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Glass transition phenomena applied to powdered amorphous food carbohydrates. During these last fifteen years, some food technologists and scientists have become aware of the importance of the glass transition, a thermal property of glassy or amorphous material, in food preparation processes. Recent studies have successfully correlated this fundamental notion to technofunctional changes within the powder. The aim of this paper is to present in a non exhaustive manner the relationship between glass transition characteristics and applications in food technology (caking, alterations, etc.).

Five hydrodynamic systems are presented in this short review: the parallel plate flow cell, the impinging jet, the radial flow cell, the rotating disk and fluid dynamic gauging. These systems are of particular relevance to study surface fouling, surface cleaning or adhesion onto solid surfaces in laboratory environment. The key features of their hydrodynamics are given as well as their practical advantages and drawbacks. Examples of applications fields are also listed.

Sugar esters : ways of synthesis and potential applications [a review]. Sugar esters are nonionic surfactants and exhibit relevant properties as structural diversity and environmental and health safety. Their potential applications extend from human food to drugs formulation and biochemical studies. Some sugar esters also exhibit interesting biological activities. A lot of papers have been submitted during the last ten years. Those articles describe the various ways of synthesis of those compounds at the laboratory scale. During the last ten years, the most studied method was the biotechnological way using enzyme as a catalyser.

Composite breads based on sorghum-wheat flour blends and textural analysis. Breadmaking properties of flour blends containing various levels of sorghum flour with wheat flour were investigated. Good quality bread (loaf volume, crumb structure, external appearance) comparable to bread entirely made from wheat flour could be produced with a level of incorporation of sorghum flour up to 30/. Beyond this level, the loaf volume decreases and the internal characteristics of crumb are deteriorated. The staling of bread made with composite flour is also influenced by the level of substitution of sorghum flour: the more important this level, the higher the rate of crumb firming. Addition of 0.5/ emulsiflers, DATEM and SSL, to the sorghum flour blends improves the crumb characteristics and consequently delays the bread firmness.

Structures and phenomena occurring during the heat treatment of cornstarch. The structure of cornstarch and the modifications induced during the heat treatments are presented in this review. Current knowledge indicate that the starch granules are semi-crystalline entities composed mainly by amylose and amylopectin, undergoing deep reorganizations during the heat treatments. Gelatinization, glass transitions, relaxation phenomena, retrogradation and the formation of amylose-lipids complexes are the major phenomena involved in these reorganisations, and are the basis of changes of the techno-functional properties of cornstarch-based products during their heat treatment. La rhizosphère est le volume du sol situé au voisinage immédiat des racines des plantes et qui se caractérise par la présence d'exsudats racinaires (rhizodépôts). Ces exsudats sont utilisés par la microflore endémique en tant que signaux chimiques en plus d'être un substrat nutritif disponible pour la croissance et le développement de ces microorganismes dans la rhizosphère. Certaines de ces bactéries du sol, appelées PGPRs (Plant Growth Promoting Rhizobacteria), sont capables de coloniser les racines ou bien encore la rhizosphère, mais à la différence des autres bactéries rhizosphériques elles ont, en retour, un effet bénéfique sur la plante. Cet effet bénéfique peut être direct, ou indirect. La promotion directe de la croissance est le résultat du pouvoir d'acquisition des nutriments ou de la stimulation des hormones de la plante. D'autres mécanismes indirects, mais le plus souvent liés à la croissance des plantes, sont impliqués dans la réduction/suppression des pathogènes des plantes. Cet article décrit les différents mécanismes mis en jeu par les PGPRs dans leur environnement naturel pour influencer favorablement la croissance et la santé des plantes.

Buttermilk, the by-product from butter manufacture, is low cost and available in large quantities but has been considered for many years as invaluable. However, over the last two decades it has gained considerable attention due to its specific composition in proteins and polar lipids from the milk fat globule membrane (MFGM). The aim of this review is to take stock of current buttermilk knowledge. Firstly, the milk fat globule membrane composition and structure are described. Secondly, buttermilk and its associated products are defined according to the milk fat making process. Structure and mean composition of these products are summarized from recent dairy research data and related to technological properties, especially the emulsifying properties provided by MFGM components. Finally, new applications are presented, leading to promising valorizations of buttermilk and its derivate products.

Enzymic hydrolysis of residual fat with a sn 1,3 specific lipase improves the emulsifying and foaming capacities of sweet whey and whey protein concentrate (WPC). Lipase-treated sweet whey and WPC show low equilibrium surface tension, high compressibility modulus of films at the water surface and a high adsorption rate to the air-water interface. Hydrolysis converts the triglycerides into strong surface-active mono- and diglycerides. This improves the capability and steadiness of the foam and the emulsion. These emulsions and foams are more shelf-stable than those of the native products.

The gelling properties of whey protein concentrate after residual fat hydrolysis are described.

In order to determine the importance of cis or trans unsaturations from a technological point of view, the study of the structural and thermal properties of monoacid triglycerides: tristearin (SSS), triolein (OOO) and trielaidin (EEE) has been undertaken. X-ray powder diffraction and differential scanning calorimetry are useful tools to elucidate the physicochemical properties of such compounds. In this work polymorphism, kinetics of polymorphism and intersolubility have been investigated. From a structural point of view, we have shown that, according to the polymorphic form, the conformational properties of EEE are similar to those of the corresponding saturated molecule SSS or to those of the cis unsaturated analogue OOO. The study of the intersolubility behavior of these three compounds has shown a different affinity of the cis and trans unsaturated molecules vs the completely saturated one. By the same method, we have observed that trans unsaturated hydrocarbon chains cocrystallize with both cis-unsaturated (OOO) and totally saturated hydrocarbon chains (SSS); the trans double bond of EEE can adapt to the two kinds of lattices. The study of the kinetics of polymorphism has shown that 5% of OOO or EEE accelerate the β′→β transition of SSS, while the reason for the two phenomena is quite different. The adaptation of EEE to cis-unsaturated and to saturated hydrocarbon chains shown in the structural and intersolubility behavior analyses also appears in the kinetic study, after adjunction of 5% of OOO into EEE. All the results confirm that, from structural and thermal points of view, EEE has an intermediate behavior between SSS and OOO. [ABSTRACT FROM AUTHOR]