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1.
Foods ; 12(5)2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-36900503

RESUMEN

Honey is a worldwide known and appreciated food product. Its appreciation by consumers is due to both its nutritional properties and the extremely reduced processing. The floral origin, color, aroma and taste are key factors in determining the quality of honey. Nevertheless, rheological properties, as crystallization rate, play a fundamental role in the perceived overall quality. Indeed, crystallized honey is often considered of poor quality by consumers, but a fine-grained or creamy texture is becoming interesting from the producers' side. The purpose of this study was to investigate textural and aromatic properties and consumers' perception and acceptance of two monofloral honeys that were differently crystallized. Liquid and creamy samples were obtained from crystallized samples. Physico-chemical, descriptive and dynamic sensory analysis, as well as consumer and CATA tests, were conducted on the three honey textures. The physico-chemical analysis well-discriminated the crystallization levels and evidenced that, although the honey variety was different, the textural properties of the creamy samples are very similar. Crystallization was shown to affect the honey sensory perceptions: liquid samples were sweeter, but less aromatic. Consumer tests allowed the validation of panel data and confirmed consumers' higher appreciation for liquid and creamy honey.

2.
Front Neurol ; 12: 633574, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33716936

RESUMEN

Background/Objective: During the COVID-19 pandemic, smell and taste disorders emerged as key non-respiratory symptoms. Due to widespread presence of the disease and to difficult objective testing of positive persons, the use of short surveys became mandatory. Most of the existing resources are focused on smell, very few on taste or trigeminal chemosensation called chemesthesis. However, it is possible that the three submodalities are affected differently by COVID-19. Methods: We prepared a short survey (TaSCA) that can be administered at the telephone or through online resources to explore chemosensation. It is composed of 11 items on olfaction, taste, and chemesthesis, in order to discriminate the three modalities. We avoided abstract terms, and the use of semiquantitative scales because older patients may be less engaged. Statistical handling included descriptive statistics, Pearson's chi-squared test and cluster analysis. Results: The survey was completed by 83 persons (60 females and 23 males), which reported diagnosis of COVID-19 by clinical (n = 7) or molecular (n = 18) means, the others being non-COVID subjects. Cluster analysis depicted the existence of two groups, one containing mostly asymptomatic and one mostly symptomatic subjects. All swab-positive persons fell within this second group. Only one item, related to trigeminal temperature perception, did not discriminate between the two groups. Conclusions: These preliminary results indicate that TaSCA may be used to easily track chemosensory symptoms related to COVID-19 in an agile way, giving a picture of three different chemosensory modalities.

3.
Food Chem ; 141(3): 2802-11, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23871027

RESUMEN

The quality of 10 buckwheat honeys, collected from Italian and est European beekeepers declaring to produce monofloral honey, were evaluated by means of their pollen, physicochemical, phenolic and volatile composition data. The results of the traditional analyses and in particular electrical conductivity, optical rotation, pH and sugar composition revealed some poorly pure samples that could not fit in the buckwheat tipology. Honey volatiles, analysed by solid phase microextraction (SPME) and gas chromatography-mass-spectrometry (GC/MS), showed more than 100 volatile compounds, most of them present in all honey samples but with quantitative variation. Besides many furfural derivates, 3-methylbutanoic acid was the main volatile compound found in most of honeys. Also the presence of 2- and 3-methylbutanal and pheynalcetaldehyde confirmed the typical buckwheat aroma of some studied samples, corroborating physicochemical data. The HPLC phenolic profile was similar across the samples and p-hydroxybenzoic and p-coumaric acids proved to be the main components.


Asunto(s)
Fagopyrum/química , Miel/análisis , Fenoles/análisis , Compuestos Orgánicos Volátiles/química , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Polen/química , Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles/aislamiento & purificación
4.
Phytochem Anal ; 23(3): 260-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21853496

RESUMEN

INTRODUCTION: Propolis is a resinous substance collected by bees from exudates of different plants that is rich in well-known health-relevant phenolic compounds such as flavonoids and phenolic acids. Propolis extracts are very complex matrices difficult to study. Different analytical methods are usable to analyse propolis extracts and to obtain chemical fingerprint but to our knowledge NMR has not previously been used for this purpose. OBJECTIVE: This study aims to demonstrate that it is possible to use ¹H-NMR for the simultaneous recognition of phenolic compounds in complex matrices, such as propolis extracts, using appropriate tools for spectra pre-treatment and analysis. METHODOLOGY: In this work 12 typical phenolic propolis compounds (apigenin, chrysin, galangin, kaempferol, quercetin, naringenin, pinocembrin, pinostrobin, caffeic acid, cinnamic acid, p-coumaric acid and ferulic acid) were considered as reference compounds and their presence in samples was verified by HPLC-MS. A simple ¹H-NMR sequence was used to obtain spectra of samples. Spectra were pre-treated by using an appropriate tool for spectra alignment and analysed by using software for the study of spectra originated from complex matrices. Sixty-five propolis samples were used to test the proposed identification procedure. RESULTS: Ten out of 12 considered compounds were identified as statistically significant in most of the samples. CONCLUSION: This work suggests that it is possible to efficiently use ¹H-NMR, coupled with appropriate spectral analytical tools, for the simultaneous detection of phenolic compounds in complex matrices.


Asunto(s)
Flavonoides/análisis , Hidroxibenzoatos/análisis , Espectroscopía de Resonancia Magnética/métodos , Extractos Vegetales/análisis , Própolis/análisis , Animales , Antiinfecciosos/análisis , Antiinfecciosos/aislamiento & purificación , Apigenina/análisis , Apigenina/aislamiento & purificación , Abejas , Ácidos Cafeicos/análisis , Ácidos Cafeicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Cinamatos/análisis , Cinamatos/aislamiento & purificación , Ácidos Cumáricos/análisis , Ácidos Cumáricos/aislamiento & purificación , Flavanonas/análisis , Flavanonas/aislamiento & purificación , Flavonoides/aislamiento & purificación , Hidroxibenzoatos/aislamiento & purificación , Quempferoles/análisis , Quempferoles/aislamiento & purificación , Espectrometría de Masas , Extractos Vegetales/aislamiento & purificación , Propionatos , Própolis/aislamiento & purificación , Quercetina/análisis , Quercetina/aislamiento & purificación , Reproducibilidad de los Resultados
5.
J Sep Sci ; 30(7): 1061-9, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17566341

RESUMEN

A new CZE method was developed and compared with HPLC for the determination of (E)-10-hydroxy-2-decenoic acid (10-HDA) in royal jelly (RJ) samples of different geographical origin. The results obtained with the CZE method were highly correlated with those of HPLC (p < 0.01). Under optimized conditions, CZE employed minimal amounts of 50 mM tetraborate buffer as BGE, without the addition of organic solvents, EOF or pH modifiers. The CZE method showed a wide linear response range (0.006-0.808 mg 10-HDA/mL), a good sensitivity (LOD and LOQ were 0.002 and 0.004 mg/mL, respectively) and a satisfactory instrumental repeatability with respect to migration time and peak area (RSD% less than 1.0 and 2.0% on migration time for intra- and interday assay, respectively and less than 2.0 and for 4.0% on peak area for intra- and interday assay, respectively). The 10-HDA content in RJ ranged from 0.8 to 3.2 g/100 g of RJ and a significant difference (p < 0.05) was found between the Italian and extra-European average values: 2.5 and 1.6 g/100 g of RJ, respectively, according to the CZE data. The possibility of application of CZE for routine analyses on RJ and RJ based products to verify their authenticity is highlighted here.


Asunto(s)
Electroforesis Capilar/métodos , Ácidos Grasos Monoinsaturados/análisis , Ácidos Grasos/química , Cromatografía Líquida de Alta Presión/métodos , Sensibilidad y Especificidad , Solventes/química , Estereoisomerismo , Agua/química
6.
Phytochem Anal ; 15(4): 235-40, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15311843

RESUMEN

The validation of rapid, low-cost spectrophotometric procedures for the quantification of the three main groups of bioactive substances (flavones and flavonols, flavanones and dihydroflavonols, and total phenolics) in poplar-type propolis has been performed. A spectrophotometric assay based on the formation of an aluminium chloride complex was applied for the quantification of total flavones and flavonols using galangin as standard. Because of the high amount of flavanones and dihydroflavonols in "poplar type" propolis, the introduction of a distinct procedure for their quantification was considered of special significance and the DAB9 colorimetric method was applied for the purpose. Total phenolic content was measured by the Folin-Ciocalteu procedure using a mixture of pinocembrin and galangin as a reference. The procedures were validated using a model mixture of compounds representing the poplar-type propolis composition as found in previous studies. The accuracy (recovery) varied in the range 84-109%, and the relative standard deviation was 0.5-6.2%. The developed spectrophotometric procedures were applied to six poplar type propolis samples. The results were verified independently by a HPLC procedure. The two sets of results agreed satisfactory, as proven by Student's t-test.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Populus/metabolismo , Própolis/química , Antiinfecciosos/química , Flavanonas/análisis , Flavonoides/análisis , Fenoles/análisis , Reproducibilidad de los Resultados , Espectrofotometría/métodos
7.
Rev. Fac. Farm. (Merida) ; 39: 26-36, 2000. tab
Artículo en Español | LILACS | ID: lil-308934

RESUMEN

Los estándares internacionales de la miel de abejas especificados en una Directiva Europea de la Miel y en los Estándares para Miel del Codex Alimentarius, se encuentran en revisión. En este trabajo se discute el conocimiento actual de los diferentes criterios de calidad de la miel. Los borradores de trabajo son los documentos de referencia para la revisión de los estándares y de los métodos sugeridos para determinar los siguientes factores de calidad: humedad, cenizas, acidez, hidroximetilfurfural, azúcares reductores, sacarosa aparente, actividad diastásica y sólidos insolubles en agua. Durante los pasados 30 años se han publicado pocos trabajos sobre contenido de azúcares reductores y cenizas en mieles; siendo los azúcares específicos y la conductividad eléctrica más utilizados. Basados en esta información, se proponen estándares internacionales de la miel basados en la suma del contenido de glucosa y fructosa, de sacarosa y la conductividad eléctrica. Además, se discute el uso de otros factores de calidad de la miel, como actividad de la invertase; prolina y rotación específica; utilizados en numerosos países. Finalmente, se presentan sugerencias para actualizar las normas venezolanas para control de calidad de miel de abejas


Asunto(s)
Abejas , Unión Europea , Normas de Calidad de los Alimentos , Miel , Insectos , Gestión de la Calidad Total , Estándares de Referencia , Farmacología , Venezuela
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