Fruit juice continues to be a popular and refreshing beverage and can be a better nutritional alternative than typical carbonated beverages. The nutritional content of 100% fruit juices is derived from the fruit itself, and these valuable nutrients are displayed on the detailed bottle label. Customers use these labels to inform themselves on the nutritional content of the juice and for comparative shopping. While these labels provide a valuable reference for customers, they are also legally required in North America, and the veracity of these labels is the responsibility of the manufacturer.
For food manufacturers and processors, it is imperative that there is a means to quantify the content of food products, including micro-nutrients, for both safety and quality reasons along with regulatory label-claim requirements. Screening raw materials for elemental contaminants prior to use and then confirming the micronutrient content of the final product are two basic examples of the benefits of analytical testing. Accurate and precise analysis can also help improve the production process by providing rapid results and allowing optimization of the production process to maximize nutrient yield or production volume where appropriate.
Inductively coupled plasma optical emission spectroscopy (ICP-OES) is generally favored in a multi-element analytical environment with detection capabilities appropriate for nutritional analysis as demonstrated in this application. Flame atomic absorption (AA) systems, which provide cost savings, simplicity, and single-element analytical speed, can be attractive alternatives1. However, measuring a large number of elements by Flame AA requires each sample to be re-analyzed individually for each element, which can eliminate the speed advantage of Flame AA.
This work will focus on the analysis of micro-nutrients in a variety of commercial juice products using a PerkinElmer Avio™ 200 ICP-OES with sample preparation performed using a PerkinElmer Titan MPS™ Microwave Sample Preparation System.