RESUMEN
The aim of this work was to obtain sweet quinoa seeds by a pearling process. Thus, two different pearling degrees (20% and 30%) were tested. Moreover, the effect of pearling process on saponins and phenolic content in quinoa were evaluated. To this end, GC-MS methodology was used to identify and quantify the saponins and reversed phase-high performance liquid chromatography coupled to DAD and mass spectrometer detectors was applied to study the phenolic composition. As expected, whole quinoa had the highest saponins and phenolics contents. An abrasion degree of 30% was necessary to obtain sweet quinoa (with a total saponin content lower than 110 mg/100 g). Obviously, this process caused a decrease of 21.5% and 35.2% of free and bound phenolic compounds, respectively. However, this decrease was lower if compared with other cereals. Thus, pearling process is a promising sustainable method to obtain sweet quinoa with a "green" approach.
Asunto(s)
Chenopodium quinoa/química , Fenoles/análisis , Saponinas/análisis , Semillas/químicaRESUMEN
Quinoa is a pseudocereal from South America that has received increased interest around the world because it is a good source of different nutrients and rich in antioxidant compounds. Thus, this study has focused on the effects of different agronomic variables, such as irrigation and salinity, on the phenolic and saponin profiles of quinoa. It was observed that irrigation with 25% of full water restitution, with and without the addition of salt, was associated with increases in free phenolic compounds of 23.16 and 26.27%, respectively. In contrast, bound phenolic compounds were not affected by environmental stresses. Saponins decreased if samples were exposed to drought and saline regimens. In situations of severe water deficit, the saponins content decreased 45%, and 50% when a salt stress was added. The results suggest that irrigation and salinity may regulate the production of bioactive compounds in quinoa, influencing its nutritional and industrial values.
Asunto(s)
Chenopodium quinoa/química , Chenopodium quinoa/crecimiento & desarrollo , Fenoles/análisis , Saponinas/análisis , Semillas/química , Semillas/crecimiento & desarrollo , Estrés Fisiológico , Riego Agrícola/métodos , Antioxidantes/análisis , Cinamatos/análisis , Sequías , Flavonoides/análisis , Italia , SalinidadRESUMEN
The oxidative characteristics of three different egg coproducts, namely, pasteurized eggs obtained from hens bred with organic methods (POE), pasteurized eggs from conventional breeding (PCE) and pasteurized spray-dried eggs (SPCE) obtained from conventional breeding, were analyzed. SPCE samples showed the highest content of peroxide (PV) and cholesterol oxides (COPs). In contrast, pasteurized eggs from organic breeding had the lowest index of oxidation. The three egg coproducts were used to produce dried egg pasta (spaghetti). The spaghetti was stored for 12 months at room temperature using typical pasta packaging (polypropylene foil) both under light, typical of retail conditions, and in the dark. Peroxide values and cholesterol oxidation were monitored at time 0 and then quarterly for 12 months. The oxidative parameters were significantly different in various egg coproducts, but the peroxide values of pasta were in the range of 3.0-3.5 mequiv of O(2)/kg of fat, with no differences in the types of pasta prepared with the various egg coproducts. Samples stored in the dark did not show any significant variations in peroxide values. However, PCE, SPCE and POE spaghetti stored in typical packaging increased the PV by 742.8, 846.7 and 625.7%, respectively. The pasta at time 0 showed COP values of about 50 microg of COPs/g of fat. During storage, COP values increased significantly. PCE, SPCE and POE spaghetti stored in the dark showed a content of total cholesterol oxides that was 2.0, 2.0, and 1.5 times lower than that of samples stored with typical pasta packaging.
Asunto(s)
Colesterol/química , Carbohidratos de la Dieta/análisis , Huevos/análisis , Manipulación de Alimentos/métodos , Animales , Cruzamiento , Pollos , Femenino , Masculino , Oxidación-ReducciónRESUMEN
Dietary plant sterols have received increasing attention in recent years due to their favorable health benefits. The present research focused on quantification of phytosterols as free, esterified and total forms in different tetraploid (5 cultivars of Triticum durum Desf., 9 cultivars of Triticum dicoccon Schrank) and hexaploid (5 cultivars of T. aestivum L., 12 cultivars of Triticum spelta L.) wheats. Tetraploid wheats showed the highest content of total sterol (79.4 and 79.5 mg of sterols /100 g dry weight for T. durum and T. dicoccon, respectively). Hexaploid cultivars were the best source of esterified sterols (40.7% and 37.3% of total sterols for Triticum aestivum and T. spelta, respectively). Significant amounts of free sterols (65.5% and 60.7% of total sterols for T. durum and T. dicoccon, respectively) were found in the tetraploid cultivars. The most abundant phytosterol in all wheat samples was sitosterol accounting for 45.1-59.1, 46.6-57.4 and 38.6-59.5% of total, free and esterified sterol fraction, respectively. These results demonstrate that although the sterol profile present in tetraploid and hexaploid wheat species is the same, differences in their relative amounts and distribution allow statistical differentiation between hexaploids and tetraploids, and between soft and durum wheats.
Asunto(s)
Fitosteroles/análisis , Triticum/química , Triticum/genética , Cromatografía de Gases , Esterificación , Genotipo , Fitosteroles/aislamiento & purificación , Ploidias , Semillas/química , Especificidad de la EspecieRESUMEN
Fatty acid steryl esters (FASE) in whole meal of 14 genotypes of tetraploid wheats (Triticum dicocconand T. durum) and 17 genotypes of hexaploid wheats (T. spelta and T. aestivum) were analyzed using different chromatographic strategies. By both GC-FID and HPLC-ELSD, tetraploid wheats are lacking two major peaks. The amounts of FASE, calculated on the basis of the GC-FID analysis, were double in hexaploid species as compared to tetraploids (40 and 20 mg/100 g db, respectively). HPLC with ESI-MS detection enabled the identification of FASE by the characteristic fragmentations and ion-adducts of each molecule. The distribution of steryl residues was not different between the wheat species: the main class of steryl derivatives found was the beta-sitosteryl derivatives, followed by campesteryl derivatives with small amounts of stigmasteryl esters. The esterified fatty acids explain the difference between the hexaploid and tetraploid wheats. In particular, small amounts of campesteryl and beta-sitosteryl, while no trace of stigmasteryl palmitates, were found in T. durum or its hulled ancestor T. dicoccon. Steryl oleates were not detectable in T. aestivum or its hulled ancestor T. spelta, which is consistent with the filogenesis of tetraploid and hexaploid species. Both chromatographic techniques (GC and HPLC) showed that FASE are useful to discriminate between hexaploid and tetraploid wheats from both qualitative and quantitative points of view.
Asunto(s)
Cromatografía/métodos , Ésteres/análisis , Ácidos Grasos/análisis , Fitosteroles/análisis , Triticum/química , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Genotipo , Ploidias , Semillas/química , Espectrometría de Masa por Ionización de Electrospray , Triticum/genéticaRESUMEN
Free sterols from hexaploid and tetraploid free-threshing wheats (Triticum aestivum L. and T. durum Desf.) and from their respective hulled wheats (T. spelta L. and T. dicoccon Schrank) were analysed by gas chromatography with mass spectrometry. The qualitative analysis of sterols showed a similar pattern either between hexaploid (T. aestivum, T. spelta) and tetraploid (T. durum, T. dicoccon) wheats or between free-threshing (T. aestivum, T. durum) and hulled (T. spelta, T. dicoccon) wheats. However, quantitative differences were found between tetraploid and hexaploid wheats, in that free sterol amounts in tetraploid wheats were 40% higher than in hexaploid ones. The mass spectra of the sterols were classified into four groups, taking into account the structural features of rings A and B. Typical mass spectral fragmentations of the four classes, and additional evidence related to the side chain of each molecule, were investigated together with their chromatographic behaviour, allowing identification of all the detected sterols.