Percorrer por autor "Ribeiro, T."
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- Active Packaging Produced by Extrusion with Shrimp Waste: Migration of Astaxanthin into Food SimulantsPublication . Sanches-Silva, A.; Ribeiro, T.; Albuquerque, T.G.; Paseiro, P.; Sendón, R.; Bernaldo de Quirós, A.; López-Cervantes, J.; Sánchez-Machado, D.; Soto Valdez, H.; Angulo, I.; Pardo Aurrekoetxea, G.; Costa, H.S.Introduction: Astaxanthin (3,3’-dihydroxy-β-β´-carotene-4-4´-dione), a potent antioxidant, is one of the major carotenoids in crustaceans. In the frame of the project ‘Preparation of active packaging with antioxidant and antimicrobial activity based on astaxanthin and chitosan’, a methodology for the incorporation of compounds obtained from shrimp waste in plastic matrices was developed to produce an active packaging with antioxidant properties. The aim of the present work was to develop and optimize a method to determine astaxanthin by ultra-high pressure liquid chromatography in fermented shrimp waste. Moreover, the method was also applied to determine the migration of astaxanthin from plastic films containing different amounts of shrimp waste to food simulants. Material and Methods: The method was optimized to determine astaxanthin by ultra-high pressure liquid chromatography (UHPLC) with diode array detection (DAD). The chromatographic separation was achieved using a vanguard pre-column (UPLCÒ BEH, 1.7 µm particle size) and a column (UPLCÒ BEH, 2.1 x 50 mm, 1.7 µm particle size) at 20 °C. The mobile phase was a gradient of A (dichloromethane/methanol with ammonium acetate/acetonitrile 5:20:75 (v/v)) and B (ultrapure water) with a flow rate of 0.5 mL/min. The optimized UPLC method allowed an excellent resolution of astaxanthin. The method was also evaluated in what concerns to validation parameters such as linearity, precision, limit of detection, limit of quantification and recovery. Low density polyethylene plastic films produced by extrusion with different amounts of the lipid fraction of shrimp waste were prepared and tested regarding migration into fatty food stimulants (isooctane and ethanol 95%, v/v). Results and conclusion: The proposed method to determine astaxanthin in shrimp waste is simple and has a low detection level (0.054 μg/mL). The concentration of astaxanthin found in the lipid fraction of fermented shrimp waste was 453.8 μg/g. The films produced by extrusion with the lipid fraction of the fermented shrimp waste did not originate astaxanthin migration into the tested fatty food simulants. Further studies could be made in order to evaluate the capacity of these films in protecting packed food from oxidation.
- Activity of chitosan films against different microorganismsPublication . Sanches-Silva, A.; Maia, C.; Furtado, R.; Ribeiro, T.; Paseiro, P.; Sendón, R.; Rodríguez-Bernaldo de Quirós, A.; López-Cervantes, J.; Sánchez-Machado, D.I.; Bueno, C.; Soto Valdez, H.; Angulo, I.; Aurrekoetxea, G.P.; Bilbao, A.; Costa, H.S.Chitosan is a hydrophilic polysaccharide which derives from chitin by deacetylation. It has several applications, namely as a film that can be applied to preserve the quality and increase the shelf-life of food. Chitosan is insoluble in most solvents but it is soluble in dilute organic acids such as formic acid and acetic acid[1]. The properties of chitosan depend on the degree of deacetylation (DA) and molecular weight (MW). A broad antimicrobial activity has been attributed to chitosan, either for gram-negative, gram-positive bacteria and fungi. The aim of the present study is to evaluate the antimicrobial activity of a chitosan film prepared by casting. The chitosan was obtained from shrimp waste collected from shrimp processing factories of South Sonora (Mexico). Four bacteria (Bacillus cereus; Escherichia coli; Staphylococcus aureus and Listeria monocytogenes) and one fungus (Botrytis cinerea) were evaluated. Although L. monocytogenes and B. cinerea growth was not inhibited by the chitosan film, results showed a clear growth-inhibitory effect, at the two bacteria concentration levels tested, for B. Cereus, E. coli and S. aureus. Different antibacterial mechanisms have been proposed to explain chitosan antimicrobial activity[2-3]: i) chitosan may form an external barrier which inhibits essential nutrients adsorption; ii) chitosan can also penetrate the microbial cell, disturbing the metabolism of the cell by inhibiting the mRNA and protein synthesis; iii) chitosan may have an ionic surface interaction with the bacteria originating wall cell leakage. Although these mechanisms may take place simultaneously, the antimicrobial activity may also depend on the properties of chitosan (DA and MW).
- Analysis of Carotenoids, Vitamins and Folates in Traditional Foods from Black Sea AreaPublication . Sanches-Silva, A.; Albuquerque, T.G.; Ribeiro, T.; Valente, A.; Finglas, P.; Flores, A.C.; Santos, M.; D’Antuono, L.F.; Costa, H.S.; on behalf of the BaSeFood Black Sea area partnersNowadays, consumers are much more aware of nutritional composition and show especially interest in compounds with putative health benefits. Therefore, in the last few years, great attention has been devoted to the study of bioactive compounds in order to promote the consumption of traditional foods. The European project BaSeFood (Sustainable Exploitation of Bioactive Components Black Sea Area Traditional Foods) aims to study the traditional foods from the Black Sea Area, namely their nutritional and bioactive composition. In the frame of this project, the present work has analysed carotenoids, vitamins and folates in 33 traditional foods. Carotenoids and retinol and -tocopherol were extracted from samples with hexane/ethanol (4:3, v/v) and quantified by Ultra-high Pressure Liquid Chromatography (UPLC) with diode array detection (DAD). Some samples required saponification with methanolic KOH prior to chromatographic analysis. In general, the most abundant carotenoid was β-carotene. Most of the samples contain -tocopherol and do not present retinol. In order to quantify L-ascorbic acid, samples were stabilized with perchloric acid and metaphosphoric acid in ultrapure water. After dilution with mobile phase, samples were quantified by High Performance LC (HPLC)-DAD. One of the samples with highest L-ascorbic content was fruit of the evergreen cherry laurel (29.7 mg/100 g). Vitamin B2 was extracted after acid hydrolysis followed by dephosphorylation and HPLC with fluorescence detection (method EN 14152:2003, accredited according to ISO 17025). The determination of the total folate content in foodstuffs was carried out by a microbiological assay (EN 14131:2003, accredited according to ISO 17025). One of the highest vitamin B2 and total folate levels was found for roasted sunflower seeds (0.19 mg and 113 µg per 100 g of edible portion, respectively).
- Astaxanthin from shrimp by-products for active packagingPublication . Sanches-Silva, A.; Ribeiro, T.; Albuquerque, T.G.; Paseiro, P.; Sendón, R.; Bernaldo de Quirós, A.; López-Cervantes, J.; Sánchez-Machado, D.; Soto Valdez, H.; Angulo, I.; Pardo Aurrekoetxea, G.; Costa, H.S.
- Carotenoids, vitamins (A, B2, C and E) and total folate of traditional foods from Black Sea Area countriesPublication . Sanches-Silva, A.; Albuquerque, T.G.; Finglas, P.; Ribeiro, T.; Valente, A.; Vasilopoulou, E.; Trichopoulou, A.; Alexieva, I.; Boyko, N.; Costea, C.; Hayran, O.; Jorjadze, M.; Kaprelyants, L.; Karpenko, D.; D'Antuono, L.F.; Costa, H.S.BACKGROUND: Carotenoids, vitamins (A, B2, C and E) and total folate are related to health promotion. However, there are still many food matrices for which the content of these compounds is not available. In order to fill this gap, traditional foods from Black Sea Area countries (BSAC) were analysed in order to investigate their potential health benefits. RESULTS: The most abundant carotenoid was β-carotene. Plum jam was the sample with the highest β-carotene content (608 μg 100 g−1 edible portion). The group of vegetables and vegetable-based foods contributed most to β-carotene content. Evergreen cherry laurel presented the highest L-ascorbic acid content (29.9 mg 100 g−1 edible portion), while the highest riboflavin and total folate contents were found for roasted sunflower seeds. Approximately 61% of the analysed samples showed quantifiable amounts of α-tocopherol but did not contain retinol. CONCLUSION: Despite the great variability in the content of carotenoids, vitamins and total folate, most of the analysed traditional foods from BSAC can be considered good sources of these compounds. Therefore, owing to their putative health benefits, the consumption of those with higher contents of these compounds should be encouraged and promoted.
- Determination of Glucosamine by Ultra-high Pressure LC in Shrimp By-ProductsPublication . Sanches-Silva, A.; Ribeiro, T.; Albuquerque, T.G.; Paseiro, P.; Sendón, R.; López-Cervantes, J.; Sánchez-Machado, D.I.; Soto Valdez, H.; Angulo, I.; Aurrekoetxea, G.P.; Costa, H.S.Glucosamine is one of the most abundant monosacharides and is part of the structure of the chitosan and chitin, which compose the exoskeletons of crustaceans, other arthropods and the fungi cell walls. Shrimp by-products are a good source of glucosamine because about 45% of the animal is composed of inedible cephalothorax and exoskeleton. The project ‘Preparation of active packaging with antioxidant and antimicrobial activity based on astaxanthin and chitosan’ aims to develop a methodology for the incorporation of compounds obtained from shrimp waste in plastic matrices for the development of an active packaging with antimicrobial and antioxidant properties. In the frame of this project, shrimp by-products were fermented and insoluble chitin was purified by a sequence of steps: depigmentation, deproteinization, demineralization and blanching. The aim of the present work was to optimize a method to determine glucosamine by Ultra-high Pressure Liquid chromatography (Ultra Performance Liquid Chromatography, UPLC) with diode array detection (DAD) from shrimp by-products. First, an acid hydrolysis of the chitin of shrimp by-products is carried out. Afterwards, a derivatization is done because glucosamine does not contain a chromophore. The selected derivatization reagent was 9-fluorenylmethyl-chloroformate (Fmoc-Cl). The chromatographic separation is achieved using a vanguard pre-column (Acquity UPLCÒ HSS T3, 1.8 µm particle size) and a column (Acquity UPLCÒ HSS T3, 2.1 x 50 mm, 1.7 µm particle size) at 38 °C. Quantification of glucosamine was carried out at 265 nm. The mobile phase is a gradient of phase A [water (pH 6.5)/ methanol, 85:15 (v/v)] and phase B (acetonitrile) with a flow rate of 0.3 mL/min. The optimized UPLC method allows an excellent separation in just 10 min of the two anomers of glucosamine, of the Fmoc-Cl and of its corresponding alcohol, which is the hydrolysis product of the spontaneous reaction between Fmoc-Cl with water. Several samples have been analysed, some are commercial samples (chitosan with low molecular weight; chitosan with medium molecular weight; chitosan from shrimp shells; chitosan from crab shells), and three other samples produced from shrimp by-products in the frame of the project. Commercial samples presented a higher amount of glucosamine content than in-house produced samples.
- Migration of chitosan films prepared by solvent evaporation and extrusionPublication . Sanches-Silva, A.; Ribeiro, T.; Albuquerque, T.G.; Paseiro, P.; Sendón, R.; Bernaldo de Quirós, A.; López-Cervantes, J.; Sánchez-Machado, D.; Soto Valdez, H.; Angulo, I.; Pardo Aurrekoetxea, G.; Costa, H.S.Introduction: Chitosan has multiple applications and as inhibitor of microbial growth, there is interest in developing new methodologies to its incorporation into plastics, which would avoid microbial growth in foods. In the frame of the project “Preparation of active packaging with antioxidant and antimicrobial activity based on astaxanthin and chitosan” (PAPAAABAC), chitosan was extracted from shrimp by-products and used to prepare plastic films by solvent evaporation (casting) and extrusion. Material and Methods: Chitosan films were prepared by extrusion of polyamide and by casting. By casting, films were prepared at different concentrations (1%, 2%, and 3%) by dissolving chitosan in acetic acid aqueous solution 1% (w/v), with and without plasticizer (1% glycerol). By extrusion, chitosan pellets were made of polyamide 6 at 2%, 5%, 6%, 8%, and 10% with two different particle sizes (180 and 300 µm). Then, they were rolled in an extruder using a specific screw for polyamide. In order to determine chitosan in food simulants (ultrapure water and ethanol 95% (v/v)), it was degraded into the glucosamine units by hydrolysis and quantified by ultra high pressure liquid chromatography coupled with diode array detection after its derivatization with 9-fluorenylmethyl chloroformate. Results and conclusion: From the plastic films prepared by casting and by extrusion, only those prepared by casting without plasticizer presented chitosan migration that increases with the amount of chitosan added. These films could not be used to pack aqueous foodstuffs. However, the addition of a plasticizer (glycerol) has avoided the migration of chitosan. Therefore, the use of casting films with chitosan shall include a plasticizer in the formulation. Films prepared by extrusion presented no migration into both simulants indicating suitability to pack both aqueous and fatty foodstuffs.
- Ultra-high pressure LC for astaxanthin determination in shrimp by-products and active food packagingPublication . Sanches-Silva, A.; Ribeiro, T.; Albuquerque, T.G.; Paseiro, P.; Sendón, R.; Bernaldo de Quirós, A.; López-Cervantes, J.; Sánchez-Machado, D.; Soto Valdez, H.; Angulo, I.; Pardo Aurrekoetxea, G.; Costa, H.S.Nowadays, there is increasing interest in natural antioxidants from food by-products. Astaxanthin is a potent antioxidant and one of the major carotenoids in crustaceans and salmonids. An ultra-high pressure liquid chromatographic method was developed and validated for the determination of astaxanthin in shrimp by-products, and its migration from new packaging materials to food simulants was also studied. The method uses an UPLCW BEH guard-column (2.1 x 5 mm, 1.7mm particle size) and an UPLCW BEH analytical column (2.1 x 50 mm, 1.7mm particle size). Chromatographic separation was achieved using a programmed gradient mobile phase consisting of (A) acetonitrile–methanol (containing 0.05 M ammonium acetate)–dichloromethane (75:20:5, v/v/v) and (B) ultrapure water. This method was evaluated with respect to validation parameters such as linearity, precision, limit of detection, limit of quantification and recovery. Low-density polyethylene films were prepared with different amounts of the lipid fraction of fermented shrimp waste by extrusion, and migration was evaluated into food simulants (isooctane and ethanol 95%, v/v). Migration was not detected under the tested conditions.
- Ultra-high Pressure LC Method to Determine Astaxanthin in Shrimp By-Products and Migration Evaluation from an Active Plastic Film Produced with Shrimp Waste to Fatty Food SimulantsPublication . Sanches-Silva, A.; Ribeiro, T.; Paseiro, P.; Sendón, R.; Rodriguéz- Bernaldo de Quirós, A.; López-Cervantes, J.; Sánchez-Machado, D.I.; Soto-Valdez, H.; Angulo, I.; Aurrekoetxea, G.; Costa, H.S.Carotenoids have antioxidant properties allowing protection of tissues from oxidative damages and they are also beneficial in cardiovascular, immune, inflammatory and neurodegenerative diseases. Astaxanthin (3,3’-dihydroxy-β-β´-carotene-4-4´-dione) is a carotenoid classified as xanthophyl and it is one of the major carotenoids in crustaceans. The project ‘Preparation of active packaging with antioxidant and antimicrobial activity based on astaxanthin and chitosan’ aims to develop a methodology for the incorporation of compounds obtained from shrimp waste in plastic matrices for the development of an active packaging with antimicrobial and antioxidant properties. In the frame of this project, shrimp by-products were fermented and the silage was centrifuged. Three fractions were obtained and the upper phase, corresponding to the lipid fraction, was further analysed to determine astaxanthin content. The aim of the present work was to optimize a method to determine astaxanthin as well as seven other carotenoids and two vitamins (A and E) by ultra-high pressure liquid chromatography (Ultra Performance Liquid Chromatography, UPLC) with diode array detection (DAD) method in shrimp by-products. The chromatographic separation is achieved using a vanguard pre-column (UPLCÒ BEH, 1.7 µm particle size) and a column (UPLCÒ BEH, 2.1 x 50 mm, 1.7 µm particle size) at 20 °C. The mobile phase is a gradient of A (dichoromethane/methanol with ammonium acetate/acetonitrile 5:20:75 (v/v)) and B (ultrapure water) with a flow rate of 0.5 mL/min. The optimized UPLC method allows excellent peaks separation. Shrimp by-products (lipid fraction of shrimp waste, head and shell of cooked and raw shrimp) have been analysed. Moreover, low density polyethylene plastic films produced by extrusion with different amount of the lipid fraction of shrimp waste were prepared and tested regarding migration into fatty food simulants. Migration tests were carried out with isooctane and ethanol 95% (v/v), both alternative fatty food simulants. No migration was detected at the conditions tested, which are conventionally considered the most severe when the food contact material is intended for use at room temperature.