Revisão: metodologias para análise da sensibilidade gustativa ao sal

Hedonic thresholds and ideal sodium content reduction of bread loaves

Global public policies have advocated strategies for reducing sodium consumption due to the high incidence of non-communicable chronic diseases (NCDs) worldwide. The objectives of this study were to identify the bread loaves sodium content considered as ideal by the consumers and determine hedonic thresholds. In this descriptive cross-sectional study, 114 consumers evaluated the ideal sodium content in bread loaves by the Just About Right (JAR) test, (first sensorial stage) studying four decreased levels of sodium (10%, 20%, 30%, 40%) from the mean values observed from bread in 11 food composition tables from various regions of the world, and Brazil. This ideal sodium content was used as the control in pairwise acceptance tests with five other reduced-sodium samples of bread loaves (10%, 30%, 50%, 70%, 100% of reduction from the control), and hedonic threshold tests were performed with 156 consumers (a second stage sensorial test of five sessions). The data from the JAR were analyzed by a regression analysis graph and correlated with the consumption of salt and family income range by a Principal Component Analysis with a 5% significance level. In the Hedonic Threshold tests, each paired session was analyzed by Student's t-test (test t), and an adjusted regression graph was built. The Compromised Acceptance Threshold (CAT) was performed, where the calculated t corresponded to the tabulated t. In the Hedonic Rejection Threshold (HRT), the hedonic scale five ("indifferent" term) was considered. The average sodium content of bread marketed in different regions of the world was 457 mg Na/100 g of bread, and the ideal sodium content observed was 395 mg Na/100 g of bread. The gender, age and income family rates as well as attitudes and knowledge regarding the salt consumption of the trial consumers were not directly related to the evaluations of the bread loaves in the JAR test, according to the Principal Components Analysis at p ≤ 0.05. From this ideal content, a 42% reduction was possible according to the CAT test (267 mg Na/100 g of bread), and more reductions were acceptable until an 85% (to 58 mg Na/100 g of bread) reduction, as the samples began to be rejected according to HRT test. These findings demonstrated that this methodology can be applied to sodium reduction product formulations and bread as a food matrix. With this kind of methodology, it is possible to provide to the bakery industry a methodology to know a safe region to work on food reformulations and subsidize the formulation of new products without compromising consumer acceptability, in addition to meeting the demand for safer food.

Impact of the severity of dementia due to Alzheimer's disease on the gustatory sensitivity of older persons

OBJECTIVE

To evaluate the association between the severity of dementia and taste recognition abilities in older persons with Alzheimer's disease (AD).

METHODS

Anthropometric measurements were performed and body mass index was used to determine the nutritional status. The taste strips were used to test gustatory functions of the five basic tastes (sweet, salty, sour, bitter and umami).

RESULTS

A total of 30 healthy younger subjects, 30 healthy older subjects, 37 with mild stage AD and 23 with moderate stage AD were recruited. The older subjects with moderate AD showed a significant reduction of taste, less recognition of bitter and salty taste (score: 10.6 ± 2.6; 2.6 ± 0.9; 1.7 ± 1.5) when compared to older people without cognitive impairment (score: 13.3 ± 1.8; 3.4 ± 0.9; 3.2 ± 0.9), and less recognition of sweet taste (score: 2.9 ± 1.2) when compared to subjects with mild stage AD (score: 3.6 ± 0.8). Impaired recognition of salty taste was detected since the early stages of AD. Among the factors that possibly influence gustatory function, a significant correlation was detected between taste ability and age, medication intake, mini-mental state examination and the nutritional status.

CONCLUSION

The severity of dementia is directly associated with greater impairment of taste sensitivity, especially among older subjects with moderate stage disease.

Association between Taste Sensitivity and Self-Reported and Objective Measures of Salt Intake among Hypertensive and Normotensive Individuals

This study investigated the gustatory threshold for salt and its relationship with dietary salt intake among hypertensive (n = 54) and normotensive (n = 54) subjects. Salt intake was evaluated through 24-hour urinary sodium excretion and self-reported measures (discretionary salt, Sodium- Food Frequence Questionnaire (Na-FFQ), and 24-hour recall). Detection and recognition thresholds were higher among hypertensive subjects, as well as the total sodium intake. Detection and recognition thresholds were positively related to discretionary salt and total intake of the group as whole. Hypertensive and normotensive subjects presented positive correlations between taste sensitivity and the different measures of salt intake. To conclude, a positive correlation exists between taste threshold and salt intake and both seem to be higher among hypertensive subjects. The combined use of methods of self-report and assessment of taste thresholds can be useful in health promotion and rehabilitation programs, by screening subjects at higher risk of elevated salt intake and the critical dietary behaviors to be targeted as well to evaluate the result of targeted interventions.