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Introducción: los polialcoholes son usados en la industria alimentaria como edulcorantes nutritivos y muy conocidos por tener aspecto de jarabe (sirope) al disolverlos en agua. Tienen además, propiedades prebióticas. Objetivo: elaborar cerezas deshidratadas osmóticamente reemplazando de manera parcial el azúcar por lactitol a fin de obtener un producto con menor cantidad de calorías. Método: las cerezas previamente desulfitadas se candearon hasta los 55 °Bx (Bx) por el método lento de impregnaciones usando un jarabe de sacarosa y lactitol. Se realizaron tres tratamientos: T1 con 25 % de lactitol y 75 % de sacarosa, T2 con 50 % de sacarosa y 50 % de lactitol, los mismos fueron contrastados contra el Control T0 de 100 % de sacarosa. Se midieron las variables Humedad, °Bx de la solución y de la pulpa, y luego se realizó un análisis sensorial para medir la aceptación y preferencia de las formulaciones. El test de aceptación, se hizo mediante una encuesta con una escala hedónica (estructurada en 5 puntos) y otro test de preferencia. Los productos terminados fueron analizados por 64 jueces seleccionados al azar.Resultados: en comparación, T0 disminuyó la humedad hasta 23 %, T1 hasta el 35 % y T2 hasta 41 %. Todos los tratamientos alcanzaron 55 °Bx. El aumento de los sólidos solubles en la pulpa se ajustó con una ecuación polinómica de segundo orden con un alto nivel de ajuste. Del análisis sensorial se desprende que la formulación T2 fue la más aceptada, luego la T1 y la T0 fue la menos elegida.Conclusiones: el estudio muestra que es posible producir cerezas en conserva con hasta un 25 % de reducción en el valor calórico como el caso de T2 y 13 % de reducción en el valor calórico con la formulación T1. Estas dos formulaciones pueden ser consideradas reducidas en azúcar. Introduction: polyalcohols are used in the food industry as nutritional sweeteners. They are well known for having a syrupy appearance when dissolved in water, and have prebiotic properties. Objective: To produce osmotically dehydrated canned cherries by partially replacing sucrose with lactitol in order to obtain a product with fewer calories. Methods: After sulphate removal, cherries were candied to 55 °Bx by the slow impregnation method using a solution with different concentrations of sucrose syrup and lactitol. We compared the following three formulations: T1 composed of 25% lactitol and 75% sucrose; T2 composed of 50% sucrose and 50% lactitol, and T0 composed of 100% sucrose as control. Variables measured were moisture, ºBx of the solution and of the cherry pulp. Finally, a sensory analysis was performed to measure acceptance and preference of the formulations. The acceptance test was carried out through a survey with a hedonic scale (structured in 5 points) and another preference test. The finished products were analyzed by 64 randomly selected judges. Results: Moisture was reduced to 23%, 35%, and 41% in formulations T0, T1 and T2, respectively. All treatments reached 55° Bx. The increase in soluble solids in the pulp was adjusted with a second-order polynomial equation with a high level of fit. According to the sensorial analysis, formulation T2 formulation was the most preferred, followed by T1 and T0. Conclusions: our study showed that it is feasible to produce canned cherries in syrup with a reduction of up to 25% when using formulation T2 and a reduction of 13% when using formulation T1. These two formulations can be considered as reduced in sugar. Introdução: os poliálcoois são usados na indústria alimentar como adoçantes nutritivos e são bem conhecidos por terem uma aparência de um xarope quando dissolvidos em água. Apresentam ainda propriedades prebióticas. Objetivo: elaborar cerejas osmoticamente desidratadas, substituindo parcialmente o açúcar pelo lactitol para obter um produto com menos calorias. Método: as cerejas previamente dessulfuradas foram aquecidas a 55 °Bx pelo método de impregnação lenta usando um xarope de sacarose e lactitol. Foram realizados três tratamentos: T1 com 25 % de lactitol e 75 % de sacarose, T2 com 50 % de sacarose e 50 % de lactitol; foram contrastados com o controle T0 de 100 % de sacarose. Foram medidas as variáveis Humidade, °Bx da solução e da polpa, em seguida, foi realizada uma análise sensorial para medir a aceitação e preferência das formulações. O teste de aceitação foi realizado por meio de uma pesquisa com escala hedônica (estruturada em 5 pontos) e outro teste de preferência. Os produtos acabados foram analisados por 64 juízes selecionados aleatoriamente. Resultados: em comparação, T0 diminuiu a humidade até 23 %, T1 até 35 % e T2 até 41 %. Todos os tratamentos atingiram 55 °Bx. O aumento dos sólidos solúveis na polpa foi ajustado com uma equação polinomial de segunda ordem com um alto nível de ajuste. A análise sensorial mostra que a formulação T2 foi a mais aceite, em seguida T1 e a T0. Conclusões: o estudo mostra que é possível produzir cerejas em conserva com redução de até 25 % no valor calórico, como no caso do T2, e redução de 13 % no valor calórico com a formulação T1. Essas duas formulações podem ser consideradas reduzidas em açúcar. Fil: Maldonado, Mariela Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Tecnológica Nacional. Facultad Regional de Mendoza; Argentina Fil: Fonarsin, Emiliano. Universidad Tecnológica Nacional. Facultad Regional de Mendoza; Argentina Fil: González Pacheco, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Tecnológica Nacional. Facultad Regional de Mendoza; Argentina

Time-variable average effective diffusion coefficients of sodium in the skin and flesh were determined using Macroscopic Mass Balances from experimental data obtained during debittering of green olives, variety Arauco at temperatures of 15, 20 and 25C and lye concentrations of 1.50, 2.25 and 3.00% of NaOH. The effective diffusion coefficient of sodium increased with treatment time at both surfaces of the skin, while it varied very little within the flesh, and in many cases, remained almost constant during the debittering process. In general, the diffusion coefficients determined in the present study were within an order of magnitude of 10 -10 m 2 /s for the flesh during most of the treatment time, while for the skin, they were of the order of 10 -12 m 2 /s for the initial treatment times. Macroscopic mass balances are a simple mathematical method that can be used in lieu of more common numerical techniques, to evaluate variable diffusion coefficients providing accuracy and greater detail of the whole phenomena.

The present study reports a simple method, both mathematical andexperimental, to determine variable effective diffusion coefficients for sodiumthrough the skins of olives. Skins removed from green olives, variety Arauco(also known as Criolla), were studied using a lye concentration of 2.25% (w/w) of NaOH at 20C. The diffusion of sodium was evaluated through fresh skinsand previously alkali-treated skins. The measured values of effective diffusioncoefficients for untreated (fresh) olive skins increased two orders of magnitudeduring the processing time, from 10 - 12 to 10 - 10 m 2 /s. Whereas, the effectivediffusion coefficients determined for previously treated olive skins were of theorder of 10 - 10 m 2 /s and increased very little with treatment time. INTRODUCTION In biological systems, the phenomena of solute diffusion can be studiedat different structural levels in order to evaluate their influence in variousagronomic and processing treatments.The diffusion of sodium chloride has been investigated by several authorsin various foodstuffs; in pork meat by Kormendy and Ganter (1958) and Wood(1966); in pickles by Pflug

A diffusion model for a composite flat plate, consisting of a thin skin of thickness δ, and a thicker flesh of thickness L, with constant flesh and skin effective diffusion coefficients (D F and D S ) was successfully adjusted to the experimental data obtained during the debittering of green olives variety Arauco (also known as Criolla) at 15C, 20C and 25C and lye concentrations of 1.50%, 2.25% and 3.00% of NaOH. The D F values ranged between 1.64 x 10 -10 and 9.20 x 10 -10 m 2 /s, and increased with increasing temperature and lye concentration. The D S values ranged between 1.27 × 10 -12 and 5.63 × 10 -12 m 2 /s, and also increased with increasing lye concentration and temperature. Activation Energies (Ea) of diffusion in the flesh and the skin were evaluated with an Arrhenius-type relationship. The Ea values for the flesh were 93.2, 72.7 and 64.8 kJ/mol, and 92.7, 91.46 and 33.67 for the skin for lye concentrations of 1.50%, 2.25% and 3.00%, respectively.

The change in the concentration of sodium and calcium ions in the olive flesh and in the lye during the debittering process was quantified. The average concentration of Na increased from 0.0045 to 0,395 meq Na/g of olive flesh and the concentration of Ca increased from 0.018 to 0.0252 meq Ca/g of olive flesh. The firmness of the olives decreased almost linearly from 375 gf to 235 gf during the alkali treatment. The olives also suffered a 25.9% loss in their initial content of reducing sugars. A hypothetical simplified description of the dynamic of ionic charge changes and unwinding of the pectinic structure during the debittering process of green olives has been proposed. In addition, the effective diffusion coefficients were calculated for sodium and calcium using a diffusion model for a composite flat plate and constant diffusion coefficients. The coefficients for both solutes were in the order of 10–12 m2/s for the skin and 10–10 m2/s for the flesh. In both cases, the diffusion coefficients of Na were larger than the diffusion coefficients of Ca. Se ha cuantificado el cambio en la concentración de sodio y calcio en la pulpa y en la lejía durante el tratamiento alcalino de aceitunas. La concentración promedio de sodio en la pulpa aumentó de 0,0045 a 0,395 meq Na/g mientras que la de calcio creció de 0,018 a 0,0252 meq Ca/g. La textura de las aceitunas disminuyó casi linealmente de 375 gf a 235 gf durante el tratamiento alcalino. Las aceitunas sufrieron una perdida de azúcares reductores del 25.9%. Se ha propuesto una hipotética y simplificada descripción de la dinámica de los cambios de carga iónica y el desenrollamiento de las pectinas durante el desamarizado de las aceitunas. También se calculó el coeficiente efectivo de difusión para sodio y calcio usando un modelo de difusión para una placa compuesta. Los coeficientes resultaron en el orden de 10–12 m2/s para la piel y 10–10 m2/s para pulpa. En ambos casos el coeficiente de difusión de Na fue mayor que el de Ca. EEA Mendoza Fil: Maldonado, Mariela. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentina Fil: Maldonado, Mariela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Zuritz, Carlos A. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Zuritz, Carlos A. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentina Fil: Wuilloud, Rodolfo G. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Básicas; Argentina Fil: Wuilloud, Rodolfo G. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias. Instituto de Ciencias Básicas; Argentina Fil: Bageta, Carlos. Universidad Nacional de Cuyo. Facultad Ciencias Agrarias; Argentina Fil: Terreni, Jorge. Universidad Nacional de Cuyo. Facultad Ciencias Agrarias; Argentina Fil: Sanchez, María José. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Mendoza; Argentina

Aceitunas verdes variedad Arauco fueron tratadas con soluciones de hidróxido de sodio al 2,5%. Estas fueron luego sometidas a dos procesos de lavado con agua corriente. Posteriormente, las aceitunas fueron curadas en salmueras con concentraciones de 7%, 10% y 13% de cloruro de sodio. Durante este proceso de curado, se cuantificó la pérdida de azúcares reductores desde, y la difusión de cloruro de sodio hacia el interior de las aceitunas. Durante este período se calcularon los coeficientes efectivos de difusión de ambos solutos en la piel y la pulpa, utilizando un modelo de difusión en una esfera hueca compuesta. Los coeficientes efectivos de difusión de ambos solutos en la piel estuvieron en un rango entre 8,27x10-14 m2 /s y 4,04x10-13 m2 /s. Los coeficientes de la pulpa variaron entre 2,92x10-9 m2 /s y 3,99x10-9 m2 /s para el cloruro de sodio, y entre 9,76x10-11 m2 /s y 2,22x10-10 m2 /s para los azúcares reductores. The green olive variety Arauco were debittered using lye concentrations of, 2.50% NaOH. They were then subjected to two rinsing processes with tap water. Next, the olives were cured with brines at 7%, 10% and 13% sodium chloride concentration. During this curing process, the loss of reducing sugars from the olives, and the diffusion of sodium chloride into the olives were quantified. Effective diffusion coefficients of both solutes in the skin and the flesh were calculated for this period using a diffusion model for a composite hollow sphere. The skin effective diffusion coefficients for both solutes ranged from 8.27x10-14 m2/s to 4.04x10-13 m2/s. The flesh coefficients varied from 2.92x10-9 m2/s to 3.99x10-9 m2/s for sodium chloride and from 9.76x10- 11 m2/s to 2.22x10-10 m2/s for reducing sugars. Fil: Maldonado, Mariela Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria Mendoza; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina Fil: Zuritz, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Nacional de Cuyo. Facultad de Ciencias Agrarias; Argentina Fil: Miras, N.. No especifíca

A sodium diffusion model in a hollow sphere was adjusted with a high degree of correlation (0.97 S and D L , respectively. With lye at 2.25% of NaOH at 15oC, 20oC and 25oC, the D L values ranged between 2.27x10 -09 and 4.24x10 -09 m 2 /s, while the D S values ranged from 1.49x10 -12 to 7.38x10 -12 m 2 /s. The diffusion coefficients increased with temperature. Activation energies of diffusion of sodium were 45.07 and 115.28 kJ/mol, for the pulp and the skin respectively.

The diffusion of sodium in green olives, variety Arauco/Criolla was quantitatively measured during the debittering process with lye of 1,50; 2,25 y 3,00%, at 20 ºC. With lye of 1,50%, the diffusion is apparently controlled by skin resistance resulting in smaller sodium concentrations and a more uniform debittering. With lye of 3,00%, the diffusion is more affected by flesh resistance, resulting in greater sodium concentrations and less uniform debittering. With lye of 2,25%, the diffusion of sodium is controlled by skin resistance at first and by flesh resistance thereafter. From this study, a final average concentration of 0,20 meq-Na/g-olive could be inferred as an appropriate treatment value. The experimental data were correlated with the equation: C=Ci+A*t-B (t=diffusion time), then A and B were correlated with sodium penetration distances. Se cuantificó la difusión de sodio en aceitunas verdes variedad Arauco (Criolla) durante el tratamiento alcalino con lejías al 1,50; 2,25 y 3,00%, a 20 ºC. Con lejía de 1,50%, la difusión estaría controlada por la resistencia de la epidermis, resultando en menores concentraciones de sodio en la pulpa y en un tratamiento alcalino más uniforme. Con sosa al 3,00%, la difusión estaría más afectada por la resistencia de la pulpa, resultando en mayores concentraciones de sodio en la pulpa y menor uniformidad de tratamiento. Con lejía de 2,25%, la difusión estaría dominada al principio por la resistencia de la epidermis y luego por la resistencia de la pulpa. Este estudio permite inferir un valor final promedio de tratamiento de 0,20 meq-Na/g-aceituna como apropiado. Los datos experimentales se correlacionaron con la ecuación: C=Ci+A*t-B (t=tiempo de penetración), luego A y B se correlacionaron con la distancia de penetración.

The diffusion of sodium in green olives, variety Arauco/Criolla was quantitatively measured during the debittering process with lye of 2,25%, at 15, 20 y 25 ºC. The experimental data were correlated with the equation: C=C1 + P0 x e -P1X x senh (P2t) x eP3Te (X=diffusion distance, t=time, Te=treatment temperature) and this equation was used to calculate the sodium concentration gradients (dC/dX). Were required 23 hours at 15 ºC and 7 hours a t 25 ºC in order to attain the same final concentration gradient. Matching the final concentration gradients with that of the treatment at 20 ºC, the treatments at 15 and 25 ºC could be ended at 15 and 4,5 hours respectively. These findings quantitatively corroborate the significance of controlling the lye temperature. Se cuantificó la difusión de sodio en aceitunas verdes variedad Arauco (Criolla) durante el tratamiento alcalino con lejía de 2,25%, a 15, 20 y 25 ºC. Los datos experimentales se correlacionaron con la ecuación: C=C1 + P0 x e -P1X x senh (P2t) x eP3Te (X=distancia de difusión, t=tiempo, Te=temperatura de tratamiento) y con ésta se calcularon los gradientes de concentración de sodio (dC/dX). Para alcanzar el mismo gradiente de concentración final, se requirieron 23 horas a 15 ºC y 7 horas a 25 ºC. Igualando los gradientes de concentración final al del tratamiento a 20 ºC, los procesos a 15ºC y 25ºC se podrían finalizar a las 15 y 4,5 horas respectivamente. Esto confirmaría cuantitativamente la importancia de controlar la temperatura de la lejía en el tratamiento alcalino.

A diffusion model for a composite-wall, hollow semi-infinite cylinder, consisting of a thin skin and a thicker flesh, with constant flesh and skin effective diffusion coefficients, DL and DS, respectively, was successfully adjusted to the experimental data obtained during the debittering of green olives variety Arauco or Criolla at 15 ºC, 20 ºC and 25ºC and lye concentrations of 1.50 %, 2.25 % and 3.00 % of NaOH. The DL values ranged between 7.18x10-11 and 1.18x10-09 m2/s, and increased with increasing temperature and lye concentration. The DS values were almost two order of magnitude less than the DL values, and also increased with increasing lye concentration and temperature. They ranged between 4.30x10-12 y 9.32 x10-12 m2/s. Activation energies of diffusion of sodium were respectively for the pulp, 85.48, 77.03 and 71.90 kJ/mol, and 30.24; 29.38 and 22.88 kJ/mol for the skin, for lye concentrations of 1.50 %, 2.25 % and 3.00 %. Un modelo de cilindro hueco semi-infinito con pared compuesta por la epidermis y la pulpa, con coeficientes de difusión efectivos constantes, DS y DL respectivamente, se ajustó a los datos experimentales durante el tratamiento con hidróxido sódico de aceitunas verdes de la variedad Arauco o Criolla, con concentraciones de lejía de 1,50 %, 2,25 % y 3,00 %, a temperaturas de 15 ºC, 20 ºC y 25 ºC. Los valores de DL variaron entre 7,18x10-11 y 1,18x10-09 m2/s, y aumentaron con la temperatura y la concentración de lejía. Los valores de DS, entre 4,30x10-12 y 9,32 x10-12 m2/s, fueron por lo menos dos órdenes de magnitud inferior a los coeficientes DL, y también se incrementaron en función de la temperatura y la concentración de lejía. La energía de activación para la difusión de sodio, para la pulpa fue de 85,48; 77,03 y 71,90 kJ/mol y de 30,24; 29,38 y 22,88 kJ/mol para la epidermis, para concentraciones de NaOH de 1,50 %; 2,25 % y 3.00 % respectivamente.