Comparative evaluation of physicochemical profile and bioactive properties of red edible seaweed Chondrus crispus subjected to different drying methods

Microwave-assisted extraction of Ulva spp. including a stage of selective coagulation of ulvan stimulated by a bio-ionic liquid

Microwave-assisted hydrothermal processing was proposed to recover high valuable compounds with antioxidant and gelling features from Ulva spp. green seaweed. The influence of the extraction conditions on the solubles, ulvan fraction and residual solid phase was studied to achieve a global valorization of the seaweed. A particular emphasis was placed on the selective coagulation of ulvan stimulated by a bio-ionic liquid during the extraction process. The achieved outcomes indicated that the selected microwave treatment exhibited a notable impact on the phytochemical properties of the soluble extracts, with the highest values of sulfate and protein content at 160 °C, and the highest antioxidant features at 200 °C. The most prominent molecular weight distributions were also identified for systems hydrothermal treated at 160 °C. The ulvan analyses showed that those extracted after microwave treatment at 160 °C showed the highest yields, molecular weight and the strongest gel features from the rheological point of view. The presence of the chloride chlorine during the extraction process favored the ulvan performance and the enhancement of the corresponding viscoelastic properties.

Physicochemical Evaluation of Personal Care Products Developed with Chondrus crispus Fractions Processed by Ecofriendly Methodologies

Novel personal care products are necessary to cope with the growing market demand for sustainable green products. In this context, this work deals with the formulation and fundamental physicochemical and rheological characterization of different natural personal care products using bioactive fractions from Chondrus crispus red macroalgae extracted under optimized green conditions. Body milks, body oils and shampoos were supplemented with soluble extracts with antioxidant features recovered after hydrothermal (200 °C) and microwave (170 °C)- and ultrasound (80 °C)-assisted extraction of the red macroalgae used as raw material. Formulated products were also compared with those prepared using (±)-α-tocopherol and butylhydroxytoluene standards. Body scrubs were formulated with the remaining solids (<2.25%) after microwave hydrodiffusion and gravidity treatment of the macroalgae. Results indicated that selected extracts provided personal care products with similar or even better physicochemical, color and viscous features than those supplemented with (±)-α-tocopherol or butylhydroxytoluene commercial antioxidants. Rheological profiles indicated that it is possible to develop personal care products with adequate viscous behavior (102−105 mPa s, at 1 s−1), comparable with their synthetic counterparts. To conclude, the addition of antioxidant extracts led to lower apparent viscosity values suggesting an advantage from the skin applicability point of view, jointly with the absence of both the hysteresis phenomenon and water syneresis of the proposed formulations.

Designing Nutritious and Sustainable Biscuits Using Upcycled Fibre-Rich Ingredients Obtained by Hot Air - Microwave Drying of Orange by-Products

Circular use of resources implies developing mild processes to transform food by-products into value-added products, without using organic solvents or extensive washing and drying steps. Refined ingredients are commonly used in gluten-free bakery resulting in high levels of saturated fatty acids and sugars as well as a lack of essential nutrients like dietary fibres. The objective of this study was (i) to compare the nutritional composition and the water retention capacity (WRC) of an upcycled orange fibre dried by hot air combined with microwave (HAD+MW) and a commercial orange fibre obtained by different methods (COM), and (ii) to compare the nutritional, texture and sensory profile of gluten-free biscuits formulated with HAD+MW and with COM fibres. The total dietary fibre content (72.0 ± 3.0%) and WRC (21.1 ± 2.7 g_water/ g) of HAD+MW fibre did not differ from the nutritional composition of the control orange fibre (COM). However, for HAD+MW fibre, protein (+2.34 fold), fat (-4.75 fold), ash (-2.31 fold), sugars (-1.42 fold) and moisture content (+11.5 fold) was different from COM. Instrumental texture analysis showed that biscuits with HAD+MW fiber resulted in less hardness (26%) than those with COM fiber. However, this difference was not perceived by panellists (p > 0.05). Exterior colour, cereal, vanilla and citrus aroma-flavour, and granularity were slightly more intense in HAD+MW biscuits but still similar to the commercial control fiber. Thus, the HAD+MW drying method can be used for upcycling orange by-products, obtaining less refined and more nutritious and sustainable ingredients for fiber-enrichment of gluten-free biscuits.