between them.

Assuntos