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The purification and fractionation of phenolic compounds from crude plant extracts using a food-grade acrylic adsorbent were studied at pilot-plant scale. A diluted apple juice concentrate served as a model phenolic solution for column adsorption and desorption trials. Phenolic concentrations were evaluated photometrically using the Folin-Ciocalteu assay and by HPLC-DAD. Recovery rates were significantly affected by increasing phenolic concentrations of the feed solutions applied to the column. In contrast, the flow rate during column loading hardly influenced adsorption efficiency, whereas the temperature and pH value were shown to be crucial parameters determining both total phenolic recovery rates and the adsorption behavior of individual polyphenols. As expected, the eluent composition had the greatest impact on the desorption characteristics of both total and individual phenolic compounds. HPLC analyses revealed significantly different elution profiles of individual polyphenols depending on lipophilicity. This technique allows fractionation of crude plant phenolic extracts, thus providing the opportunity to design the functional properties of the resulting phenolic fractions selectively, and the present study delivers valuable information with regard to the adjustment of individual process parameters.

Aimralian crude oil.s. which generally contain little asplmltcne.s. nevcrihcless give rise to fouling in refinery pre heat trains. In this research, the fouling of a 'ieries of such crude oils and their blends is being assessed. The present work focuses on thermal folding resulting from heating Gippsland crude oil at moderate temperanires. The oil is maintained under nitrogen at a pressure of379kPa and re-circulated at bulk temperatures of 80-120''C through an electrically heated annular probe at velocities in the range 0.2.5-0.65 m/s with surface temperature.''from ISO-260'C. Experiments are run for periods up to ninety hours ar ctmstant heat flin\ Fouling Is detected hy the increase of wall temperature of the probe. The oil is characterized by its filterable solids content, density, and vi.scosity both before and after the fouling run. The trends in fouling ralex are compared to predictions ofthe threshold-fouling model proposed by Ebert and Panchal [6]. Data on deposit composition are presented, and the fouling mechanism is discu.ssed.

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With the increased consumer interest in fibre-enriched functional foods, industrial-scale methods for functional fibre production are demanded. The development of a food-grade fibre preparation method at lab scale that is feasible for industrial scale-up is a pre-requisite. This paper describes two lab-scale fibre preparation methods that have potential to be scaled up to industrial setting for the production of fruit fibres containing desired bioactives and functionality. The two methods, one aqueous and the other ethanolic, were used to isolate fibres from Granny Smith apples (Malus domestica Borkh cv. 'Granny Smith'). In the aqueous method, ground apple tissues were suspended in HEPES buffer (20 mM, pH 6.5), and then mechanically ruptured using an Ultra-Turrax and ring grinder. Between steps, the cell-wall materials were washed with the HEPES buffer. In the ethanolic method, ground apple tissues were stirred in 72% ethanol at 4°C, filtered, resuspended in 72% ethanol and then washed. Microscopic examination and chemical analysis were performed on the resultant fibres. The aqueous method produced natural and uniform dietary fibres in the form of plant cell walls containing 0.282 g uronic acid per g dried fibre. By comparisons, the ethanolic method produced crude fibres containing only 0.182 g uronic acid per g dried fibre, the lower uronic acid content indicating the presence of impurities. Thus, the aqueous method appeared to be advantageous in terms of the retained pectic polysaccharide content and cost-effectness for industrial scale-up. Further characterisation using Folin-Ciocalteu assay and high performance liquid chromatography indicates that the fibres obtained by the aqueous method contained significant amounts of phenolic compounds (2.6 mg catechin equivalent per g dried fibre). These results suggest that fibres obtained by the aqueous method may be more suitable for functional food applications where fibres with high pectic polysaccharide and beneficial phenolic antioxidants are preferred.