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Edible insects are being considered as a sustainable source of protein and are continuously appearing in markets in the West. The impact of COVID-19 on the willingness to consume (WTC) two products enriched with insect ingredients, jam and yogurt, was analyzed. A semistructured questionnaire was applied using the Qualtrics© consumer panel. Data was collected from 799 and 481 consumers before and during the COVID-19 lockdown in Catalonia (Spain), respectively. The multinomial logit (MNL) model was used to analyze the determinant factors affecting consumers’ WTC insect-based products and the impact of COVID-19 on such heterogeneity. Results showed that the outbreak of COVID-19 caused a significant decrease in the WTC. Findings also revealed that consumers who contracted the COVID-19, strictly followed the regulations during the confinement, and are well informed about symptoms were more likely to reject the consumption of the insect-based products. Both before and during the lockdown, results showed that young and employed consumers, with low-income level, who give importance to the environmental attribute in food are prone to consume insect-based food products. The COVID-19 outbreak had a homogenizing impact on consumers’ WTC with respect to the gender variable. Consumers’ affirmation towards strict food safety standards of the insect-based products should be remarked.

© 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.

Food fortification has been used for many years to combat micronutrient deficiencies; the main challenge with food fortification is the combination of a bioavailable, affordable fortificant with the best (food) vehicle as a carrier to reach at-risk populations. This paper considers mineral deficiencies, especially iron, food fortification, target populations, and the use of chelates in food fortification, as well as different types of mineral-chelate complexes, advantages and limitations of previous trials, methods used for analysis of these complexes, bioavailability of minerals, factors influencing it, and methods particularly those in vitro for predicting outcomes. Three innovative methods (encapsulation, nanoparticulation, and chelation) were explored, which aim to overcome problems associated with conventional fortification, especially those affecting organoleptic properties and bioavailability; but often lead to the emergence of new limitations (for example instability, impracticality and high costs) requiring further research.

Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques were used to study the effect of four food additives, agar, alginate, lecithin and glycerol, at three different concentrations, 0.5, 1 and 1.5%, on the molecular structure of potato puree prepared from commercial potato powder. Vibrational spectra revealed that the amylose-amylopectin skeleton present in the raw potato starch was missing in the potato powder but could be fully recovered upon water addition when the potato puree was prepared. FTIR peaks corresponding to water were clearly present in the potato powder, indicating the important structural role of water molecules in the recovery of the initial molecular conformation. None of the studied puree samples presented a crystalline structure or strong internal order. A comparison of the FTIR and XRD results revealed that the additives exerted some effects, mainly on the long-range order of the starch structure via interacting with and changing -OH and hydrogen bond interactions.

Background Digitalizing food using 3-Dimensional (3D) printing is an incipient sector that has a great potential of producing customized food with complex geometries, tailored texture and nutritional content. Yet, its application is still limited and the process utility is under the investigation of many researchers. Scope and approach The main objective of this review was to analyze and compare published articles pertaining 3D food printing to ensure how to reach compatibility between the huge varieties of food ingredients and their corresponding best printing parameters. Different from previously published reviews in the same journal by Lipton et al. (2015) and Liu et al. (2017), this review focuses in depth on optimizing extrusion based food printing which supports the widest array of food and maintains numerous shapes and textures. The benefits and limitations of 3D food printing were critically reviewed from a different perspective while providing ample mechanisms to overcome those barriers. Key findings and conclusions Four main obstacles hamper the printing process: ordinance and guidelines, food shelf life, ingredients restrictions and post processing. Unity and integrity between material properties and process parameters is the key for a best end product. For each group, specific criteria should be monitored: rheological, textural, physiochemical and sensorial properties of the material its self in accordance with the process parameters of nozzle diameter, nozzle height, printing speeds and temperature of printing. It is hoped that this paper will unlock further research on investigating a wider range of food printing ingredients and their influence on customer acceptability.

The aim of this study was to evaluate the effect of three Lebanese wild plant extracts on acrylamide (AA) content in French fries, and to investigate the impact of air frying (AF) and deep frying (DF) techniques against AA formation. HPLC showed higher level of AA in DF (1384.79 ng/g) than in AF (163.1 ng/g). Indeed, the plant extracts of ginger, borage and fennel succeeded to decrease AA (59.67, 67.99, and 73.36% in (AF) and 21.91, 66.29 and 29.15% in (DF) respectively) in both fryers. Accordingly, borage fennel and ginger with their high scavenging activity (86.09%, 89.11% 93.67% respectively) and total phenolic contents (298.61, 117.79 and 97.36 of GAE respectively) can act as healthy beneficial pre-treatment, overall reducing AA in potato fries particularly in AF. This study was the first to reveal the importance of using plant extract in reducing AA in potato fries, a staple Lebanese food.

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.

This paper studies the applicability of extrusion-based 3D printing for constructing novel shapes from potato puree and the effects of four additives (agar, alginate, lecithin, and glycerol) added separately at three concentrations (0.5, 1, 1.5%) on the internal strength, mechanical properties, microstructure, and color of potato puree. The printability of the potato puree and the mixtures was assayed by examining the consistency of the extrusions and the stability and accuracy of the printed patterns. The results indicate that better printing was achieved at a nozzle height of 0.5 cm and a nozzle diameter of 4 mm, with concentrations of alginate and agar between 0.5–1.5% and 0.5–1%, respectively, providing the best printability and end product stability, which was attributed to their respective high mechanical characteristics and specific mechanical energy (SME) values. Scanning electron microscopy (SEM) revealed that more convolutions were induced in the potato puree upon the addition of agar or alginate, which increased the puree stability. 3D printing did not significantly affect the surface color parameters of the final product. This study showed that the 3D printing process is a critical factor for initializing the production of customized healthy products.

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.

The effects of agar, alginate, lecithin and glycerol on the rheological properties of commercial potato puree were investigated and interpreted in terms of starch microstructural changes, and the applicability of the Cox-Merz rule was evaluated. Each additive was applied separately at two concentrations (0.5 and 1%). Microscopic observations revealed more swollen starch aggregations in lecithin and glycerol compared with those of potato puree and agar, consequently affecting the rheological properties of potato puree. All samples exhibited shear thinning non-Newtonian behaviour. Rheological measurements were strongly concentration dependent. At 0.5% concentration, additives exerted decreases in all the rheological properties of potato puree in the order of glycerol > alginate > lecithin > agar, while at 1% concentration, the order changed to glycerol > lecithin > alginate, whereas 1% agar behaved differently, increasing all rheological values. This study also showed that agar and alginate in addition to potato puree could be valuable and advantageous for further technological processes, such as 3D printing.

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.

In the northeast of Spain, the production of large amounts of pig slurry that exceed the fertilization requirements of local field crops is contributing to the deterioration of the soil environment. In recent years, the construction of six treatment facilities has allowed the exportation of nutrient surplus as thermally dried pig slurry (TDPS). Even though it is already used as an amendment, however, little is known about its effect on soil N availability. A long-term aerobic incubation test was used to monitor organic C and apparent N mineralization. After 34 wk, the untreated soil cumulative apparent N mineralization value was 145 mg kg ―1 and the potentially mineralizable N (θ N * ) was 196.6 mg kg ―1 . In soil treated with 1.6 g kg ―1 TDPS, the θ N * increased by 14% in relation to untreated soil. In soil treated with 4.8 g kg ― 1 of TDPS, the θ N * increased by 24%. The similar patterns of the emitted CO 2 -C and the recovered NO 3 ―N in the untreated soil and TDPS-treated soil show that it is unlikely that significant losses of N occur as gaseous N. It was found that when a low N dose was used, the θ N * was 66% of that added, but only 37% was detected when a higher dose was used. This suggests that, in relative terms, at higher doses there is less microbiological activity than at lower doses. Adding 62.8 mg N kg ―1 as (NH 4 ) 2 HPO 4 and (NH 2 ) 2 CO, however, enhanced the mineralization of the soil organic N, providing 20% more N in relation to the untreated soil.

This work analyzes the ability of nanofiltration membranes to separate biogenic amines. Biogenic amines evolve in fermented foods and beverages and may have toxic effects. Model solutions of putrescine, histamine and tyramine in a wide range of pH were tested using an organic membrane with a molecular weight cut-off (MWCO) of 1000 Da and an isoelectric point (IEP) of about 7. Feed pH strongly influenced solute rejection. In acidic conditions up to pH 4, rejections of around 98, 96 and 90% were attained for histamine, putrescine and tyramine, respectively. Very low rejections of 5–10% were found at neutral pH and only moderate 20–40% rejections were generally observed in the alkaline zone. Furthermore, proton rejection was negative up to pH 6 and positive above this pH, regardless of the amine tested. The results were discussed in terms of the changes that pH produces on the electrical charge of both membrane and amines, and consequently on the membrane–solute interactions. Electrostatic repulsion was shown to be the dominant mechanism governing the separation process. In contrast, sieving exclusion did not seem to play a significant role.

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.

Organoleptic qualities are an important factor in the market value of legumes, especially in developed countries. Unfortunately, the molecules that have the greatest influence on the texture of beans undergo important transformations during soaking and cooking. Moreover, the extent to which these changes are linear is unknown, making uncertain the use of raw beans in chemical screenings for sensory properties. Results of our experiments show that the amount of protein and amylose present in raw beans provides a good indicator of these substances in cooked beans (correlation coefficients between raw and cooked beans = 0.91, p ⩽ 0.001 and 0.87, p ⩽ 0.01, respectively). The Mg content in the raw seed coat also shows a strong correlation with that found in the cooked seed coat (r = 0.86, p ⩽ 0.01). The correlations found for the other traits are weaker, indicating that the evaluation of raw samples is not predictive of the findings in cooked beans.

The increase in the consumption of pulses in developed countries is strongly related to the availability of varieties with high-quality sensory attributes. Local varieties show variability of this characteristic but the extent is unknown. This study aims to assess the variability in texture and chemical composition among traditional Spanish varieties of common beans. Texture differences among varieties found by panellists correspond to chemical variation, although chemical differences within varieties seem greater than those reported in sensory analyses. It seems reasonable to screen existing information on the chemical composition of common beans to identify promising varieties to be tested in sensory trials. Nevertheless, selection within varieties should be performed only after sensory tests on the degree of differences shown by extreme genotypes for components such as protein or starch. Copyright © 2006 Society of Chemical Industry

The removal of cadmium ions from aqueous solutions where chitosan was present was carried out by polymer enhanced ultrafiltration (PEUF). The effect of pH and polymer/metal ratio was studied. Essentially, chitosan binds cadmium ions at neutral pH, but the protonation of amine groups leads to the release of Cd2+ when pH is lowered. A two-phase model, previously developed for a soluble ion-exchange applied to water softening, was adapted for complexation reactions. This model considers the feed solution to be divided into two regions. One region is occupied by the polymer, the bounded ions and some water; the other region is the remaining solution. The estimation of two parameters, the equilibrium constants corresponding to the formation of the complexes Cd(RNH2)2+ and Cd(RNH2)22+, allows to calculate cadmium rejections that agree with the experimental ones. The advantage of a two-phase model versus a single-phase one is discussed.

The Ganxet bean (Phaseolus vulgaris L), highly appreciated in Catalan gastronomy, has a higher proportion of seed coat than other beans (eg White Kidney or Faba Asturiana); however, general diners and sensory tests point out a lower perception of this seed coat. The differences in chemical composition between Ganxet, White Kidney and Faba Asturiana beans, before and after cooking, were established and related to perceived sensory differences in seed coat content. Ganxet's higher absolute and percentage losses of total dietary fibre (19.5%), soluble dietary fibre (32.5%), cellulose (25.6%) and pectins (38.1%) break down the consistency of the seed coat during cooking, which would explain its low sensory perception. The high loss of cellulose during cooking could be due to its partial combination with proteins, which would aid its breakdown. © 2002 Society of Chemical Industry

Water softening has been carried out by polymer enhanced ultrafiltration (PEUF). Poly(acrylic acid–maleic anhydride) sodium salt (PAM-Na), a polyelectrolyte containing COO − groups, attracts Ca 2+ and releases Na + ions. When pH is lowered, H + replaces the bound Ca 2+ . Thus, the polyelectrolyte can be regenerated and reused. A model is proposed to explain the observed calcium and sodium rejections at different experimental conditions. The feed solution is considered to be divided into two phases. One phase is occupied by the macro ions and bound counter ions and the other is the remaining solution. The model only needs to determine two equilibrium constants ( K Na,H and K Ca,Na ) which indicate the relative tendencies of Na + versus H + , and Ca 2+ versus Na + to bind the polymer, respectively. K Na,H value was determined by titration and it is pH dependent. K Ca,Na value was calculated from ultrafiltration runs at neutral pH and its value goes well with other ultrafiltration runs when pH is varied.

Micellar-enhanced ultrafiltration (MEUF) of phenol and a cationic surfactant, cetylpyridinium chloride (CPC), is studied using two polysulfone membranes of 5- and 50-kDa molecular weight cutoff (MWCO) and two ceramic membranes of 15- and 50-kDa MWCO. Filtrations are run under laminar cross-flow and steady-state conditions. The effect of operation variables (pressure and retentate flux) and membrane properties (nature and MWCO) on permeate flux, surfactant, and phenol rejections is analyzed. The permeate flux depends, among other variables, on the fouling favored by membrane-micelle interactions, which are strongest in the 50-kDa MWCO ceramic membrane. On the other hand, surfactant rejection is mainly determined by the pore size and influenced by the pressure for both 50-kDa MWCO membranes. An equilibrium distribution constant, K(s), of phenol between surfactant micelles and water is calculated. Its value is not significantly affected by operation conditions and membrane type. K(s) is also approximately 20% lower than the value determined in a previous work with batch dead-end ultrafiltration.

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.

Equilibrium distribution constants, K s , of phenol between surfactant micelles and water have been determined by micellar enhanced ultrafiltration (MEUF) using commercial ultrafiltering centrifuge tubes. Three surfactants: sodium dodecyl sulphate (SDS), polyoxyethylene 20 cetyl ether (C16E20) and cetylpiridinium chloride (CPC) were tested with a 10 000 molecular weight cut off (MWCO) membrane. Additionally, membranes of 5000 and 30 000 MWCO were used for CPC. A phenomenological mathematical model has been proposed for the batch MEUF process and checked with the experimental permeate or retentate composition. The model is based on two assumptions: monomeric molecules are not rejected by the membrane and the rejection of micelles is independent of the retentate concentration. The measured micelles rejections for different surfactants and the equivalent molecular weight of the micelles are correlated and they are not significantly affected by the addition of phenol. The estimates of K s for SDS and CPC agree with previously reported values determined by other methods. K s values for CPC, calculated using 5000, 10 000 and 30 000 MWCO membranes, have not been significantly different. K s estimate has allowed to predict the phenol permeate concentration measured in continuous tangential MEUF experiments.

The Ganxet bean is a landrace that is greatly appreciated in northeast Spain. For commercial purposes a pure line selection process was undertaken in this landrace. Simultaneously, the Ganxet bean was compared with standard controls for nutritional traits. Seven inbred lines, representative of the variability within the Ganxet germplasm, were studied per se and compared with bean varieties White Kidney, Navy, Faba Asturiana and Tolosa. The Ganxet germplasm was found to contain more protein, less total dietary fibre, more digestible dietary fibre, a higher proportion of seedcoat, more glucose and less starch than the controls. Study of the agronomic, commercial, nutritional and gastronomic aspects of the Ganxet inbred lines showed sufficient variability to allow two inbred lines representative of Ganxet germplasm to be chosen for commercialisation.

The chemical composition determines plant-derived foods’ sensory traits; genetic and environmental effects and their interactions determine chemical composition. Understanding the importance of each factor should help characterise foodstuffs according to the variety and place of cultivation. We studied the effects of variety (five landraces + two checks) and environment (five locations and two years) on some molecules important for beans’ ( Phaseolus vulgaris L.) sensory value. The greatest location effects were on protein and starch content and variety effects were due to combinations of traits (mainly sucrose, protein, and malic acid). The variety × location interactions detected in protein, sucrose, citric acid, and malic acid were difficult to associate to the gastronomic success of a particular variety cultivated at a particular location. Our results showed that protected designation of origin (PDO) in beans could be delimited on the basis of chemical composition, derived from the particular environmental characteristics of a region and the genetic characteristics of the varieties admitted.

Ten samples of rabbit manure representative of the different techniques of treatment and handling used by livestock farms in Catalonia have been characterized. Two of the materials with a different composition have been composted. The origin of materials influence the composting processes and the compost final characteristics. It seems to be relationated with the balance between humification and decomposition processes.

The aim of this work has been to determine the effect of sterilized and non-sterilized, acrobically or anaerobically digested sewage sludges on urease and phosphatase activities, on populations of nitrite oxidizers and on some chemical properties in laboratory conditions and for long incubation periods. Both urease an phosphatase activities were affected when anaerobic sludges were added to the soil. The inhibitory effects on both enzyme activities attributed to the presence of heavy metals were probably masked by the additional source of organic matter both with acrobic and anaerobic sludges. The level of the NO 2 − oxidizer populations was higher in the aerobic than in the anaerobic sludge amended soil. Ammonia-N concentration were increased when the soil received sludges reflecting a higher mineralization rate probably due to a stimulation of the indigencous ammonia producing microorganisms since differences between non-sterilized and sterilized treatments were minimal or absent. Nitrate-N concentrations increased in amended soils and care must be taken to restrict as much as possible the downward movement of nitrate in order to minimize ground-water pollution.

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.