Consumer acceptance of salt-reduced “soy sauce” foods over rapidly repeated exposure

The stability of the liking for salt reduced products was tested in a rapidly repeated exposure study using soup and bread (with ham). Salt was partially replaced by naturally brewed soy sauce. First, 44 consumers performed 5 two-alternative forced choice tests to establish the exchange rate (ER) at which table salt could be replaced with soy sauce without significantly changing overall taste intensity. Secondly, the same consumers rated their liking for 5 samples with varying table salt and/or soy sauce content to determine the optimal exchange rate (OER), which is the highest concentration of NaCl in products that can be replaced with soy sauce without significant losses in both overall taste intensity and product liking. Finally, a new group of 64 consumers performed rapidly repeated exposure tests with two variants per product type: the non-salt-reduced standard variant (A) and a salt/soy sauce variant (B) based on the OER (NaCl reduction soup: 24.4%; bread & ham: 38.9%). Repeated exposure to the soy sauce variant had a significant to very significant positive effect on the liking for the products in all groups of subjects with the exception of a small group that did not like the soy sauce variant of bread. The influence of the rapidly repeated exposure was interpreted in terms of the optimal arousal theory. The results also demonstrated the importance of determining the ER, the OER and the development of preference over repeated exposure in the developed three-stage procedure.