Spray Drying of Xoconostle Juice: Interaction of Microstructure, Function, and Drying Operation Conditions

The xoconostle fruit (Opuntia matudae) is rich in polysaccharides, soluble fiber, simple phenols, betalains, and ascorbic acid. However, its consumption is limited due to its high acidity. Spray drying could be a technological option to strengthen the sustainability of xoconostle giving a re-valorization as a possible natural additive for the food industry. The food powders have to be designed considering aspects related to the effect of processing conditions on final quality properties; in this case, the effect of different drying air temperatures was evaluated on moisture content, water activity (Aw), glass transition temperature, microstructure, antioxidant activity, phenolic, and betalain compounds. For all cases, the drying air temperature had a positive effect on physical stability, at low levels of water activity and moisture content, and glass transition temperature (Tg) was increased. The biological functionality (assessed through phenolics, betalain compounds, and antioxidant activity) was also kept constant for all processing conditions investigated. However, the most evident changes were observed at microscopic scale analyzed through morphometric parameters

Morphological and Physicochemical Characterization of Agglomerates of Titanium Dioxide Nanoparticles in Cell Culture Media

Titanium dioxide nanoparticles (TiO2 NP) are possible carcinogenic materials (2B-IARC) and their toxicity depends on shape, size, and electrical charge of primary NP and on the system formed by NP media. The aim of this work was to characterize agglomerates of three TiO2 NP by evaluating their morphometry, stability, and zeta potential (ζ) in liquid media and their changes with time. Sizes of agglomerates by dynamic light scattering (DLS) resulted to be 10–50 times larger than those obtained by digital image analysis (DIA) given the charged zone around particles. Fractal dimension (FD) was highest for agglomerates of spheres and belts in F12K, and in E171 in FBS media. E171 and belts increased FD with time. At time zero, using water as dispersant FD was larger for agglomerates of spheres than for of E171. Belts suspended in water had the smallest values of circularity (Ci) which was approximately unchanged with time. All dispersions had ζ values around −30 mV at physiological pH (7.4) and dispersions of NP in water and FBS showed maximum stability (Turbiscan Lab analysis). Results help in understanding the complex NP geometry-size-stability relationships when performing in vivo and in vitro environmental-toxicity works and help in supporting decisions on the usage of TiO2 NP

Películas y recubrimientos comestibles funcionalizados

Pests and inadequate post-harvest handling has led to losses in horticultural products, therefore the development and production of edible biodegradable films has been sought as an alternative in recent years. These edible films are made with materials such as carbohydrates, proteins, or lipids, with physical and mechanical characteristics similar to the non-degradable packaging, but with the advantage of having a bioactive function as barriers; by adding vegetable extracts, edible biodegradable films may exert antimicrobial activity, protection against UV and visible light, against carriers of antioxidants and/or dyes, along with improving the visual characteristics of the product. Because of these attributes, edible biodegradable films have been referred to as “Intelligent films”, since considerable progress has been observed in their elaboration, such as the presence of colorful sensors capable of detecting chemical changes and the presence of microorganisms in foods, revealing the state in which they are optimal and even if they are or not in an adequate state for consumption. The objective of this work is to make a summary of various research and current trends in the study and development of edible films and coatings, emphasizing their application in the horticultural chain and their effect on fresh and minimally processed foods.Debido a las pérdidas en productos hortofrutícolas por plagas y manejo postcosecha inadecuado, en los últimos años se ha buscado el desarrollo y la producción de películas comestibles biodegradables como una forma de protección. Estas películas comestibles están hechas con materiales como carbohidratos, proteínas o lípidos, con características físicas y mecánicas similares a los envases no degradables, pero con la ventaja de funcionar como barreras bioactivas, ya que, mediante la adición de extractos vegetales, pueden presentar actividad antimicrobiana, protección contra la luz UV y visible, servir como acarreadores de antioxidantes y/o colorantes, mejorando con esto las características visuales del producto. Debido a estos atributos, han sido denominadas "películas inteligentes", ya que se ha observado un progreso considerable en su elaboración, como la presencia de sensores coloridos capaces de detectar cambios químicos y la presencia de microorganismos en los alimentos, mostrando si son o no, óptimos para el consumo. El objetivo de este trabajo es hacer una síntesis de diversas investigaciones, así como las tendencias recientes en el estudio y desarrollo de películas y recubrimientos comestibles, con énfasis en su aplicación a la cadena hortofrutícola y su efecto sobre productos frescos y mínimamente procesados

Effect of traditional dehydration processing of pepper jalapeno rayado (Capsicum annuum) on secondary metabolites with antioxidant activity

Jalapeno rayado peppers (Capsicum annuum) are usually subjected to a traditional smoke-dehydration process using Quercus sp. This treatment provides peppers with their characteristic functional attributes. To differentiate the production of antioxidant metabolites during the dehydration-smoking process, this process was compared with convective dehydration, both at 60°C. A higher antioxidant activity in smoke-dried pepper was observed due to the increase in concentration of phenolic compounds, flavonoids and Maillard products in the last hours of the process and was related to the presence of radicals with m/z (-) values: 585.32, 292.2, 326.18, 653.28, 240.11 and 210.14, generated during both dehydration processes. The change in colour was mainly due to the increase of Maillard compounds. Convective dehydration favoured the extraction of capsaicinoids, whereas no significant change was observed in smoke-dehydration, and carotenoid degradation was 40% with either process. A similar final moisture content was achieved in both processes

Physical and functional properties of roselle (Hibiscus sabdariffa L.) extract spray dried with maltodextrin-gum arabic mixtures

Hibiscus sabdariffa L. calyces are a source of phenolic compounds which provide high antioxidant activity. The aim of this work was to improve the stability of roselle extracts by spray-drying using combinations of maltodextrin (MD) and gum arabic (GA) as carrier agents, preserving the antioxidant compounds. MD:GA matrices resulted in a very good option to produce roselle powders with excellent physical properties: low moisture content (99%). The powders showed low cohesiveness and a very good flowability. Higher GA in the matrix improved the retention of anthocyanins (171.21 ± 0.13 mg cyn-3-glu/100 g d.m.), polyphenols (465.80 ± 0.13 mg GAE/100 g d.m.) and the antioxidant capacity (95.5 ± 0.82 mmol Trolox/kg d.m.). These powders could be applied as an instant “agua de jamaica” product, giving an easy preparation method for the consumer. The antioxidant capacity of the reconstituted roselle powders was similar to those of mango and pineapple freshly squeezed juices, suggesting that this beverage could provide a relevant functional input. Practical applications: Mexico is one of the largest consumers among Latin American countries of a refreshing infusion called “agua de jamaica” made from Hibiscus sabdariffa. The main drawback of this beverage lies in its short shelf life. In this work, we showed that spray-drying proved to be an adequate process for obtaining an alternative product that presents higher stability while retaining the functional characteristics of the original drink.Fil: Archaina, Diego Alberto. Universidad Nacional de Entre Ríos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Vasile, Franco Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; Argentina. Universidad Nacional del Chaco Austral; ArgentinaFil: Jiménez-Guzmán, Jaime. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Alamilla-Beltrán, Liliana. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Schebor, Carolina Claudia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Químicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Químicos; Argentin

Microencapsulation of Lipases Produced by Dripping and Jet Break-Up for Biodiesel Production

A high-performance and scalable lipase immobilization method using a dipping and jet break-up technique was reported for the production of microcapsule biocatalysts with an entrapped cascade of lipase enzyme. The lipase from Candida antarctica (CALb) recombinant Aspergillus oryzae and from the vegetal of Jatropha curcas L. (var. Sevangel) in Morelos State of Mexico were entrapped by mixing with a sodium alginate biopolymer at different concentrations. The obtained microcapsules were hardened in a CaCl2 solution, aiming at developing Ca2+ alginate microbeads with sizes mostly from 220 to 300 μm. The relationship between the process variables with the shape and size of the alginate drops before and after the gelation was established with aid of optical image analysis. The results showed that a critical Ohnesorge number (Oh) > 0.24 was required to form spherical microencapsulated beads. The biodiesel production via esterification/transesterification reaction was performed using the crude Jatropha curcas L. oil as feedstock in a batch reactor using lipase microcapsules as biocatalysts. Under the optimal reaction condition (ethanol-to-oil mass ratio: 10; water content 9.1 wt%, microencapsulated biocatalyst mass: 5.25 g, reaction temperature: 35 °C, pH of reaction mixture 7.5, stirring force 6 g), an approximately 95% fatty acid ethyl esters (FAEE) yield could be obtained. The biodiesel obtained from this work completely satisfied with the related ASTM D6751 and EN14214 standards. The microencapsulation technique reported herein allows the production of lipase microcapsules on a continuous large scale with the characteristics required for sustainable biofuel production and it can be also applied in other fields such as food processing and the pharmaceutical industry

Prosopis alba exudate gum as new carrier agent for obtaining powdered Hibiscus sabdariffa aqueous extracts by spray drying

The objective of this work was to study the functional behavior of Prosopis alba exudate gum (G) as component of powders rich in antioxidant pigments. For this purpose, the morphological, structural and chromatic characteristics as well as physical, biological and stability properties of spray dried aqueous extracts of Hibiscus sabdariffa were evaluated for different ratios of maltodextrin and G, and opportunely compared with gum arabic (GA). Powders containing G showed low moisture (4.9% ds.), low water activity (aw 95%) and small (∼25 μm) spherical-shaped particles, with a glass transition temperature (Tg = 52 °C), similar to those containing GA. Phenolic compounds, naturally present in G, improved the storage stability of Hibiscus extract pigments contributing to the preservation of the antioxidant properties. Results encourage to consider Prosopis alba exudate gum as a promising alternative to gum arabic, with the subsequent benefits stemmed from adding value to an underutilized resource.Fil: Vasile, Franco Emanuel. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; ArgentinaFil: Archaina, Diego Alberto. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Santa Fe. Instituto de Ciencia y Tecnologia de Los Alimentos de Entre Rios. - Universidad Nacional de Entre Rios. Instituto de Ciencia y Tecnologia de Los Alimentos de Entre Rios.; ArgentinaFil: Jiménez Guzmán, Jaime. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Gutiérrez López, Gustavo Fidel. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Alamilla Beltrán, Liliana. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Mazzobre, Maria Florencia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Quimicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Quimicos.; Argentin

Parámetros de calidad y caracterización morfométrica de palomitas de maíz de aire caliente en relación con el contenido de humedad

12 páginasUpon popping, corn kernels undergo substantial dehydration. Initial moisture content of the kernel, popping method and temperature determine the final quality, and physical characteristics of the flakes. In this work, corn kernels (Zea Mays var Everta) at different moisture contents were subjected to hot-air popping and quality, physical and morphometric parameters of the flakes were evaluated, and related with their microstructural features. The best moisture content for hot-air popping was 9.14%. Macro and microstructural examination and digital image analysis of the flakes showed that, at the macro level, the roughness of the different flakes, as given by their fractal dimension (FD), were similar among morphologies, whereas at the microscale, it was possible to differentiate between them. Additionally, at the macro-scale, for the different morphologies high correlations were found between areas and the linear dimensions (Feret or width)FD of evaluated flakes. Moreover, when using the FD of the microstructures as the exponent, high correlations were also observed, which confirms an analog multiscale behavior between the roughness of the flakes and their microstructures.Al reventar, los granos de maíz se deshidratan sustancialmente. El contenido de humedad inicial del grano, el método de estallido y la temperatura determinan la calidad final y las características físicas de las hojuelas. En este trabajo, granos de maíz (Zea Mays var Everta) con diferentes contenidos de humedad fueron sometidos a soplado con aire caliente y se evaluaron parámetros físicos, morfométricos y de calidad de las hojuelas, y se relacionaron con sus características microestructurales. El mejor contenido de humedad para hacer estallar con aire caliente fue 9.14%. El examen macro y microestructural y el análisis de imágenes digitales de las lascas mostraron que, a nivel macro, la rugosidad de las diferentes lascas, dada por su dimensión fractal (FD), era similar entre morfologías, mientras que a microescala era posible diferenciar entre ellos. Además, a macroescala, para las diferentes morfologías se encontraron altas correlaciones entre las áreas y las dimensiones lineales (Feret o ancho)FD de las lascas evaluadas. Además, al utilizar la FD de las microestructuras como exponente, también se observaron altas correlaciones, lo que confirma un comportamiento multiescala analógico entre la rugosidad de las lascas y sus microestructuras

Thermal transitions and enthalpic relaxations as related to the stability of microencapsulated paprika powders

Present work investigates the effect of thermal transitions and enthalpy relaxation phenomenon on the physico-chemical stability of paprika microencapsulated powders. Wall materials were combinations of soy protein isolates, maltodextrin and gum arabic. Powders stability was evaluated through the solid-water interactions, determined by sorption kinetics, calorimetry and color changes. The water sorption isotherms were well described by the GAB model. Below the critical condition, aw 0.6 and water content 11% (d. b.) the systems were in amorphous state at 25 °C, and enthalpy relaxations were detectable as endothermal events in the stored samples. The magnitude of the enthalpy relaxations increased with storage temperature below Tg and with time of storage. In the amorphous microencapsulates, luminosity changes measured as (Lo*-L*) values decreased as a function of time and aw, indicating pigment decoloration. The kinetics of the enthalpy relaxations changes, instead of the punctual values of the variables under study, were related to the dynamics of deteriorative changes. It can be concluded that enthalpy relaxation phenomenon can be established as a criterion for defining storage conditions or predict changes in microencapsulated and other systems that have to be stored in the glassy state.Fil: Porras Saavedra, Josefina. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Favre, Leonardo Cristian. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Químicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Químicos; ArgentinaFil: Alamilla Beltrán, Liliana. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Mazzobre, Maria Florencia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Químicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Químicos; ArgentinaFil: Gutiérrez López, Gustavo Fidel. INSTITUTO POLITÉCNICO NACIONAL (IPN);Fil: Buera, Maria del Pilar. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Industrias. Instituto de Tecnología de Alimentos y Procesos Químicos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Tecnología de Alimentos y Procesos Químicos; Argentin

Synthesis, Controlled Release, and Stability on Storage of Chitosan-Thyme Essential Oil Nanocapsules for Food Applications

The nanoencapsulation of thyme essential oil has been greatly important in food science, given its remarkable antioxidant and antimicrobial capacity. However, its analysis in storage has not been established in terms of physical stability, antioxidant capacity, and release studies. In this paper, chitosan-thyme oil nanocapsules were prepared by the ionic gelation method. These were characterized for differential calorimetry, release kinetic, and infrared spectroscopy. The chitosan-thyme oil nanocapsules were stored at 4 and 25 °C for 5 weeks, the changes in particle size, zeta potential, stability (diffuse reflectance), and antioxidant capacity were analyzed and associated with nanocapsules’ functionality. The results show that the storage time and temperature significantly modify the particle size (keeping the nano-size throughout the storage), the release of the bioactive was Fickian with t0.193 according to Korsmery & Peppas and best described by Higuchi model associated with changes in the zeta potential from 8 mV to −11 mV at 4 °C. The differential scanning calorimetry and infrared spectroscopy results confirm the good integration of the components. The antioxidant capacity revealed a direct relationship with residual oil concentration with a decrease in the ABTS test of 15% at 4 °C and 37% at 25 °C. The residual bioactive content was 77% at 4 °C and 62% at 25 °C, confirming nanoencapsulation effectiveness. The present investigation provides helpful information so that these systems can be applied in food conservation