Conformational changes of polymers in model batter systems

Cake batters - made of flour, egg, sugar and fat - are complex systems. Ingredients interactions and their impact on protein secondary structure and starch conformational structures were studied in model batter systems using Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy. The results showed the possibility of using the pregelatinized starch without affecting protein conformation. The estimation of protein secondary structure highlighted the prevalence of \u3b1-helical structures in the model batter system, while \u3b2-sheets are predominant in flour systems as known in dough systems. The protein conformation in batter system is related to fat-protein interactions and could explain fat functionality in the final product. Starch crystallinity increased when each ingredient - except for pregelatinized starches - was added to the flour. Changes in starch conformation could be related to the redistribution of water between the batter ingredients. The overall results highlighted the importance of ingredients on the structural conformation of the batter polymers - starch and proteins - which could be the key factor to understand the functional properties of the batter

Shared decision making and experiences of patients with long-term conditions : has anything changed?

Background Medication problems among patients with long-term conditions (LTCs) are well documented. Measures to support LTC management include: medicine optimisation services by community pharmacists such as the Medicine Use Review (MUR) service in England, implementation of shared decision making (SDM), and the availability of rapid access clinics in primary care. This study aimed to investigate the experience of patients with LTCs about SDM including medication counselling and their awareness of community pharmacy medication review services. Methods A mixed research method with a purposive sampling strategy to recruit patients was used. The quantitative phase involved two surveys, each requiring a sample size of 319. The first was related to SDM experience and the second to medication counselling at discharge. Patients were recruited from medical wards at St. George’s and Croydon University Hospitals.The qualitative phase involved semi-structured interviews with 18 respiratory patients attending a community rapid access clinic. Interviews were audio-recorded and transcribed verbatim. Thematic analysis using inductive/deductive approaches was employed. Survey results were analysed using descriptive statistics. Results The response rate for surveys 1 and 2 survey was 79% (n = 357/450) and 68.5% (240/350) respectively. Survey 1 showed that although 70% of patients had changes made to their medications, only 40% were consulted about them and two-thirds (62.2%) wanted to be involved in SDM. In survey 2, 37.5% of patients thought that medication counselling could be improved. Most patients (88.8%) were interested in receiving the MUR service; however 83% were not aware of it. The majority (57.9%) were interested in receiving their discharge medications from community pharmacies. The interviews generated three themes; lack of patient-centered care and SDM, minimal medication counselling provided and lack of awareness about the MUR service. Conclusion Although patients wanted to take part in SDM, yet SDM and medication counselling are not optimally provided. Patients were interested in the MUR service; however there was lack of awareness and referral for this service. The results propose community pharmacy as a new care pathway for medication supply and counselling post discharge. This promotes a change of health policy whereby community-based services are used to enhance the performance of acute hospitals

Knowledge and awareness of the general public and perception of pharmacists about antibiotic resistance

Background Antibiotic resistance (AR) continues to be a serious problem. Many factors contribute to AR, including inappropriate use of antibiotics, in which both healthcare professionals and patients play a contributing role. This study aimed to assess the awareness and knowledge of antibiotic usage and AR among the general public (in affluent and deprived areas) and community pharmacists' (CPs') in Greater London. Methods A cross-sectional survey involving members of the public was conducted between July 2014 and February 2015. Stage one involved members of the public (N = 384) residing in affluent areas of London. The second stage targeted public (N = 384) in deprived areas of London. In addition, CPs (N = 240) across the same areas were also surveyed. Data analysis was performed using Microsoft Excel and SPSS Software packages. Results Response rate: 36% (n = 139/384) and 57% (n = 220/384) and 25% (n = 60/240) of public residing in affluent areas, deprived areas and of CPs respectively was achieved. Definitive trends in knowledge of how antibiotics work could not be drawn to distinguish between affluent and deprived areas. However, public respondents residing in affluent areas possessed better understanding of AR and prudent use of antibiotics, and this was statistically significant in both cases (p < 0.05). Exposure to an antibiotic campaign (32% in affluent areas, 17% in deprived areas) did not raise public respondents' knowledge on AR and only partially raised their general knowledge on antibiotics usage. Only 20% of public residing in deprived areas received counselling from a CP, among them 74% had an antibiotic prescribed on at least one previous occasion. Those who received counselling displayed better knowledge about concordance/adherence with respect to antibiotic usage (p < 0.05) whereas exposure to an antibiotic campaign made no significant impact on knowledge about concordance/adherence. Conclusion The study highlights that there has been no change in the status quo with respect to awareness of antibiotic usage and AR even after the implementation of several awareness campaigns in England. Those who benefited from CP counselling showed a significant better knowledge towards prudent antibiotic usage which stresses the importance of CPs' counselling on antibiotic prescription

Conformational changes of polymers in model batter systems

Cake batters are complex systems with their higher content in sugar and fat in compare to other baking products. The interactions between the ingredients affect the structure of the end product. The objective of this work is to understand the protein-lipid-starch interactions and their impact on protein and starch conformational changes. A model system approach was used by mixing flour, pregelatinized wheat starch (PWS), eggs, sugar and fat in the same ratios as in the real cake batter. Protein secondary structure and starch conformational changes were determined by the ATR-FTIR spectroscopy. The FTIR spectra showed that the addition of the fat to flour increased the alpha-helical structures (from 16% to 35% of total) and decreased the beta-sheet structures (from 49% to 22% of total). This could be related to the decrease of the interactions among hydrophilic molecules by fat addition. While the eggs addition increased the beta-sheets (56%) at the expense of unordered structures due to eggs proteins-gluten interaction. When fat and eggs were added together, the fat effect on protein conformation was more pronounced decreasing the beta-sheet structures to 38%. The beta-sheet structures slightly increased when 20% of flour was replaced by the PWS. Whereas the effect of the PWS was more important on starch structures. The intensity ratios of the crystalline starch bands at 1047cm-1 and 1035 cm-1 were 0.91\ub10.02 and 0.84\ub10.02 for flour and flour+PWS mixtures respectively. The decrease in crystallinity could be due to the interaction between water and the pregelatinized starch which promoted more amorphous structure. This study revealed the important impact of batter ingredient interactions and the effect of using the PWS on proteins and starch structures which could be the key factor to enhance the cake quality

Role of ingredient interactions on structural and physycal characteristics of cake batter

Cake batter is a dispersion of macromolecular biopolymers. Starch and proteins play a key role in determining the structure, the rheology and other physical properties, as well as the sensory perception of the finished product. Furthermore, the texture of the cake depends on the formulation, the aeration of batter, the batter-crumb transition and its stability after baking. To control the quality of this finished product, it is essential to understand the effects of the ingredients on batter properties during mixing and baking. This work is devoted to investigate the effect of interactions of the ingredients on protein and starch features. Protein secondary structure and hydrophobicity were evaluated by Attenuated total reflectance-Fourier Transform Infrared (ATR-FTIR) and Fluorescence (FS) spectroscopies, respectively. Regarding starch, thermal and pasting properties were investigated by differential scanning calorimetry (DSC) and MicoViscoAmylograph (MVAG), respectively. The work was done on both model and real batter systems. ATR-FTIR spectra showed that fat addition greatly affected protein conformation, and specifically alpha-helix structures, rather than the other ingredients (e.g eggs, sugar, pregelatinized starch). This result shows the importance of the fat-proteins interactions that could result in a poor development of the protein network by increasing alpha-helix structures. FS results showed that the changes in protein hydophobicity, in the final model system (batter),was more related to egg and sugar addition rather than to the other ingredients such as the fat. These changes are related to the exposure of tryptophan to more hydrophobic environment by egg and sugar presence. During baking, interactions among ingredients affected the melting point of fat, the denaturation of proteins and batter-crumb transition that moves towards higher temperatures, as determined by DSC. Finally, during cooling, the formation of the starch and proteins gel measured by MVAG controlled the final viscosity reached during cooling which contributes to the texture of the material of the cell wall of the finished product. This confirms that starch and proteins play an important role in the final structure of the finished product. In conclusion, this work highlited the impact of fat on protein conformation in batter. While the competition between ingredients on water controlled phase transitions during cake batter baking which is fundamental to explain batter-crumb transition and consquently the finished product quality

Monitoring changes in crust and crumb of cakes after baking: relation to their microstructures

Cakes, as the majority of bakery products, are characterized by two different structures: crumb (internal part) and crust (external part). The physicochemical properties of crumb and crust in cakes have not been yet studied. This work focused on starch and protein characteristics in cake crumb and crust after baking (2h) using Micro-Visco-Amylograph (MVAG), Fourier Transform Infrared (FTIR) spectroscopy, Fluorescence spectroscopy, and Light Microscopy (LM). MVAG profiles showed that crumb has higher pasting temperature and lower peak viscosity than crust. Setback value, which is related to the ability of the amylose chains to reassociate and form a gel, was higher in crust than in crumb (600 and 500 mPa*s, respectively) giving a firmer gel in crust than in crumb. FTIR spectra showed that the starch crystallinity ratio, the intensity ratio of crystalline (1047 cm-1) and amorphous (1022 cm-1) bands, was higher in crust than in crumb (1.07\ub10.01 and 1.05\ub10.01, respectively) suggesting different retrogradation extents of starch polymers during cooling. Regarding proteins, FTIR spectra showed that beta-sheet structures were higher in crumb than in crust (10% and 4%, respectively) which could be explained by the higher water content in crumb than in crust. Fluorescence spectroscopy showed that crumb has higher tryptophan emission than crust (250 and 75 AU, respectively) probably related to the difference in water redistribution between crust and crumb. LM showed that starch granules were not gelatinized in crust due to its fast baking rate. This study showed that the changes taking place in cakes after baking could come from the difference between crumb and crust properties (starch gelatinization and retrogradation and water distribution) which are not clear enough by textural analysis. The role of crust and crumb during storage on cake quality needs to be investigated

Visualisation of cakes differing in oil content with magnetic resonance imaging

Magnetic resonance imaging (MRI) is a non-invasive imaging technique that can visualise samples' interior by using the signal coming from mobile protons. The aim of this study was to examine the effects of oil content and peanut/raisin addition on cake quality and to illustrate the power of MRI in analysis of moisture and oil distribution. For this purpose, MR images were acquired with a spin echo sequence and relaxation times T-1 and T-2, and moisture content and firmness of cakes were measured. High oil cakes (HOC) had higher moisture content and lower firmness than low oil cakes (LOC). However, addition of raisin/peanut did not affect the firmness of cakes significantly. In MR images, HOC cake crumb, owing to its higher oil content, displayed larger signal intensities. Signal acquired from different slices demonstrated an increase in moisture content from crust to centre of the cakes. Peanut and raisin signals were suppressed in fat and water suppression sequences, respectively. Significant correlation between transverse relaxation time (T-2a) and oil content (R-2 = 0.99) was found. Moreover, longitudinal relaxation time (T-1) was found to be strongly correlated with moisture content (R-2 = 0.99). The results demonstrated MRI's power as an accurate and non-invasive analysis method in baking