Performance of lipid‐based moisture barriers in food products with intermediate water activity

Nine lipid‐based barrier films (three chocolates, acetomonopalmitine, white beeswax, and four commercial blends: two acetoglycerides/beeswax blends, two hydrogenated and fractionated vegetable oils) were characterised using classical water‐related and physical properties of edible barriers, such as water vapour permeability, moisture adsorption isotherm, moisture effective diffusivity, surface hydrophobicity, firmness and solid fat content (20 °C). Classifications based on these properties were established and compared to the barrier efficiency under real conditions of use, i.e. in a model food product (cereal‐based component – intermediary a_w gel). Moisture migrations were performed using self‐supported barriers (300 µm) and fitted with a predictive model based on Fick's Second Law. White beeswax and acetoglycerides enabled the best extensions of the dry‐component shelf life from 2 h to between 100 and 330 h. Moisture effective diffusivity and calculated water vapour permeability combined to a mechanical property evaluation of the barrier were more discriminating to assess the barrier efficiency in the model food than the moisture sorption and experimental water vapour permeability. The importance of combining both water‐related and physical characteristics of the barrier and the advantages of an integrated approach through the simulation of the material behaviour under its real conditions of use with the model are highlighted.     

Modification of liquid/solid interface shape in directionally solidifying Al–Cu alloys by a transverse magnetic field

Al-0.85wt%Cu and Al-2.5wt%Cu alloys were directionally solidified under different transverse magnetic field (TMF) intensities to investigate the influence of TMF on the liquid/solid interface shape with respect to the various length scales appearing (planar, cellular, and dendritic interfaces). Results show that planar and cellular interfaces tilt to one side and then level off with increasing TMF although the dendritic interface appears not to behave in this manner. In situ synchrotron X-ray imaging was applied during directional solidification of the Al-4wt%Cu alloy under a 0.08T TMF, revealing leveling of the initially sloped interface. Solute redistribution, caused by thermoelectric magnetic convection (TEMC), responds to the changes in the interface shape. Because different typical length scales should be used in estimating the velocity of TEMC for planar, cellular, and dendritic interfaces, the maximum velocity of the convection ahead of the interface is obtained under different TMF intensities; correspondingly, leveling of the interface’s degree of slop varies with TMF.     

Relationship between nitrogen content in grapes and volatiles,namely heavy sulphur compounds,in wines

Ammonium salts were added to white grape musts, before alcoholic fermentation, in order to evaluate their influence on the heavy sulphur compound and aliphatic higher alcohol composition of resulting wines. Six grape musts were used (Trajadura, Pedernã, Loureiro, Azal Branco, Avesso and Alvarinho). Ammonium supplementation of Trajadura and Pedernã grape musts, with the highest nitrogen level, did not influence the content of heavy sulphur compounds and aliphatic higher alcohols in wines; however, the addition of ammonium salts to grape musts with low initial nitrogen content, such as Loureiro, Azal Branco and Avesso, led to a higher production of 1-propanol and a lower production of isoamyl alcohols and sulphur compounds, e.g. S-methyl thioacetate, 2-mercaptoethanol, acetic acid-3-(methylthio)propyl ester, 3-mercapto-1-propanol, 4-(methylthio)-1-butanol, 3-(ethylthio)-1-propanol, 3-methylthiopropionic acid and N-3-(methylthiopropyl)acetamide. For Alvarinho grape must, a decrease in sulphur compound concentrations in wines was only observed for 3-methylthiopropionic acid, acetic acid-3-(methylthio)propyl ester and 2-mercaptoethanol.     

Sentiment d'injustice subie, comportements transgressifs et légitimation chez des footballeurs.

The purpose of the present study was to demonstrate the effects of the undergone feeling of injustice on the adoption and justification of aggressive behaviours. Male soccer players (196) completed a questionnaire presenting fair or unfair situations. They had to choose one of the four proposed reactions (no aggression, verbal aggression, nonhurting physical aggression, hurting physical aggression) and to justify it on a five point Likert scale. The results of this study showed that players who were confronted with injustice chose more aggressive reactions than players who were not. Furthermore, all players, whatever the experimental condition, justified the adoption of unaggressive behaviours. However, a negative correlation between the chosen behaviour and its justification was found among players who were not confronted with injustice. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Adaptation et validation en langue Fran?aise d'une échelle de prise de décision.

The purpose of the present study was to evaluate the psychometric properties of the Melbourne Decision Making Questionnaire (MDMQ) in a French population. This questionnaire is based on the decisional conflict model proposed by Janis and Mann (1977). Four major decisional styles were identified by authors: vigilance, buck-passing, procrastination, and hypervigilance. Four hundred fifty-four participants took part in the study. Results of factor analysis and confirmatory factor analysis indicated that the MDMQ can be conceptualized on a four-factor model according to Mann et al. (1998). The reliability of the MDQM appeared to be satisfactory with good internal consistency. Even if mean scores obtained on each decisional style are lower than preceding studies, results of this study justify utilisation of MDQM with the French population. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Too upset to think: The interplay of borderline personality features, negative emotions, and social problem solving in the laboratory.

Borderline personality disorder (BPD) is associated with poor social problem solving and problems with emotion regulation. In this study, the social problem-solving performance of undergraduates with high (n = 26), mid (n = 32), or low (n = 29) levels of BPD features was assessed with the Social Problem-Solving Inventory—Revised and using the means-ends problem-solving procedure before and after a social rejection stressor. The high-BP group, but not the low-BP group, showed a significant reduction in relevant solutions to social problems and more inappropriate solutions following the negative emotion induction. Increases in self-reported negative emotions during the emotion induction mediated the relationship between BP features and reductions in social problem-solving performance. In addition, the high-BP group demonstrated trait deficits in social problem solving on the Social Problem-Solving Inventory—Revised. These findings suggest that future research must examine social problem solving under differing emotional conditions, and that clinical interventions to improve social problem solving among persons with BP features should focus on responses to emotional contexts. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Motivating reflection about health within the family: the use of goal setting and tailored feedback

It is widely acknowledged that obesity is a serious health issue. Despite governments?? campaigns and initiatives to raise the level of awareness, the proportion of adults classified as overweight or obese is increasing steadily. As a result, there has been a growing interest in Human Computer Interaction and User Modelling to study how to support health behaviour change. While most of the work to date has focused on individuals, medical research has shown that family engagement plays an important role on health behaviour. To consider the family context, we are developing technology that facilitates health discussions and encourages supportive behaviour within the family. We investigate how to motivate members of a family to reflect upon their lifestyle and think of ways in which they can make it healthier. In particular, we have looked at whether providing explicit goals and tailored feedback can have an impact. During a two week trial with families in which we explored these strategies, we found that setting a collective goal for the family influenced how much the family as a whole contributed, and that feedback increased significantly mothers?? participation. Our results also suggest that establishing a family goal encouraged families to work together and, in particular, to help each other find ways to be healthier. Finally, 76% of participants reported discussing the task with someone in their family, and, also discussing it together as a family (57%).     

A predictive microbiology approach for thermal inactivation of Hepatitis A virus in acidified berries

Hepatitis A virus (HAV) is a food-borne enteric virus responsible for outbreaks of hepatitis associated with consumption of raw vegetables. Soft fruits, such as red berries, exposed to faecal contamination are increasingly responsible for collective food-borne illnesses associated with HAV, when eaten raw or used in unprocessed foods. Heat is the most effective measure for the inactivation of HAV. Thermal treatments are used on fruits as a decontamination method, but they have to be adapted to product characteristics; indeed, factors such as sugar or pH may have an impact on the viral sensitivity to thermal treatments. A model was developed for the inactivation of HAV in red berries without supplemented sugar and with different pH values. Nonlinear inactivation curves in acidified raspberries were modelled using an integrated model, with a single equation nesting secondary models of temperature and pH in the primary model. Model predictions were then confronted to experimental results obtained in another laboratory on other berries with different pH values. Excellent predictions were obtained in most cases, while failed predictions provided safe results, with the model predicting higher residual virus titres than what was observed.