Roux S.,UMR 95 QualiSud |
Petit M.,UMR 0868 SELMET |
Baeza E.,French National Institute for Agricultural Research |
Bastianelli D.,CIRAD - Agricultural Research for Development |
And 2 more authors.
European Journal of Lipid Science and Technology | Year: 2014
Lipid oxidation is a standard parameter in the evaluation of meat quality. It is most often used when the composition of the meat is modified, either by changing the animal's diet or by adding food supplements during post-slaughter meat processing. Malonaldehyde (MA) is commonly accepted as the main lipid oxidation product in meat. In this study, changes in MA contents in chicken meat enriched with n3-PUFA during cooking were analysed. Small samples (1.5g) of ground chicken thighs were placed in plastic bags, wrapped in thin film, and immersed in a water bath at different temperatures (50, 70 and 100°C) for cooking times ranging from 0 to 30min. MA content was measured by liquid chromatography. MA content first increased rapidly and then decreased. The kinetics were fitted to a model using sequential first-order reactions including appearance and disappearance rate constants. The temperature influenced the rate constants according to Arrhenius' law, with the highest activation energy for the appearance rate constant. An increase in the vitamin E content of the meat reduced the appearance rate but not the disappearance rate constant. Practical applications: This study investigates the possibility of modelling the MA content in n3-PUFA enriched chicken meat during cooking in order to predict the lipid oxidation state of the meat consumers would eat. By understanding the mechanisms of MA appearance and disappearance reactions according to the level of antioxidant present in the meat, this study enables to monitor the lipid oxidation extent. The utility of vitamin E as an antioxidant in n3-PUFA enriched chicken meat is demonstrated. This study also enlightens the behaviour of the MA, the compound most widely used in literature to characterize the lipid oxidation extent, which is a transition product and must be used with care. In fact, it is clearly shown that a single value of MA content cannot express an oxidation state due to cooking without prior focus on the complete kinetics to determine the appearance and disappearance phases of the MA. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Prades A.,UMR 95 Qualisud |
Dornier M.,UMR 95 Qualisud |
Dornier M.,Montpellier SupAgro |
Diop N.,Institute Technology Aliment Ita |
Pain J.-P.,Montpellier University
Fruits | Year: 2012
The product. Coconut water (Cocos nucifera L.) is an ancien t tropical beverage whose popularity on the international market has been continuously increasing in recent years. Uses. Besides its various traditional uses, this refreshing liqu id extracted from the coconut fruit has recently been described as a "sport beverage" and has drawn the attention of manufacturers as a natural functional drink. Composition. Coconut water has a low matter content (2% to 5% wet basis), mainly comprising sugars and minerals. Quality criteria, such as the water per nut ratio, Total Soluble Solids (TSS), total sugar per nut, and [reducing sugars/total sugars] ratio, are good indicators for estimating the suitability of coconut cultivars for the production of coconut water. Regarding these criteria, dwarf varieties are the most suitable cultivars to obtain a tasty product. Properties. The quality of coconut water can not only be attributed to sugars and minerals because it also has a typical flavour and some original properties. Although many authors have cited medicinal uses or growth-promoting activities, only a few publications have clearly identified the components responsible for these properties. Discussion. Results of former and recent investigations are discussed. Finally, suggestions are made for further research to increase our knowledge of this original tropical juice. © 2012 Cirad/EDP Sciences All rights reserved.
Achir N.,UMR 95 QualiSud |
Penicaud C.,UMR 95 QualiSud |
Avallone S.,UMR 204 NutriPass |
Bohuon P.,UMR 95 QualiSud
JAOCS, Journal of the American Oil Chemists' Society | Year: 2011
The aim of this study was to gain further insight into β-carotene thermal degradation in oils. Multiresponse modeling was applied to experimental highperformance liquid chromatography-diode array detection (HPLC-DAD) data (trans-, 13-cis-, and 9-cis-β-carotene concentrations) during the heat treatments (120-180 °C) of two β-carotene-enriched oils, i.e., palm olein and copra. The test of different reaction schemes showed that β-carotene isomerization reactions were dominant and reversible. The resulting cis isomers and trans-β-carotene simultaneously underwent oxidation and cleavage reactions at the same rate constant. From the kinetic analysis, it appeared that - contrary to oxidation and cleavage reactions - isomerization rate constants did not follow the Arrhenius law. However, the isomerization equilibrium constant increased with temperature, favoring isomer production, particularly 9-cis-β-carotene. Its production was shown to be concomitant with oxidation and cleavage reactions, indicating that 9-cis-β-carotene could be a good degradation indicator during oil storage or processing. © AOCS 2011.