Density-based Food Analysis Using a Smartphone

Abstract

Density is a crucial factor of interest in the food industry because it can reveal valuable information about the content and quality of food products. Traditionally, this physical property is quantified using a hydrometer or a pyncometer. However, the accuracy of analog instruments is limited by human error and more modern digital adaptations of such methods come with high monetary costs. Here, we present a lowcost, portable, and user-friendly platform for density-based analysis of liquid food samples of very small volumes (<10 µL) via magnetic levitation. The platform is fully compatible with an Android smartphone which collects magnified images and conducts automated density-based metric determination using a custom-designed Android application. Validity of the device was shown by measuring the density of oils (indicating fat content) and ethanol solutions (indicating alcohol content). This technique offers an accurate and low-cost alternative to current density measurement techniques for analysis of food quality for broad use in-home or in the food industry.