Determination of hedonic thresholds by varying three stimuli.

The Hedonic Threshold Methodology (HTM), through the determination of compromised acceptance threshold (CAT) and hedonic rejection threshold (HRT), has several applications by the food industry. In order to further increase the field of application of HTM, the objective was to use a mixture design in the Hedonic Threshold Methodology, to enable the determination of hedonic thresholds (CAT and HRT) by varying the intensity of three stimuli simultaneously. It was investigated how much it is possible to replace the NaCl content (1.8% flour weight basis) with two other ingredients (KCL/yeast extract or KCL/enzyme preparation), without compromising the acceptance (CAT) and without resulting in sensory rejection (HRT) of crackers. Reduction in the acceptance started to occur by reducing the NaCl content by around 64% (from 1.81% to 0.651%), with the addition of 1.149% KCl. Two combinations of KCl and yeast extract (1.783% and 0.017%, or 0.693% and 1.107%, respectively) allowed producing a cracker with no NaCl without sensory rejection. The reduction in acceptance also started to occur by reducing the NaCl content by around 40% (from 1.81% to 1.086%), with adding of 0.358% KCl and 0.356% enzyme preparation. A sensory rejection begins to occur by reducing the NaCl content by around 99% (1.81-0.012%), with the addition of 1.215% KCl and 0.573% enzyme preparation (transglutaminase). The use of the mixture design in HTM allowed the unprecedented determination of hedonic thresholds varying three stimuli. This expands the possibilities for applications of sensory thresholds.

How much can sodium chloride be substituted for potassium chloride without affecting the sensory acceptance of cracker-type biscuits?

Excessive sodium consumption is a worldwide public health concern. The substitution of sodium chloride (NaCl) for potassium chloride (KCl) has been adopted to reduce the sodium concentration in processed foods. The challenge is to make this substitution without affecting the sensory acceptance of foods. In this context, the objective was to determine from which concentrations the replacement of NaCl by KCl results in reduced acceptance (compromised acceptance threshold - CAT) and begins the sensory rejection (hedonic rejection threshold - HRT) of cracker-type biscuits. Using the hedonic thresholds methodology (HTM) by varying a stimulus, CAT and HRT were determined for the concentration of NaCl in crackers and, by varying two stimuli, CAT and HRT, for replacing NaCl with KCl in crackers were determined. Without the addition of KCl, the reduction in acceptance started to occur by reducing the NaCl content by around 60% (from 1.81% to 0.73%); and sensory rejection began to appear by reducing the NaCl content by approximately 93% (1.81% to 0.13%). Reduction in the acceptance started to occur by lowering the NaCl content by around 78% (from 1.81% to 0.397%), with the addition of 0.896% KCl. In addition, by adding KCl, it was possible to reduce 100% NaCl without sensory rejection of the crackers. With these results, cracker industries can reduce the sodium content of their products, contributing to the reduction of population salt intake.