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Tracey Jones Ruth Feber Gabriel Hemery Paul Cook Katy James Curt Lamberth Marian Dawkins 《Agricultural Systems》2007
The commercial, welfare and environmental impacts of rearing small colonies of free-range chickens in newly planted woodland at two sites in the UK, during the first 2 years of the enterprise, were investigated. Newly planted rather than established trees were used so that commercially viable species could be planted in a way that would suit the management of the chicken enterprise, and small colonies were used so that farmers wishing to diversify could buy into the system progressively. It was anticipated that marketing a high specification product would provide an immediate income, whilst waiting for the future investment in trees to grow. 相似文献
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Tanja Nurmi Anna-Maija Lampi Laura Nyström Youna Hemery Xavier Rouau Vieno Piironen 《Journal of Cereal Science》2012
Phytosterols and steryl ferulates are bioactive compounds accumulating in the bran and germ of wheat. However, little is known regarding their localisation and composition in the bran layers of the kernel. The aim of this study was to determine the distribution of phytosterols and steryl ferulates in the wheat grain and in the different layers of bran. The wheat fractions, produced by conventional debranning, aleurone separation and a novel electrostatic process, were analysed for phytosterol contents using GC–FID and for steryl ferulate contents using HPLC–UV. The compounds were identified by GC– and LC–MS. Phytosterols and steryl ferulates were concentrated in the bran layers. The steryl ferulates were accumulated in the intermediate layers, whereas the phytosterols were more evenly distributed in the intermediate layers and aleurone cell contents. The phytosterol composition varied within the wheat kernel, while the steryl ferulate composition was similar in different fractions. Sitosterol and campestanyl ferulate were the main compounds. The highest levels of phytosterols (up to 2117 μg/g) and steryl ferulates (up to 703 μg/g) were found in the pearling, aleurone and certain bran fractions. The phytosterol-rich fractions could be utilised in cereal foods to enhance the intake of health-promoting compounds from natural sources. 相似文献
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Data from a trial of 36 families at Little Wittenham, North Oxford was used to assess growth traits and stem form in common
ash (Fraxinus excelsior, L.). The trial followed a design described by Barnes (Silv Genet 44(2–3):81–88, 1995) as the Breeding Seedling Orchard (BSO).
The objectives of the study were to determine variation in growth and form traits and estimate genetic parameters of families.
Assessments conducted at 3–8 years for height, diameter at breast height (dbh), straightness and forking showed significant
differences (P < 0.05) among families with Guys (19), Settrington (34), Overbury (23) and Grimthorpe (36) being the best performers while
Coleford (3 and 5) Gwynedd (27) and Bacheiddon (32) were the least performers. At the overall level, the additive genetic
coefficient of variation (CVA) ranged between 10.2 and 12.7% for height and 1.5 and 2.1% for dbh. Height had a high genetic correlation (rg = 0.85) with dbh whilst forking had low correlation (rg = 0.25) with height. Estimates of heritability decreased with age from
= 0.62 at 3 years to = 0.30 at 8 years for height while values for dbh decreased from = 0.48 at 4 years to = 0.27 at 8 years. Some genetic gains are possible despite the low genetic variation among families; height had the greatest
potential of genetic gain (12.5% at 8 years). Results suggest that early selection of superior families of Fraxinus excelsior appears to be feasible and it could be possible to achieve simultaneous improvement in both growth and form. 相似文献
4.
Investigating agroforestry systems that incorporate poultry is warranted in Northern Europe as they may offer benefits including: improved welfare and use of range; reduced feed costs; price premia on products; reduced payback periods for forests; and, greater returns on investment. Free-range egg production accounts for 27% of the United Kingdom egg market and demand for outdoor broilers is increasing. No research has been conducted recently on the economic viability of agroforestry systems with poultry. An economic model was constructed to: assess economic viability of a broiler agroforestry system; and, investigate the sensitivity of economic performance to key factors and interactions, and identify those which warrant attention in research and management. The system modelled is a commercial trial established in Southern England in 2002 where deciduous trees were planted and broilers reared in six- or nine-week periods. The model uses Monte Carlo simulation and financial performance analyses run for a 120-year period. An Internal Rate of Return (IRR) of 15.5% is predicted for the six-week system which remains viable under a ‘worst case’ scenario (IRR of 12.6%). Factors which affect financial performance most (decreasing in magnitude) are prices achieved for broilers, costs of brooding houses, chicks, arks, feed and timber prices. The main anticipated effects of biological interactions on financial performance (increased ranging on feed conversion and excess nutrient supply on tree health) were not supported by analysis. Further research is particularly warranted on the welfare benefits offered by the tree component and its relation to price premia. 相似文献
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Potential of dry fractionation of wheat bran for the development of food ingredients,part I: Influence of ultra-fine grinding 总被引：1，自引：0，他引：1
Youna Hemery Marc Chaurand Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Vieno Piironen Abdelkrim Sadoudi Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is an undervalued by-product of white flour and has great nutritional potential due to its high content in fibres and bioactive compounds. Micronized bran could be used as a food ingredient to improve the nutritional potential of cereal products, or be used as a starting material for other processes (bioactive compound extraction or bran fractionation). The aim of this work was to find a way to efficiently decrease the particle size of bran. The influence of the grinding temperature (ambient or cryogenic grinding) on the granulometric distribution of particles, their composition, and their microstructure was studied, at lab-scale and pilot-scale. It showed that the intrinsic characteristics of bran (glass transition within intermediate layers at −46 °C) had more influence on its grinding behaviour than the type of grinding device used: the particles size distributions obtained after grinding at lab-scale and pilot-scale were very similar. At both scales, the granulometric curves were narrow for cryogenic grinding, while for ambient grinding they were spread over the whole particle size range. Ultrafine particles were obtained in both ambient and cryogenic conditions. Negative temperatures, by increasing the material’s brittleness, favoured a fast fragmentation of bran: one step of cryogenic grinding allowed a median particle size of nearly 50 μm to be reached, whereas three successive steps of ambient grinding were needed for the same result. On the other hand, ambient temperature favoured the dissociation of the different constituent layers of wheat bran, and produced less composite particles than cryogenic grinding. 相似文献
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Youna Hemery Valérie Lullien-Pellerin Xavier Rouau Joël Abecassis Marie-Françoise Samson Per Åman Walter von Reding Cäcilia Spoerndli Cécile Barron 《Journal of Cereal Science》2009
To produce safe and healthy whole wheat food products, various grain or bran dry fractionation processes have been developed recently. In order to control the quality of the products and to adapt these processes, it is important to be able to monitor the grain tissue proportions in the different milling fractions produced. Accordingly, a quantitative method based on biochemical markers has been developed for the assessment of grain tissue proportions in grain fractions. Grain tissues that were quantified were the outer pericarp, an intermediate layer (including the outer pericarp, the testa and the hyaline layer), the aleurone cell walls, the aleurone cell contents, the endosperm and the germ, for two grain cultivars (Tiger and Crousty). Grain tissues were dissected by hand and analysed. Biochemical markers chosen were ferulic acid trimer, alkylresorcinols, para-coumaric acid, phytic acid, starch and wheat germ agglutinin, for outer pericarp, intermediate layer, aleurone cell walls, aleurone cell contents, endosperm and germ respectively. The results of tissue quantification by hand dissection and by calculation were compared and the sensitivity of the method was regarded as good (mean relative errors of 4% and 8% for Crousty and Tiger outer layers respectively). The impact of the analytical variability (maximum 13% relative error on coarse bran) was also regarded as acceptable. Wheat germ agglutinin seems to be a promising marker of wheat germ: even if the quantification method was not able to quantify the germ proportions in milling fractions, it was able to classify these fractions according to their germ content. The efficiency of this method was tested, by assessing the grain tissue proportions of fractions exhibiting very different compositions such as flour, bran and aleurone-rich fractions obtained from three different grain or bran dry fractionation processes (conventional milling, debranning process, production of aleurone-rich fractions from coarse bran). By calculation of the composition of the different products generated, it was possible to study the distribution of the different tissues among fractions resulting from the different fractionation processes. This quantitative method is thus a useful tool for the monitoring and improvement of processes, and allows the effects of these processes to be understood and their adaption to reach the objectives. 相似文献
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Dry processes to develop wheat fractions and products with enhanced nutritional quality 总被引：2，自引：0，他引：2
Youna Hemery Xavier Rouau Valrie Lullien-Pellerin Ccile Barron Joël Abecassis 《Journal of Cereal Science》2007,46(3):327
Numerous epidemiological studies have investigated the potential health benefits of consuming more wholegrain foods. However, in Europe, most wheat-based food products are made with refined endosperm from which the germ and peripheral layers (bran) are excluded, although these tissues have considerable nutritional potential and contain most of the micronutrients, phytochemicals and fibre of the grain. Dry fractionation technologies allow these peripheral tissues to be separated and recovered to efficiently separate valuable from detrimental components (i.e. contaminants, antinutrient compounds, irritants), in order to develop nutritionally enhanced ingredients and products. The rational development of efficient processes requires the ability to monitor the fractionation and understand the fate of grain tissues, and to take into account the various properties of the different parts of the grain in order to design an appropriate fractionation protocol. This review provides an overview of the existing processes that can be used for the production of wheat products and fractions with enhanced nutritional interest. The grain composition and properties are briefly introduced with emphasis on nutritionally interesting compounds. Tissue markers and their application in process monitoring are presented, and the physical properties that influence the fractionation properties of grain tissues are developed. The main wheat dry fractionation processes are then reviewed, including pretreatments, degerming, debranning, and bran fractionation. 相似文献
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Martijn W.J. Noort Daan van Haaster Youna Hemery Henk A. Schols Rob J. Hamer 《Journal of Cereal Science》2010
The nature of the adverse effects of wheat bran fractions on bread-making quality was studied. Two fractions of bran, representing different tissue layers and having different compositions, were used. The particle size of the bran fractions was varied by various milling techniques. All fractions were added to white flour and water addition was adjusted to obtain dough with a constant consistency. 相似文献