Luis Tortosa-Díaz

Mr. Luis Tortosa-Díaz

orcid

Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 September 2025 in Applied Sciences
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LJLeslie Gisella Jácome-Silva
Leslie Gisella Jácome-Silva
Fulgencio Marin-IniestaFulgencio Marin-Iniesta
Fulgencio Marin-Iniesta
LTLuis Tortosa-Díaz
Luis Tortosa-Díaz
DPDavid Planes-Muñoz
David Planes-Muñoz
RNRUBEN LOPEZ NICOLAS
RUBEN LOPEZ NICOLAS
Sauerkraut (SK) is a fermented food of plant origin recognised for its nutritional properties and health benefits. It is traditionally produced through spontaneous fermentation, carried out by the native microflora of fresh cabbage, which includes Gram-negative bacteria, moulds, yeasts and finally lactic acid bacteria (LAB), responsible for transforming natural sugars into lactic acid. However, spontaneous fermentation can also promote the growth of undesirable microorganisms, leading to risks of sensory or food safety alterations, such as the production of biogenic amines. To prevent these limitations, the use of LAB starter cultures is presented as a promising alternative. This study evaluated the fermentation of cabbage at 18 °C and 25 °C, comparing spontaneous fermentation with controlled fermentations using probiotic cultures (Lactiplantibacillus plantarum 229v and Lacticaseibacillus rhamnosus GG). Due to its nutritional importance, the folate content of different types of SK has been studied. Spontaneous fermentation showed positive results in all studied parameters; however, L. plantarum 229v was the inoculum with the highest and fastest acidifying efficacy, reducing the pH to below 4.0 after 7 days at both temperatures. At 25 °C, L. plantarum 229v achieved LAB counts higher than those of L. rhamnosus GG (7.02 vs. 6.00 log CFU·g−1) and exerted the most effective control over enterobacteria and moulds/yeasts, reaching undetectable values (0 log CFU·g−1) on day 7 under both conditions. Antioxidant activity after 42 days of fermentation was higher at 18 °C with L. rhamnosus GG, which showed the highest values (up to 3.50 mg CE·g−1 FW), followed by L. plantarum 229v and spontaneous fermentation. In terms of total folate content (TFC) retention, spontaneous fermentation was particularly effective at both temperatures after 42 days of fermentation (794.741 µg/100 g TFC at 18 °C and 586.542 µg/100 g TFC at 25 °C). In sensory analysis, spontaneous fermentation, in general acceptance, was rated highest (6.2), followed by L. plantarum 229v (5.5) and L. rhamnosus GG (5.3). Considering all the factors studied, SK fermentation with the probiotic strain L. plantarum 229v has proven to be the most suitable.

7 December 2025 in Foods
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Asuncion Maria HidalgoAsuncion Maria Hidalgo
Asuncion Maria Hidalgo
JLJosé Antonio Macario Legaz
José Antonio Macario Legaz
JMJorge Saura Martínez
Jorge Saura Martínez
LTLuis Tortosa-Díaz
Luis Tortosa-Díaz
RNRUBEN LOPEZ NICOLAS
RUBEN LOPEZ NICOLAS
Fulgencio Marin-IniestaFulgencio Marin-Iniesta
Fulgencio Marin-Iniesta
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%).

30 August 2025 in Molecules
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JMJorge Saura Martínez
Jorge Saura Martínez
LTLuis Tortosa-Díaz
Luis Tortosa-Díaz
FAFrancisco José López Avilés
Francisco José López Avilés
MMMiguel Juárez Marín
Miguel Juárez Marín
Asuncion Maria HidalgoAsuncion Maria Hidalgo
Asuncion Maria Hidalgo
Fulgencio Marin-IniestaFulgencio Marin-Iniesta
Fulgencio Marin-Iniesta
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.

30 October 2025 in Preprints.org
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LTLuis Tortosa-Díaz
Luis Tortosa-Díaz
Ginés Benito Martínez-HernándezGinés Benito Martínez-Hernández
Ginés Benito Martínez-Hernández
FAFrancisco José López Avilés
Francisco José López Avilés
MMMiguel Juárez Marín
Miguel Juárez Marín
JMJorge Saura Martínez
Jorge Saura Martínez
Fulgencio Marin-IniestaFulgencio Marin-Iniesta
Fulgencio Marin-Iniesta
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.

25 November 2025 in Applied Sciences
Verified
Journal Article
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LTLuis Tortosa-Díaz
Luis Tortosa-Díaz
Ginés Benito Martínez-HernándezGinés Benito Martínez-Hernández
Ginés Benito Martínez-Hernández
FAFrancisco José López Avilés
Francisco José López Avilés
MMMiguel Juárez Marín
Miguel Juárez Marín
JMJorge Saura Martínez
Jorge Saura Martínez
Fulgencio Marin-IniestaFulgencio Marin-Iniesta
Fulgencio Marin-Iniesta
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.

3 November 2026 in Preprints.org
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MMMiguel Juárez Marín
Miguel Juárez Marín
LTLuis Tortosa-Díaz
Luis Tortosa-Díaz
FAFrancisco José López Avilés
Francisco José López Avilés
JMJorge Saura Martínez
Jorge Saura Martínez
Ginés Benito Martínez-HernándezGinés Benito Martínez-Hernández
Ginés Benito Martínez-Hernández
Fulgencio Marin-IniestaFulgencio Marin-Iniesta
Fulgencio Marin-Iniesta
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 ± 0.91a mg GAE g‐1 for CTRL samples and remained significantly higher in pretreated samples (12.62 ± 0.42b mg GAE g‐1 for P, 12.29 ± 0.64b mg GAE g‐1 for C+P), than in commercial paprika (3.91 ± 0.57c mg GAE g‐1); TAC values obtained were 93.13 ± 3.04c mg AAE g‐1 for CTRL, 97.41 ± 1.01b mg AAE g‐1 for P, 97.81 ± 2.09b mg AAE g‐1 for C+P, and 112.46 ± 2.20a 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.