Search Results (764)

Unconventional protein sources are currently extensively studied as food ingredients. This study aimed to evaluate the effect of 1.5% and 3% field cricket powder (GB) and 2–8% of its mixture (1:1) with spirulina powder (S) on the nutritional value, physicochemical properties, and sensory characteristics of corn extrudates. Additionally, 2% baking powder (BP) was added to assess its impact on the properties of the enriched extrudates. The results showed that both GB and GB + S improved nutritional value, with protein content increasing by up to 46% and higher levels of essential amino acids, particularly leucine and valine. However, these ingredients decreased the expansion ratio (by up to 15%), colour lightness (by up to 30%), and yellowness (by up to 47%) and increased the hardness (by up to 25%) of the corn extrudates. The S addition positively influenced product storage stability but decreased its sensory acceptance, especially aroma and taste. The BP addition mitigated the negative effects of higher GB and GB + S concentrations, particularly on sensory characteristics. In conclusion, incorporating up to 6% of the GB + S mixture provides a higher protein content with only minor changes to the product’s characteristics compared to GB. Ratings exceeding 4.2 points indicate the good acceptability of these snacks. Full article

This article is focused on the development and characterization of a series of biodegradable and eco-friendly colour masterbatches (MBs), based on natural pigments and biodegradable polylactic acid (PLA) and polybutylene succinate (PBS). Four commercial natural pigments were used, spirulina, curcumin, beetroot and chlorophyllin, to develop the colour masterbatches using a twin-screw extruder. The natural pigment-based MBs were added at 2, 4 and 6 wt%, as additives to study the effect on the properties of injected biodegradable parts (PLA and PBS). The injected samples were characterized in terms of their mechanical (tensile and Charpy impact tests) and visual properties (according to CieLab). In addition, the ageing of the coloured material was followed by colorimetric analysis after its exposure under a Xenon lamp. The mechanical results showed that the addition of coloured masterbatches in different percentages (2–6 wt%) did not significantly change the properties of the materials with respect to the as-received ones. A noticeable colour difference in the injected samples was observed after the first 50 h of artificial light exposure. Regarding environmental concerns, the study showed that the carbon footprint of natural pigments and electricity consumption during extrusion and pelletizing were lower. Full article

During postharvest cold storage, fruit sustains physical and biochemical changes, which may result in physiological rind disorders that consequently affect the fruit’s marketability. Preharvest conditions are known to affect postharvest fruit quality, with the effect of preharvest shade netting being currently unknown. To this end, ‘Nadorcott’ mandarin (Citrus reticulata Blanco) fruit, grown under shade netting and without it, was harvested during two consecutive seasons from an orchard in Citrusdal, Western Cape, South Africa. The fruit was evaluated prior to, as well as after a 7-day shelf-life period following cold storage at either −0.6 or 4 °C for 14, 27 and 34 days, respectively, for changes in rind and pulp colour, rind carotenoids, soluble solid content (SSC), citric acid content and SSC/citric acid ratio. Weight loss and the incidence of rind physiological disorders (staining) were also recorded. The results showed that shade net did not affect the storage behaviour of the fruit, as no treatment differences were seen. However, a storage duration effect for both treatments was evident in some internal and external quality parameters, viz., weight loss percentage and carotenoid content increased over the storage duration. Inconsistency regarding the storage duration effect on the rind colour, SSC and acid content were evident between seasons, at both temperatures. Staining only occurred in the first season after 34 days at both temperatures. The results indicated that shade netting had no negative effect on the cold-storage behaviour of ‘Nadorcott’ fruit. However, contrasting findings from this study emphasized that the condition of the fruit at harvest plays a significant role in the postharvest behaviour of the fruit during cold storage, and different growing conditions may also be a contributable factor. Full article

Thermochromic phase change materials (TPCMs) are gaining increasing interest among scientists. These multifunctional materials can store thermal energy but also, at the same time, during the phase transition, they can change colour. Thermal conductivity is also extremely important for this type of material, which is why various additives are used for this purpose. This work aimed to study the properties of thermochromic phase change materials with an inorganic modifier. Stearic acid, behenyl alcohol, and bromocresol purple were used as thermochromic system components, while boron nitride particles were used as an additive. The key tests for such systems are thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), which allow determining the thermal stability of the materials (at around 170 °C) and phase transition parameters (thermal energy storage of 300 J/g in the range of 40–75 °C). The thermochromic properties were tested, and satisfactory results were obtained. In the end, laser flash analysis (LFA) tests indicated that boron nitride improves the thermal conductivity of the organic thermochromic phase change material by almost 30%. The results showed that the tested materials have great potential as thermochromic phase change materials for thermal energy storage. Full article

A gap exists between consumer adoption of sustainable purchasing habits and the behavioural changes required to significantly decrease planetary environmental impact. Current ecolabels do not enable purchasing based on environmental impact, and an effective labelling scheme is required to change purchasing priorities. Using focus groups, ecolabels with components varying in the depth of environmental information conveyed, visual features employed, as well as product comparability and scalability of design, were evaluated by consumers with differing levels of environmental awareness. Independent, credible information accessible to consumers of varying environmental awareness was a participant priority. In-depth data communicated through a bar or pie chart with an interpretable holistic message across all environmental factors was preferred. Colour-coded components offering product comparisons and scalable to the size of the packaging, product value, and lifetime were most likely to empower environmentally motivated purchasing. Insights can inform the development of an effective ecolabelling scheme that equips consumers to adopt more sustainable purchasing habits. Full article

In modern digital photogrammetry, an image is usually registered via a digital matrix with an array of colour filters. From the registration of the image until feature points are detected on the image, the image is subjected to a series of calculations, i.e., demosaicing and conversion to greyscale, among others. These algorithms respond differently to the varying light spectrum of the scene, which consequently results in the feature location changing. In this study, the effect of scene illumination on the localisation of a feature in an image is presented. The demosaicing and greyscale conversion algorithms that produce the largest and smallest deviation of the feature from the reference point were assessed. Twelve different illumination settings from polychromatic light to monochromatic light were developed and performed, and five different demosaicing algorithms and five different methods of converting a colour image to greyscale were analysed. A total of 300 different cases were examined. As the study shows, the lowest deviation in the polychromatic light domain was achieved for light with a colour temperature of 5600 K and 5000 K, while in the monochromatic light domain, it was achieved for light with a green colour. Demosaicing methods have a significant effect on the localisation of a feature, and so the smallest feature deviation was achieved for smooth hue-type demosaicing, while for greyscale conversion, it was achieved for the mean type. Demosaicing and greyscale conversion methods for monochrome light had no effect. The article discusses the problem and concludes with recommendations and suggestions in the area of illuminating the scene with artificial light and the application of the algorithms, in order to achieve the highest accuracy using photogrammetric methods. Full article

Fruit development and maturation rely on intrinsic genetic programs involving hormone biosynthesis and signalling and environmental cues, integrating phenological cycles and climatic issues encompassing abiotic stresses and climate change. In persimmon trees, environmental inputs strongly influence fitness and agricultural performance, and fruit yield can be severely compromised by them. We have grown two persimmon accessions (‘Rojo Brillante’ and ‘Fuyu’) under contrasting meteorological conditions of two locations in Spain and Japan. Fruit size, colour change, and firmness parameters were followed during fruit development from 30 days after fruit set until commercial ripening, and the expression of genes related to ethylene production and signalling, gibberellin response, carotenoid biosynthesis, cell wall dynamics, and oxidative stress were reported. Genes depending on intrinsic developmental programs (ethylene and ripening variables, mostly) showed common expression trends in both cultivars and locations, whereas gibberellin and abiotic stress-related genes mimicked reduced fruit growth and abiotic stress associated with higher summer temperatures (>35 °C) and lower rainfall reported in the Spanish location. The expression pattern of these genes is consistent with a growth–defence trade-off that explains fruit differential growth through hormonal and stress tolerance mechanisms. Full article

Numerous policies have been proposed by international and supranational institutions, such as the European Union, to surveil Earth from space and furnish indicators of environmental conditions across diverse scenarios. In tandem with these policies, different initiatives, particularly on both sides of the Atlantic, have emerged to provide valuable data for environmental management such as the concept of essential climate variables. However, a key question arises: do the available data align with the monitoring requirements outlined in these policies? In this paper, we concentrate on Earth Observation (EO) optical data applications for environmental monitoring, with a specific emphasis on ocean colour. In a rapidly changing climate, it becomes imperative to consider data requirements for upcoming space missions. We place particular significance on the application of these data when monitoring lakes and marine protected areas (MPAs). These two use cases, albeit very different in nature, underscore the necessity for higher-spatial-resolution imagery to effectively study these vital habitats. Limnological ecosystems, sensitive to ice melting and temperature fluctuations, serve as crucial indicators of a climate in change. Simultaneously, MPAs, although generally small in size, play a crucial role in safeguarding marine biodiversity and supporting sustainable marine resource management. They are increasingly acknowledged as a critical component of global efforts to conserve and manage marine ecosystems, as exemplified by Target 3 of the Kunming–Montreal Global Biodiversity Framework (GBF), which aims to effectively conserve 30% of terrestrial, inland water, coastal, and marine areas by 2030 through protected areas and other conservation measures. In this paper, we analysed different policies concerning EO data and their application to environmental-based monitoring. We also reviewed and analysed the existing relevant literature in order to find gaps that need to be bridged to effectively monitor these habitats in an ecosystem-based approach, making data more accessible, leading to the generation of water quality indicators derived from new high- and very high-resolution satellite monitoring focusing especially on Chlorophyll-a concentrations. Such data are pivotal for comprehending, at small and local scales, how these habitats are responding to climate change and various stressors. Full article

Along the Arctic and sub-Arctic coasts of Alaska, Siberia, north-eastern China, Hokkaido, Scandinavia and Iceland, people have dressed in clothes or worn shoes made of fish skin for millennia. (Within this article, the terms fish skin and fish leather are used to indicate different processes of the same material. Fish skin: Skin indicates the superficial dermis of an animal. Fish skin is referred to as the historical raw material that is tanned following traditional methods such as mechanical, oiling and smoking tanning, using materials such as bark, brain, urine, fish eggs and corn flour. Fish leather is used to refer that the fish skin has passed one or more stages of industrial vegetable or chrome tanning production and is ready to be used to produce leather goods). These items are often decorated with a rich colour palette of natural dyes provided by nature. In this study, minerals and raw materials of plant origin were collected from riverbanks and processed by Arctic seamstresses who operated as designers, biochemists, zoologists, and climatologists simultaneously. During our research, an international team of fashion, tanning and education specialists used local Arctic and sub-Arctic flora from Sweden, Iceland, and Japan to dye fish leather. Several plants were gathered and sampled on a small scale to test the process and determine the colours they generated based on the historical literature and verbal advice from local experts. This paper describes the process and illustrates the historical use of natural dyes by the Arctic groups originally involved in this craft, building on the traditional cultural heritage that has enabled us to develop sustainable dyeing processes. The results are promising and confirm the applicability of these local plants for dyeing fish skins, providing a basis for a range of natural dye colours from local Arctic flora. The aim is to develop a moderate-sized industrial production of fish leather in this colour palette to replace current unsustainable chemical dyeing processes. This project represents an innovation in material design driven by traditional technologies, addressing changes in interactions between humans and with our environment. The results indicate that new materials, processes, and techniques are often the fruitful marriage of fashion and historical research of traditional methods, helping the industry move towards a more sustainable future. Full article

The Illawarra plum (IP) is native to Australia and has been used as a bush food for centuries. With rich phytochemicals and natural pigments, IP has the potential to be an added ingredient to improve the physicochemical properties of food, including yoghurt. This study prepared dried IP powders through vacuum drying (VD) and freeze drying (FD), produced extracts from these dried powders, and fortified them into Greek-style set yoghurt. The changes in colour, pH, titratable acidity (TA), syneresis, total soluble solids (TS), and phytochemicals were measured throughout a chilled storage period of 28 days. The results showed that FD and FD extract could provide a stable, distinct pink colour to yoghurt. IP powders and their extracts improved TS content and, thus, the consistency of yoghurt. Compared to the control, VD, FD, and FD extract of IP did not significantly affect the level of acidity or syneresis after 28 days of chilled storage. Yoghurt fortified with FD and FD extract had the greatest level of phenolics, anthocyanins, and radical scavenging antioxidant activities. This study revealed that IP powders and their extracts can positively improve the physicochemical properties of Greek-style set yoghurt. FD powder is recommended over its extract to fortify this yoghurt, as it can be cost-effectively prepared by freeze drying and then grinding the fresh fruit into powder. Future studies are needed to evaluate other variables in yoghurt preparation, including the concentration of IP and strains of yoghurt culture. Further, the consumer perception of sensory quality and acceptability of yoghurt fortified with FD IP powder should be investigated. Full article

This study aimed to determine the influence of increased temperature on the mass loss, chemical composition, and colour of pine wood because of the lack of such information. The colour was measured on samples of wood, extracted sawdust, holocellulose, and lignin isolated from the extracted sawdust of pine heartwood and sapwood. A wood sample labelled 20 °C was considered as wood with the original composition. Subsequently, we verified the measured values with the proposed mixing colour model. Pine heartwood and sapwood samples were thermally treated at temperatures of 100, 150, 200, 220, 240, and 260 °C for 1, 3, and 5 h. It was found that sapwood degraded faster than heartwood. The thermal treatment of wood increases lignin content and decreases holocellulose content, especially at 260 °C. The maximum extractive content of 3.60% was at 1 h and a temperature of 260 °C for both parts of the wood. Lightness values decreased with increasing temperature and time of treatment. The coordinate a* of heartwood showed a positive slope until one hour of treatment duration and a temperature of 240 °C. Then, it decreased for the subsequent duration of treatment. The same course was shown for the coordinate b* of sapwood at a temperature of 200 °C. The proposed model of mixing colours proved that changes in both parts of a wood-extracted substance, holocellulose, and lignin content, were responsible for the changing colour of extracted wood. Full article

Sweet cherry grown under sustainable management produces highly valuable fruits, whose quality shows important biochemical and morphological changes during ripening. Research was carried out in Iasi (Romania), with the aim to assess the quality characteristics of the sweet cherry fruits of three cultivars (Van, Andreiaș, Margonia), grown in an inner or outer position inside the tree crown, at the pre-ripening or full ripeness phase. In 2022, the colour component a* showed higher values in cv. Van and Andreias red fruits and in an inner position, whereas the components L* and b* at the full ripeness phase were highest in cv. Margonia. The dry matter and total soluble solids contents increased from the pre-ripening to the full ripeness phase and were highest in cv. Van sweet cherry fruits; the DM of fruit from the outer part of crown was higher than that of fruit from the inner part at the pre-ripening phase. The content of phenolics was the highest in cv. Margonia fruits at the pre-ripening stage and in cv. Van at the full ripeness phase and higher in the inner tree crown zones. The cultivar Margonia generally showed the highest vitamin C content in both years and development phases. The yellow fruit cv. Margonia mostly showed the highest values of chlorophyll a and b. The fruit’s content of carotene, lycopene, and anthocyanins was generally the highest in the red fruits of cv. Andreias. The examined sweet cherry cultivars showed a high variability in fruit nutritional quality and proved to be a rich source of bioactive compounds with antioxidant potential. Full article

The maturation of Arabica coffee fruits is influenced by both endogenous and external factors. The stage of fruit maturation affects the chemical composition of the beans, which in turn impacts the quality of the coffee beverage. During maturation, the fruit peel changes colour from green to red (cherry), signalling the optimal harvest time and suggesting high fruit quality. However, the degree of redness can vary, indicating different levels of maturity. This study aimed to explore the variation in soluble sugar accumulation in relation to the redness of coffee fruit tissues. We classified ripe fruits into six ripeness categories based on the intensity of the red colour of the epicarp, measured using a colourimeter. We analysed total soluble sugar, sucrose, and starch in three parts: coat (exocarp + mesocarp), coat juice (obtained by squeezing the coat), and beans. Our findings reveal that the variation in sugar in the endosperm does not correspond to changes in the coat, suggesting separate regulation of sugar accumulation, particularly sucrose, which is crucial for coffee quality. Our data indicate that there is no transfer of sucrose and reducing sugars from the red coat to the bean. Full article

Background: To evaluate colour stability in artificial saliva by mechanically simulating brushing between in-house 3D-printed resin brackets (IH3DBs) and commercially available brackets. Methods: The samples consist of four sets of ten aesthetic brackets each supplied by four different manufacturers: clear Damon, Synovate C, Crystal and in-house 3D printed brackets (IH3DBs). The brackets were immersed in a plastic tank containing artificial saliva maintained at a constant temperature of 37 °C with a 65-minute brushing system. Staining changes at T0 (pre-brushing) and T1 (post-brushing) were measured with a spectrophotometer according to the VITA and Master scale and brightness values. Statistical analysis compared the colour changes with the Wilcoxon test and in case of significance, severity was investigated. The significance level considered was p < 0.05. Results: The IH3DBs shows statistically significant differences for both scales and brightness values. The Damon and the Crystal brackets report a statistically significant difference only for brightness. The Synovate C bracket shows no statistically significant differences. Conclusions: The IH3DB produced chromaticity differences for the VITA and Master scale possibly due to the surface roughness created during the printing process. However, the IH3DBs together with Damon Clear improved brightness, due to the mechanical action of brushing. Full article

Plant-based protein is considered a sustainable protein source and has increased in demand recently. However, products containing plant-based proteins require further modification to achieve the desired functionalities akin to those present in animal protein products. This study aimed to investigate the effects of enzymes as cross-linking reagents on the physicochemical and functional properties of hybrid plant- and animal-based proteins in which lupin and whey proteins were chosen as representatives, respectively. They were hybridised through enzymatic cross-linking using two laccases (laccase R, derived from Rhus vernicifera and laccase T, derived from Trametes versicolor) and transglutaminase (TG). The cross-linking experiments were conducted by mixing aqueous solutions of lupin flour and whey protein concentrate powder in a ratio of 1:1 of protein content under the conditions of pH 7, 40 °C for 20 h and in the presence of laccase T, laccase R, or TG. The cross-linked mixtures were freeze-dried, and the powders obtained were assessed for their cross-linking pattern, colour, charge distribution (ζ-potential), particle size, thermal stability, morphology, solubility, foaming and emulsifying properties, and total amino acid content. The findings showed that cross-linking with laccase R significantly improved the protein solubility, emulsion stability and foaming ability of the mixture, whereas these functionalities were lower in the TG-treated mixture due to extensive cross-linking. Furthermore, the mixture treated with laccase T turned brownish in colour and showed a decrease in total amino acid content which could be due to the enzyme’s oxidative cross-linking mechanism. Also, the occurrence of cross-linking in the lupin and whey mixture was indicated by changes in other investigated parameters such as particle size, ζ-potential, etc., as compared to the control samples. The obtained results suggested that enzymatic cross-linking, depending on the type of enzyme used, could impact the physicochemical and functional properties of hybrid plant- and animal-based proteins, potentially influencing their applications in food. Full article