Testing for sensory threshold in drinking water with added calcium: a first step towards developing a calcium fortified water

Abstract

Background: Food fortification is an effective strategy that has been recommended for improving population calcium inadequate intakes. Increasing calcium concentration of water has been proposed as a possible strategy to improve calcium intake. The objective of this study was to determine the sensory threshold of different calcium salts added to drinking water using survival analysis. Methods: We performed the triangle test methodology for samples of water with added calcium using three different calcium salts: calcium chloride, calcium gluconate and calcium lactate. For each salt, a panel of 54 consumers tested seven batches of three water samples. Data were adjusted for chance and sensory threshold was estimated using the survival methodology and a discrimination of 50%. Results: The threshold value estimation for calcium gluconate was 587 ± 131 mg/L of water, corresponding to 25% discrimination, for calcium lactate was 676 ± 186 mg/L, corresponding to 50% discrimination, and for calcium chloride was 291 ± 73 mg/L, corresponding to 50% discrimination. Conclusions: These results show that water with calcium added in different salts and up to a concentration of 500 mg of calcium/L of water is feasible. The calcium salt allowing the highest calcium concentration with the lowest perceived changes in taste was calcium gluconate. Future studies need to explore stability and acceptability over longer periods of time.

Calcium concentration of drinking water to improve calcium intake: A simulation study

“…Also, supplementation may not be adequate for small children. 15,39 Adding calcium to water in combination with other strategies, such as food fortification, should be evaluated specifically for each population. 2,11,13 While planning an intervention to improve calcium intake in the population, vitamin D status should be considered.…”

“…[11][12][13] A food fortification vehicle requires reaching the target population while ensuring that its promotion can be synergized with efforts to improve diet. 2,14,15 Water has the advantage of being universally consumed and promoting the consumption of water can be a part of public health strategies for healthier diets. 16,17 We have previously simulated the impact of different calcium concentrations of water using individual food intake data from six countries by assessing the gap between dietary calcium intake and recommendations.…”

“…17 Afterward, following a standardized methodology survival analysis, we evaluated the sensory threshold taste of water with different levels of added calcium and found that the taste threshold is high and could provide a margin to increase the calcium concentration of water without changing the perceived taste. 15 Using bottled table water (filtered, dechlorinated, ozone-purified tap water that is commercially distributed in containers), we estimated that the taste threshold for calcium gluconate was 587 ± 131 mg of elemental calcium per liter of water, which corresponded to 25% discrimination. The taste threshold for calcium lactate was 676 ± 186 mg of elemental calcium per liter, and for calcium chloride, it was 291 ± 73 mg of elemental calcium per liter, corresponding to 50% discrimination.…”

Including calcium‐fortified water or flour in modeled diets based on local foods could improve calcium intake for women, adolescent girls, and young children in Bangladesh, Uganda, and Guatemala

“…Using a consumer panel of 54 individuals from Argentina, a recent acceptability study of three different calcium salts added to bottled water found that the sensory threshold for taste was 587 ± 131 mg/L of water for calcium gluconate, 676 ± 186 mg/L for calcium lactate, and 291 ± 73 mg/L for calcium chloride. 21 Assuming it can be made safe and accessible and that sensory acceptability findings from this small sample in Argentina would apply in other countries, drinking water could potentially be a good alternative vehicle to improve calcium in the diet. [24][25][26][27] This study, based on simulated diets using dietary data from the overall population, explored the potential of calcium-fortified wheat flour and water to complement the FBRs of local food sources of calcium in reaching the daily recommended Ca PRIs of four population groups (12-to 23-month-old and 4-to 6-year-old young children, adolescent girls, and NPNB women) across Bangladesh, Guatemala, and Uganda, where previous analysis showed that it was difficult or not possible to meet calcium intake targets using diets based on local foods alone.…”

“…Specific details on the mineral composition of location-specific drinking water are limited and usually missing in chemical composition tables, which creates challenges to assess the contribution of water on mineral intake. 20,21 Calcium levels in drinking water regulations are usually expressed in terms of a maximum level of water hardness. 22,23 Calcium bioavailability in water is high, similar to or higher than in dairy products.…”