Hedonic thresholds and ideal sodium content reduction of bread loaves

Abstract

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.