Will isomalto-oligosaccharides, a well-established functional food in Asia, break through the European and American market? The status of knowledge on these prebiotics

in Critical Reviews in Food Science & Nutrition (2011)

This critical review article present the current state of knowledge on isomaltooligosaccharides, some well known functional oligosaccharides in Asia, to evaluate their potential as emergent prebiotics in ... [more ▼]

This critical review article present the current state of knowledge on isomaltooligosaccharides, some well known functional oligosaccharides in Asia, to evaluate their potential as emergent prebiotics in the American and European functional food market. It includes first a unique inventory of the different families of compounds which have been considered as IMO and their specific structure. A description of the different production methods including the involved enzymes and their specific activities, the substrates and the types of IMO produced. Considering the structural complexity of IMO products, specific characterization methods are described as well as purification methods which enable the riddance of digestible oligosaccharides. Finally an extensive review of their techno-functional and nutritional properties enables to place IMO inside the growing prebiotic market. This review is of a particular interest considering that IMO commercialization in America and Europe is a topical subject due to the recent submission, by Bioneutra INC. (Canada), of a novel food file to the UK Food Standards Agency as well as several patents for IMO production. [less ▲]

Dietary fibre and fibre-rich by-products of food processing characterisation, technological functionality and commercial applications: a review

in Food Chemistry (2011), 124

Synthèse des connaissances sur la déshydratation osmotique

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2011), 15(1), 129-142

Parmi les procédés de conservation des produits végétaux, la déshydratation osmotique présente un intérêt économique et nutritionnel certain. Cette technique, économe en énergie, est susceptible de ... [more ▼]

Parmi les procédés de conservation des produits végétaux, la déshydratation osmotique présente un intérêt économique et nutritionnel certain. Cette technique, économe en énergie, est susceptible de prolonger la période de disponibilité des produits alimentaires et leur confère des propriétés sensorielles nouvelles et appréciées. Elle permet ainsi aux acteurs de la filière agro-alimentaire d’écouler leurs productions à de meilleurs prix et aux consommateurs d’en disposer tout au long de l’année. Cette technique est un outil facile à mettre en place, surtout dans les pays en voie de développement, en raison de son faible cout. Le présent article a pour objectif de présenter une synthèse de la littérature concernant la technique de déshydratation osmotique afin d’en rappeler les bases théoriques et pratiques, mais aussi d’en préciser les nouvelles tendances et voies de recherches récentes. [less ▲]

Effect of ageing on different egg yolk fractions on surface properties at the air–water interface

in International Journal of Food Science & Technology (2011), 46

The aim of this study was to evaluate the impact of egg ageing on the surface properties of whole and fractionated yolk at the air–water interface. Eggs were stored at 4 Cfor 24 h, 1 week and 3 weeks ... [more ▼]

The aim of this study was to evaluate the impact of egg ageing on the surface properties of whole and fractionated yolk at the air–water interface. Eggs were stored at 4 Cfor 24 h, 1 week and 3 weeks after laying.A laboratory scale fractionation process was then applied at each ageing time. Egg yolk was separated into two fractions, plasma composed of low-density lipoproteins (LDLs) and livetins, and granules formed by highdensity lipoproteins (HDLs), phosvitins and LDLg (g = granule). Moreover, recombined plasma and granules fractions were investigated to highlight a potential synergic effect on surface properties. Results have shown the main contribution of LDLs on surface properties of yolk and an improvement of granules surface properties when they are disrupted. Moreover, ageing affected surface properties differently depending on the considered fractions. Broken LDLsand disrupted granules could explain this observed behaviour. Recombined fractions showed different compression isotherms at the air–water interface than whole yolk. [less ▲]

Synthesis and Surface-Active Properties of Uronic Amide Derivatives, Surfactants from Renewable Organic Raw Materials

in Journal of Surfactants and Detergents (2011), 14(1), 51-63

Short chemical syntheses were developed to produce a new set of surfactants from uronic acids derived from widely available raw material. Three different strategies were used to synthesise uronic amide ... [more ▼]

Short chemical syntheses were developed to produce a new set of surfactants from uronic acids derived from widely available raw material. Three different strategies were used to synthesise uronic amide derivatives, the structures of which were totally characterized by spectrometric methods (IR, MS, 1H-RMN and 13C-RMN). The best one, using an acid chloride as synthetic intermediate, furnished the expected amides as a mixture of anomers in 46 to 58 % global yield. Surface-active properties (CMC, g cmc, Tmax, Amin) of homologous series of uronic acid N-alkylamides from C8 to C18 were also assessed. In general, these sugar-based surfactants exhibited good surface-activities, and appeared as valuable non ionic surfactants compared to Triton X-100, the most well-known non ionic surfactant. Increasing the alkyl chain length influenced the CMC values for both glucuronic and galacturonic N-alkylamide derivatives. The galacturonic N-alkylamides decreased g cmc at slower values than their counterpart's glucuronic N-alkylamides. [less ▲]

Front-face fluorescence spectroscopy: a tool for differentiating sheep milks originating from different genotypes and feeding systems

in Precision Livestock Farming (2011)

La conservation des aliments réfrigérés

Conference given outside the academic context (2010)

Enzymatic synthesis of novel carbohydrate surfactants for water/supercritical CO2 emulsions

Poster (2010, October 14)

Towards the synthesis of mannose derivatives of natural phenolic compounds

Poster (2010, October 14)

The aim of this project is to graft a sugar moiety onto polyfunctional natural phenolic compounds. This should enhance their water solubility. The choice of an adequate sugar such as mannose could provide ... [more ▼]

The aim of this project is to graft a sugar moiety onto polyfunctional natural phenolic compounds. This should enhance their water solubility. The choice of an adequate sugar such as mannose could provide cellular recognition. The synthesis route was first tested on cinnamyl alcohol which is structurally close to the base pattern of natural phenolic compounds. Two compounds are tested to catalyse the glycosilation between cinnamyl alcohol and D-mannose. The first one is an enzyme, the -glucosidase from almond, and the second one is a mineral acid catalyst immobilized on silica. Results show that -glucosidase is able to synthetize cinnamyl mannoside from mannose and cinnamyl alcohol. Furthermore, enzyme-catalyzed route lead to only one product and is so more specific than the chemical route where several products are observed. The obtaining of one product with a unique structure is interesting for the fundamental study of structure-function relationships (Interaction of the product with model membranes by Isothermal Titration Calorymetry and with the Langmuir Trough technique). In a future work, the reaction will be tested with more complex molecules (for example coniferyl alcohol). [less ▲]

A method for the production of prebiotic preparations containing isomaltooligosaccharides and gluconic acid.

Poster (2010, October 14)

Isomaltooligosaccharides (IMOs) are non-digestible oligosaccharides, considered as prebiotics and therefore aim to selectively feed probiotics indigenous to the human colon. IMOs consists of glucose ... [more ▼]

Isomaltooligosaccharides (IMOs) are non-digestible oligosaccharides, considered as prebiotics and therefore aim to selectively feed probiotics indigenous to the human colon. IMOs consists of glucose monomers linked by at least one α-1-6, or in a lower proportion α -1-3 (nigerose family) or α -1-2 (kojibiose family) glucosidic linkages. In our case they are produced from either corn, tapioca, or rice hydrolyzed starch. The enzymatic reaction is achieved using an Aspergillus niger transglucosidase (EC 2.4.1.24). It results in a very complex mixture with molecules characterized at the same time by their DP value (from 2 to ~15), linkages types (α-1-2, 3 or 6) and the proportion and position of each type of linkage (only α -1-6 or combined types). However, the reaction only permits to reach yields between 50-75 % in IMOs. Impurities are composed of residual maltooligosaccharides (glucose with exclusively α -1-4 linkages) from the starting vegetal material and glucose released during the transglucosylation step. These digestible saccharides are deleterious for the prebiotic preparation. Therefore, these compounds must be eliminated from the medium or converted in prebiotic species. Residual maltooligosaccharides are thus specifically hydrolyzed by a thermostable α-glucosidase (EC. 3.2.1.20) in order to produce glucose as the only unwanted specie. This glucose can then be converted to gluconic acid and/or its salts using a glucose-oxidase (EC. 1.1.3.4) in combination with a catalase. Gluconic acid (C6H12O7) is a saccharide derivative which has been recognized as a prebiotic compound. It is also known for its purgative action and proved to be effective for lipid peroxidation prevention. A first option can then be chosen, leaving gluconic acid in the product in order to obtain an original prebiotic product enjoying new prebiotic potential properties due to the combination of both types of prebiotic compounds (IMO and gluconic acid). The second option is to eliminate the gluconic acid from the prebiotic mixture. This separation doesn’t present the same difficulties than for glucose as gluconic acid is charged and can therefore be separated on anion-exchange resins (Dowex AcO-). This overall process, fulfilling the principles of green chemistry and being applicable to produce organic prebiotic, is an elegant solution, from an economical, an environmental, a nutri-functional and a techno-functional point of view. Indeed, it can lead to original prebiotic preparations, with yields close to 100%, by avoiding product loss, as the digestible saccharides portion is converted to gluconic acid. Furthermore, the presence of gluconic acid can provide many functional properties to the prebiotic preparations for their incorporation in food products. [less ▲]