Valorisation of agro‐industrial by‐products,effluents and waste: concept,opportunities and the case of olive mill wastewaters

Valorisation is a relatively new concept in the field of industrial residues management promoting the principle of sustainable development. One of the valorisation objectives regarding food processing by‐products, waste and effluents is the recovery of fine chemicals and the production of precious metabolites via chemical and biotechnological processes. This paper identifies and discusses certain directions that seem to advance valorisation, as well as existing limitations that need to be overcome in the food processing sector. A valorisation strategy is exemplified for the wastewaters arising from the olive oil extraction process; the recovery of antioxidants by chemical methods and the fermentative production of enzymes of commercial interest have been reviewed. Copyright © 2009 Society of Chemical Industry     

Influence of salinity on lead and cadmium accumulation by the salt cedar (Tamarix smyrnensis Bunge)

BACKGROUND: The removal of heavy metals from polluted soils through the use of suitable plants has attracted much interest over recent decades. In this study Tamarix smyrnensis Bunge has been investigated for the characterization of its metal tolerance and ability to accumulate Pb and Cd, in order to evaluate its effectiveness as a cleanup tool for phytoextraction applications. For this purpose, two hydroponic experiments were performed, one with lead at concentration 100 ppm and a second with cadmium at concentration 5 ppm and at three different salt concentrations (0, 100, 200 mmol L^?1 NaCl). RESULTS: The experimental results showed that Pb and Cd accumulation in shoots ranged from 150–270 ppm and 7.5–42 ppm, respectively, and salinity was found to increase metal accumulation in shoots. However, the presence of high metal and salt concentrations affected negatively the health and finally the survival of the plants. CONCLUSION: T. smyrnensis is neither a Pb nor a Cd hyperaccumulator; however, metal accumulation levels in shoots considered together with its high biomass production suggest that it could be used for phytoextraction applications. Furthermore, salinity has a positive influence on Pb and Cd accumulation in harvestable parts of the plant when it remains in low concentrations. Copyright © 2009 Society of Chemical Industry     

Active learning for object classification: from exploration to exploitation

Classifying large datasets without any a-priori information poses a problem in numerous tasks. Especially in industrial environments, we often encounter diverse measurement devices and sensors that produce huge amounts of data, but we still rely on a human expert to help give the data a meaningful interpretation. As the amount of data that must be manually classified plays a critical role, we need to reduce the number of learning episodes involving human interactions as much as possible. In addition for real world applications it is fundamental to converge in a stable manner to a solution that is close to the optimal solution. We present a new self-controlled exploration/exploitation strategy to select data points to be labeled by a domain expert where the potential of each data point is computed based on a combination of its representativeness and the uncertainty of the classifier. A new Prototype Based Active Learning (PBAC) algorithm for classification is introduced. We compare the results to other active learning approaches on several benchmark datasets.     

Submarine hull integrity under blast loading

The paper deals with numerical methodologies to model and study the structural resistance of submarine hull against explosions, where fluid and solid phenomena interact. Explosion Crack Starter Tests (ECST), which are a standard procedure to study submarine materials and weldments with respect to blast loading, are modelled using an explicit FE code that solves Fluid/Structure (F/S) interactions within the same computation. The proposed numerical methods aim at computing the structural response of a target subjected to sequential explosions. Numerical results are compared to the corresponding explosion tests (ECST) performed by DGA (French Ministry of Defence).     

Effect of controlled differential sieving processing on micronutrient contents and in vivo antioxidant activities of Hibiscus sabdariffa L. calyxes powder

Food Science and Biotechnology - Sun-dried calyxes of Hibiscus sabdariffa were finely grinded and fractionated by controlled differential sieving processing (CDSp) into four granulometric classes....     

Antimicrobial Effects of Nisin,Essential Oil,and γ‐Irradiation Treatments against High Load of Salmonella typhimurium on Mini‐carrots

This study aimed at using essential oil (EO) alone or combined EO with nisin and γ‐irradiation to control Salmonella Typhimurium during the refrigerated storage of mini‐carrots. Peeled mini‐carrots were inoculated with S. Typhimurium at a final concentration of approximately 7 log CFU/g. Inoculated samples were coated by 5 different coating solutions: (i) nisin solution at final concentration of 10³ IU/mL; (ii) mountain savory EO solution at 0.35%; (iii) carvacrol solution at 0.35%; (iv) mountain savory EO at 0.35% plus nisin solution of 10³ IU/mL; or (v) carvacrol at 0.35% plus nisin solution of 10³ IU/mL. Coated mini‐carrots were then irradiated at 0.5 or 1.0 kGy and compared to an unirradiated control sample. Samples were kept at 4 °C and microbial analyses were conducted at days 1, 3, 6, and 9. The results showed that mini‐carrots coated by carvacrol plus nisin solution or mountain savory EO plus nisin solution in combination with irradiation at 1.0 kGy completely eliminated S. Typhimurium to under the detection limit during the storage. Thus, the combined treatments using carvacrol plus nisin or mountain savory EO plus nisin coating solution and irradiation at 1.0 kGy could be used as an effective method for controlling S. Typhimurium in mini‐carrots.     

Evidence of 4-ethylcatechol as one of the main phenolic off-flavour markers in French ciders

A new HPLC method using a diode array detector was developed and validated to quantify 4-ethylphenol, 4-vinylphenol, 4-ethylguaiacol, 4-vinylguaiacol and 4-ethylcatechol in cider. The procedure was linear up to 150 mg/l for each of the five volatile phenols, precise (RSD < 2.9%) and sensitive, with limits of detection between 0.03 and 0.10 mg/l; moreover, it did not require any sample preparation. This method was applied to 11 phenolic off-flavour defective ciders. In these ciders, the main volatile phenol corresponded to 4-ethylcatechol. Moreover, the observed concentrations (maximum of 164 mg/l) indicated, for the first time, that this compound is an important phenolic off -flavour marker in cider. Then, volatile phenols concentrations were determined for 47 French commercial ciders and showed mean quantities of 3.2 (4-EC), 0.8 (4-EP), 0.1 (4-EG), 0.2 (4-VP) and 0.3 mg/l (4-VG). The majority of the tested commercial ciders presented low volatile phenol levels.     

Removal of organochlorines from vegetable oils and its benefits in preventing formation of monochloropropanediol diesters

This paper reports the first results on depleting certain organochlorines from vegetable oils without the use of any solvent in order to mitigate monochloropropanediol diesters (MCDPE). The concept is based on separating the organochlorines from the bulk oil by using trapping agents (e.g. monoacylglycerols) that can be easily separated from the oil. The process starts by mixing and homogenizing crude vegetable oils with the trapping agent and subsequently separating the trapping agent from the oil bulk via crystallization. The proof-of-concept of the approach is demonstrated on a spiked sunflower model system, solvent extracted crude sunflower oil, industrially produced crude soybean and corn oils. The depletion of organochlorines in the crude oils and its beneficial effect on the MCPDE content in the heat treated samples is measured by LC-MS. The depletion efficacy of the monitored organochlorines was estimated to be in the 60–95 % range. Both the melting point and polarity of the trapping agents affected the depletion efficacy of the organochlorines. Trapping agents with higher melting point and polarity, such as monostearin were more effective in comparison to high melting point but less polar agents such as palm stearin or agents rich in polar but low melting point monolinolein/monoolein. The effect of organochlorine depletion on the subsequent MPCDE levels in heat treated oil was in the range of 60–90 % reduction depending on the type of the studied oil.     

The synthesis, physicochemical properties and anodic polymerization of a novel ladder pentaphenylene

The synthesis, crystal structure, electrochemical and optical properties of a novel blue emitting ladder pentaphenylene are reported and compared with those of its 3π−2 spiro parent, in order to study the effect of the spiro-linked fluorene rings. Anodic oxidation of the novel compound results via electropolymerization, in the formation of an electroactive material that displays interesting electrochemical and optical properties.