Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 13 de 13
Filter
Add more filters










Publication year range
1.
Polymers (Basel) ; 14(17)2022 Aug 29.
Article in English | MEDLINE | ID: mdl-36080624

ABSTRACT

The aim of this study was to develop an oxygen scavenger and antioxidant active packaging material for fried peanuts. The packaging solution, which has been made at the laboratory previously, has been developed by cast film extrusion and is composed of low-density polyethylene-ethylene vinyl alcohol-polyethylene terephthalate (LDPE/EVOH/PET)-based films containing ß-carotene (CAR). In comparison with film without additive, developed film presented an orange colouring (higher L* and b* values and lower a* values) and an increase in oxygen induction time (OIt) from 4.5 to 14.1 min. The incorporation of ß-carotene to the formulation also brings about a significant effect on the thermal stability as maximum degradation temperatures increased around 1%. Regarding the oxygen absorption capacity of the films, values of 1.39 ± 0.10 mL O2 per g of film at laboratory scale and 1.7 ± 0.3 mL O2 per g of multilayer (ML)/LDPE_CAR were obtained, respectively, after 3 days, proving the suitability of the packaging solutions as oxygen absorbers. To validate the packaging solution, the oxidative stability of fried peanuts packed in fabricated multilayer ß-carotene bags was evaluated for 3 months at 40 °C. The hexanal content remained constant during this period. Meanwhile, peanuts packed in ML without ß-carotene increased their hexanal content to 294%. This fact indicated a lower extent of oxidation in fried peanuts compared to food samples packaged in control films, suggesting the potential of ML/LDPE_CAR films as sustainable and antioxidant food packaging systems to offer protection against lipid oxidation in foods. Sensory evaluation confirmed that ML/LDPE_CAR films provided the peanut samples with an extra aroma due to the volatile degradation products of ß-carotene (such as ß-cyclocitral or 6-methyl-5-hepten-2-ol).

2.
Foods ; 10(7)2021 Jul 12.
Article in English | MEDLINE | ID: mdl-34359483

ABSTRACT

The presence of nuts in diets has notably increased due to their composition, and the presence of antioxidants and their unsaturated fatty acid profile has led to a considerable increase in their consumption. The volatile profile of nuts is important from different points of view. It affects consumer's selection, influences raw material selection for the production of composite foods, dictates variety selection in breeding programs, and, from a quality perspective, its changes can indicate food degradation or alteration. A review of the published bibliography concerning the determination of volatiles in nuts has been carried out. The information retrieved has been divided into four main sections. First, a discussion on the main volatiles present in nuts is performed; next, a revision of the methods used to determine the volatiles is presented; and, finally, two sections describing how harvesting conditions, healthy state and the thermal treatment of nuts modifies their volatile profile are added. Analysis of the published bibliography denoted the complexity of volatile determination and the different variables that can modify the compounds present in the volatile fraction of nuts.

3.
Polymers (Basel) ; 13(8)2021 Apr 16.
Article in English | MEDLINE | ID: mdl-33923568

ABSTRACT

The aim of this study was to develop a double function active packaging material for nuts. The packaging solution, on the one hand, integrated polybutadiene (PB) as an oxygen scavenger and, on the other hand, it incorporated peanut aroma (PA) to improve customer's sensorial experience. Different formulations based on low density polyethylene (LDPE), commercial PA (5 wt %) and PB at two levels (5 wt % and 13 wt %) were obtained by cast film extrusion. The obtained films were compared in terms of their mechanical, structural, optical and thermal properties confirming a plasticizing effect of PA and PB resulting in an increase in the ductility of the polymer and in a slight decrease in the thermal properties, maintaining their transparency. Regarding the oxygen capacity of the films, values of 4.4 mL and 2.7 mL O2 g-1 film were obtained for PE/PA/PB13 and PE/PA/PB5, respectively, after 6 days proving the suitability of the UV irradiation treatment in improving the oxygen absorption capacity of PB without the need of a metal catalyst. The aroma retention capacity into the polymer matrix was also evaluated in the developed formulations. The incorporation of PB in 13 wt % into a LDPE matrix improved the PA retention. This behavior was attributed to the ability of PB in enhancing cross-linking of LDPE as the concentration of PB increases. The results suggested the potential of PE/PB/PB13 films as oxygen scavenger and aromatic food packaging system to offer protection against lipid oxidation in nuts.

4.
Foods ; 10(1)2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33450909

ABSTRACT

Almonds show a great variability in their chemical composition. This variability is a result of the existence of a diverse range of almond cultivars, the self-incompatibility of most almond cultivars, and the heterogeneous harvesting conditions found around the different locations where almons are grown. In the last years, the discrimination among almond cultivars has been the focal point of some research studies to avoid fraud in protected geographical indications in almond products and also for selecting the best cultivars for a specific food application or the most interesting ones from a nutritional point of view. In this work, a revision of the recent research works related to the chemical characterization and classification of almond cultivars from different geographical origins has been carried out. The content of macronutrients, tocopherols, phytosterols, polyphenols, minerals, amino acids, and volatile compounds together with DNA fingerprint have been reported as possible cultivar and origin markers. The analysis of the results showed that no individual almond compound could be considered a universal biomarker to find differences among different almond cultivars. Hence, an adequate selection of variables or the employment of metabolomics and the application of multivariate statistical techniques is necessary when classification studies are carried out to obtain valuable results. Meanwhile, DNA fingerprinting is the perfect tool for compared cultivars based on their genetic origin.

5.
Antioxidants (Basel) ; 9(7)2020 Jul 06.
Article in English | MEDLINE | ID: mdl-32640717

ABSTRACT

Agricultural selection programmes are, today, working hard to obtain novel raspberry cultivars with higher nutritional and commercial quality. One of those cultivars is "Adelita". This study aims to provide novel tools for raspberry cultivar identification-more specifically, the differentiation of "Adelita" from other raspberry cultivars. To perform this study, five "Adelita" samples were analysed-four cultivated in Spain and one, in Morocco-and they were compared to seven samples from six raspberry cultivars ("P04", "Lupita", "Enrosadira", "P10", "Quanza" and "Versalles"). The physical parameters (mass, length, equatorial diameter and firmness) combined with the Total Phenolic Content (TPC); the antioxidant capacity according to the antioxidant activity tested with the 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) methods; and the main target volatile compounds were used as independent variables. Principal component and cluster analysis showed that the target volatiles and physical parameters together with the TPC and DPPH values could be useful to classify Adelita cultivars separately from the rest of the cultivars included in the work. Those results proved that the developed methodology could be proposed as a reliable approach for the identification of cultivar fraud in the supply chain.

6.
J Sci Food Agric ; 100(12): 4549-4557, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32419165

ABSTRACT

BACKGROUND: The study of almond fat stability is essential from a quality control perspective meanly because, in most of the cases, almonds are sold skinned and thermally treated. In this work an alternative method to Rancimat test based on attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) spectrometry was adapted for checking the induced degradation at 75 °C of seven almond oil cultivars, three of the top Californian producing varieties, and, four traditional cultivars harvested in Spain. RESULTS: The thermal oil degradation evolution was followed by measuring the changes in the absorbance of the selected FTIR spectra bands (3470, 3006, 1730, 1630, 988 and 970 cm-1 ). A first-order kinetic behaviour was observed, after an induction time in all bands. CONCLUSIONS: Kinetic coefficients and induction times were easily obtained as the absorbance values (from difference spectra) fitted to pseudo-first-order kinetics after the induction time. Principal component analysis was applied to the kinetic parameters to visualize which variables could be useful to classify the almond cultivars based on their resistance to thermal oxidation processes. It was found that selecting only the induction times corresponding to the bands 3470, 3006, 1630 and 970 cm-1 a separate classification of the Californian cultivars from the Spanish ones was possible. Finally, a linear discriminant analysis was assayed using only the four induction times previously selected. Validated classification and correct in 100% of the cases was obtained for all the samples based on their Spanish or Californian origin. © 2020 Society of Chemical Industry.


Subject(s)
Plant Oils/chemistry , Prunus dulcis/chemistry , Spectroscopy, Fourier Transform Infrared/methods , Cooking , Discriminant Analysis , Hot Temperature , Kinetics , Oxidation-Reduction , Principal Component Analysis , Prunus dulcis/classification , Spain
7.
Antioxidants (Basel) ; 8(11)2019 Nov 14.
Article in English | MEDLINE | ID: mdl-31739458

ABSTRACT

In this study, six different sofrito formulations were compared with the raw recipe for total phenolic content (TPC), antioxidant activity tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric-reducing antioxidant power (FRAP) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) methods. The volatile profile was also obtained by the headspace solid-phase microextraction-gas chromatography mass spectrometry (HS-SPME-GC-MS) procedure. The cooking process and the addition of herbs, and garlic improved the final content of antioxidant compounds compared to the basic recipe and the raw ingredients. The total volatile content was higher in the samples that contained rosemary and thymus. Some of the volatiles had proven antioxidant properties and for that reason the sofrito with rosemary with the higher volatile content was also the one with the higher antioxidant capacity and TPC. In conclusion, as well as the processing technique, the addition of selected typical Mediterranean herbs apart from given flavour can contribute to improving the nutritional antioxidant profile of dishes and be used as a natural method to increase the shelf-life of preparation.

8.
Food Chem ; 300: 125203, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31330367

ABSTRACT

Microwave (MW) radiation was applied to perform the separation of triacylglycerols (TGs) in oil samples. The novelty of the work lies in the application of MW radiation to assist the separation of several non-polar compounds employing a totally organic mobile phase. Once the influence of the evaporative light scattering detector (ELSD) variables on the sensitivity was optimized, the TGs separation was compared conditioning the column with either a conventional HPLC or a MW oven. Contrary to previous applications in which the mobile phase contained water, the improvement in sensitivity using MW was not as significant in comparison with conventional heating but it allowed a shortening in the retention times of several TGs in about 50% respect elution at room temperature. The method was finally applied for the quantification of most common TGs in almond, tiger nut, and argan oil.


Subject(s)
Chromatography, High Pressure Liquid/methods , Food Analysis/methods , Plant Oils/chemistry , Triglycerides/analysis , Triglycerides/isolation & purification , Chromatography, High Pressure Liquid/instrumentation , Food Analysis/instrumentation , Microwaves , Plant Oils/analysis , Scattering, Radiation , Temperature , Water
9.
Sci Total Environ ; 639: 228-236, 2018 Oct 15.
Article in English | MEDLINE | ID: mdl-29787906

ABSTRACT

In this study, the removal of parabens from waters, using a combined treatment of magnetic ion exchange resins and subsequent filtration through nanofiltration membranes, was investigated. The selected parabens were methylparaben, ethylparaben, propylparaben and butylparaben. Two different magnetic anionic exchanger resins, MIEX® DOC and MIEX® GOLD, and two nanofiltration membranes (NF), NF-90 and DESAL-HL, were tested. The study was carried out using mono and multicomponent systems, using deionized water and natural waters sampled from two different rivers. In this way, competitive and matrix effects could be evaluated. The results showed, that with the combined treatments, higher elimination rates were obtained. The best removal efficiencies were obtained when the DOC resin was combined with both NF-90 and DESAL-HL membranes. Thus, butylparaben and propylparaben reached removal yields around 100% with both membranes, whereas the corresponding values for methylparaben were 91%, when the NF-90 membrane was employed, or 92% when DESAL-HL membrane was utilized. The elimination rates of ethylparaben with the same treatments were 96% with the NF-90 and 97% when the DESAL-HL membrane was combined with the DOC resin. The elimination percentages were higher as the paraben alkyl chain length increased. In addition, no competitiveness or matrix effects were detected. When the MIEX® GOLD resin was used for pre-treatment, membrane fouling worsened which indicated that resin selection needs to be carefully considered to achieve the best results.


Subject(s)
Ion Exchange Resins/chemistry , Parabens/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Filtration/methods , Parabens/analysis , Water Pollutants, Chemical/analysis
10.
Rev. esp. investig. oftalmol ; 4(2): 101-104, abr.-jun. 2014. ilus
Article in Spanish | IBECS | ID: ibc-129956

ABSTRACT

Introducción. La sífilis es una enfermedad sistémica crónica de transmisión sexual causada por el Treponema pallidum. Puede afectar a cualquier estructura y se la conoce, entre otras, como "la gran simuladora". Caso clínico. Varón de 29 años acude por disminución de agudeza visual (AV) de ojo izquierdo (OI) de 10 días de evolución. El fondo de ojo (FO) derecho, presenta papila con bordes borrosos congestivos y en OI, lesión coriorretiniana blanco-amarillenta en hemirretina superior con focos subrretinianos. Sospechamos necrosis retiniana aguda en OI e iniciamos tratamiento con aciclovir vía intravenosa (IV). A la espera de resultados, apreciamos una progresión de la necrosis y disminución de AV. Con diagnóstico serológico positivo para sífilis y VIH, se inició tratamiento con penicilina G sódica durante 14 días, observándose en controles posteriores la mejoría del cuadro (AU)


Introduction. Syphilis is a chronic systemic disease sexually transmitted disease caused by Treponema pallidum. It can affect any structure and is known, among others, as "the great imitator". Clinical case. A 29 year old presents with decreased visual acuity (VA) of left eye (LE) of 10 days duration. The fundus (FO) right, presents papilla with congestive blurry edges and OI, yellowish-white chorioretinal lesion in upper hemiretina subrretinianos foci. Acute retinal necrosis suspect OI and started treatment with acyclovir intravenously (IV). Pending results, we appreciate a progression of necrosis and decreased AV. With positive serodiagnosis for syphilis and HIV, she was treated with penicillin G sodium for 14 days, showing improvement in subsequent checks the box (AU)


Subject(s)
Humans , Male , Adult , Retinal Necrosis Syndrome, Acute/diagnosis , Syphilis/complications , HIV Infections/diagnosis , Penicillin G/therapeutic use , Neurosyphilis/complications
11.
Rev. esp. investig. oftalmol ; 3(4): 211-213, oct.-dic. 2013. ilus
Article in Spanish | IBECS | ID: ibc-132291

ABSTRACT

Caso clínico. Paciente miope magno que presenta un desprendimiento coroideo (DC) hemorrágico aposicional con hemorragia vítrea en ojo izquierdo (OI), confirmado por ecografía, tras ser intervenido de implante secundario de lente intraocular (LIO). Como antecedentes de interés presenta intervención de catarata traumática en OI 20 años antes. Presenta una agudeza visual de percepción de luz objetivada mediante potenciales evocados visuales con estímulo flash. Se decide intervenir quirúrgicamente realizando un drenaje a través de tres esclerotomías a 3mm del limbo, localizando las zonas de DC mediante transiluminación, y vitrectomía vía limbar de 23G con introducción de aceite de silicona de 5000 centistokes, consiguiendo buenos resultados anatómicos. Conclusiones. Decidimos abordaje quirúrgico debido a la aposición completa del DC y la presencia de hemorragia vítrea. La vitrectomía vía limbar nos proporciona una entrada segura a la cavidad vítrea, evitando el espacio supracoroideo. Pero presenta la limitación de que la longitud de los instrumentos no está diseñada para tal fin (AU)


Case report. A high myopic patient who underwent a secondary intraocular lens implant presents an appositional hemorrhagic choroidal detachment with vitreous hemorrhage in the left eye, confirmed by ultrasounds. As past medical history he had a traumatic cataract surgery 20 years ago in his left eye. He presents a visual acuity of light perception objectified by visual evoked potentials by flash stimulus. We decide a surgical intervention with drainage across three sclerotomies 3 mm from limbus, locating the choroidal detachment areas by transillumination, and 23G limbal vitrectomy with 5000 centistokes silicone oil introduction, achieving good anatomy results. Conclusions. We decided a surgical intervention due to the complete apposition of the choroidal detachment and the presence of vitreous hemorrhage. The limbal victrectomy provides a save entrance to the vitreous cavity, avoiding the suprachoroidal space but is limited by the length of the surgical instruments which are not designed for that purpose (AU)


Subject(s)
Humans , Male , Ophthalmology/education , Scleral Buckling , Scleral Buckling/methods , Vitrectomy , Vitrectomy/instrumentation , Pharmaceutical Preparations , Ophthalmology/organization & administration , Scleral Buckling/instrumentation , Scleral Buckling , Vitrectomy/adverse effects , Vitrectomy , Pharmaceutical Preparations , Pharmaceutical Preparations/supply & distribution
12.
Arch Soc Esp Oftalmol ; 77(8): 455-8, 2002 Aug.
Article in Spanish | MEDLINE | ID: mdl-12185622

ABSTRACT

PURPOSE/METHOD: The choroidal neovascularization (CNV) may be associated with several types of choroidal tumors. The polypoidal choroidal vasculopathy (PVC) is a variant of the choroidal neovascularization. We present a case of PCV associated with melanocytoma of the optic nerve. RESULTS/CONCLUSIONS: Although we cannot rule out that these two entities are independent of each other, the reported cases of choroidal tumors with CNV, the publication of a similar case and the epidemiological similarity between melanocytoma and PCV leads us to think that they may be related. We confirm the efficacy of laser argon treatment (Arch Soc Esp Oftalmol 2002; 77: 455-458).


Subject(s)
Choroidal Neovascularization/etiology , Nevus/complications , Optic Nerve Neoplasms/complications , Choroidal Neovascularization/diagnosis , Female , Humans , Middle Aged , Nevus/diagnosis , Optic Nerve Neoplasms/diagnosis
13.
Arch. Soc. Esp. Oftalmol ; 77(8): 455-458, ago. 2002.
Article in Es | IBECS | ID: ibc-19118

ABSTRACT

Objetivo/Método: La neovascularización coroidea (NVC) puede asociarse a varios tipos de tumores coroideos. La vasculopatía coroidal polipoidea (VCP) es una variante de la neovascularización coroidea. Presentamos un caso de VCP asociado a melanocitoma del disco óptico. Resultados/Conclusiones: Aunque no podemos descartar que sean dos entidades independientes, la existencia de casos descritos en la literatura de tumores coroideos asociados a neovascularización coroidea, la aparición de otro caso similar al nuestro en la literatura, y las coincidencias epidemiológicas entre ambos cuadros nos induce a pensar que la VCP y el melanocitoma podrían estar relacionados. Se confirma la eficacia del tratamiento con la fotocoagulación con láser de Argón (AU)


Subject(s)
Middle Aged , Female , Humans , Nevus , Choroidal Neovascularization , Optic Nerve Neoplasms
SELECTION OF CITATIONS
SEARCH DETAIL
...