Preparation of sunflower isolates at a pilot-plant scale

At a pilot-plant scale, various patented processes for preparation of sunflower isolates were examined. The objectives of these processes are to improve the quality of the isolates (particularly their protein content), to reduce their content of glucidic substances (which obstruct spinning) and to improve their color. A correlation exists between these parameters and isolate yields. Our results, obtained with industrial meals, should be largely improved with respect to yield and color with meals obtained from dehulled kernels which have not been subjected to as much heat-treatment as the industrial meals.     

Thermal decomposition,chemical composition,in vitro digestibility and gas production and in situ degradability of oilseed residues from the biofuel industry

Thermal analysis could rapidly and easily predict nutritional value of ruminant feeds. The hypothesis is that crambe meal (CM) has a quality similar to that of soybean meal (SM), and the objective of this study was to determine the nutritional characteristics of CM and compare them to those of SM. CM had greater concentrations of phytic acid (26.3 vs. 16.0 g/kg) and phenol compounds (615 vs. 393 mg gallic acid (GAE)/kg) than SM. In vitro dry matter (DM) digestibility was lower for CM than SM (752 vs. 975 g/kg DM). Cumulative in vitro gas production at 48 h of incubation (14.1 vs. 19.4 mL/100 mg substrate DM), and energy release (4.5 vs. 5.7 kJ/g substrate DM) were lower for CM than SM. CM had a higher concentration of low digestible fiber, hence degradability of DM was lower and the proportion of indigestible fraction was greater for CM than SM. High concentrations of indigestible compounds were likely responsible for lower gas production of CM compared to SM. These results suggest CM quality is lower than that of SM and that thermal analysis is a useful tool to precisely determine the nutritive value of oilseed residues.     

Characterisation of the environmental impact of a turbot (Scophthalmus maximus) re-circulating production system using Life Cycle Assessment

The environmental impacts of a water re-circulating system for fish farming were studied through the case study of an inland turbot farm located in Brittany (France). Life Cycle Assessment methodology was used to evaluate the potential environmental impact through the following indicators: Eutrophication Potential, Acidification Potential, Global Warming Potential, Net Primary Production Use and Non Renewable Energy Use. Two methods were used to assess the farm's nitrogen, phosphorus and solids emissions: nutrient measurement accounting and nutrient balance modelling. The two methods gave similar results for solids and phosphorus emissions, while for nitrogen the measurement-based approach resulted in half the emissions predicted by the model. The uncertainty regarding the potential gaseous nitrogen emissions led us to assess impacts according to three scenarios, differing with respect to emissions of N₂, N₂O and NH₃. This approach illustrates that the uncertainty concerning nitrogenous emissions to the atmosphere leads to uncertainty with respect to the production system's Eutrophication Potential and its Global Warming Potential. The comparison of our results with similar results for large rainbow trout production in a flow-through system points out the impacts associated with the high level of energy consumption in the studied re-circulating system (i.e. Non Renewable Energy Use, Global Warming potential, Acidification Potential). The nitrogenous gas emissions of re-circulating systems require further studies, in order to precisely identify the substances involved and the technological solutions allowing reduced impacts.     

Assessing habitat quality for butterflies on intensively managed arable farmland

The conservation and management of biodiversity requires accurate, repeatable and cost-effective monitoring techniques. In this study, a simple and rapid methodology was employed to measure the quality of different habitats for butterfly species on 10 arable farms in lowland Britain. This habitat monitoring was seven times more rapid than the traditional species-based butterfly monitoring. Data on butterfly abundance were combined with the information gathered on habitat quality at five of the farms using stepwise regression. These models had a consistently high degree of explanatory power for the summary variables of total butterfly abundance and species richness, and the functional groupings of mobile and immobile species. There was good agreement between observed and predicted estimates of species richness and abundance when the models were validated on a further five independent sites. Models to predict the abundance of 11 common butterfly species were also produced. These varied considerably in their predictive power and validity between species. The results clearly demonstrated the beneficial effects of targeted habitat creation for butterflies which is promoted under the Agri-environment Schemes, especially the recently introduced pollen and nectar seed mixtures (WM2) available under the Countryside Stewardship Scheme. The models confirmed the importance of shelter, floristically diverse field margins and the availability of nectar resources from legume species in explaining the abundance of immobile butterfly species in arable landscapes. These sources of nectar and the presence of larval host plants in the crucifer family were important factors in explaining the abundance of mobile species. The results are discussed in terms of the potential of this approach for: (i) assessing habitat quality for butterflies in intensively managed landscapes; (ii) enhancing the value of butterfly monitoring schemes in explaining changes in butterfly abundance at the site and national scale; and (iii) informing habitat management and restoration guidelines for butterfly conservation on arable farmland.     

Search for hydrophilic marine fungal metabolites: a rational approach for their production and extraction in a bioactivity screening context

In the search for bioactive natural products, our lab screens hydrophobic extracts from marine fungal strains. While hydrophilic active substances were recently identified from marine macro-organisms, there was a lack of reported metabolites in the marine fungi area. As such, we decided to develop a general procedure for screening of hydrophobic metabolites. The aim of this study was to compare different processes of fermentation and extraction, using six representative marine fungal strains, in order to define the optimized method for production. The parameters studied were (a) which polar solvent to select, (b) which fermentation method to choose between solid and liquid cultures, (c) which raw material, the mycelium or its medium, to extract and (d) which extraction process to apply. The biochemical analysis and biological evaluations of obtained extracts led to the conclusion that the culture of marine fungi by agar surface fermentation followed by the separate extraction of the mycelium and its medium by a cryo-crushing and an enzymatic digestion with agarase, respectively, was the best procedure when screening for hydrophilic bioactive metabolites. During this development, several bioactivities were detected, confirming the potential of hydrophilic crude extracts in the search for bioactive natural products.     

Influence of High‐Temperature Drying on Structural and Textural Properties of Durum Wheat Pasta

Starch and protein are the main polymeric ingredients of pasta and they determine the structural and textural properties of cooked pasta. The present investigation sought better understanding of the impact of high‐temperature (HT) drying on the starch and the protein fraction, and their role in structure and texture of pasta. Durum wheat spaghetti was prepared in a pilot‐plant installation. The drying conditions were selected for the HT phase at 80 or 100°C applied at high, intermediate, or low product moisture content. Spaghetti dried at 55°C served as a reference sample. The color of dry pasta was measured and the changes in the starch and protein fractions were determined by protein solubility, light microscopy, confocal scanning laser microscopy (CSLM), cooking tests, and texture measurements. HT drying at 100°C and low product moisture promoted browning of pasta. At the molecular level, HT drying promoted protein denaturation. At the microscopic level, HT drying contributed to a better preservation of the protein network and reduced swelling of starch and disintegration of granules. At the macroscopic level, HT drying enhanced the firmness of cooked pasta and reduced surface stickiness. In general, the changes were more pronounced by increasing the drying temperature from 80 to 100°C and by shifting the HT phase from an early to a late stage of the drying process. The drying conditions are determinant for the phase morphology of protein and starch in cooked pasta which, in turn, govern the textural properties of pasta.