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1.
Molecules ; 27(10)2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35630725

RESUMEN

The number of food frauds in coconut-based products is increasing due to higher consumer demands for these products. Rising health consciousness, public awareness and increased concerns about food safety and quality have made authorities and various other certifying agencies focus more on the authentication of coconut products. As the conventional techniques for determining the quality attributes of coconut are destructive and time-consuming, non-destructive testing methods which are accurate, rapid, and easy to perform with no detrimental sampling methods are currently gaining importance. Spectroscopic methods such as nuclear magnetic resonance (NMR), infrared (IR)spectroscopy, mid-infrared (MIR)spectroscopy, near-infrared (NIR) spectroscopy, ultraviolet-visible (UV-VIS) spectroscopy, fluorescence spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and Raman spectroscopy (RS) are gaining in importance for determining the oxidative stability of coconut oil, the adulteration of oils, and the detection of harmful additives, pathogens, and toxins in coconut products and are also employed in deducing the interactions in food constituents, and microbial contaminations. The objective of this review is to provide a comprehensive analysis on the various spectroscopic techniques along with different chemometric approaches for the successful authentication and quality determination of coconut products. The manuscript was prepared by analyzing and compiling the articles that were collected from various databases such as PubMed, Google Scholar, Scopus and ScienceDirect. The spectroscopic techniques in combination with chemometrics were shown to be successful in the authentication of coconut products. RS and NMR spectroscopy techniques proved their utility and accuracy in assessing the changes in coconut oil's chemical and viscosity profile. FTIR spectroscopy was successfully utilized to analyze the oxidation levels and determine the authenticity of coconut oils. An FT-NIR-based analysis of various coconut samples confirmed the acceptable levels of accuracy in prediction. These non-destructive methods of spectroscopy offer a broad spectrum of applications in food processing industries to detect adulterants. Moreover, the combined chemometrics and spectroscopy detection method is a versatile and accurate measurement for adulterant identification.


Asunto(s)
Cocos , Espectrometría Raman , Aceite de Coco , Aceites de Plantas/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos
2.
Meat Sci ; 172: 108318, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32980722

RESUMEN

In this study, ɛ-polylysine (ɛ-PL) or ɛ-polylysine nanoparticle (ɛ-PLN) combined with plants extracts (including green tea, olive leaves and stinging nettle extracts) were used as nitrite replacers in frankfurter-type sausages. The sausage samples were wrapped in polyethylene bags (in vacuum conditions) and their physicochemical, microbiological and sensory properties were evaluated during 45 days of refrigerated storage. The results showed that the incorporation of ɛ-polylysine had no significant effects on proximate composition of sausages. However, ɛ-PL and ɛ-PLN sausages had significantly (P < 0.05) lower lightness, redness and higher yellowness compared to control samples. At the end of storage, sausages formulated with ɛ-PLN had significantly (P < 0.05) higher contents of phenolic compounds and lowest TBARS values. Microbiological counts also indicated that ɛ-PLN displayed significantly higher inhibitory effects. Higher sensory indices were obtained in ɛ-PLN sausages. Based on the obtained results, ɛ-PLN was effective to improve frankfurter-type sausages shelf life. Therefore, these ingredients could be useful for frankfurter-type sausages production as nitrite replacers.


Asunto(s)
Productos de la Carne/análisis , Nanopartículas , Extractos Vegetales , Polilisina , Animales , Productos Biológicos , Bovinos , Color , Comportamiento del Consumidor , Femenino , Almacenamiento de Alimentos , Humanos , Masculino , Productos de la Carne/microbiología , Fenoles/análisis , , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Urtica dioica
3.
Acta Histochem ; 123(1): 151656, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33249311

RESUMEN

The present article sought to evaluate the impact of curcumin-loaded superparamagnetic iron oxide (Fe3O4) nanoparticles (NPs) on the histological variables and apoptotic agents in adult male rats after 3-weeks of methylphenidate (MPH) oral administration (20 mg/kg) versus vehicle therapy on the testis. Twenty-four male rats have been categorized randomly into four groups, in which Group 1 has been chosen as the controls, and Group 2 has been a vehicle and taken the sesame oil as curcumin carrier. Moreover, Group 3 has been taken MPH (20 mg/kg by gavage for 21 consecutive days). Group 4 received MPH plus Curcumin nanoparticles (5.4 mg/100 g) for twenty-one consecutive days. Then, testis histology, apoptosis as well as stereology have been examined. According to the examinations, curcumin nanoparticles are significantly capable of improving the sperms and stereological variables; for example, round spermatid and Leydig cells by enhancing the level of the serum testosterone in comparison with the MPH and vehicle groups. Besides, it was found that the gene expression in inflammation pathways and apoptosis genes largely diminished in the treatment group by curcumin nanoparticles in comparison with the MPH and vehicle groups, also we observed considerable differences for the weight of testes between the examined groups. Therefore, Curcumin effectively inhibited the testis damages and MPH-induced apoptosis, indicating possible protecting features of the Curcumin nanoparticles in opposition to MPH.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/biosíntesis , Curcumina/farmacología , Portadores de Fármacos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Nanopartículas de Magnetita/uso terapéutico , Metilfenidato/efectos adversos , Testículo/metabolismo , Animales , Masculino , Metilfenidato/farmacología , Distribución Aleatoria , Ratas , Ratas Wistar
4.
J Food Prot ; 83(5): 754-761, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32294761

RESUMEN

ABSTRACT: Two different potato chip coatings-aqueous extracts including Zataria multiflora and Allium hirtifolium at concentrations of 1, 3, 5, and 7% and hydrocolloids individually or in combination-were used to decrease acrylamide content, and their effects on the characteristics of the product were then investigated. According to the results, the incorporation of hydrocolloids as the coating was more efficient in the reduction of acrylamide production than with the extracts. Also, the application of each extract and hydrocolloids individually can be considered a more efficient technique for acrylamide reduction than their mixture. In this regard, the economic aspects of the application of hydrocolloids in the coating of fried potato crisps can be evaluated.


Asunto(s)
Acrilamida , Contaminación de Alimentos/prevención & control , Solanum tuberosum , Acrilamida/análisis , Coloides , Manipulación de Alimentos , Solanum tuberosum/química
5.
Fungal Biol ; 123(8): 611-617, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31345415

RESUMEN

The current investigation was aimed to estimate the prevalence and concentration of ochratoxin A (OTA) in different types of coffee and coffee-based products with the aid of a systematic review and meta-analysis. Therefore, the recommended databases including PubMed, Scopus, and Embase from Jan 1983 to Oct 2018 were screened to retrieve the related citations. In this regard, among 1041 explored articles in the identification step, thirty six articles with 3182 samples were included in the meta-analysis and meta-regression. According to findings, the global pooled concentration and prevalence of OTA was calculated as 3.21 µg/kg (95% CI: 3.08-3.34 µg/kg) and 53.0 % (95% CI: 43.0-62.0), respectively. Also, direct correlations between the increases in poverty as well as the amount of annual precipitation and prevalence of OTA was noted, while with decreasing in HDI the prevalence of OTA in coffee significantly was increased. Moreover, the lowest and highest concentrations of OTA in coffee were observed in Taiwan (0.35 µg/kg) and Turkey (79.0 µg/kg), respectively. The outcome of this meta-analysis can be used for the building of risk assessment models aiming to derive data for the development of specific actions to reduce the exposure to this mycotoxin in coffee and coffee-based products.


Asunto(s)
Coffea/química , Café/química , Contaminación de Alimentos/estadística & datos numéricos , Ocratoxinas/análisis , Contaminación de Alimentos/análisis , Semillas/química
6.
J Sci Food Agric ; 99(10): 4561-4570, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-30883768

RESUMEN

BACKGROUND: There is limited information in the literature concerning the feasibility of using algal extracts as natural additives for improvement of the quality and shelf-life of meat products. Hence, a Fucus vesiculosus extract (FVE) at the concentrations of 250 mg kg-1 (FVE-250), 500 mg kg-1 (FVE-500) and 1000 mg kg-1 (FVE-1000) were added to pork patties with linseed oil oleogel as a fat replacer. RESULTS: Total polyphenol content of FVE was determined to be 20 g phloroglucinol equivalents 100 g-1 extract. Antioxidant values ranged from 37.5 µmol of Trolox equivalents (TE) g-1 (FRAP assay) to 2111 µmol TE g-1 extract (ABTS assay). Regarding oxidation stability, FVE-1000 showed the lowest values of thiobarbituric acid-reactive substance and carbonyl content. On the other hand, FVE did not improve color, surface discoloration or odor attributes of patties during storage. Sensory evaluation revealed that there was no significant difference among all studied samples. CONCLUSION: Although FVEs have a high polyphenol content and antioxidant activities, they are not effective oxidation inhibitors for long-term storage of meat products. Therefore, additional measures or compounds should be considered when FVE is the only antioxidant in meat products. © 2019 Society of Chemical Industry.


Asunto(s)
Antioxidantes/análisis , Aditivos Alimentarios/análisis , Fucus/química , Productos de la Carne/análisis , Extractos Vegetales/análisis , Animales , Manipulación de Alimentos , Almacenamiento de Alimentos , Compuestos Orgánicos/análisis , Porcinos
7.
J Oleo Sci ; 65(9): 733-8, 2016 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-27477070

RESUMEN

In this study, the effect of three amplitudes of ultrasound-assisted solvent extraction (UASE) (0, 25 and 50 %; 100 W, 30 kHz; the 0% treatment serving as control) on yield and quality of extracted oil from P. khinjuk hull at various pretreatment times (15, 30 and 45 min) was evaluated. The highest oil yields at the three amplitude levels tested were 24.4, 29.8 and 37.8% for 0, 25 and 50 %, respectively. Although increase in pretreatment time increased oil yield, pretreatment time at 30 and 45 min did not significantly different for both 25 and 50% amplitude. Furthermore, UASE did not significantly affect fatty acid composition, peroxide value (PV), conjugated diene value (CDV) and anisidine value (AnV) of extracted oils. UASE also increased tocopherols and tocoterienols content of oils but pretreatment time at 30 and 45 min did not significantly different for them. Therefore, UASE increase yield and quality of extracted oil and reduce extraction time. All these advantages make UASE a good substitute for the extraction of oil.


Asunto(s)
Pistacia/química , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificación , Solventes/química , Ultrasonido , Factores de Tiempo
8.
Curr Microbiol ; 73(2): 265-72, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27155845

RESUMEN

This work were aimed to (a) determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Carum copticum essential oil (EO) against Escherichia. coli O157:H7 in vitro Trypticase Soy Broth, (TSB) and in ground beef; (b) evaluation of the effect of sub-inhibitory concentrations (sub-MICs) of EO on the growth of bacterium in TSB over 72 h (at 35 °C) and ground beef over 9 days (at 4 °C); and (c) investigation of gene expression involved in Shiga toxins production using relative quantitative real-time PCR method. The MIC in broth and ground beef medium were determined as 0.05 (v/v) and 1.75 % (v/w), respectively. In comparison with control cultures, the EO concentration of 0.03 % in broth caused reduction of colony counting as 1.93, 1.79, and 2.62 log10 CFU ml(-1) after 24, 48, and 72 h at 35 °C, and similarly EO (0.75 %) in ground beef resulted to reduction of colony counting as 1.03, 0.92, 1.48, and 2.12 log10 CFU g (-1) after 2, 5, 7, and 9 days at 4 °C, respectively. An increase and decrease in gene expression were observed as result of EO addition (0.03 %) to broth and (0.5 %) to ground beef was noticed, respectively.


Asunto(s)
Antibacterianos/farmacología , Carum/química , Escherichia coli O157/efectos de los fármacos , Aditivos Alimentarios/farmacología , Carne/microbiología , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Toxinas Shiga/genética , Animales , Bovinos , Recuento de Colonia Microbiana , Escherichia coli O157/genética , Escherichia coli O157/metabolismo , Toxinas Shiga/metabolismo
9.
J Sci Food Agric ; 94(11): 2205-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24343590

RESUMEN

BACKGROUND: Polyethylene terephthalate (PET) containers for food oil packaging were evaluated with a newly established determination method for terephthalic acid (TPA) and isophthalic acid (IPA). The analysis of monomers, TPA and IPA that migrate from PET bottles into oils was performed using high-pressure liquid chromatography with a diode array detector. Three types of commercial oils (sunflower oil, canola oil and blended oil which included sunflower oil, soy bean oil and cottonseed oil) were bottled in PET containers. These samples were incubated for 10 days at 49 °C as accelerated test condition. RESULTS: The means of recovery for this method varied from 70% to 72% and from 101% to 111% for TPA and IPA, respectively. The results showed that the amounts of specific migration of TPA and IPA into the samples conform to European Union legislation that identifies specific migration limits. More important, the results highlighted a different behavior of migration as a function of the fatty acid profile. CONCLUSION: Previous investigations have been performed with food simulants such as HB307 or 20% ethanol but our study used real food samples and determined trace amounts of the migrated compounds. Further investigation will be needed to better explain the influence of fatty acid conformation on migration of PET monomers.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Contaminación de Alimentos/análisis , Embalaje de Alimentos , Almacenamiento de Alimentos , Ácidos Ftálicos/análisis , Aceites de Plantas/química , Tereftalatos Polietilenos/análisis , Cromatografía Líquida de Alta Presión/métodos , Aceite de Semillas de Algodón , Dieta , Unión Europea , Ácidos Grasos/análisis , Ácidos Grasos Monoinsaturados , Humanos , Aceite de Brassica napus , Aceite de Soja , Aceite de Girasol
10.
J Food Sci ; 78(5): T792-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23534490

RESUMEN

It is important to have a reliable method to analyze pesticides in tea, a beverage commonly consumed in Iran. A validated method was developed for the determination of 20 pesticides in tea based on QuEChERS sample preparation and capillary gas chromatography-quadrupole mass spectrometry in selective ion monitoring mode (GC-MS/SIM) using triphenyl methane (TPM) solution as an internal standard. We used fortified, extracted, and cleaned-up tea samples instead of calibration standards for quantitation, which substantially reduced adverse matrix-related effects and negative recovery affected by graphite carbon black (GCB) on pesticide analysis. The recovery of pesticides at 3 concentration (40, 60, and 240 ng/g) ranged from 79.5% to 111.4% (n = 3). The method had acceptable repeatability with RSDr < 20%. The limits of quantification (LOQ) for all pesticides were ≤20 ng/g. The analytical results of the proposed method were in good agreement with proficiency test results (FAPAS, 19116). The recoveries and repeatabilities were in accordance with the criteria set by SANCO Guideline. The validated method was suitable for the analysis of pesticides in tea.


Asunto(s)
Residuos de Plaguicidas/análisis , Té/química , Calibración , Cromatografía de Gases y Espectrometría de Masas , Irán , Límite de Detección , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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