Home for Environmentally Responsible Engineers (HERE): Water Taste Test Challenge

As part of a co-curricular activity for students in the Home for Environmentally Responsible Engineering (HERE) program at Rose-Hulman Institute of Technology (RHIT), students conducted water taste tests to explore preferences of fellow students among various bottled and tap waters. The motivation behind this study stemmed from the high energy requirements and costs of producing bottled water when compared to the energy requirements and costs of producing tap water, as well as the plastic bottle waste added to landfills from water bottles that are not recycled. Here students administered a double-blind study in which participants tasted samples of four types of water: two bottled water samples (Aquafina and Ice Mountain) and two tap water samples (one of which underwent an additional filtration process post-tap). The samples were offered to the participants in random order. Participants completed a survey to answer questions regarding their typical water consumption (i.e. type of water they drink and their daily consumption amounts). They then chose their most and least preferred sample. Three trials of the taste test have been completed. Analyses show that there are statistically significant differences among most and least preferred samples. Chi-square analyses have been conducted to answer the question, “Is the true proportion of students most (least) preferring each type equal to 25%, or is the true proportion different than 25% for at least one type of water?” Additional testing was conducted to determine if most and least preferred water type is independent of stated preference for water type or amount of water consumed in a typical day. Finally, additional chi-square tests of independence were conducted to see if the most or least preferred sample is independent of the order in which the waters were tasted.