Dysphagia thickeners in context of use: Changes in thickened drinks viscosity and thixotropy with temperature and time of consumption.

Dysphagia patients might need to thicken drinks. The viscosity of these thickened drinks varies among commercial thickeners and drinks compromising the ingesta safety. The aim of this study was to investigate how temperature and resting time affect the rheological properties of thickened drinks. Four commercial thickeners were used to thicken water, coffee, orange juice, and milk at two concentration levels used in dysphagia drinks (nectar and pudding). To study the effect of temperature, flow curves of thickened drinks at 10°C and 50°C were obtained and to study the effect of resting time, flow curves of thickened drinks at 25°C were obtained at different times (0, 30, and 60 min). All samples displayed shear-thinning and time-dependent behavior (thixotropy or antithixotropy). The effect of temperature on viscosity values and relative thixotropic area (RTA) depended on the thickener and the drink. Overall, apparent viscosity showed higher values at 50°C than 10°C, especially in thickeners containing starch and in drinks with higher soluble solids (milk and orange juice). This was attributed to the water absorption of pregelatinized starch granules favored by temperature. Antithixotropy was mainly observed at pudding concentration for the starch-containing thickeners, and decreased with temperature. The effect of resting time on apparent viscosity and RTA depended also on the drink and thickener. Mostly, apparent viscosity values increased with resting time and antithixotropic behavior decreased. Both effects, increase in viscosity and decrease of antithixotropy with time, indicated that thickening action was being developed over the resting time.

Are mixed meat and vegetable protein products good alternatives for reducing meat consumption? A case study with burgers.

The principal motivations for the worldwide trend towards reducing meat consumption are health, the environment and animal welfare. The present study investigated the willingness of omnivores to introduce mixed (beef-vegetable protein) and 100% vegetable protein products into their diet. The participants (n = 251) were young adult omnivores who consumed meat at least once a week. The stimuli were images of six different products representing two beef burgers, two mixed-protein burgers (50% beef and 50% seitan or soy) and two 100% vegetable protein burgers (seitan and soy). The participants were asked to write down spontaneous associations with each product (Word Association technique) and score their expected liking and purchase intention for them. In addition, they completed a questionnaire (36 statements) to evaluate their attitude towards meat reduction, considering six aspects: diet, habits, ethics, hedonism, health, and the environment. According to their response to these statements, they were classified into three attitude groups: anti- (ANTI, n = 106), intermediate- (INTERM, n = 89), and pro- (PRO, n = 56) meat reduction. All the participants expected to like the 100% beef burger most, the PRO group expected to like all six products to a similar degree and the ANTI group expected to like the mixed product significantly more than the 100% vegetable product, indicating that the introduction of mixed proteins could be a small first step towards meat reduction for those most attached to meat. The associations elicited by the different burgers were mostly the same but were mentioned with different frequencies, which also depended on the attitude group. These distinctive association patterns showed clear connections to the motives underlying each group's attitude towards meat reduction. It may be concluded that mixed products would be a reliable although timid option for consumers who are attached to meat to reduce their meat intake, while any of the products containing vegetable proteins would be an option for consumers who are more favourable towards meat reduction.

Potential Impact of Oat Ingredient Type on Oral Fragmentation of Biscuits and Oro-Digestibility of Starch-An In Vitro Approach.

The aim of the present study was to determine how variation in the biscuit matrix affects both the degree of in vitro fragmentation and the starch hydrolysis that occurs during the oral phase of digestion. Using three different oat ingredient types (oat flour, small flakes, and big flakes) and baking powder (or none), six biscuits with different matrices were obtained. The instrumental texture (force and sound measurements) of the biscuits was analyzed. The samples were then subjected to in vitro fragmentation. The particle size distribution and in vitro oral starch hydrolysis over time of the fragmented samples were evaluated. The results showed that the samples presented different fragmentation patterns, mainly depending on the oat ingredient type, which could be related to their differences in texture. The biscuits made with oat flour were harder, had a more compact matrix and showed more irregular fragmentation and a higher percentage area of small particles than those made with big oat flakes, which were more fragile and crumbly. The highest degree of starch hydrolysis corresponded to the biscuits made with flour. Conclusions: Differences in the mechanical properties of the biscuit matrix, in this case due to differences in the oat ingredient, play a role in the in vitro fragmentation pattern of biscuits and in the oral phase of starch hydrolysis.

Development of a novel smoke-flavoured salmon product by sodium replacement using water vapour permeable bags.

BACKGROUND: Food manufacturers need to reduce sodium content to meet consumer and public health demands. In the present study, the use of sodium-free (SF) salt and KCl to develop a novel smoke-flavoured salmon product with reduced sodium content was evaluated. Fifty percent of NaCl was replaced with 50% of SF salt or 50% KCl in the salmon smoke-flavouring process, which was carried out using water vapour permeable bags. RESULTS: Triangle tests showed that samples with either SF salt or KCl were statistically similar to the control samples (100% NaCl). Because no sensorial advantage in using SF salt was found compared to KCl and given the lower price of KCl, the KCl-NaCl samples were selected for the next phase. The changes of physicochemical and microbial parameters in smoke-flavoured salmon during 42 days showed that partial replacement of NaCl with KCl did not significantly affect the quality and shelf-life of smoke-flavoured salmon, which was over 42 days. CONCLUSION: Smoke-flavoured salmon with 37% sodium reduction was developed without affecting the sensory features and shelf-life. This is an interesting option for reducing the sodium content in such products to help meet the needs set by both health authorities and consumers. © 2017 Society of Chemical Industry.

Evaluation of sea bream (Sparus aurata) shelf life using an optoelectronic nose.

A new optoelectronic nose for the shelf-life assessment of fresh sea bream in cold storage has been developed. The chromogenic array used eight sensing materials (based on aluminium oxide and silica gel) containing pH indicators, Lewis acids and an oxidation-reduction indicator. The colour changes of the sensor array were characteristic of sea bream spoilage. Colour modulations were measured on day 0 and for the samples held in cold storage for 2, 4, 7, 9 and 11 days. Determination of moisture content, pH, total volatile basic nitrogen (TVB-N), drip loss, ATP-related compounds and K(1)-value and microbial (mesophilic bacteria and Enterobacteriaceae) analyses were carried out on the same days. The changes in the chromogenic arrays data were processed by statistical analysis (PCA). Moreover, PLS statistical studies allowed the creation of models to correlate the chromogenic data with concentrations of mesophilic and Enterobacteriaceae. The results suggest the feasibility of this system to help develop optoelectronic noses for fish freshness monitoring.