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Our aim was to assess the effect of a self-correction spelling tool based on orthographic revision procedures on third-grade children’s orthographic performance. This tool consisted of grids displaying explicit contextual, phonological and morphological rules. Participants were 70 third-grade students, randomly assigned to an experimental (N = 35) and control group (N = 35). A pretest and post-test were performed a week before the training programme and two weeks after the end of it, consisting of a 76-word spelling test that referred to contextual (32 words), phonological (32 words) and morphological (12 words) rules. The experimental training programme was carried out with children in class and consisted of nine sessions in which children had to spell words dictated by an adult, who then underlined their misspellings with a specific colour (a different colour was assigned to each rule) and asked them to self-correct the misspellings using the grid. None of the words present in the pre- and post-test were used in the training programme. The same words were used in the control group, but instead of self-correcting the misspellings, children were shown the correct spelling and had to copy it three times. The post-test results showed that the experimental group decreased significantly the number of misspellings when compared with the control group, with statistically significant differences for each rule. Nevertheless, the morphological misspellings, after the intervention, were superior to the other types of misspellings. These results show the importance of inducing self-correction spelling strategies in educational contexts. Fundação para a Ciência e Tecnologia info:eu-repo/semantics/acceptedVersion

The food industry is constantly challenged to meet consumer demands for new food products that are safe, convenient, affordable, pleasurable and healthy. An understanding of fundamental structure and function relationships of food components is a key to the design of new foods: ingredient formulation and production processes have a major role in commercial food development but their impact on food structure is poorly characterized and their relationship with consumers’ perceptions is often ignored or underestimated.

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Rapeseed meal is a by-product of the oil-producing industry with a currently underestimated application. Two protein isolates, PI2.5–8.5 or PI10.5–2.5, were obtained from industrial rapeseed meal after treatment with an aqueous ethanol solution. The alkaline-extracted proteins were sequentially precipitated by two different modes, from pH 10.5 to 2.5, and vice versa, from 2.5 to 8.5, with a step of 1 pH unit. The preparation approach influenced both the functional and antioxidant properties of the isolates. The PI10.5–2.5 exhibited higher water and oil absorption capacities than PI2.5–8.5, reaching 2.68 g H2O/g sample and 2.36 g oil/g sample, respectively. The emulsion stability of the PI2.5–8.5, evaluated after heating at 80 °C, was either 100% or close to 100% for all pH values studied (from 2 to 10), except for pH 6 where it reached 93.87%. For the PI10.5–2.5, decreases in the emulsion stability were observed at pH 8 (85.71%) and pH 10 (53.15%). In the entire concentration range, the PI10.5–2.5 exhibited a higher scavenging ability on 2,2-diphenyl-1-picryl hydrazyl (DPPH) and hydroxyl radicals than PI2.5–8.5 as evaluated by DPPH and 2-deoxyribose assays, respectively. At the highest concentration studied, 1.0%, the neutralization of DPPH radicals by PI10.5–2 reached half of that exhibited by synthetic antioxidant butylhydroxytoluene (82.65%). At the same concentration, the inhibition of hydroxyl radicals by PI10.5–2 (71.25%) was close to that achieved by mannitol (75.62%), which was used as a positive control. Established antioxidant capacities add value to the protein isolates that can thus be used as both emulsifiers and antioxidants.

Orange peel was dried applying three different processes: convective drying, microwave drying, and freeze-drying. Some physicochemical properties (moisture content, water activity, and color parameters) and phytochemical characteristics (total phenolic compounds and total antioxidant activity) were assessed in fresh and dried samples. Four kinetic models were tested aiming for convenient modeling of the convective drying curves. The Page and Approximation of diffusion models were adequate in data fitting, which was assessed by the magnitude of the adjusted coefficient of determination ((Formula presented.)) and reduced χ2. The moisture content and water activity of peel dried with the three processes were within acceptable levels for safe storage of products. All processes affected peel color. However, the browning index of freeze-dried samples was equivalent to fresh ones, being higher when convective and microwave drying were applied. Higher chroma parameters were obtained in dried samples indicating a more intense color than fresh peel. Freeze-drying enhanced total phenolic compounds and total antioxidant activity of orange peel when compared to convective and microwave drying. Therefore, from a quality point of view this process seems to be the most appropriate to produce dried orange peel. Practical Applications: Dried orange peel transformed in flour, or slices, cubes, or different geometrical features, may be suitable for incorporation as an ingredient in many types of foods such as cakes, biscuits, or bread, enriching their content in phenolic compounds and total antioxidant activity, therefore creating a value-added product. Within the drying conditions used in this study, it was found that the freeze-drying process is preferable when a lighter and more yellow dried orange peel is desired, with improved phytochemical characteristics. On the other hand, when a darker product with color similar to the fresh peel needs to be attained, the microwave drying process should be chosen.

International audience; Mathematical modelling plays an important role in food engineering having various mathematical models tailored for different food topics. However, mathematical models are followed by limited information on their application in food companies. This paper aims to discuss the extent and the conditions surrounding the usage of mathematical models in the context of European food and drinks industry. It investigates the knowledge, nature and current use of modelling approaches in relation to the industry main characteristics. A total of 203 food companies from 12 European countries were included in this research.Results reveal that the country where the company operates, and size of the company, are more important predictors on the usage of mathematical models followed by the type of food sector. The more developed countries are positioned at the higher level of knowledge and use of available models. Similar pattern was observed at the micro level showing that small or medium sized companies exhibit lack of knowledge, resources and limiting usage of models.

UV-C light is a non-thermal technology with potential application in food industries. The objective was to assess UV-C radiation effect (13.44 W/m2) on microbiological decontamination and some quality characteristics of Cantaloupe melon juice, during refrigerated storage. Juice was inoculated with Listeria innocua (non-pathogenic surrogate of L. monocytogenes) and Alicyclobacillus acidoterrestris spores (spoilage indicators) used as indicators of the UV-C treatment efficacy. Total mesophylls and yeasts and molds were also enumerated. Results demonstrated that 5 min of exposure allowed 3.7 ± 0.3 log10 cycles reduction of L. innocua, while for A. acidoterrestris, 20 min were required to decrease 4.7 ± 0.1 log10 cycles. At the end of refrigerated storage for 13 days, UV-C treated juices retained color, total phenolics content and antioxidant activity, and yeast and molds did not grow. Since UV-C process was effective on microbial inactivation and allowed juice quality maintenance, it can be considered as a promising alternative to thermal pasteurization.

Background Carob (Ceratonia siliqua L.) is an evergreen tree that belongs to the Leguminosae family and is typical of the Mediterranean basin. It is well known for its valuable locust bean gum obtained from carob seeds. However, the food industry can obtain different carob products from carob fruit after processing. Carob products are good sources of dietary fibre, sugars, and a range of bioactive compounds such as polyphenols and D-pinitol. Scope and approach Bioactive compounds present in carob fruit and its derived products help control many health problems such as diabetes, heart diseases, and gastrointestinal disorders due to their anti-hyperglycaemic, antioxidant, and anti-inflammatory activities. So, carob products have a great potential to be used as a functional food ingredient. Key findings and conclusions This article focuses on carob characteristics and processing, chemical composition, health benefits, and applications in food formulations to explore the potential of carob in developing a wide variety of health-beneficial food products.

The objective of this research was to evaluate the effect of drying temperature and innovative pre-treatments (i.e., microwave and ultrasound) on “Rocha” pear drying behavior and quality characteristics, such as color, total phenolic content and antioxidant activity. Experiments were carried out with pear slabs subjected to microwaves (2450 MHz, 539 W, 4 min, microwave oven) and ultrasounds (35 kHz, 10 min, in an ultrasonic bath) as well as control samples. The drying process was conducted in a tray dryer at three different temperatures (50, 55 and 60 °C) and a fixed air velocity of 0.75 m/s. Microwave technology resulted in a higher quality deterioration in dried pear samples compared to those of controls and ultrasound pre-treated samples. The combined application of ultrasound pre-treatment and the higher drying temperature of 60 °C was characterized by the lowest color changes (ΔE = 3.86 ± 0.23) and higher preservation of nutritional parameters (total phenolic content, TPC = 345.60 ± 8.99, and antioxidant activity, EC50 = 8.80 ± 0.34). The drying characteristics of pear fruits were also analyzed by taking into account empirical models, with the Page model presenting the best prediction of the drying behavior. In conclusion, ultrasound application is a promising technology to obtain healthy/nutritious dried “Rocha” pear snacks as dietary sources for consumers.

Several scientific studies point fruits as rich sources of antioxidants but mainly focus on their edible part. However, fruits wastes are abundant sources of bioactive compounds and nutrients, which are considered to be health beneficial. The main purpose was to characterise juice, pulp, peel and seeds of Piel de Sapo melon, in terms of several physicochemical characteristics (soluble solids content, titratable acidity, pH, potassium, colour and water activity), some bioactive compounds (total phenolics, vitamin C, chlorophylls and total carotenoids) and total antioxidant activity. Juice, pulp, peel and seeds represent 47, 19, 27 and 5% of melon total weight, respectively. Peel and seeds stood out by their higher concentration of total phenolics compounds and antioxidant activity when compared to edible parts. The highest potassium concentration was found in seeds. Chlorophylls were only detected in peel, while carotenoids were not detected in any part of the melon analysed. Juice and pulp contributed to 69% of vitamin C amount of the whole fruit. However, its concentration in peel was equivalent to the ones observed in juice and pulp. These results pointed out the importance of fruit wastes valorisation and the development of strategies for their re-utilisation.

The production of rapeseed oil leads to generation of large quantities of rapeseed meal as a by-product. To increase the applicability of the rapeseed meal in feed and food industries, the content of antinutrient compounds is often reduced by treatment with ethanol. The aim of the study was to evaluate the influence of ethanol pre-treatment of the rapeseed meal on protein extractability, amino acid composition and fractional profile. The ethanol treatment of the rapeseed meal significantly increased the protein content from 37.4 to 42.3% and reduced the lipid concentration from 1.9 to 1.1%. Approximately 4- and 14-fold reductions of the phenols and glucosinolate contents were achieved respectively. Protein yield, however, was diminished from 26.4 to 23.6%. A stronger decrease of the protein yield, from 47.8 to 26.4%, was caused by processing of the rape seeds to rapeseed meal. The process resulted in the reduction of lysine content, while further ethanol treatment of the rapeseed meal affected more amino acids, both essential (threonine, phenylalanine) and non-essential (alanine, tyrosine, arginine, histidine). Comparative fractional protein profiles of rape seeds, rapeseed meal and ethanol treated rapeseed meal exhibited differences in both composition of the fractions and the relative quantity of the proteins. Data suggested that the treatment of the rapeseed meal with ethanol impacted protein solubility, amino acid composition and protein fractional profile. This knowledge is valuable when ethanol treated rapeseed meal is used either as a protein feed additive or as a source for generation of protein-rich ingredients with specific nutritive value and functionality.

The author E. M. Gonçalves gratefully acknowledges the support of Fundação para a Ciência e Tecnologia through the research units UIDP/04035/2020 (GeoBioTec). The author J. Pinheiro acknowledges financial support to Fundação para a Ciência e a Tecnologia (FCT), through the strategic project UIDB/04292/2020 granted to MARE, and the Integrated Program of SR&TD “SmartBioR—Smart Valorization of Endogenous Marine Biological Resources Under a Changing Climate” (Centro-01-0145-FEDER-000018) co-funded by Centro 2020 program, Portugal 2020, European Union through the European Regional Development Fund. Teresa R.S. Brandão also gratefully acknowledges the Post-Doctoral Grant (SFRH/ BPD/101179/2014) to FCT. This work was also supported by National Funds from FCT through project UID/Multi/50016/2013. In order to improve the overall quality of frozen carrots (Daucus carota L.), the degradation kinetics of several attributes were quantified during frozen storage under isothermal and nonisothermal conditions. The experimental results showed that the analyzed quality parameters were significantly affected by both tested frozen regimes. For both storage conditions, the degradation of color parameters and drip loss followed zero-order kinetics, and the texture was successfully described by a fractional kinetic model. A first-order kinetic model was adequate in describing total vitamin C decay under isothermal storage conditions. The storage temperature effect was adequately modeled by the Arrhenius law. The carrots shelf life under isothermal storage conditions of −18°C, using a threshold of 50% vitamin C content, will be of 118 days. Practical applications: The objective of this work was to evaluate the degradation kinetics of several quality attributes of carrots when subjected to various frozen storage temperature conditions that may occur along the distribution chain. The quality attributes degradation mechanisms are governed by chemical and/or physical changes that need to be systematically evaluated for further incorporation into product and process designs. The achieved results will be an insight to help manufacturers to predict and optimize products quality and determine its shelf life. info:eu-repo/semantics/publishedVersion

Alicyclobacillus acidoterrestris is a spore-forming bacterium, which is responsible for quality degradation of fruit juices. Non-thermal treatments, such as ultraviolet-C radiation (UV-C) and ultrasound (US), are promising methods for microbial inactivation. The main objective was to study the influence of UV-C, ultrasound and combinations of both treatments on A. acidoterrestris spores inactivation in apple juices. A thermal treatment at 95 °C was used as control. Commercial juices artificially inoculated with the bacterium were exposed to the treatments. Results showed that ultrasound had the lowest impact on A. acidoterrestris inactivation. When UV-C radiation was applied, the number of spores decreased drastically after 8 min, being more effective than a 95 °C thermal treatment. In terms of final microbial loads, combination of US and UV-C did not result in synergetic effects. However, inactivation rates of the combined treatments were significantly different from the ones obtained when the treatments were applied individually.

Ultraviolet-C radiation (UV-C) is widely used as an alternative strategy to control microorganism in food products. Alicyclobacillus acidoterrestris is a thermo-acidophilic, non-pathogenic and spore-forming bacterium, able to grow at low pH and high temperatures. It is a concern, particularly in apple juice thermal pasteurization, because it is responsible for quality degradation. The main objective of this work was to study the influence of UV-C radiation treatments with seven different intensities (0.34, 0.86, 2.59, 5.59, 8.45, 11.50 and 13.44 W/m2) on A. acidoterrestris inactivation in apple juices. Treatments were carried out in a camera (75 × 70 × 45 cm3) with four germicidal UV lamps with peak emission at 254 nm. Commercial juices were artificially inoculated with bacterium, with initial loads around 107 CFU/mL and then exposed to UV-C radiation and the treatment impact on microbial loads was assessed throughout exposure times. The UV transmittance at 254 nm of the juice was 58%. Results showed that the log-survival of A. acidoterrestris decreased linearly with treatment time, for all intensities tested. When the most severe intensity was used, the number of spores decreased drastically (around 5-log reduction) after 8 min of treatment. Overall it can be concluded that UV-C radiation is a promising treatment with a drastic impact on the loads of A. acidoterrestris in apple juices, especially when high intensities are used.

This work evaluated the effect of the air-drying temperature and vacuum packaging on quality and nutritional compounds of dehydrated galega kale, previously steam blanched, during 5 months of storage. When compared with the vacuum packaged kale, the packaging without vacuum yielded improved nutritional features, in general. This approach combined with a drying temperature of 40°C resulted in retention percentages of 62, 38, 92, and 48% for vitamin C, total phenolic content, total antioxidant capacity, and chlorophylls, respectively. The acceptance of the dried product by the consumer was assessed through a focus group. The participants classified the product as a practical and convenient alternative to cook healthier dishes. The appearance of dried galega kale was described as being fragile and being with nice smell, natural colour, and flavour similar to the fresh product. In conclusion, the herein presented product was addressed as an innovation with multiple possible applications in several recipes.

The objective of this study was to evaluate the impact of ozone treatment on microbiological decontamination (intrinsic microflora and inoculated Listeria innocua) and some physicochemical characteristics and bioactive compounds of Cantaloupe melon juice, also during refrigerated storage. To determine adequate ozone exposure, the survival curve of L. innocua was previously assessed. A thermal treatment was also performed seeking comparison with ozone treatment impact. After ozone exposure, L. innocua was not detected in juice samples, while thermal pasteurization allowed a reduction of 5.2 ± 0.2 log cycles. Although ozone reduced the intrinsic microflora loads, this reduction was higher for heat-treated samples. Vitamin C was highly retained in ozone-treated juices (68%), when compared with the pasteurized ones (39%). After 13 days of storage, ozone allowed the retention of the most quality parameters analyzed and, therefore, it can be considered as a promising alternative to traditional pasteurization of Cantaloupe melon juice. Practical applications: The actual consumers' demand for high-quality food standards has launched research to alternative and milder nonthermal processes, which have gained increasing attention and importance in the fruit juice industries. Ideally, preservation and/or processing of foods should involve technologies that prevent undesirable microbial survival and minimize quality attributes changes and nutrient losses. Thermal treatments are conventionally used to attain such targets; however, the content and the biological activity of the most health-related compounds are dramatically reduced. In this context, and particularly in the beverages industries, ozone has been exploited due to its potential for inactivating spoilage and pathogenic microorganisms, while being effective in overall quality retention of the products.

A protein isolate (ERPI) was prepared from ethanol-treated rapeseed meal and used as a stabilizing agent in sunflower and rapeseed oil-in-water emulsions. The aim of the current study was to explore the influence of protein and oil concentrations on initial stability of sunflower and rapeseed oil-in-water emulsions by evaluating Gibbs free energy (ΔG) and particle size distribution. The 7-day dynamics of emulsion stability was investigated by turbidity measurement as well. A 3(2) factorial design was applied to assess the significance of oil (5%, 10% and 15% w/w) and ERPI protein (0.25%, 0.5% and 1.0% w/w) addition on stability of the emulsions. The results demonstrated that the increase of oil concentrations from 5 to 15% positively influenced the initial stability of sunflower and rapeseed oil-in-water emulsions. In both oil types, ERPI protein supplementation at all levels resulted in significant differences in the stability of 5% and 10% oil emulsions but did not alter the initial stability of the emulsions prepared with either 15% sunflower or rapeseed oil. With a few exceptions, there was a good agreement between Gibbs free energy data and microstructural profiles of the emulsions. Overall, emulsions with all sunflower oil concentrations and 1.0% ERPI protein exhibited better initial and a 7-day stability dynamics compared to all rapeseed oil-based emulsions. The study demonstrated the potential of ethanol-treated rapeseed meal protein isolate to serve as an emulsifying agent in sunflower and rapeseed oil containing emulsions.

Fresh-cut fruit is an important segment in fruit market due to the increasing demand for healthy/convenient foods. However, processing promotes a decrease in fruits stability with faster physiological and microbiological deteriorations. Food stability is strongly attributed to its molecular dynamics and “water availability”. Understanding changes in water location/mobility is of utmost importance, since water dynamics profoundly influences physic-chemical and microbiological quality of foods. Nuclear magnetic resonance spectroscopy (NMR) is a methodology used to study the food constituents' molecular dynamics. The aim of this study is to use NMR to evaluate changes in water mobility that occurred in fresh-cut pear tissues during storage, by measuring the transverse relaxation time ( T 2 ) parameter. Results showed the existence of three water classes in the cells after processing, with T 2 values of 10 ms, 187 ms and 3s for cellular wall, cytoplasm and vacuole, respectively. Also, the obtained results demonstrated that T 2 was affected by processing and storage. Moreover, a relationship between T 2 , microstructure and the quality parameters was established. T 2, maximum value increased with pear hardness as well as water activity. On the contrary, a decrease in total colour difference (TCD) was found with T 2 . Results demonstrate the usefulness of the application of NMR relaxometry in food studies.

The aim of this study was to develop fruit powders (apple, banana and strawberry) enriched with a probiotic strain (Lactobacillus plantarum 299v). Two methodologies were proposed: (i) drying of the fruit with probiotic culture incorporated (by convection) or (ii) drying of fruit (by convection) and addition of spray-dried probiotic culture. In the first methodology, processing caused a notable reduction in probiotic viable counts in apple, but this reduction was lower during drying of banana and strawberry. A large reduction in viable cells was also recorded during storage. In the second methodology, the survival of L. plantarum 299v was considerably higher during spray-drying, and fruit powders with a microbial content suitable for a probiotic food (108-109 cfu g-1) were obtained. The fruit powders incorporating L. plantarum 299v can be stored at 4 °C or at room temperature, for at least 3 months. This preliminary study demonstrated that fruit powders are good carriers of probiotic cultures, but the techniques used to produce them should be carefully considered. Methodologies used to obtain a fruit powder with Lactobacillus plantarum: (A) drying of the fruit with probiotic culture incorporated (by convection) and (b) drying of fruit (by convection) and addition of spray-dried probiotic culture.

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This work focuses on the use of the Gompertz-inspired model to predict the thermal inactivation behaviour of microorganisms obtained in solid food products, validated for isothermal and non-isothermal conditions. Experiments were carried out in parsley, artificially inoculated with Listeria innocua. For the isothermal conditions tested, the predictive ability of the model was confined. The higher the temperature, the higher deviations observed (i.e. the model underestimates the inactivation behaviour). However, for the non-isothermal condition tested, the model predicted the microbial response accurately.

Freezing vegetables requires pre-treatments to reduce microbial load and destroy enzymes that impair the frozen product quality. So far blanching has been the most effective pre-treatment, preferred by the food industry, despite its severity: heating up to temperatures close to 100 °C for 1-3 min causes sensory and texture changes in most horticultural products. Alternative blanching treatments, using UV-C radiation combined with milder thermal treatments or with thermosonication, may improve the quality of the final frozen vegetables. Zucchini (Cucurbita pepo L.), the vegetable under study, has an availability in fresh restricted to a season, needing therefore to be often frozen to be used throughout the year. In this study, its surface was first inoculated with two vegetable contaminants, Enterococcus faecalis and Deinococcus radiodurans cells, which are resistant, respectively, to high temperatures and to radiation and then submitted to several blanching treatments, single or combined, and the effect on these microorganisms reduction was evaluated. As single treatments, water blanching (the control treatment, as it is the blanching treatment traditionally used) was applied up to 180 s at temperatures ranging from 65 to 90 °C, and UV-irradiation applied in continuous. As combined pre-treatments, water blanching combined with UV-C (continuous or in pulses), and thermosonication (20 kHz at 50% of power) combined with UV-C pulses were also studied. The continuous UV-C radiation incident irradiance was 11 W/m2 up to 180 s, and the pulses at incident radiance of 67 W/m2, lasting 3.5 s each (35 pulses). Mathematical modeling of bacterial reduction data was carried out using the Bigelow, the Weibull and Weibull modified models, and estimation of their respective kinetic parameters proved that the latter models presented a better fit below 75 °C. The best results proved to be the combination of water blanching at temperatures as low as 85 °C during

The use of the rapeseed meal as a source for preparation of protein-rich ingredients for the food industry is an alternative to the current limited application as a feed additive. The aim of this study was to evaluate foaming properties of an acid-soluble protein-rich ingredient (ASP) obtained from industrial rapeseed meal as a co-product of a protein isolate. Foam capacity and stability over a period of 60 min were evaluated by using volumetric and image analyzing methods. The influence of NaCl at two boundary concentrations (0.03 and 0.25 M) was studied over a pH range from 2 to 10. The ASP exhibited high foamability (> 90%), not influenced by pH or salt addition. In contrast, foam stability, measured over a 60 min period, was pH and NaCl dependent. By the end of the observation period, the addition of 0.25 M NaCl reduced the foam volume by more than 70% at all pH values. After 30 min at pH values 4, 6 and 8, which are the most common for food products, the foams without NaCl retained 51, 38 and 41% of the initial foam volume, respectively. The results were in agreement with image analysis observations where microstructure of the foams with NaCl was more heterogeneous than that of the foams without salt addition. The high foamability and relatively high foam stability at pH from 4 to 8 without NaCl addition shows that ASP could be a potential alternative to plant proteins currently used as foaming agents in the food industry. This is a post-peer-review, pre-copyedit version of an article published in [Journal of food science and technology] Locked until 9.8.2019 due to copyright restrictions. The final authenticated version is available online at: https://doi.org/10.1007/s13197-018-3311-y

Although it is known that fruit products are rich sources of natural bioactive compounds, information on the nutritional value of their waste parts is scarce. The objective was to characterize the edible (juice and pulp) and waste (peel and seeds) parts of Cantaloupe melon (Cucumis melon L. var. reticulatus) in terms of some physicochemical characteristics, bioactive compounds and total antioxidant activity. Juice, pulp, peel and seeds represent 42, 23, 25 and 7% of total weight, respectively. Juice and pulp presented identical profiles in terms of physicochemical characteristics, bioactive compounds and antioxidant activity. They contributed to the majority of the overall content of carotenoids (80%) and vitamin C (84%) in Cantaloupe. Peel and seeds had the highest concentrations of potassium, being seeds the richest portion (7.08 ± 0.16 mg/g). Seeds had also the significantly highest total phenolics concentration (229.13 ± 20.92 µg/g), antioxidant activity (653.67 ± 169.20 µg/g), and soluble solids content (11.79 ± 0.90 °Brix). Peel stood out by the presence of chlorophylls. Since waste parts of Cantaloupe melon represent around 32% of total weight, their valorization is a challenge and strategies to improve ways of re-using them should be developed.

Melon seeds are an important source of bioactive compounds, which are considered to be health beneficial. Therefore, the objective of this work was to assess the impact of gaseous ozone treatments (30 and 60 min) on melon seeds paste (nonedible part) and compare with the effect on pulp (edible part). Ozone treatments were evaluated in terms of physicochemical (color, pH, and soluble solids content) and nutritional profiles (total phenolics, total carotenoids, and total antioxidant capacity) of processed material. Results indicate that ozone has a different impact on the two fruit matrices, being seeds less affected by this preservation treatment.

Ozone treatment is a non-thermal technology with promising applications in food processing. The objective of this study was to evaluate the effect of gaseous ozone at a concentration of 7.0 ± 2.4 g/L for 30 and 60 min of exposure, on some physicochemical characteristics (soluble solids content, pH, titratable acidity and color), bioactive compounds (vitamin C, total phenolics and carotenoids) and total antioxidant activity of Cantaloupe melon juice. The effectiveness of the ozone treatments in microbial survival was also assessed using Alicyclobacillus acidoterrestris spores as target spoilers of the juice (artificially inoculated). Some quality parameters were significantly affected by ozone treatments. The most relevant alterations were observed for color, vitamin C, carotenoids and total antioxidant activity. However, total phenolics content increased significantly in ozonized juices. Even though A. acidoterrestris spores reduced 2.22 ± 0.04 log cycles after 60 min of exposure, other quality related characteristics of the juice were modified. Industrial relevance The actual consumers demand for high-quality food standards have launched research to alternative and milder non-thermal processes, which have gained increasing attention and importance in the fruit juice industries. Ideally, preservation and/or processing of foods should involve technologies that prevent undesirable microbial survival and minimize quality attributes changes and nutrient losses. Thermal treatments are conventionally used to attain such targets, however, the content and the biological activity of the most health-related compounds are dramatically reduced. In this context, and particularly for the beverages industries, ozone has been exploited due to their potential for inactivating spoilage and pathogenic microorganisms while being effective in overall quality retention of the products.

The purpose of this study was to evaluate the drying characteristics and the effects of convective drying temperature on quality attrib0utes of watercress, without any pretreatment. Drying temperatures of 40, 55, and 70 °C resulted in drying times of 230, 119, and 92 min, respectively. The nutritional parameters were negatively correlated with the drying temperature. Retentions of 12.5 ± 3.8−72.8 ± 4.2%, 51.1 ± 3.3−80.4 ± 4.8%, and 44.3 ± 6.1−92.1 ± 12.2% were obtained for vitamin C, total phenolic compounds, and total antioxidant capacity, respectively. Increased values of TCD (total color difference) and BI (browning index), and higher chlorophylls losses (26.1 ± 3.9−55.6 ± 14.9%) were also observed as the drying temperature increased. In conclusion, although longer drying periods are required for lower drying temperatures, these are more profitable in terms of watercress nutritional features and overall quality to the consumer. Practical applications Dehydrated watercress has the potential to be a novel product, for food recipes or food supplements (functional food) due to its high nutritional content. Watercress is rich in nutrients such as vitamin C, minerals and other bioactive compounds, such as phenolics and antioxidants that may decrease cancer incidence. However, fresh watercress leaves are highly perishable with a short shelf life. Drying is one of the oldest processing methods to prolong shelf life of food products by reducing water content, hence decreasing microbial and biochemical activities. Choosing appropriate drying techniques is crucial to prolong watercress shelf-life, increase nutrients and quality retention, and decrease the storage and transportation costs. Dehydrated watercress is convenient to consume without requiring refrigeration or freezing storage, therefore reducing energy costs.

The objective of this work was to evaluate the drying characteristics and the effect of drying temperature on the quality characteristics of Galega kale without any pretreatment. Drying times of 330, 162, 78 and 51 min provided minimal moisture contents, using temperatures of 35, 50, 70 and 85C, respectively. The L* and a* values diminished and b* increased, resulting in increasing values of chroma, total color difference and browning index, as well as decreasing values of the hue angle. A pronounced effect on the retention of total phenolic compounds and vitamin C losses ranging from 4.8 ± 9.7 to 55.5 ± 7.4% were observed. Regarding antioxidant capacity, losses from 51.7 ± 7.5 to 69.6 ± 3.7% were obtained. Chlorophyll a content decreased with increasing drying temperatures, with losses between 8.9 ± 6.7 and 35 ± 5.6%, while degradation of chlorophyll b was negligible. In conclusion, the air drying of Galega kale without any pretreatment resulted in considerable deterioration of its quality characteristics and nutritional value. Practical Applications Drying processes are often applied to preserve and increase the shelf life of vegetables. These products contain an extensive collection of phytochemicals known to provide health benefits. However, these compounds generally undergo significant degradation during drying because of their sensitivity to heat, light, oxygen, as well as to leaching phenomena. Thus, increased attention has been given to the concerns regarding the quality degradation of vegetables during drying. Galega kale was the selected vegetable as information concerning the influence of drying on the quality parameters of this vegetable is scarce. Additionally, this vegetable is known to present several healthy nutrients, but after harvest it is easily perishable. Therefore, drying could be a valuable strategy to preserve and increase the shelf life of this product. Thus, this work evaluates the impact of the drying temperature on the quality properties of Galega kale without the employment of any pretreatment.

Foods are partially crystalline partially amorphous systems. Edible films are considered good models for food systems due to their interesting physical properties, quite straightforward matrices, and easy reproduction. Chitosan is a semicrystalline biopolymer, biocompatible, biodegradable, with antimicrobial activity and filmogenic properties, and it has been thoroughly used in edible films studies. The purpose of this work is to investigate the relationship between the molecular relaxation time in chitosan films, their microstructure (crystallinity) and functional properties. Analyses were carried out using data on chitosan/ glycerol films prepared with different polymer/ plasticisant concentration. In general, results demonstrate that there is a relationship between macroscopic properties and water and glycerol relaxation times. Moreover, results also show that while water is free in the matrix, glycerol is linked to the chitosan polymeric chains, decreasing intermolecular attractions and increasing free volume, thus facilitating molecular migration. Also the data analysis reveals the usefulness of NMR and molecular mobility studies in the matrix for characterisation and development of polymeric structures., Authors Joana F. Fundo and Mafalda A. C. Quintas acknowledge FCT for research grants SFRH/BD/62176/2009 and SFRH/BPD/41715/2007, respectively. The authors acknowledge the Portuguese NMR Network and Strategic Project PEst-C/CTM/LA0025/2013-14 and the support by National Funds from FCT through project PEst-OE/EQB/LA0016/2011.

Physical properties and stability are critical for delivering safe and healthy food to the consumers and thus is a theme that attracts food scientists for a long time. Recently, literature suggests that stability can be fully grasped only if food molecular dynamics and structure are taken into consideration, i.e. an appropriate understanding of the behaviour of food products requires knowledge of its composition, structure and molecular dynamics, through the three-dimensional arrangement of the various structural elements and their interactions. Food systems behaviour is strongly dependent on the water molecular dynamics. Understanding changes in location and mobility of water represents a significant step in food stability knowledge, since water "availability" profoundly influences the chemical, physical and microbiological quality of foods. Nuclear magnetic resonance has been presented as a powerful technique to investigate water dynamics and physical structures of foods through analysis of nuclear magnetisation relaxation times, because it provides information on molecular dynamics of different components in dense complex systems. The application of this technique may be very useful in predicting food systems physicochemical changes, namely texture, viscosity or water migration. This paper aims at reviewing some of the main aspects related to food physical properties and stability, and the role of water in these properties. More specifically, this paper intends to contribute to a deeper understanding of the relationship of molecular constituents-structure-function of food systems, contributing to the development of foods with improved functionality.

Food stability is a critical parameter for both consumers and producers, since it assures safety, nutritional, and sensorial quality of foodstuffs, and at the same time maximizes shelf-life. For a long time, water activity, aw, was considered a determinant parameter in food stability and physical properties. This concept was challenged with the revolutionary approach to the study of food systems using the glass transition concept. Recently, scientific research suggests that molecular mobility is a fundamental approach to fully attain food physical properties and stability. Current literature suggests that stability can only be fully grasped if molecular mobility and structure are taken into consideration; that is, an appropriate understanding of the behavior of food products requires knowledge of its composition, structure, and molecular dynamics, through the three-dimensional arrangement of the various structural elements and their interactions. Food systems are complex mixtures of water, biopolymers, low-molecular weight ingredients, and colloid particles, and the molecular mobility between these different components reflects on the stability of such systems, determining the physical state, microstructure, and composition, which impacts food characteristics. Particularly, food water content, location, and interactions with other components are critical in microbial growth, degradation reactions, and sensorial aspects. Understanding changes in water location and mobility represents a significant step in food stability knowledge, once that water availability profoundly affects chemical, physical, and microbiological quality of foods.

Microbial inactivation often follows a sigmoidal kinetic behaviour, with an initial lag phase, followed by a maximum inactivation rate period and tending to a final asymptotic value. Mathematically, such tendencies may be described by using primary kinetic models (Gompertz based model is one example) that describe microbial survival throughout processing time when stressing conditions are applied. The parameters of kinetic models are directly affected by temperature. Despite the number of mathematical equations used to describe the dependence of the kinetic parameters on temperature (so-called secondary models), there is a lack of studies regarding model comparison and adequacy in data fitting. This work provides a review of mathematical models that describe the temperature dependence of kinetic parameters related to microbial thermal inactivation. Regression analysis schemes and tests seeking model comparison are presented. A case study is included to provide guidance for the assessment of secondary model adequacy and regression analyses procedures. When modelling temperature effects on sigmoidal inactivation kinetics of microorganisms, one should be aware about the regression methodology applied. The most adequate models according to the two-step regression methodology may not be the best selection if a global fit is applied.