The development of reuse processes for plant by-products for both animal and human food offers numerous possibilities for quality-of-life improvements that align with a circular economy model. For this reason, we divided this study into two experiments. First, we designed a combined treatment consisting of laccase, ultrasound, and ascorbic acid to hydrolyze rice straw plant fibers and used the resulting feed as the basis for T. molitor diets. Second, we formulated diets with different inclusion levels (0%, 25%, 50%, 75%, and 100%) of rice straw and treated rice straw to assess their impact on larvae growth and diet digestibility. For each treatment, six replicates were employed: four for the growth–performance–digestibility trial and two for complementary uric acid determination tests. The combined laccase enzyme, ultrasound, and ascorbic acid treatment hydrolyzed 13.2% of the vegetable fibers. The diets containing treated rice straw resulted in higher larvae weight and a better feed conversion ratio; however, reaching 100% by-product inclusion values led to similar results between both diets. In conclusion, these treatments improve the potential of low-nutritional-value vegetable by-products as part of a T. molitor diet, opening the possibility of new methodologies for the use of recalcitrant vegetable by-products for insect rearing.

Orange peel is suitable for reuse due to the quantity and variety of bioactive compounds it contains, such as pectins, sugars and hesperidin. This study designed a scheme for reusing orange peel extract (OPE) using membrane technologies. Initially, a 100 kDa ceramic membrane was used to separate the pectins and hesperidine from acids and sugars and obtain a clarified product. In the subsequent stage, two ultrafiltration membranes of 25 and 5 kDa were tested, improving the results in terms of product transmittance and obtaining permeates whose physical–chemical parameters are compatible with those established by the European Fruit Juice Association. These membranes did not achieve complete separation of monosaccharide sugars from disaccharides. Finally, a 200 Da nanofiltration membrane was used, which completely reduced the sucrose and pectin content, concentrating glucose and fructose by 40%, values higher than those obtained with the GR90PP membrane. In addition, calcium and magnesium ions were completely rejected. Color changes in the permeate and concentrate streams could be appreciated due to the high concentration produced when working in batches. The nanofiltration (NF) process obtained lower yields (approximately 30%) compared to ultrafiltration (approximately 85%).

New types of fortified breads have been developed from a new ingredient obtained by a two-step process for olive oil extraction, without external water addition, called high-quality dried olive (HQDO). HQDO is a minimally processed ingredient rich in phenolic compounds with beneficial health properties. HQDO has been incorporated in different percentages (1% HDQO1, 5% HDQO5, 10% HDQO10, and control CON) to study how it affects the properties of bread. The effects on the texture and shelf-life extension of the breads have also been studied. The bread samples were evaluated by a trained panel in descriptive sensorial analysis (1–10 scale). Fortified breads improve their nutraceutical quality by increasing their phenolic content from 0.19 mg GAE g⁻¹ CON to 0.73 mg GAE g⁻¹ at HDQO10 (using the Folin–Ciocalteu method). Antioxidant activity was increased from 1.24 mg AAE g⁻¹ CON to 1.49 mg AAE g⁻¹ HDQO10 (using the DPPH method). In sensory properties, all fortified breads obtained a high punctuation with a rating near to seven or superior. In “Aroma” and “Aftertaste”, the fortified breads obtained superior ratings. Finally, in “Flavour”, except for HQDO10, all of them had values close to eight. HDQO1 and HDQO5 were selected for their equilibrium between nutritional qualities and sensorial evaluation.

Artichoke by-products are rich in bioactive compounds and could be valorized for use as flour. Blanching is a critical pretreatment in the production of flour from artichokes, as it helps preserve bioactive and nutritional compounds before cutting, drying and milling. However, studies on the blanching of artichoke by-products for flour production are scarce in contrast to those studies on edible artichoke parts. In this article, the effect of different blanching treatments (steam or immersion; 3–15 min) on the bioactive compounds (total phenolic content, TPC; total antioxidant capacity, TAC; and inulin) and color quality of flours of artichoke by-products (obtained after cutting, drying and milling of stems and bracts) was studied. Blanching treatments induced increases in TPC, TAC and inulin, although those increments varied greatly depending on the treatment type and artichoke part. In particular, steaming (15 min) induced the highest TPC increment in artichoke hearts and stems (94 and 46%, respectively); TAC increment in hearts, stems and bracts (987, 1107 and 1660%, respectively); and inulin increment in hearts and stems (106 and 14%, respectively). Steaming (3 min) induced the highest inulin increment in bracts (40%). Immersion (15 min) induced the highest TPC increment in bracts (632%). In addition, the short blanching treatment (3 min) was not enough to inactivate browning enzymes with browning index values of 75, 52 and 67, which were similar, or even higher, to control samples (unblanched). In conclusion, steam blanching for 15 and 3 min induced the highest bioactive contents in stems and hearts and inulin and TAC contents in bracts.

New artichoke flours with high nutraceutical value have been developed. Blanching is a critical pre-treatment in the production of flour from artichokes, as it helps preserve bioac-tive and nutritional compounds before cutting, drying and milling. However, studies on the blanching of artichoke by-products for flour production are scarce, in contrast to those studies on edible artichoke parts. In this article, the effect of different blanching treatments (steam or immersion; 3-15 min) on the bioactive compounds (total phenolic content, TPC; total antioxidant capacity, TAC; and inulin) and color quality of flours (obtained after cut-ting, drying and milling) of artichoke by-products (stems and bracts) was studied. Blanching treatments induced increases in TPC, TAC and inulin, although those incre-ments varied greatly depending on the treatment type and artichoke part. In particular, the steaming (15 min) induced the highest TPC increment in hearts and stems (94 and 46%, respectively), TAC increment in hearts, stems and bracts (987, 1107 and 1660%, respec-tively) and inulin increment in hearts and stems (106 and 14%, respectively). Steaming (3 min) induced the highest inulin increment in bracts (40%). Immersion (15 min) induced the highest TPC increment in bracts (632%). In addition, the short blanching treatment (3 min) was not enough to inactivate browning enzymes with browning index values of 75, 52 and 67, which were similar, or even higher, to control samples (unblanched). In con-clusion, steam blanching for 15 and 3 min induced the highest bioactive contents in stems and hearts, and in bracts for inulin and TAC contents.

This study presents a new strategy for the valorization of pepper by‐products. Effects on the convective drying process and quality of pretreatments: pressing with separation of vegetable water (P) and cutting plus pressing (C+P) compared to a control without pretreatments (CTRL) were evaluated and modelled. The objective was to improve process efficiency while preserving the functional quality of the final product. Drying kinetics showed that the C+P pretreatment reduced drying time from 465 min to 335 min, while pressing alone did not significantly affect drying duration. The product obtained exhibited remarkable bioactive properties. TPC values reached in 15.13 ± 0.91^a mg GAE g^‐1 for CTRL samples and remained significantly higher in pretreated samples (12.62 ± 0.42^b mg GAE g^‐1 for P, 12.29 ± 0.64^b mg GAE g^‐1 for C+P), than in commercial paprika (3.91 ± 0.57^c mg GAE g^‐1); TAC values obtained were 93.13 ± 3.04^c mg AAE g^‐1 for CTRL, 97.41 ± 1.01^b mg AAE g^‐1 for P, 97.81 ± 2.09^b mg AAE g^‐1 for C+P, and 112.46 ± 2.20^a mg AAE g^‐1 for commercial. These results demonstrate that pepper by‐products can be successfully transformed into a high‐quality ingredient using simple, scalable pretreatments. Which improves drying efficiency and the production of a functional ingredient with enhanced phenolic and soluble dietary fiber content compared with commercial paprika.