Encapsulation is a process by which small particles of core products are packaged within a wall material to form microcapsules. One common technique to produce encapsulated products is spray-drying which involves the conversion of liquid oils in the form of an emulsion into dry powders. Emulsification conditions, wall components, and spray-drying parameters have been optimized for the microencapsulation of different extra-virgin olive oils. To achieve this goal, the influences of emulsion conditions have been evaluated for different wall components such as proteins (sodium caseinate and gelatin), hydrocolloids (Arabic gum), and hydrolyzed starches (starch, lactose, and maltodextrin). In addition, for each of the tested conditions the ratio of wall solid-to-oil and spraydrying parameters were as well optimized.The microencapsulation effectiveness was determined based on process yield and the ratio between free and encapsulated oil (microencapsulation efficiency). Highest encapsulation yields were achieved when gelatin, Arabic gum and maltodextrin and sodium caseinate and maltodextrin were used as encapsulation agents and the ratio of wall solid-to-oil was 1:4 and 1:2, respectively. Under these conditions, 53% of oil was encapsulated. The influence of olive oil quality in the microencapsulation process was evaluated in terms of fatty acids profile alteration after the microencapsulation process.

The encapsulation is a process by which small particles of core products are packaged within a wall material to form microcapsules. One of the most useful processes for drying thermosensitive substances that are unstable in aqueous solutions is the freeze-drying technique (lyophilization), which involves conversion of liquid oils in the form of an emulsion into dry powders. In this paper, the chemical composition of walnut oil and microencapsulation conditions (microcapsule wall material composition) have been evaluated in order to assess the influence of the microencapsulation process on the quality and shelf-life of microencapsulated walnut oil. Highest encapsulation yield was achieved when maltodextrin, carboxymethylcellulose, and lecithin were used as encapsulation agents and the ratio of oil-wall material was 1:1.5. Under these conditions all the oil was encapsulated. The presence of protein constituents in the microcapsule wall material extended the shelf-life of the microencapsulated walnut oil regardless of the use of antioxidant additives.

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The global expansion of quinoa (Chenopodium quinoa Willd.) cultivation has been related to the nutritional properties of its seeds and the ability of this crop to cope with stress. However, research works evaluating the agronomic impact of quinoa cultivation out of the Andean region are still limited, especially under Mediterranean field conditions. In this work, the agronomic performance, seed composition and nutrient uptake (NU) of five quinoa varieties were analysed in two consecutive years (2017)(2018) under field conditions in Southwestern Europe. High temperatures were recorded during 2017 growing season, resulting in significantly lower yields (1.6 t/ha) compared to 2018 (2.5 t/ha). High-temperature stress coincided with flowering stage in those medium-to-long cycle varieties and was well correlated with detrimental effects on the vegetative stage of short and medium cycle varieties. Seed composition and mineral content of quinoa varied among varieties subjected to heat stress, which could be due to differences in the stress response. Protein and fibre contents were higher under high temperatures, while fats and carbohydrates contents decreased.Nutrient uptake, utilisation and partitioning were reduced under heat stress, probably due to heat-protection mechanisms and associated biochemical changes. Early maturing varieties showed better adaptation, especially Marisma, which achieved the highest yield in both years (3.0 t/ha, on average). Overall, the results here presented support to the potential of quinoa cultivation in Europe highlighting the necessity to further explore varieties better adapted to elevated temperatures, a common stress affecting the Mediterranean area.

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The nutritional quality of quinoa is often related to the high protein content of their seeds. However, and despite not being an oilseed crop, the oil composition of quinoa seeds is remarkable due to its profile, which shows a high proportion of polyunsaturated fatty acids (PUFAs), particularly in essential fatty acids such as linoleic (ω-6) and α-linolenic (ω-3). In line with this, this study aimed at evaluating the effect of elevated temperatures on the oil composition of different quinoa cultivars grown in the field in two consecutive years (i.e., 2017 and 2018). In 2017, heat stress episodes resulted in a reduced oil content and lower quality linked to decreased ratios of oleic acid:linoleic acid, larger omega-6 (ω-6) to omega-3 (ω-3) ratios, and lower monounsaturated fatty acid (MUFA) and higher PUFA contents. Furthermore, the correlations found between mineral nutrients such as phosphorous (P) and the contents of oleic and linoleic acids emphasize the possibility of optimizing oil quality by controlling fertilization. Overall, the results presented in this study show how the environmental and genetic factors and their interaction may impact oil quality in quinoa seeds.

Exploiting the relationship between the nutritional properties of seeds and the genetic background constitutes an essential analysis, which contributes to broadening our knowledge regarding the control of the nutritional quality of seeds or any other edible plant structure. This is an important aspect when aiming at improving the nutritional characteristics of crops, including those of Chenopodium quinoa Willd. (quinoa), which has the potential to contribute to food security worldwide. Previous works have already described changes in the nutritional properties of quinoa seeds due to the influence of the environment, the genotype, or their interaction. However, there is an important limitation in the analyses carried out, including the outcomes that can be translated into agronomical practices and their effect on seed quality. In the present study, several seed nutritional-related parameters were analyzed in 15 quinoa cultivars grown in a particular environmental context. Important agronomical and nutritional differences were found among cultivars, such as variations in mineral or protein contents and seed viability. More importantly, our analyses revealed key correlations between seed quality-related traits in some cultivars, including those that relate yield and antioxidants or yield and the germination rate. These results highlight the importance of considering the genotypic variation in quinoa when selecting improved quinoa varieties with the best nutritional characteristics for new cultivation environments.

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