The purpose of this research was to evaluate the correlation between obesity, threshold of salty taste, optimal saltiness and blood pressure in middle school students in a fishing village. The subjects were 115 boys and 103 girls in middle school in a fishing village. The BMI index and systolic and diastolic blood pressures of subjects were measured, and the subjects were divided into a normal and obese group according to their BMI. The threshold of salty taste and salt preference for a semisolid dish (steamed egg dish), liquid dish (bean sprout soup), and a solid dish (raw radish salad), were estimated by sensory evaluation. Calorie intake was measured using the weighing plate method. The boys in the obese group showed significantly higher systolic and diastolic blood pressures than those in the normal, but girls did not. Furthermore, calorie intakes of the boys in the obese group were significantly higher than those in the normal group, but this was not shown in girls. On the threshold of salty taste, both boys and girls in the obese group needed higher concentration of salt than those in the normal group. The threshold of salty taste were significantly positively correlated with systolic pressure and diastolic pressure in boys. Regarding the salt preference in the steamed egg dish, bean-sprout soup, and raw radish salad, both boys and girls in the obese group preferred higher concentrations. The higher concentration they preferred, the higher the systolic and diastolic pressures were in boys, but only systolic blood pressure was higher in girls. From these results, it is evident that a nutritional education program is needed in school to help restricting middle school students salt consumption and decreasing obesity to prevent hypertension.

The effect of color, as measured on the spectrometer, on the 4 basic tastes(sweet, salty, sour & bitter) perception of a series of colored and no-flavored solutions was quantified by 16 taste panel using magnitude estimation without modulus. The regression lines for each colored series were found to differ indicating that color had a significant effect on sweetness, sourness and bitterness. A sucrose level of 4.0%, a citric acid level of 0.05%, and a nicotinamide level of 0.08% maximized the effect of color on taste's perception and its acceptability. Although color tended to confuse the perception of saltiness, this effect was not significant except for yellow solutions.