首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The content of campesterol, stigmasterol, and β-sitosterol in raw and cooked Big Flint Maize (BFM), Pop Corn Maize (PCM) and Red Maize (RM) were analyzed by using a chemical method and using in vitro digestion of cooked samples. RM contained 15.14, 8.36, and 72.19 mg/100 g campesterol, stigmasterol, and β-sitosterol, respectively, which were higher compared to in BFM and PCM. Samples cooking resulted in 6–48% increase in phytosterol content, while cooked RM had the highest phytosterol content. Using the in vitro digestion method, 44–61% reduction in phytosterol content was observed in contrast to the chemical method. The difference bioaccessible campesterol and β-sitosterol contents among varieties was insignificant, except for stigmasterol in RM. The bioaccessibility of campesterol was 44–56% higher than those of stigmasterol and β-sitosterol, and it was higher in BFM and PCM. In conclusion, phytosterol contents estimated in different maize samples using in vitro digestion can be another determinative for the ultimate content and reveals the necessity to consider with chemical method of determination.  相似文献   

2.
Aadun and kokoro were produced from maize grains by processes involving roasting, kneading, spicing, and frying. Aadun with a moisture content (MC) of 12.5%, pH 5.3 had the following composition: crude protein, 7.49%; fat, 28.5%; total carbohydrate, 60.0%; ash, 3.0% and energy value, 3,600 kcal/kg whilst kokoro with a MC of 16% and pH 5.1 had, respectively: 6.42%; 22.9%; 66.6%; 2.84% and 3,550 kcal/kg. Whilst aadun and kokoro stored under ambient conditions (28±2°C; 75–80% RH) became mouldy within 7 days, samples treated with 1% butyl paraben did not develop off-colour and mouldiness.  相似文献   

3.
The ‘push–pull’ technology is a novel pest management strategy developed for control of stemborers and striga weed, Striga hermonthica, in maize-based farming systems in eastern Africa, where maize is intercropped with desmodium, a forage legume, and Napier grass is planted as a border crop. Desmodium repels stemborer moths while Napier grass attracts them. Desmodium also suppresses the parasitic striga weed through a series of mechanisms ranging from shading to allelopathy through the root system. The technology is currently being disseminated among smallholder farmers in eastern Africa and adoption rates are rising. Our on-station studies have reported efficacy of this technology against the two pests resulting in increased grain yields. The current study was conducted between 2003 and 2006 in 14 districts in western Kenya to assess effectiveness of the technology under farmers’ own conditions. Twenty farmers from each district, who had adopted the technology, were randomly selected for the study. Each farmer had a set of two plots, a ‘push–pull’ and a maize monocrop. Seasonal data were collected on percentage of maize plants damaged by stemborers, the number of emerged striga, plant height and grain yields. Similarly, farmers’ perceptions on the benefits of the technology were assessed using a structured questionnaire. Stemborer damage and striga counts to maize plants were significantly lower in the ‘push–pull’ plots than in the maize monocrop plots. Similarly, maize plant height and grain yields were significantly higher in the former. Farmers rated the ‘push–pull’ technology significantly superior in having reduced stemborers and striga infestation rates and increased soil fertility and grain yields. These results demonstrate that the technology is equally effective in controlling both pests with concomitant yield increases under farmers’ conditions in the districts studied.  相似文献   

4.
Many studies have focused on research about impact of time and density of sowing on the agronomic characteristics of different crops. However, the number of studies investigating such a response on the qualitative composition of different types of winter oilseed rape varieties is still limited. The aim of the research was to determine the effect of sowing date and density on yield, protein and oil content and quality of winter oilseed rape varieties: open-pollinated, a typical hybrid of traditional type of growth and a new semi-dwarf hybrid, which biology and yielding have not been thoroughly established. This experiment was conducted applying four sowing dates (August 14, August 25, September 4, September 15), three winter oilseed rape cultivars (PR45D03 -semi-dwarf hybrid, PR46W31 – hybrid, Californium – open-pollinated) and four sowing rates (30, 40, 50, 60 seeds/m2). Among the compared sowing dates, August 25 proved to be optimal for yielding of the tested winter oilseed rape cultivars. Semi-dwarf variety contained less protein and glucosinolate in seeds, but more oil in comparison to other studied varieties (hybrid and open-pollinated). The yields did not differ significantly within a density of 40, 50, 60 seeds/m2, so it is important result, especially for the agricultural practice.  相似文献   

5.
The objective of this study was to determine effect of storage time, storage temperature and addition of fibre on sensory quality, state of water, microstructure and texture of bread and dough.  相似文献   

6.
The effect of supplementation of three fruits, Indian gall nut, bedda nut and gooseberry, on serum lipid levels and excretion of bile acids was investigated. Rats made hypercholesterolemic by feeding hypercholesterolemia inducing diet (HID) for a period of 30 days were used as the test model. Feeding of a dried powder of these fruits along with the HID resulted in significant (p<0.01) reduction in total cholesterol, LDL cholesterol and triglycerides. HDL cholesterol remained unchanged in groups fed gall nut and bedda nut. However, the levels were significantly (p<0.01) higher in groups fed mixed and gooseberry diets in comparison to the control diet. Excretion of bile acids was found to be significantly (p<0.01) higher in animals receiving the three fruits in combination in comparison to those receiving the individual fruits.  相似文献   

7.
Zinc deficiency is one of the most widespread micro-nutritional disorder for rice. To solve the problem, screening Zn-efficient cuivivars is an available method and understanding genotype difference of Zn efficiency and their morphological and physiological characteristics is important.  相似文献   

8.
Maize is the main crop cultivated worldwide with more than 1 billion metric tons produced annually and is one of the most relevant sources of protein for human consumption in developing countries. Proteins and peptides isolated from maize exert relevant antioxidant activity which is increased by enzymatic hydrolysis. However, there is limited information about the antioxidant potential of proteins isolated from Quality Protein Maize (QPM) varieties and their hydrolysates. The aim of this research was to determine the differences in protein profile and antioxidant activity of protein fractions and hydrolysates between a hybrid white maize (Asgrow 773) and a QPM variety (CML-502). The biophysical evaluation and the total protein quantification by Kjeldahl and fractions by ninhydrin were consistent with the changes due to the breeding process of the QPM material. The antioxidant potential of the hydrolysates obtained from albumins and globulins had a 3-fold increase in both maize varieties. The prolamins hydrolysates presented an increase of 7-fold for the normal variety and 2-fold for the QPM variety. The results of this research allow indicate that the QPM varieties are a source of antioxidant peptides and promising candidates in the search for proteins and peptides with other bioactivities.  相似文献   

9.
The effects of germination, extraction (double extraction with 70% ethanol and water at isoelectric point) and -amylase treatments of chick pea seed flours on crude protein, total carbohydrate, protein efficiency ratio (PER), biological value (BV), true digestibility (TD), net protein utilization (NPU), essential amino acid composition, in-vitro protein digestibility (IVPD) and actual amino acid indices (essential amino acid index or amino acid score) were evaluated. Crude protein content was increased (8–149%), while total carbohydrate was decreased (11–62%) by germination, extraction and -amylase treatments. Alpha-amylase treatment was more efficient in reducing total carbohydrate and increasing the protein content than that of extraction treatment. The protein quality of chick pea flours as measured by PER, BV, TD, NPU, IVPD and corrected amino acid indices (actual amino acid indices×IVPD) was significantly improved by these treatments. The protein quality of germinated--amylase treatment was comparble with casein, while germinated--amylase treaded seeds appeared nutritionally superior to casein. The results indicate that the germinated--amylase and germinated--amylase-extracted treatments could be used successfully as a source of concentrated high quality protein for baby food production. The corrected amino acid indices gave better prediction of PER, BV, TD and NPU (r=93 to 97) than actual amino acid indices (r=45 to 71). PER was highly correlated with corrected amino acid score (r=0.93). The PER could be predicted from the following simple regression equation: PER=–1.827+0.0561×corrected amino acid score.  相似文献   

10.
Plant Foods for Human Nutrition - As diets change in response to ethical, environmental, and health concerns surrounding meat consumption, fermentation has potential to improve the taste and...  相似文献   

11.
A survey of the production, consumption and storage ofKunu was carried out. Some of the information included consumption rate, processing techniques andequipment, producer's status and grains used. About73% consume Kunu daily, 26% occasionally; 1% knowit is produced but may or may not be consuming it. Millet (Pennisetum typhoideum), sorghum (Sorghum vulgare), maize (Zea mays), rice (Oryza sativa) and acha (Digitalis exilis) wereused in its production in decreasing order ofpreference. The grains were used singly or combined;sorghum/millet was the most common combination in aratio of 1:2 (w/w). Steeping was done in ordinary water for 12–72 h, depending on the grain type, in localclay pots, plastic buckets, calabashes or basins or5–7 h in warm water (60–70 °C). The grainswere dry or wet milled with or without spices such asginger, red pepper, black pepper, clove and garlic.Other ingredients introduced included: sweet potatoes,malted rice, malted sorghum and Cadaba farinosacrude extract. Both dry and wet milling was done withgrinding mills, mill stones or mortar and pestle,depending on locality. The product was then cookedinto a thin free flowing gruel. The various types ofkunu were: Kunun zaki, Kunun gyada, Kunun akamu, Kununtsamiya, Kunun baule, Kunun jiko, Amshau and Kunungayamba. Kunun zaki was the most commonly consumed. Production and consumption cut across all socialclasses of the society.  相似文献   

12.
Research on root morphological traits of dry-raised seedlings (D-RS) at different growth stages of rice have so far attracted less attention. In this study, using mid-season indica hy-  相似文献   

13.
The effect of hydration (in the range of aw 0.981–0.090) on changes of macroscopic and mechanical features of triticale snacks produced in different conditions (feed moisture - 16 and 20%; extrusion temperature - 135 and 175 °C) was analysed. Changes of snacks depended both on the hydration level and the extrusion process conditions.As a result of storage at the highest hydration level (aw = 0.981) contraction of snacks was observed. The shrinkage was more pronounced in case of extrudates obtained from raw material containing 16% of water regardless of the extrusion temperature. The hardness of extrudates depended both on the feed moisture and hydration. Samples obtained from the raw material containing 20% moisture were harder than those prepared at the feed moisture of 16%. Based on the results of molecular dynamics study by low field NMR technique, a model of hydration was developed and critical hydration value of extruded snacks was calculated. Higher values of the critical hydration were obtained for snacks extruded at temperature 135 °C than for those obtained at 175 °C. The feed moisture level affected critical hydration values to a lesser extent. Obtained results suggest that the state of water in extrudates depends on extrusion process conditions.  相似文献   

14.
Zinc deficiency is one of the most widespreadmicro-nutritional disorder for rice.To solve  相似文献   

15.
Oat malt is a nutritionally rich ingredient mainly used in a small number of speciality products. The aim of this study was to evaluate the suitability of oat malt in wheat baking. The effect of oat malt on bread and dough properties at levels ranging from 0.5% to 5% was studied and compared with barley and wheat malts. The addition of all malts increased loaf specific volumes. Barley and wheat malts at levels above 2.5% led to a sticky and coarse crumb, but the effect of oat malt on the crumb grain was negligible. Rheological characterisation could not explain the superior baking performance of oat malt, as it increased extensibility and decreased resistance extensively indicating weakening of the extensional properties of the gluten network. The high lipolytic activity may have compensated for the loss of dough strength by improving the surface properties of gas cells. The results show that oat malt can be used in wheat baking to improve the loaf volume and nutritional quality without the detrimental effects associated with the excess amylolytic activity of barley and wheat malts.  相似文献   

16.
Cereal grains contain many phytochemicals, some of which significantly influence the grain colour. Anthocyanins are accumulated in the aleurone or pericarp layer and give blue, purple or combination of these colours. Flavonoids, such as yellow C-glycosides of flavones, flavonols, flavanonols, proanthocyanidins and reddish-coloured phlobaphenes are mainly present in the outer layer of grains while carotenoids that are responsible for yellow grain are in the endosperm. Therefore, accumulation of these pigments in the grain can represent an important target in breeding programmes aimed at increasing the concentrations of bioactive components in grain and products. This review therefore summarises our current knowledge of anthocyanin and carotenoid pigments, their genetic control and variation in levels in different wheat lines.  相似文献   

17.
Oat malt is a nutritionally rich ingredient mainly used in a small number of speciality products. The aim of this study was to evaluate the suitability of oat malt in wheat baking. The effect of oat malt on bread and dough properties at levels ranging from 0.5% to 5% was studied and compared with barley and wheat malts. The addition of all malts increased loaf specific volumes. Barley and wheat malts at levels above 2.5% led to a sticky and coarse crumb, but the effect of oat malt on the crumb grain was negligible. Rheological characterisation could not explain the superior baking performance of oat malt, as it increased extensibility and decreased resistance extensively indicating weakening of the extensional properties of the gluten network. The high lipolytic activity may have compensated for the loss of dough strength by improving the surface properties of gas cells. The results show that oat malt can be used in wheat baking to improve the loaf volume and nutritional quality without the detrimental effects associated with the excess amylolytic activity of barley and wheat malts.  相似文献   

18.
Row spacing effects on light interception and extinction coefficient have been inconsistent for maize (Zea mays L.) when calculated with field measurements. To avoid inconsistencies due to variable light conditions and variable leaf canopies, we used a model to describe three-dimensional (3D) shoot structures combined with a model of 3D light transfer. The MODICA model mimics 3D shoot structures of maize plants from digitizations in the field and makes it possible to simulate associated hypothetical canopies by re-arranging plants into different row spacings. All row spacings examined with the model had 10 plants m−2. By using the light model RIRI, simulations showed the relative importance of development stage and time integration on fraction of light transmitted and on the extinction coefficient. Narrow row spacings consistently had less transmitted light and greater values of extinction coefficient. This modelling tool shows promise to effectively evaluate row spacing to optimize light interception.  相似文献   

19.
This study investigated the effects of different GM maize crops on the abundances of rove beetles. It also investigated competition between rove beetles and other epigeic arthropod predatory groups (ground beetles and spiders). Altogether a total of 5926 rove beetle individuals belonging to 25 species were collected. Whilst the average number of rove beetle individuals per replicate per sampling date varied and, moreover, decreased each year, there were no observed differences in rove beetle abundance when compared between isogenic and GM maize plots within the study period. Furthermore, no clear trends on positive correlations between weed coverage and rove beetle abundances were detected. Altogether a total number of 76,070 ground beetle individuals and 11,126 spiders (including all Araneae) were collected with pitfall traps. Analyses revealed a strong negative relationship between rove beetles and the other two groups in each treatment and year. According to the results the effect of interspecific competition on rove beetle abundance in GM maize is much higher than the effects of treatments including both Bt toxins and extra glyphosate applications.  相似文献   

20.
The brown planthopper, Nilaparvata lugens (Stal) (BPH) is one of the most important insect pests of rice in China and other east-southern Asian countries. Utilization of rice resistance varieties is one of the most e-conomic and effective ways for controlling N. lugens . The resistance of rice varieties declined due to the change of BPH biotype. The current resistance screening methods based on biotic reaction also may eliminate numerous rice varieties with high-yielding and/ or good grain quality which were not resistant to BPH but had strong tolerance to BPH.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号