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© 2021 by the authors., The physiological and endocrine benefits of sustained exercise in fish were largely demonstrated, and this work examines how the swimming activity can modify the effects of two diets (high-protein, HP: 54% proteins, 15% lipids; high-energy, HE: 50% proteins, 20% lipids) on different growth performance markers in gilthead sea bream juveniles. After 6 weeks of experimentation, fish under voluntary swimming and fed with HP showed significantly higher circulating growth hormone (GH) levels and plasma GH/insulin-like growth-1 (IGF-1) ratio than fish fed with HE, but under exercise, differences disappeared. The transcriptional profile of the GH-IGFs axis molecules and myogenic regulatory factors in liver and muscle was barely affected by diet and swimming conditions. Under voluntary swimming, fish fed with HE showed significantly increased mRNA levels of capn1, capn2, capn3, capns1a, n3, and ub, decreased gene and protein expression of Ctsl and Mafbx and lower muscle texture than fish fed with HP. When fish were exposed to sustained exercise, diet-induced differences in proteases’ expression and muscle texture almost disappeared. Overall, these results suggest that exercise might be a useful tool to minimize nutrient imbalances and that proteolytic genes could be good markers of the culture conditions and dietary treatments in fish., This study was supported by the projects from the “Ministerio de Economía y Competitividad” (MINECO) AGL2015-70679-R and RTI2018-100757-B-I00 to J.G. and J.B., and the “Xarxa de Refèrencia d’R+D+I en Aqüicultura” and the 2017SGR1574 from the “Generalitat de Catalunya”. M.P.- A., I.G.-P. and E.J.V. were supported by predoctoral fellowships from the MINECO, BES-2016-078697, PRE2019-089578 and BES-2013-062949, respectively.

The different intensities of common culinary techniques (boiling, baking and microwaving) produce several changes that reduce the nutritional and physical properties of potatoes. This study evaluated the effect of those cooking methods on the quality of commercial potato tubers (Agata, Kennebec, Caesar and Red Pontiac). The higher weight losses were obtained for baking, but the potato softening depended on the cultivar. Color losses were independent of the intensity of the treatment; however, microwaving promoted a prompt starch gelatinization with respect to the other methods. The resistant starch retention of baking and microwaving was higher than that of boiling, and the maximum retention of bioactive compounds was obtained with the lower core temperature during boiling, as well as higher temperature and shorter baking time and the lower power and longer microwaving time. Principal component analysis revealed significant relationships between the instrumental and functional properties of cooked potatoes. (C) 2015 Published by Elsevier Ltd.

BACKGROUNDThe commercial potato cultivars are diverse not only in their physical characteristics but also in their nutritional compositions and their content of functional compounds (resistant starch, total phenolic content and antioxidant activity), but there is little information about these differences. The aim of this study was to characterise the nutritional value (focusing on carbohydrates and functional compounds) and instrumental parameters of eight potato cultivars consumed in Spain and to determine whether these parameters are useful for classifying the cultivars.; RESULTSSignificant Pearson's correlations were found due to the common and complex interactions between the constituents of potatoes and their properties (P < 0.05). Principal component analysis revealed the correlations among the physicochemical properties, and the first two principal components explained 56.84% of the variance among the cultivars studied.; CONCLUSIONThe eight cultivars could be classified into three groups: (1) Red Pontiac, Caesar, Kennebec, Agria and Cherie cultivars, (2) Agata and Monalisa cultivars and (3) Spirit cultivar. The results demonstrated that certain nutritional and functional parameters indicated the potential efficacy of different cultivars to satisfy the nutritional needs of consumers, improving the knowledge on the biochemical basis of potato processing to obtain higher-quality products. (c) 2015 Society of Chemical Industry

The aim of this work was to investigate the effect of using ultrasound or edible coating as a possible alternative to blanching on the quality of vacuum-packaged potato strips. The treatments assessed were blanching (85 °C, 3.5 min), coating with 20 g L-1 alginate and sonicating (40 kHz, 5 min) in an ultrasonic bath containing a 20 g L-1 citric acid solution. Vacuum-packaged samples were stored up to 12 days at 3 ± 1 °C. The pH, polyphenol oxidase (PPO) activity, sugars and microbial load were assessed. Also, the colour, shear-force and dry matter of the treated and fried potato strips as well as the oil adsorption and acrylamide after frying were evaluated. The PPO activity of the treated samples was not significantly different over time (p > 0.05). The treatments applied did not affect the attributes of the fried potato strips over time; there were no significant changes in oil absorption, acrylamide content or colour (p > 0.05). However, the visual quality of sonicated packaged potato strips was significantly better than that of the other treatments after storage. The loss of the texture of blanched potatoes was remarkable (p < 0.05) before and after frying. Sonicated samples maintained mesophilic bacteria counts better than blanched and alginate coated vacuum-packaged potato strips.

This work investigates the effectiveness of alginate and chitosan edible coatings and ascorbate and lactate calcium salts combined with a low permeable film to maintain the quality of fresh-cut pineapple through 15 days at 4C. Respiration rate, color, firmness, pH, ripening index, juice leakage, total soluble solids in juice leakage and ascorbic acid content were measured. Neither chitosan nor alginate coatings reduce the respiration rate of fresh-cut pineapple and oxygen values of less than 2% were obtained at the end of the storage. Significant correlations were found between ripening index, pH and luminosity, indicating that these parameters could point to the quality of the pineapple. According to our findings, a calcium lactate dip combined with the use of low permeable film retards the ripening process and reduces the loss of luminosity, enhancing the quality of fresh-cut pineapple for up to 15 days at 4C. Practical Applications The juice leakage and color changes are the major causes of deterioration of fresh-cut pineapple during storage time. Edible coatings and calcium dips are commonly used to prolong the shelf life of fresh-cut fruits. The present study demonstrates that neither alginate nor chitosan slow down the gas exchange of fresh-cut pineapple tissue. Calcium lactate prolongs the shelf life of fresh-cut pineapple by preventing juice leakage production and luminosity reduction. Calcium lactate dips are simple treatments that can improve the marketability of fresh-cut pineapple.

This article studies the efficacy of an edible coating based on Aloe vera gel at four different concentrations (0, 1, 5, 15% (v/v)) in maintaining the quality of fresh-cut kiwifruit. The kiwifruit slices were packaged under passive atmosphere and stored at 4 ± 1 °C. Quality attributes such as colour and texture (firmness and texture profile analysis), titratable acidity, total soluble solids, pectin content, microbial load and sensory parameters were evaluated during storage. In general, Aloe vera coating reduced respiration rates and microbial spoilage in sliced kiwifruit. After seven days of storage, the mesophilic load dropped by approximately one logarithmic unit for slices coated with 15% and 5% Aloe vera. Total pectin depolymerization was also lower in the treated samples and the texture of the uncoated samples deteriorated more rapidly than the treated slices during storage. Furthermore, due to the atmospheric composition and the microbial load, the quality of the control samples declined after six days of storage. Our results show that an Aloe vera coating improved the quality of stored kiwifruit slices. The best results obtained in the instrumental texture profile and in the preference panel test were with the 5% coating, indicating that this may be a healthy alternative coating for fresh-cut kiwifruit.

This study aimed to assess the effect of sous vide cooking on the total and resistant starch content, color, and shear force in three potato cultivars (Agria, Agata, and Carrera). Potato strips were also cooked by three common treatments (boiling, frying, and microwaving) to evaluate the differences between the methods. According to principal component analysis (PCA), sous vide-processed cv. Agria and Agata potato strips were grouped with boiled samples, in contrast, cv. Carrera sous vide samples were grouped with microwaved samples. Higher water losses were associated with microwaved potatoes due to the diffusion of water inside the tuber. In addition, a significant decrease in shear force was obtained after microwaving and sous vide cooking (p < 0.05) irrespective of the treatment strength. The three cultivars became less bright, and the intensity of the color decreased; however, variations in the cook value (C100, min) between treatments did not affect the lightness and hue angle. Regardless of the initial value of resistant starch and the intensity of the cooking process, all of the cultivars reached a final content of less than 5%. From our results, in-pack sterilization may be considered for application in the food industry as a technology that has a similar impact to conventional cooking treatments used on potato products.

© 2015 Elsevier Ltd. Acrylamide formation during the production of French fries is attributed to Maillard reactions from reducing sugars and asparagine and is dependent on the frying temperature. Low reducing sugars content in potatoes has been recommended to produce fried potato products. However, the influence of the complexity of the potato medium in the chemical reactions that promote the acrylamide formation during deep frying are not well understood. In this study, three potato cultivars (Kennebec, Red Pontiac and Agria) commonly used for fried potato products were evaluated to determine the relationships between the precursors of acrylamide in the fresh potato tubers and the properties of the fried potato strips with the acrylamide content after frying. Frying experiments were conducted at three conditions (time-temperature) to obtain French fries of similar visual colour. Acrylamide formation increased with frying temperature but different behaviour was observed between cultivars. For Red Pontiac, a remarkably increase in acrylamide content was found at 170 °C (~40%) together with the increase in colour. However, lower oil uptake and higher moisture content was obtained as temperature increase. Significant positive correlations were observed between the acrylamide level and the reducing sugars and sucrose content on fresh potatoes (0.652, 0.699, p = 0.01, respectively). The acrylamide content obtained in Agria cultivar may be obtained from the hydrolysis of sucrose during the frying process. In fried potato strips, positive significant correlation was found between the shear force and acrylamide (0.749, p = 0.01). The significant correlations obtained between colour, and texture, colour and oil uptake and texture and acrylamide content indicate the intrinsic relationship between the properties of the fried potato strips and the acrylamide content.

The effect of temperature on the respiration rate and texture of fresh cut pineapple was studied over the course of 10days of storage. The thermal exchange between the pineapple trays and the cooling environment was simulated using the finite element method and tested at 6°C. The temperatures on pineapple wedges differed between the cold point and points near the surface, indicating that the respiration rate may be affected in pineapple subjected to temperature abuse. The experimental respiration rates obtained were used to develop a model relating respiration to O2and CO2concentrations at different temperatures using the closed system method. The O2consumption and CO2production of pineapple wedges was accurately modeled using Michaelis–Menten kinetics. The texture degradation of pineapple wedges follows a zero-order kinetic reaction at different temperatures and the thermal dependence of the model’s parameters for both respiration rate and texture degradation was described by Arrhenius-type equations.

Osmotic treatment (OT) has been applied to infuse phenolic compounds into a model food. Two commercial grape extracts were used as a source of phenolics, a grape seed extract (GSE) and a white grape marc extract (WGME). Three different concentrations of total phenolics were applied with and without presence of osmo-active solute (50 g/100 g and 0 g/100 g of sucrose) in the osmotic solution (OS). With a 50 g/100 g sucrose and a total phenolic content in OS ranging from 3 g/L to 15 g/L and operating time up to 8 h, the final total phenolic content in the osmo-treated model food was between 815 mg GAE/kg and 7176 mg GAE/kg. That is between the 0.5 and 1.5 times higher than that of the richest fruits. A soaking process with the same phenolic content but with no sucrose in OS led to a total phenolic content in the model food that was between 80% and 100% higher. Mass transfer of the major phenolics infused into the model food during OT and soaking process was characterized considering the diffusional approach and Peleg's model. Progress of total and individual phenolic content fitted well both models with the exception of the flavan-3-ol dimer concentration.

Osmotic treatment (OT) is applied to obtain high quality intermediate moisture products impregnated with particular solutes, for instance phenolics from commercial grape seed extracts. To investigate how the nature of osmo-active solutes affects mass transfer of grape phenolics in a solid model food, sucrose, sodium chloride and glycerol were used as osmo-active solutes. Mass transfer of total and individual grape phenolics of low molecular weight were characterized by the diffusional approach and Peleg’s model. Of all the osmo-active solutes investigated, sodium chloride led to the highest phenolic infusion rate for each individual phenolic analyzed. With all the osmo-active solutes, the non esterified flavan-3-ol monomers showed a higher initial rate of phenolic mass transfer (1/k1) than their corresponding gallate esters and flavan-3-ol dimers. The phenolic content in the osmo-treated model food was similar or higher than that of the richest fruits and vegetables in all the conditions tested, thus increasing the antioxidant capacity of the product.

The effect of ultrasound (US) (40 kHz, 200 W, 3 min), blanching (85 °C, 3.5 min), and the combination of both methods was evaluated on the quality of vacuum-packaged potato strips stored at 3 ± 1 °C for up to 10 days. For this study, two cultivars of potatoes were assessed. For blanched Agata samples, the lightness (L*) decreased over 12 % (p < 0.05). Moreover, their hue increased up to 100, obtaining lesser yellow potato strips. In contrast, US did not affect the hue values. The losses of firmness of blanched potato strips were notable (35 % for Agata and 51 % for Agria), whereas US did not change this property (p < 0.05). Nevertheless, no significant differences were found in the total starch content at 10 days. Agata and Agria showed different metabolic behaviors of sucrose in the refrigerated storage. Therefore, Agria cultivar retained better color after frying. These results suggest that US had less impact on color and improve the firmness in vacuum-packaged potato strips with no added chemicals.

Osmotic dehydration has been assessed as an operation for obtaining solid foodstuffs supplemented with grape phenolics. However, mass transfer in multicomponent osmotic solutions during OD needs to be described appropriately if the infusion of target solutes, in this case phenolics with antioxidant activity, is to be better controlled. The effective diffusion coefficients of moisture, total phenolics, and the major individual phenolics of low-molecular-weight (caftaric acid, coutaric acid, caffeic acid, coumaric acid, ferulic acid, and rutin) were evaluated during the OD of a model food with a concentrated red grape must. An increase in the concentration of soluble solids above 50° Brix decreased the level of penetration of phenolics in the model food.

A decolourisation process using ion-exchange resins (Lewatit S-5328-A) was applied to wine vinegar on a pilot scale. In the fixed experimental conditions, the decolourisation efficiency (DE) was 75.5% and the total phenolic compounds removed (DPTI) was 60%. Additional analysis of the adsorption selectivity of the ion exchange showed that the phenolic fraction involved in browning decreased. The resin had a greater affinity for the hydroxycinnamic acids (99% removed), (+) catechin and gallic acid (both 85% removed). Vinegar colour enhancement was also conducted. The colour of a browned vinegar improved to normal values after the adsorption process.

[EN] Several professors of UPC, UB, UAB, UIB, UOC and URV are investigating on "feed forwarding", a formative evaluation which is fed back immediately, which is not limited to "right-wrong", which is guiding rather than resolving, which is sufficiently individualized, which motivates reflection - action and which garantees a sustainable task for students and professors. The application inside the UPC has fallen on "Mathematics" at the College of Agriculture of Barcelona, during the first semester. It has designed an experience transferable to more topics, using props NTIC, and it has analyzed the level of achievements resulting from their deployment. To encourage learning, some questionnaires about the discipline were sent out, with and without feedback. Students have to first consider a feedback questionnaire, repeatedly until they have successfully answered all the questions, and then have faced a similar questionnaire without feedback. The experience has carried out involving two hundred students, with five double questionnaires generated by means of WIRIS (corresponding to the five themes of the course), using the Moodle 2.6.2. We have studied the contribution to academic achievement and satisfaction of agents, confirming increased dedication to matter, improvements (not maintained) in learning and positive evaluation of the step taken., [ES] Docentes de UPC, UB, UAB, UIB, UOC y URV investigamos sobre una evaluación formativa "feedforwarding", que realimente de inmediato, que no se limite al "correcto-incorrecto", que guíe más que resuelva, que sea suficientemente individualizada, que motive reflexión - acción y que genere un trabajo sostenible para alumnos y profesores. La aplicación en la UPC ha recaído sobre "Matemáticas" del primer cuatrimestre en la Escuela Superior de Agricultura de Barcelona. Se ha diseñado una experiencia transferible a más asignaturas, que usa apoyos de NTIC y que permite analizar eventuales logros resultantes de su despliegue. Para fomentar el aprendizaje se han administrado cuestionarios sobre la disciplina, con y sin realimentación. Los estudiantes han considerado primero un cuestionario con realimentación reiterada hasta que responden bien todas las preguntas y, posteriormente, han afrontado un cuestionario similar sin realimentación. Se ha actuado sobre unos doscientos estudiantes, con cinco cuestionarios dobles generados con WIRIS (correspondientes a los cinco temas de la asignatura), empleando la versión Moodle 2.6.2. Se ha estudiado la contribución al rendimiento académico y la satisfacción de los agentes, constatándose aumento de dedicación a la materia, mejoras (no duraderas) en el aprendizaje y valoración positiva del paso dado.

Docentes de UPC, UB, UAB, UIB, UOC y URV investigamos sobre una evaluacion formativa "feedforwarding", que realimente de inmediato, que no se limite al "correcto-incorrecto", que guie mas que resuelva, que sea suficientemente individualizada, que motive reflexion - accion y que genere un trabajo sostenible para alumnos y profesores. La aplicacion en la UPC ha recaido sobre "Matematicas" del primer cuatrimestre en la Escuela Superior de Agricultura de Barcelona. Se ha disenado una experiencia transferible a mas asignaturas, que usa apoyos de NTIC y que permite analizar eventuales logros resultantes de su despliegue. Para fomentar el aprendizaje se han administrado cuestionarios sobre la disciplina, con y sin realimentacion. Los estudiantes han considerado primero un cuestionario con realimentacion reiterada hasta que responden bien todas las preguntas y, posteriormente, han afrontado un cuestionario similar sin realimentacion. Se ha actuado sobre unos doscientos estudiantes, con cinco cuestionarios dobles generados con WIRIS (correspondientes a los cinco temas de la asignatura), empleando la version Moodle 2.6.2. Se ha estudiado la contribucion al rendimiento academico y la satisfaccion de los agentes, constatandose aumento de dedicacion a la materia, mejoras (no duraderas) en el aprendizaje y valoracion positiva del paso dado.

Vinegar decoloring by adsorption with exchange resins was studied and the decoloring capacity of three commercial resins as adsorbent material evaluated. The regeneration of the resins was also studied. The decoloring capacity of the selected resin (Lewatit S-6328-A) was compared with a powder activated carbon which is currently used as an adsorbent in the vinegar industry for decolorization. For a batch process with white and rose vinegars with resin Lewatit S-6328-A (10 g/l for white and 20 g/l for rose) at equilibrium the maximum decolorization efficiency was 69% and 72%, respectively. In the continuous process with a packed column on bench scale, the pseudo-contact time (ratio resin volume and vinegar flow-rate) is the operation factor which determines the decolorization level. The maximum level of decolorization for white and rose vinegars in continuous process was practically the same. The pseudo-contact time required to obtain the maximum decolorization for rose vinegar was almost three times that required for white vinegar. The adsorption of coloured compounds with exchange resins in continuous packed columns seems to be technically feasible, and the results of this work form the backbone of subsequent studies of scaling up for vinegar decolorization. The possibility of packing the resins into a column means that a new continuous process can be used for vinegar decolorization.

The commercial potato cultivars are diverse not only in their physical characteristics but also in their nutritional compositions and their content of functional compounds (resistant starch, total phenolic content and antioxidant activity), but there is little information about these differences. The aim of this study was to characterise the nutritional value (focusing on carbohydrates and functional compounds) and instrumental parameters of eight potato cultivars consumed in Spain and to determine whether these parameters are useful for classifying the cultivars.Significant Pearson's correlations were found due to the common and complex interactions between the constituents of potatoes and their properties (P0.05). Principal component analysis revealed the correlations among the physicochemical properties, and the first two principal components explained 56.84% of the variance among the cultivars studied.The eight cultivars could be classified into three groups: (1) Red Pontiac, Caesar, Kennebec, Agria and Cherie cultivars, (2) Agata and Monalisa cultivars and (3) Spirit cultivar. The results demonstrated that certain nutritional and functional parameters indicated the potential efficacy of different cultivars to satisfy the nutritional needs of consumers, improving the knowledge on the biochemical basis of potato processing to obtain higher-quality products.

In the industry of fresh-cut potatoes, controlling browning and delaying the loss of texture are important factors to obtain a high-quality product. The use of ultrasound can avoid these undesirable phenomena due to its power to inactivate enzymes by breaking the cell membranes because the cavitation activities and formation of free radicals. For this purpose, this study aimed to evaluate the effect of different times of contact of ultrasound (40 kHz, 200 W for 1, 5 and 10 min) on quality parameters (browning, firmness and total starch content) of fresh-cut potatoes during the product shelf life (12 days; 3 ± 1 C) and cell microstructure. Ultrasound was applied to asterix strips (rectangular, 10 9 10 mm). Results showed that the time of sonication and storage affected significantly to the pH of the samples. Treated samples for 5 and 10 min presented the lower values of pH. No color degradation was noticed immediately after the application of treatments (Hue and Chroma). However, a slight decrease in Hue angle of fresh-cut potatoes during storage has been observed. The use of 5 min of sonication inhibited 50 % of polyphenol oxidase (PPO) activity for the first 4 days of storage. Samples submitted to 5 and 10 min of ultrasound also had maintained more uniform firmness after frying during storage time. However, the longest time of immersion (10 min) caused damage in the potato cells.

Osmotic Treatment (OT) enables to introduce controlled quantities of solution solutes into food and partially dehydrate it. The main aim of this study was to formulate intermediate-moisture solid foods with functional ingredients such as grape phenolics using OT. We evaluated how the source of phenolics and different types of binary mixtures of osmo-active solutes, affects: (i) the penetration level of grape phenolics, (ii) the intake of low-molecular- weight phenolics, and (iii) antioxidant capacity in a model food made of agar during OT. Fickian and empirical models were applied to characterise the mass transfer rate of grape phenolics during OT. Finally, the extent and rate of phenolic infusion into plant tissue (apple, banana and potato) was determined while their stability after a post- treatment such as convective air drying was evaluated. Our results confirm that OT is a suitable technology for the exploitation of solid foods into which functional ingredients can be successfully incorporated. Under the conditions that maximized the phenolic infusion, the total phenolic content of the osmo-dehydrated food was close to the values reported in some rich-in-phenolic fruits and vegetables, while the TEAC was three times that of fresh fruit with the highest antioxidant capacity. The effective diffusion coefficients of total and individual phenolics showed that the kind and the concentration of osmo-active solute in the osmotic solution, food structure and the molecular weight of grape phenolics controlled their rate of infusion in the food. OT as a pre-treatment protected against grape phenolic degradation during further convective air drying.

The aim of our work was to supplement a solid foodstuff with grape phenolics by osmotic treatment with an aqueous solution made of osmo-active agents (NaCl and sucrose) and a commercial grape seed extract. To investigate how the composition of the osmotic solution affected phenolic infusion, experimental conditions were set by a central composite design with two factors (the molality of NaCl and sucrose in the osmotic solution). In all experiments, the total phenolic content in the osmotic solution was kept constant (6300 +/- 45 mg gallic acid equivalents/kg), and the model food (an agar-agar gel) was processed for 8 h. Throughout the response surface, the osmo-treated model food was significantly supplemented with flavan-3-ols. At the central point of the experimental design, flavan-3-ol monomers and dimers were found in concentrations of 1334 +/- 126 and 486 +/- 55 mg/kg, respectively. Their penetration into the model food was limited by sucrose to a different extent. The Trolox equivalent antioxidant capacity of the osmo-treated gel was higher than that of fruits with a very high free radical scavenging activity.

Osmotic dehydration was assessed as an operation for supplementing a solid foodstuff (a gel was used as the model food) with grape phenolics from a concentrated red grape must to increase its antioxidant properties. The model food was processed for up to 24 h, and the osmotic pressure was adjusted by diluting the concentrated red grape must. In all conditions tested, low molecular weight phenolics (or=610 g/mol) and, in particular, trans-caftaric acid, trans-coutaric acid, ferulic acid, coumaric acid, caffeic acid (hydroxycinnamic acids), gallic acid (hydroxybenzoic acids), quercetin, and rutin (flavonols), were quantified in the red grape must and also in the osmo-dehydrated food. Other flavonoids such as (+)-catechin and (-)epicatechin (flavan-3-ols) were detected only in the red grape must. Trolox equivalent antioxidant activity (TEAC) and ferric reducing antioxidant power (FRAP) were determined in the osmo-dehydrated food. Under the conditions that maximized phenolic infusion, the total phenolic content of the gel was close to the values reported in some rich-in-phenolic fruits and vegetables, whereas TEAC was 3 times that of fresh fruit with the highest antioxidant capacity. Regression analysis showed that the individual phenolics analyzed significantly explain the antioxidant capacity of the osmo-dehydrated food.

Pear juice obtained from pear concentrate was fermented at room temperature using Saccharomyces cerevisiae (BDX, ENOFERM, France) as the fermentation microorganism. During the fermentation process, total sugars were measured. High performance liquid chromatography analyses were used to monitor the fermentation process and to characterize the pear wine. The pear wine obtained was distilled with its lees using three different equipments: a glass alembic (a glass pot still coupled to a glass column), a copper alembic, and a glass alembic with the addition of 5 g/L of copper shavings to the pot still. The same distillations were repeated with the wine without its lees (separated by decanting). Several distillation fractions were collected, up to a total of 500 mL of distillate. Gas chromatography was used to identify and quantify the volatile compounds in each fraction, and the methanol and ethanol contents. Based on these results, the heart fraction was defined. ANOVA tests were performed on the heart fractions to determine quantitative differences between some volatile compounds depending on the equipment used and the presence or absence of the wine lees. From this series of ANOVA tests, it can be concluded that the concentrations of the compounds that are considered to have a negative effect on the quality of the distillates (methanol, ethyl acetate, furfural) decrease or do not change when they are distilled in the presence of lees and in the copper alembic. In addition, the concentrations of the positive compounds (ethyl decanoate and ethyl-2-trans-4-cis-decadienoate) increase in the presence of lees for all of the equipment tested. So, it can be assumed that the distillation of pear wine with its lees in copper alembic leads to a better quality product.

Fresh-cut potato (Solanum tuberosum L.) is a product widely consumed, but the susceptibility of this tube.r to browning is a drawback and limiting factor for its shelf life. This study aimed to evaluate the predisposition of different potato cultivars for being minimally processed, the effect of citric acid in inhibiting browning and the quality of the fried potato during the product shelf-life.

In this work, a comparative study between Aloe vera, chitosan (formulated with acetic (-AC) or citric acid (-C)) and sodium alginate edible coatings was conducted to evaluate the effects on the quality and shelf life of minimally processed kiwifruit. The pH, soluble solids content, titratable acidity, ascorbic acid, color, texture properties, gas concentrations, pectin content, microbial load and sensory quality of the fruit were analyzed during 12 days at 4 ± 1 °C. Chitosan-AC and alginate based coatings act as a gas barrier, although after eight days of storage, a sharp rise in CO 2 production was detected for the alginate and chitosan-C coatings. Aloe vera coating maintained the firmness of the fruit, prevented the ascorbic acid losses and yellowing due to ripening. Aloe vera and chitosan-AC reduced microbial proliferation; however chitosan-AC coated slices were not accepted by the sensory panelists. In contrast, fruit treated with an alginate based coating had higher microorganism counts than the control samples. The sensory panel preferred the kiwifruit slices treated with Aloe vera or chitosan-C coatings compared to the other coatings. Our study indicates that Aloe vera was the best coating to both extend the postharvest shelf life and maintain the sensory properties of the product trough the storage period.