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The selection of appropriate probiotic strains is vital for their successful inclusion in foods. These strains must withstand processing to reach consumers with ≥106 CFU/g, ensuring effective probiotic function. Achieving this in commercial products is challenging due to sensitivity to temperature during processing. In this work, Lactobacillus reuteri DSM 17938 was microencapsulated by ionic gelation (with alginate or pectin) followed by polymeric coating (with whey protein concentrate or chitosan). Then, such microcapsules were incorporated into a strawberry puree, which was subsequently dehydrated at three temperatures (40 °C, 45 °C, and 50 °C) by Refractance Window®. The ultimate aim was to demonstrate the efficacy of the proposed methods from a technological point of view. Kinetic curves of the probiotic's viability showed a high cell loading (>109 CFU/g). Additionally, an average encapsulation efficiency of 91% and a particle size of roughly 200 µm were found. A decrease in the viability of the microorganism was observed as drying temperature and time increased. As a demonstration of the above, in a particular case, drying at 45 °C and 50 °C, viable cells were found up to 165 min and 90 min, respectively; meanwhile, drying at 40 °C, viable cells were reported even after 240 min. The greatest viability preservation was achieved with Refractance Window® drying at 40 °C for 240 min when microcapsules coated with whey protein concentrate were incorporated into puree; this procedure showed great potential to produce dehydrated strawberry snacks with moisture (15%), water activity (aw < 0.6), and viability (≥106 CFU/g) suitable for functional foods. The membrane-stabilizing properties of whey protein concentrate could prevent cell damage. In contrast, probiotics in chitosan-coated capsules showed reduced viability, potentially due to antimicrobial properties and the formation of cracks. These findings signify a breakthrough in the production of dehydrated snacks with the addition of probiotics, addressing challenges in preserving the viability of these probiotics during processing; thus, opening the possibility for the development of a probiotic strawberry snack.

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The effects of the use of solvents (96% ethanol and PEG 400), solute ratios: solvent (1: 4 and 1: 6 w/w), extraction temperatures (50 and 60 °C) and leaching techniques (conventional and assisted by ultrasound) on the concentration and time of extraction of bixin from Achiote (Bixa Orellana L.) were evaluated. The extraction kinetics were constructed, and their orders were determined. The experimental values were adjusted through the mathematical models of Peleg and Azuara. ANOVA was used based on a 23 design, blocking type of technology. The kinetics showed two stages of extraction: rapid and slow. The reaction orders were decimal numbers, which indicates the complexity of the extraction mechanism. The highest orders of reaction (2.97 and 2.075) were presented with extraction with ultrasound-assisted and ethanol as solvent, at 50 and 60 °C and solute solvent ratio 1: 4 and 1: 6, respectively. The concentration of Bixin was increased by approximately 30% by increasing the temperature. The Azuara model presented the highest adjustment with a standard error < 0.1. The conventional leaching with PEG-400 required the lowest activation energy (9.2 kJ / mol) and with this treatment in 66 min the highest concentration of bixin (2.74 mgBix / gExt) was obtained. It was concluded that ultrasound-assisted leaching facilitates the extraction of bixin pigment, and the use of PEG 400 solvent is useful to obtain higher yields.

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In most cases, conventional drying produces inferior quality products and requires higher drying times. A continuous pilot Refractance Window® equipment was used to dry Aloe vera gel slabs of 5 and 10 mm thick at 60, 70, 80, and 90 °C, seeking a dry product with high-quality retention. Based on five empirical models, drying kinetics, diffusion coefficient, and activation energy were analyzed. Midilli-Kuck was the best predicting model. Short drying times (55-270 min) were needed to reach 0.10 g water/g solid. In addition, the technique yielded samples with high rehydration capacity (24-29 g water/g solid); high retention of color (∆E, 3.74-4.39); relatively low losses of vitamin C (37-59%) and vitamin E (28-37%). Regardless of the condition of temperature and sample thickness, a high-quality dried Aloe vera gel could be obtained. Compared with other methods, Refractance Window® drying of Aloe vera achieved shorter drying times with higher quality retention in terms of color, vitamins C and E, and rehydration. Finally, the dried Aloe vera gel could be reconstituted to a gel close to its fresh state by rehydration.

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The food industry has increased its interest in using "consumer-friendly" and natural ingredients to produce food products. In the case of emulsifiers, one of the possibilities is to use biopolymers with emulsification capacity, such as octenyl succinic anhydride modified starch, which can be used in combination with other polysaccharides, such as chitosan and carboxymethylcellulose, in order to improve the capacity to protect bioactive compounds. In this work, multilayer nano-emulsion systems loaded with oregano essential oil were produced by high energy methods and characterized. The process optimization was carried out based on the evaluation of particle size, polydispersity index, and zeta potential. Optimal conditions were achieved for one-layer nano-emulsions resulting in particle size and zeta potential of 180 nm and -42 mV, two layers (after chitosan addition) at 226 nm and 35 mV, and three layers (after carboxymethylcellulose addition) of 265 nm and -1 mV, respectively. The encapsulation efficiency of oregano essential oil within nano-emulsions was 97.1%. Stability was evaluated up to 21 days at 4 and 20 °C. The three layers nano-emulsion demonstrated to be an efficient delivery system of oregano essential oil, making 40% of the initial oregano essential oil available versus 13% obtained for oregano essential oil in oil, after exposure to simulated digestive conditions.

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Colombian mango production, which exceeded 261,000 t in 2020, generates about 40% of the whole fruit as solid waste, of which more than 50% are seed kernels (over 52,000 t solid by-product); though none is currently used for commercial purposes. This study reports the results of the supercritical carbon dioxide (scCO2) extraction of an oil rich in essential fatty acids (EFAs) from revalorized mango seed kernels and the optimization of the process by the Response Surface Methodology (RSM). In pilot-scale scCO2 experiments, pressure (23-37 MPa) and temperature (52-73 °C) were varied, using 4.5 kg of CO2. The highest experimental oil extraction yield was 83 g/kg (37 MPa and 63 °C); while RSM predicted that 84 g/kg would be extracted at 35 MPa and 65 °C. Moreover, by fine-tuning pressure and temperature it was possible to obtain an EFA-rich lipid fraction in linoleic (37 g/kg) and α-linolenic (4 g/kg) acids, along with a high oleic acid content (155 g/kg), by using a relatively low extraction pressure (23 MPa), which makes the process a promising approach for the extraction of oil from mango waste on an industrial scale, based on a circular economy model.

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RESUMEN Las fresas son frutas altamente perecederas, susceptibles a daño mecánico, deterioro y desórdenes fisiológicos durante su almacenamiento. La aplicación de recubrimientos, se presenta como una alternativa promisoria de tratamiento poscosecha, que permite mantener la calidad de las fresas. El objetivo de esta investigación fue estudiar el efecto de recubrimientos comestibles de sábila (A. vera) y alginato de sodio sobre parámetros de calidad de fresas, durante el almacenamiento refrigerado. Se evaluaron mezclas de recubrimientos comestibles de alginato de sodio y A. vera (100:0, 75:25, 50:50 y 25:75) sobre la pérdida de peso, color, firmeza, pH y acidez titulable de fresas, durante almacenamiento refrigerado (0, 3 ,9 y 12 días). Adicionalmente, se determinó el espesor y la opacidad de las películas obtenidas a partir de las soluciones formadoras de recubrimientos, utilizando el método de "casting". Los resultados mostraron que la combinación de A. vera y alginato de sodio tiene un efecto significativo en la reducción de pérdida de calidad de fresa, durante el almacenamiento en refrigeración. Todos los tratamientos con recubrimientos comestibles presentaron, al final del almacenamiento, menor pérdida de peso (7-16%), mayor firmeza (entre 1,3 a 2,1 veces más), mayor retención del color y mayor acidez titulable que las muestras sin recubrimiento (control). El espesor de las películas disminuyó con el incremento de la adición de Aloe vera y la opacidad disminuyó significativamente con la adición de la sábila en 25% y 50% en las mezclas con alginato de sodio.

ABSTRACT Strawberries are highly perishable fruits, being susceptible to mechanical injury, decay and physiological disorders during storage. Applications of edible coatings have been shown to be promising as a tool to improve the quality and extend storage. The aim of this study was to evaluate the use of Aloe vera and sodium alginate as an edible coating in postharvest quality of cold storage strawberries. The composition of edible coatings of sodium alginate and A. vera (100: 0, 75:25, 50:50 and 25:75) was studied on weight loss, color, firmness, pH and titrable acidity of strawberries during refrigerated storage (0, 3, 9 and 12 days). The thickness and opacity of the films were also determined, from the coating forming solutions using the casting method. The short shelf life and the high deterioration of the quality characteristics of strawberries during postharvest, justify to investigate alternative conservation techniques such as edible coatings, in order to reduce food loss and improve consumer acceptance The results showed that the combination of Aloe vera and sodium alginate has a significant effect in the reduction of the loss of the quality of the fruit during refrigerated storage. All coating treatments showed at the end of storage less weigth loss (7-16%), greater firmness, (between 1,3 to 2,1 more times) more color retention and greater titrable acidity tan uncoated samples (Control). The addition of Aloe vera decreased the thickness of the films and the opacity decreased significantly with the addition of Aloe vera in 25 and 50% in the mixtures with sodium Alginate.

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Background: in Colombia the consumption of fresh green mango (also known as mango "biche") is quite popular, and is consumed with lemon juice, salt, and honey. However, its high humidity content and high water activity makes of mango a highly perishable fruit, thus requiring processing alternatives. Osmotic dehydration (OD) is an interesting alternative for the conservation of mango. In OD, binary solutions (Solute + water) and ternary solutions (2 Solutes + water), have been traditionally used, however, more water removal can be achieved using ternary solutions, which leads to the improved organoleptic properties of dehydrated products. Objetives: to evaluate the kinetic water loss (WL), solutes gain (SG), weight reduction (WR), water activity (aw), and volume (Shrinking Coefficient, SC)) in green mango (Mangifera indica L. Filipino variety) osmotically dehydrated (OD). Additionally, to calculate water and solutes diffusivity (Def) for each treatment. Methods: green mango samples, with maturity scale zero, were used. Ternary solutions of sucrose at 40% and NaCl at 3, 6 and 9% were used for OD. The binary solution of sucrose with water as control treatment, was used. In the osmotic process samples were taken out at different times of OD (15, 30, 60, 90, 180, 240, and 300 min). Results: the findings show that at a higher concentration of NaCl, the dehydration kinetics was more rapid, aw and SC were smaller and water and solutes Def were higher. The samples dehydrated with the greatest solutes concentration (40 - 9%) reached the highest WL, SG, and WR with 89.52, 13.10, and 46.68%, respectively. Coefficients Defw and Defs showed a magnitude order of 10-10 m2/s, which is within the interval of dehydrated foods. Conclusions: this research showed that binary (sucrose + water) and ternary (NaCl + sucrose + water) solutions, are suitable for dehydrating green mango, however, the ternary solutions were more effective.

Antecedentes: en Colombia el consumo de mango verde fresco (también conocido como mango "biche") es popular, y se consume con zumo de limón, sal y miel. Sin embargo, su alto contenido de humedad y alta actividad de agua hace que el mango sea un fruto altamente perecedero, por lo que requiere alternativas de procesamiento. La deshidratación osmótica (OD) es una interesante alternative para la conservación de mango. En OD se utilizan tradicionalmente soluciones binarias (solute + agua) y soluciones ternarias (2 solutos + agua), sin embargo, puede removerse mayor cantidad de agua utilizando soluciones ternarias, las cuales permiten mejorar las propiedades organolépticas de productos deshidratados. Objetivos: evaluar las cinéticas de pérdida de agua (WL), ganancia de solutos (SG), reducción de peso (WR), actividad de agua (aw) y volumen (coeficiente de encogimiento, SC) en muestras de mango verde (Mangifera indica L. Variedad filipino) deshidratadas osmóticamente (OD). Adicionalmente, calcular la difusividad (Def) del agua y de solutos, en los distintos tratamientos. Métodos: se usaron mangos verdes con escala de madurez cero. En la OD se usaron soluciones ternarias compuestas por sacarosa (40%) y NaCl al 3, 6 y 9%. Como tratamiento control se usó una solución binaria de sacarosa más agua. En el proceso osmótico las muestras fueron tomadas a diferentes tiempos de OD (15, 30, 60, 90, 180, 240, and 300 min). Resultados: los resultados mostraron que al incrementar la concentración de NaCl, las WL fueron más rápidas, la aw y el SC fueron menores y las de agua y solutos mayores. Las muestras deshidratadas con la máxima concentración de solutos (40-9%), alcanzaron las mayores WL, SG y WR con valores de 59.82, 13.10 y 46.68%, respectivamente. Los coeficientes Defw and Defs mostraron orden de magnitude de 10-10 m2/s, valor que se encuentra en el intervalo para alimentos deshidratados. Conclusiones: esta investigación mostró que soluciones binarias (sacarosa + agua) y ternarias (NaCl + sacarosa + agua) son adecuadas para deshidratar mango verde, sin embargo, las soluciones ternarias fueron más efectivas.

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Background: Stevia leaves a residual flavor at moment of being consumed, and its sweet taste remains little time, whereby, encapsulation is an option to mitigate these problems. Objective: Evaluate the double emulsion system followed by complex coacervation in stevia encapsulation. Methods: The effect of the concentration of the sweetener was determined (3.5; 5; 7.5 and 10% p/p) as well as the concentration of the wall material (2.5 and 5% p/p), on the morphology, capsules size, and encapsulation capacity. The double emulsion was prepared, the coacervate was formed, and then capsules were lyophilized. The morphology and capsule size were measured before and after lyophilization by optical microscopy. From Fourier´s infrared transformed spectrometry, encapsulation capacity was analyzed. Water activity and solubility were measured in lyophilized capsules. Results: Micro and nanocapsules (minimum size of 19.39 ± 0.74µm and 62.33 ± 6.65µm maximum) were obtained. Micrographs showed that the encapsulation technique used, allows obtaining dispersed stevia capsules and those of round and homogeneous morphology. The encapsulation capacity was 84.37 ± 4.04%. The minimum value of water activity was 0.49 ± 0.01 and 17.65 ± 0.91% of solubility. Conclusions: An increased in encapsulation capacity was obtained when the highest concentration of the wall material was used. The capsule diameter increased as the sweetener concentrations increased. The formulation to 5% (p/p) of stevia and 5% (p/p) in wall material was associated with better controlled release of the sweetener, which allows establishing subsequent applications in which the sweet taste is prolonged and the stevia bitter taste concealed.

Antecedentes: La estevia deja sabor residual al ser consumida, y su sabor dulce permanece poco tiempo, por lo cual, la encapsulación es una opción para mitigar estos problemas. Objetivo: Se evaluó el sistema doble emulsión seguido por coacervación compleja en la encapsulación de estevia. Métodos: Se determinó el efecto de la concentración del edulcorante (3.5; 5; 7.5 y 10% p/p) y de la concentración del material de pared (2.5 y 5% p/p), en la morfología, tamaño de cápsulas, y capacidad de encapsulación. Se elaboró la doble emulsión, se formó el coacervado, y posteriormente, las cápsulas se liofilizaron. La morfología y el tamaño de las cápsulas, se midieron antes y después de la liofilización mediante microscopia óptica. A partir de espectrometría infrarroja de transformada de Fourier se analizó capacidad de encapsulación. En las cápsulas liofilizadas se midió actividad de agua y solubilidad. Resultados: Se obtuvieron micro y nanocápsulas (tamaño mínimo de 19.39±0.74µm y máximo 62.33±6.65µm). Las micrografías indicaron que la técnica de encapsulación usada, permite obtener cápsulas de estevia dispersas y de morfología redonda y homogénea. La capacidad de encapsulación fue 84.37±4.04%. El valor mínimo de actividad de agua fue 0.49±0.01, y solubilidad de 17.65±0.91%. Conclusiones: Se obtuvo incremento en la capacidad de encapsulación cuando se utilizó la mayor concentración del material de pared. El diámetro de las cápsulas aumentó a medida que se incrementaron las concentraciones del edulcorante. Se concluyó que la formulación a 5% (p/p) de edulcorante y de 5% (p/p) en material de pared fue el tratamiento que mejor se asocia a una liberación controlada de estevia, lo cual permite establecer posteriores aplicaciones en las que se prolongue el sabor dulce y enmascare el sabor amargo de la estevia.

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Los niños y adultos mayores representan los consumidores más vulnerables a adquirir enfermedades transmitidas por alimentos, ETA, por lo que se hace más estricto disminuir los factores de riesgo que se generan en la elaboración de alimentos dirigidos para este grupo de población. En este reporte, con el fin de disminuir los factores de riesgo de ETA a una población de niños y adultos mayores, se diseñó y se implementó un plan de saneamiento, siguiendo los lineamientos de decreto 3075 de 1997 del Ministerio de Protección Social de Colombia, y se realizó un plan de capacitación dirigido al personal manipulador implicado en los procesos de recepción, almacenamiento, empaque y distribución de materias primas en una distribuidora de alimentos. El plan de saneamiento y la capacitación permitieron incrementar los porcentajes de cumplimiento en buenas prácticas de manufactura, BPM, del 40 al 70 por ciento, estos resultados son una base sólida para garantizar la inocuidad de los alimentos y la disminución del riesgo de adquirir ETA en la población objeto de estudio.

The responsibility for providing healthy food involves all members of the production chain from input supplier to the distributor and consumer of food. Children and older adults represent the most vulnerable consumers for acquiring food-borne illness (FBI), meaning that the risk factors produced in food-processing targeted for this population group must be reduced. A clean-up plan was thus designed and implemented following the guideline laid down in decree 3075/1997 to reduce FBI risk factors in a population of children and older adults. A training plan was also conducted for handling staff involved in receiving, storing, packaging and distributing raw materials in a food distributor. The clean-up plan and training led to a 40 percent to 70 percent increase in compliance with best manufacturing practices (BPM). These results represent a solid basis for ensuring food safety and reducing the risk of acquiring FBI in the study population. This article also provides an outline for easily acquiring the necessary methodology for implementing a clean-up plan in a food industry.

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Se estudió el efecto de la agitación (180, 220, y 240rpm) sobre la pérdida de agua y la ganancia de azúcar en rodajas de pitahaya deshidratas osmóticamente, empleando soluciones osmóticas de sacarosa con dos niveles de concentración, 45 y 55°Brix. Adicionalmente, se determinó la porosidad de la pitahaya en estado fresco y deshidratado osmóticamente, y se relacionó con los niveles de agitación. Los resultados mostraron que los niveles de agitación inciden significativamente sobre la pérdida de agua, presentando mayor variación relativa para los tratamientos a 45ºBrix. La ganancia de azúcar no presentó diferencias significativas por efecto de los niveles de agitación. Lo anterior se explica por la baja porosidad de la pitahaya en estado fresco (2,78 ±0,35%), que dificulta la entrada de la molécula de sacarosa en la fruta. Los resultados sugieren que la deshidratación osmótica se perfila como una técnica de pretratamiento apropiada para la pitahaya amarilla debido a la baja ganancia de sólidos durante el proceso.

The effect of the stirring (180, 220, y 240rpm) on water loss and sugar gain in the process of osmotic dehydration of pitahaya slices was studied, using osmotic solutions of sucrose with two concentration levels, 45 and 55°Brix. Additionally, the porosity of the pitahaya in fresh and osmotically dehydrated states was determined and related to the stirring speed. The results showed that stirring level has a significant effect on water loss, with a greater relative variation for the treatments at 45°Brix. Sugar gain did not show significant differences as an effect of agitation speed. This is explained by the low porosity of the pitahaya in fresh state (2.78 ±0.35%), which hinders the entry of the sucrose molecules into the fruit. The results suggest that osmotic dehydration is emerging as an appropriate pretreatment technique for the yellow pitahaya due to the low gain in solids during the process.

Estudou-se o efeito da agitação (180, 220, e 240rpm) sobre a perda de água e o ganho de açúcar en rodelas de pitaya desidratas osmoticamente, empregando soluções osmóticas de sacarose com dois níveis de concentração, 45 e 55°Brix. Adicionalmente, se determinou a porosidade da pitaya em estado fresco e desidratado osmoticamente, e se relacionou com os níveis de agitação. Os resultados mostraram que os níveis de agitação incidem significativamente sobre a perda de água, apresentando maior variação relativa para os tratamentos a 45ºBrix. O ganho de açúcar não apresentou diferenças significativas por efeito dos níveis de agitação. O anterior se explica pela baixa porosidade da pitaya em estado fresco (2,78 ±0,35%), que dificulta a entrada da molécula de sacarose na fruta. Os resultados sugerem que a desidratação osmótica se perfila como uma técnica de pre-tratamento apropriada para a pitaya amarela devido ao baixo ganho de sólidos durante o processo.