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1.
The distribution of protein, ash, lutein, tocopherols and tocotrienols in the germ, bran and endosperm portions was studied in seeds of two einkorn accessions and one bread wheat. The two einkorns showed a higher content of most compounds, but the distribution within the kernel was similar in both species. The germ fraction showed the highest concentration of protein, lutein, α-tocopherol, β-tocopherol and total tocols. Ash, α-tocotrienol and β-tocotrienol levels were highest in the bran fraction, although significant quantities were detected also in the germ and, for tocotrienols, in the flour.  相似文献   

2.
The kinetics of tocols degradation in wholemeal and white flours from einkorn cv Monlis and bread wheat cv Serio were studied during storage at five different temperatures (−20, 5, 20, 30 and 38 °C) up to 242 days. Tocols decreased as a function of time and temperature, following first-order kinetics. Degradation rates and their dependence upon temperature were similar for the two Triticum species studied. Tocols decrease was quicker in white flour than in wholemeal flour (on average for total tocols at 38 °C, k = 7.79 × 10−3 days−1 vs 3.15 × 10−3 days−1, respectively). The temperature-dependent degradation was similar for all homologues (Ea = 34.3–49.4 kJ/mol) except for α-T, less thermostable in white flours (Ea = 61.2 kJ/mol in einkorn and Ea = 54.7 kJ/mol in bread wheat).  相似文献   

3.
Wheat contributes significantly worldwide to antioxidant income with beneficial healthy effects. Two varieties of einkorn wheat (Triticum monococcum L. – Escana and Schwedisches Einkorn), two varieties of wild emmer [Triticum dicoccum Schuebl (Schrank)] (Rudico and Kahler Emmer) and three varieties of spring wheat (Triticum aestivum L. – Granny, Kärtner Früher and SW Kadrilj) were evaluated for tocols – tocopherols and tocotrienols by high performance liquid chromatography – electrospray ionisation tandem mass spectrometry (HPLC–ESI/MS/MS). Investigated emmer and einkorn wheat varieties have shown minor lower total tocols content in comparison with spring varieties, however significant typical levels of tocopherols and tocotrienols were found in these groups. In einkorn wheat varieties the major abundance of total tocols is represented by tocotrienols (Schwedisches Einkorn 65.0%, Escana 54.9%), in emmer wheat varieties the abundance of tocotrienols and tocopherols were similar (Rudico 48.9% of tocotrienols, Kahler Emmer 47.6%), whereas in spring bread wheat higher tocopherols (SW Kadrilj 54.5%, Kärtner Früher 60.2%, Granny 55.0%) were recorded.  相似文献   

4.
The effects of various thermal processing treatments (blanching, boiling and steaming) of red cabbage, Brassica oleracea L. ssp. capitata f. rubra cv. ‘Autoro’, were assessed for the levels of glucosinolates (GLS), total phenols (TP), total monomeric anthocyanins (TMA), l-ascorbic acid (L-AA) and soluble sugars, as well as for the antioxidant potential by the ferric reducing ability power (FRAP) and oxygen radical absorbance capacity (ORAC) assays. Individual native GLS were determined by ion-pair HPLC-MS/DAD. There were significant (p < 0.05) losses in blanched red cabbage: TP, 43%, TMA 59%, FRAP 42%, ORAC 51%, L-AA 48% and soluble sugars 45%. Boiling gave less extensive reductions: TP 16%, TMA 41%, FRAP 17%, ORAC 19%, L-AA 24% and soluble sugars 19%. Steaming caused no losses for TP, ORAC, FRAP or soluble sugars. However, significant reductions were found for TMA and L-AA, with 29% and 11%, respectively. In general losses were accounted for in the processing waters; however, TMA was not fully recovered, indicating degradation. Total GLS were severely affected by processing, with reductions of 64%, 38% and 19% in blanched, boiled and steamed red cabbage, respectively. Total aliphatic and indole GLS were similarly affected. Lost GLS were partially recovered in the processing water.  相似文献   

5.
The comparative effects of steaming and gamma irradiation on the physicochemical and microbiological properties of dried red pepper (Capsicum annum L.) were investigated during post-treatment storage at refrigerated (4 ± 2 °C) and room (20 ± 2 °C) (RT) temperatures for 6 months. Whole dried peppers were either steamed, hot air-dried and processed into powder form or powderised, packed in PE bags and gamma-irradiated at 10 kGy. The commercial steam treatment led to a 1- to 2-log reduction in the initial microbial load (106 CFU/g) accompanied with changes in spice as indicated by low Hunter’s colour values and reduced sensory scores in RT-stored samples. However, irradiation resulted in a 5-log reduction with minimal effects on the physicochemical properties, except for the decreased content of capsanthin in the irradiated samples. The functional components of spices were not apparently affected by both treatments. The refrigerated storage following irradiation is recommendable for powdered red pepper to minimise physicochemical changes.  相似文献   

6.
Fruit of wolf (Solanum lycocarpum A. St. - HILL), found in Brazilian cerrado, has been used in the initial ripening stage as flour and/or starch in popular medicine due to its hypoglycemiant action. The aim of this work was to study the occurrence of phytochemical compounds, physical, chemical and technological characteristics of fruit of wolf flour and starch in the initial ripening stage. Flour and starch were extracted using known popularly and experimental methods (with sodium bisulfite) and chemical composition and technological characteristics were analyzed. The results were comparatively assessed by Tukey's test (p < 0.05). The recommendation for use was the extraction of flour and starch products by previously removing peels and seeds of fruit of wolf. The most relevant finding in this study is the high content of fibers in flour (23 g/100 g) and high content of resistant starch (32 g/100 g) in the fraction of starch extracted from fruit of wolf, which can explain their use as hypoglycemic agent.  相似文献   

7.
Partial substitution of wheat flour (Triticum aestivum) with vetch flour (Lathyrus sativus L) at the levels of 5, 10, 15 and 20 g/100 g was carried out to determine its influence on physico-chemical, rheological, nutritional and sensory characteristics of composite flour doughnuts. Commercial wheat variety, Inqlab-91 was found suitable for the preparation of doughnuts. Sensory and objective evaluations (weight, volume and specific volume) of doughnuts were carried out to evaluate the acceptability of doughnuts. Protein, lysine and trypsin inhibitor contents increased significantly (P<0.05) from 12.10 to 13.84 g/100 g, 2.46-3.58 g/100 g protein and 173 to 187 TIU/g on increasing the level of vetch flour from 0 to 15 g/100 g in the doughnuts, respectively. In vitro protein digestibility of doughnuts was also found to increase (71.8-76.3 g/100 g). It was inferred that doughnuts supplemented with vetch flour up to the level of 15 g/100 g were sensorily acceptable.  相似文献   

8.
Five different varieties of cauliflower (Brassica oleracea L. ssp. botrytis); two white (cv. ‘Aviso’, ‘Dania’), one purple (cv. ‘Grafitti’), one green (cv. ‘Emeraude’) and one romanesco/green pyramidal (cv. ‘Celio’) cultivar have been studied. All samples were thermally processed and the effects on the levels of glucosinolates (GLS), total phenols (TP), total monomeric anthocyanins (TMA), l-ascorbic acid (l-AA) and antioxidant capacities (FRAP and ORAC) were investigated. Processing methods applied were: blanching (3 min), boiling (10 min) and steaming (10 min). Total GLS were significantly (p < 0.05) affected by processing with the highest losses, 55 and 42% on average, occurring for boiled and blanched samples, respectively. Significant effects were also noted for steaming, but to a lesser extent, i.e. 19% average reduction. Antioxidant-related parameters were similarly affected with average losses of 27, 33, 36 and 46% in boiled cauliflower and 16, 21, 22 and 28% in blanched for TP, FRAP, l-AA and ORAC, respectively. Blanching and boiling reduced TMA in purple cauliflower by 38 and 53%, respectively. Steaming affected the antioxidant-related parameters the least for all cultivars. l-AA was significantly reduced by 14% in all cultivars by steaming. Some differences in behaviour between cultivars were noted, especially between white and coloured cultivars for TP, FRAP and l-AA, but also for some GLS. The main losses were caused by leaching into the processing water.  相似文献   

9.
The effect of varying sowing time on wheat flour protein quality and starch pasting characteristics was studied in two genotypes differing in their water requirements for two years under irrigated and rain-fed conditions. Delayed sowing associated with high temperature during grain filling resulted in an overall increase in total grain protein. Low temperature prevailing under early sown conditions enhanced insoluble glutenin (IG) but reduced total protein accumulation in both the genotypes. IG and residue proteins increased but soluble glutenin and amylose decreased under rain-fed conditions. Amylose, hold- and final viscosity (FV) increased but setback decreased with change in normal sowing time. Peak viscosity (PV) increased under late sown conditions. Pasting temperature, setback, FV and breakdown (BD) were enhanced under rain-fed conditions. This study inferred that by selecting suitable irrigation practices and different sowing times for subjecting the crop to desirable temperature range, flour properties of given cultivars can be manipulated.  相似文献   

10.
Broccoli develops a fast senescence that deteriorates the nutritional quality of the product. In this work, a combined treatment with hot air and UV-C were applied to minimally processed broccoli florets to investigate their effects on the antioxidant system during storage at 20 °C. Application of UV-C and heat enhanced by approximately 13% the levels of total antioxidants immediately after treatment. These levels were lower than initials in both control and treated samples. Nevertheless, higher values (ranged from 12 to 50%) were also detected in treated samples during storage. In general, higher values of antioxidants were correlated with elevated levels of phenols (from 10 to 17%) and ascorbic acid (from 11 to 17%) in treated florets. The increment in the content of phenolics in treated broccolis was correlated to an increased phenylalanine ammonia lyase (PAL) activity. The combined treatment also affects the activity of enzymes involved in removal of reactive oxygen species. An increase of about 50% in superoxide dismutase activity was detected after treatment. During the first days of storage this higher activity was about 40%. Enzymes that remove H2O2 like catalase and ascorbate peroxidase showed an enhanced activity toward the end of storage. The combined treatment diminished the peroxidase (POX) activity approximately 60% after the treatment and near 50% after two days of storage, suggesting a minor role of this enzyme in detoxification of H2O2. In conclusion, combined treatment may contribute to enhance the protection against oxidative molecules not only by increasing levels of phenolics and ascorbic acid but also by enhancing the activity of enzymes involved in removing reactive oxygen species.  相似文献   

11.
Seed characteristics and nutrient composition of three morphotypes of big-grained Mucuna urens (L.) Medikus were studied. Results showed that 100-seed weight ranged from 3200.2 to 4700.9 g, cotyledon weight per seed (23.2–26.6 g) and testa weight per seed (9.0–21.2 g). The testa constituted 43.7%, 28.1% and 44.7% of the average seed weight for morphotypes 1, 2 and 3, respectively. The cotyledon also constituted 56.3%, 71.9% and 55.3% of the average seed weight for morphotypes 1, 2 and 3, respectively. Nutrient composition analyses showed that the three morphotypes of M. urens are good sources of crude protein (19.97–20.57 g 100 g−1), carbohydrate (72.39–75.49 g 100 g−1) and fat (1.84–5.05 g 100 g−1). Other nutritional components, including ascorbic acid, calcium and phosphorus are present in the three morphotypes in moderate amounts. The iron content of the M. urens is low. The three morphotypes contain appreciable amounts of essential amino acid. The oxalate content is low. The variations observed in the seed characteristics and nutrient compositions are suspected to be due to genotype. Genetic improvement of this plant is recommended to remove the itching hair trait so as to encourage its cultivation.  相似文献   

12.
13.
The aim of this study was to compare some of the properties of native and extruded amaranth flour obtained under mild and severe extrusion conditions. The chemical composition of the flours was similar. Flours obtained by both extrusion processes presented high solubility in water, low values of L∗ (luminosity) and an absence of endothermic peak on the DSC method. Water absorption, retrogradation tendency, final viscosity and the viscous behavior by rheology analysis were also studied. The results indicate that extruded flours have a good potential as an ingredient for food exposed to heat treatment at a high temperature and mechanical shear, for use in instant meal products. On the other hand, original flour properties are comparable to those of amaranth starch, which exhibits similarly high quality paste stability, low solubility in water, and elastic behavior, and could be used as a substitute for raw flour in a range of food formulas.  相似文献   

14.
Glucosinolate (GSL) and antioxidant activity in 62 varieties of Chinese cabbage (Brassica rapa L. ssp. pekinensis) were determined by HPLC and DPPH, HRSA, and FRAP assays. Five aliphatic GSLs: progoitrin, sinigrin, glucoalyssin, gluconapin, and glucobrassicanapin; four indolyl GSLs: 4-hydroxyglucobrassicin, glucobrassicin, 4-methoxyglucobrassicin, and neoglucobrassicin; one aromatic GSL: gluconasturtiin were identified. Glucobrassicanapin and gluconapin documented the most abundant (average 4.52 and 3.72 μmol/g DW, respectively). The contents of total GSLs varied extensively among 62 varieties (range from 2.83 to 48.53 μmol/g DW). Comprehensive differences in total and individual GSL contents have also been observed among different varieties. Indolyl and aromatic GSL together accounted 26% of the total GSLs; but there are few differences among varieties. FC7 and FI17 could be good candidates for future breeding programs since they had a high quantity of glucobrassicin (2.10 and 1.66 μmol/g DW, respectively). Most of the Chinese cabbage varieties showed significant antioxidant activities when compare with positive control. However, three antioxidant assays were not significantly correlated with total GSLs. The presence of significant quantities of glucobrassicin in some varieties should be studied more extensively, since GSL is the precursor of indole-3-carbinol, a potent anticancer isothiocyanate.  相似文献   

15.
Defatted bran of dark blue grained wheat (Triticum aestivum L., cv. Hedong Wumai) was extracted using ethanol and chemically characterized by HPLC and ESI-MS. Cyanidin-3-glucoside was the predominant anthocyanin in the pigmented wheat which also contained cyanidin-3-galactoside, pelargornidin-3-glucoside, and peonidin-3-glucoside. Ferulic acid was identified as the major simple phenolic acid, with lesser amounts of p-hydroxybenzoic acid, caffeic acid, syringic acid and p-coumaric acid also present. Anthocyanins were separated from phenolic acids using solid phase extraction, and respective fractions were determined for DPPH radical, ABTS radical scavenging tests as well as oxygen radical absorption assay. Results showed that 69% of the overall free radical scavenging capacity of dark blue grained wheat was attributed to the anthocyanin content, compared to 19% for the extractable phenolic acids. In cell based models, the pigmented wheat extract significantly suppressed both hydrogen peroxide-induced intracellular oxidation (p < 0.01) and bacterial lipopolysaccharide-induced nitric oxide (p < 0.05) production. These data report for the first time the major phytochemical composition of pigmented grained wheat and associated bioactivity towards free radical scavenging and suppression of ROS and RNS activity.  相似文献   

16.
In order to evaluate the effects of heat treatment on the quality of postharvest bamboo shoots, the firmness, disease incidence, respiration and ethylene production, ACC synthase (ACS) and ACC oxidase (ACO) activities, lignin and cellulose contents, and the activities of phenylalanine ammonia-lyase (PAL), cinnamyl alcohol dehydrogenase (CAD) and peroxidase (POD) were examined during storage at 20 °C after heat treatment at 45 °C for 5 h. Heat treatment inhibited disease incidence and respiration, retarded ethylene production, and decreased ACS and ACO activities in bamboo shoots. Furthermore, heat treatment significantly delayed the rise in the activities of PAL, CAD and POD, which were associated with the inhibition of the synthesis of lignin and the delayed tissue lignification. These findings suggest that heat treatment could be a potential tool to delay lignification and decrease disease incidence in bamboo shoots during storage at 20 °C.  相似文献   

17.
Eleven blackcurrant cultivars grown with pesticide (PT) and without pesticide treatment (PF) were evaluated to compare the differences in plant growth and physical condition, total anthocyanin content, ascorbic acid content, total antioxidant capacity, effect on prostaglandin E2 (PGE2) production and anticancer cell proliferation activities. Results showed that the yield and growth of PT blackcurrants were higher. However, PF blackcurrants contained a higher amount of ascorbic acid, and displayed an increased inhibition against cancer cells compared to PT blackcurrants, indicating that PF blackcurrants have an increased potential to deliver health-promoting benefit for consumers. Significant differences were observed between blackcurrant cultivars in relation to plant growth and physical condition, total anthocyanin content and PGE2 assay, highlighting the importance of cultivar selection.  相似文献   

18.
Glucosinolates are a group of secondary plant metabolites that are found in the Brassicaceae family. Upon hydrolysis by the endogenous enzyme myrosinase, a large number of compounds can be formed of which some are potentially anticarcinogenic, while others are largely inactive. Furthermore, some bioactive compounds are unstable. Therefore, it is not only important to determine the type and amount of glucosinolates present or hydrolysed in a given plant, but it is also relevant to investigate the type of hydrolysis products. In this research, the effect of combined pressure–temperature treatments (100–500 MPa, 20–40 °C) on the glucosinolate conversion and the kind of hydrolysis products was studied in broccoli, both during treatment and after autolysis. The results, showed that high pressure can induce glucosinolate hydrolysis during treatment, promote the formation of isothiocyanates after treatment and that relatively more indole oligomers are formed during treatment than during autolysis. These results indicate that pressure treatment limits the loss of glucosinolates and its health beneficial products.  相似文献   

19.
The rheological performance of pectin-enriched products extracted from red beet (Beta vulgaris L. var. conditiva) root by-products was evaluated in the present work. They were extracted through an alkaline pre-treatment with or without a subsequent enzymatic (hemicellulase or cellulase) hydrolysis at pH 5.2. Flow assays performed with 2.00% w/v-pectin aqueous systems showed pseudoplastic (flow index, n ≈ 0.4 or 0.8) or Newtonian (n = 1.0) behaviour after fitting of experimental data to Ostwald’s law, also showing poor thickening effect. When Ca2+ was added to water with the same pectin concentration, true gels developed as confirmed by the mechanical spectra obtained through dynamic assays. Junction zones of homogalacturonan (HG) side chains mediated by Ca2+ were able to build up rigid networks in water.Isolated pectins (2.00% w/v) were also used to constitute milk model systems. Whole and skimmed milk were used at two different concentrations. Milk systems showed more transient and weaker gel networks when compared to Ca2+-aqueous systems, and were associated to the formation of a [κ-casein?calcium cross linked low methoxyl pectin] complex dampened by the included milk fat globules. Relaxation spectra of pectin-milk systems were in general extended to large relaxation times (104 s) for all isolated fractions studied, which is typical of structured systems. Since all pectin fractions showed very similar chemical composition and molecular weight (average value and distribution), it was suggested that some differences in the rheological performance of each pectin product came from the different length of arabinans and distribution of rhamnose kinks (RG-I, random coil) as well as from the length of demethylated HG chains (semi-flexible coils).The results of this research show that the pectin-enriched fractions isolated from red beet root wastes are useful as additives in food formulation.  相似文献   

20.
Arbutus unedo is a widespread shrub with economic importance, derived from the use of its berries in the production of alcoholic beverages and in folk medicine. This work intends to evaluate for the first time the effect of fruit ripening stage on antioxidant activity, total phenolic content, fatty acid profile and tocopherol composition. Ripe fruits shown higher extraction yield (45.04 ± 2.23%) when compared to other fruit ripening stages. By contrast, total phenol contents were higher in the unripe and intermediate stage of ripeness (108 and 111 mg GAES/g dry fruit, respectively, against 60 mg/g dry fruit when ripe). Ripe and intermediate fruits shown the lower EC50 values on the DPPH radicals (0.25 ± 0.02 mg/mL) and reducing power assay (1.09 ± 0.05 mg/mL), respectively. A significant correlation was established between antioxidant activity and fruits ripening stage. Fatty acid profiles were very similar between the ripening stages, being alfa-linolenic, linoleic and oleic, the three major ones. Polyunsaturated fatty acids (PUFA) represent as much as 60% of the total fatty acids, with a highly favorable omega 3/omega 6 ratio. From the analysis of the vitamin E vitamers, the most important was ??-tocotrienol, with a clear reduction in the total free vitamin E content with ripening.These results highlight that the fruits of intermediate ripeness can be regarded important sources of biologically active compounds with a fatty acid profile rich in omega-3 PUFA, properly supplemented with high vitamin E amounts.  相似文献   

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