P3-155 Development of Whey Protein-based Carbon Dioxide Indicator to Monitor Food Freshness

Wednesday, July 31, 2013
Exhibit Hall (Charlotte Convention Center)
Kyuho Lee, Sejong University, Seoul, South Korea
Keehyuk Sohn, Sejong University, Seoul, South Korea
Sanghoon Ko, Sejong University, Seoul, South Korea
Introduction: Partial pressure of carbon dioxide (CO2) can be used as an indicator of food quality in a food package as microbial spoilage or respiration of agricultural products typically results in CO2 accumulation. Therefore, a visual CO2 indicator provides to easily check the food quality, simply by changing transparency depending on the CO2 concentration in headspace of food package.

Purpose: The aim of this study is to develop whey protein isolate (WPI) based carbon dioxide indicator, and determination of its physicochemical properties.

Methods: WPI powder was added at the level of 0.1, 0.3, 0.5, 1, 2 and 4 g in 100 ml of distilled water, and the solution was stirred for 1 h after adjusting pH to 7.0 by 1 M HCl and NaOH. Then, the solutions were stored under 100 % CO2 atmosphere. Thereafter, the solutions were measured in terms of pH and transparency.

Results: Changes in transparency of 0.1, 0.3, 0.5, 1, 2 and 4% WPI indicator solutions were 67.2, 66.0, 21.3, 31.7, 13.5 and 3.1%, respectively. A 0.1% WPI indicator solution exhibited the highest transparency change, but a 0.3% WPI indicator solution was selected because it exhibited optimal visual change in turbidity.

Significance: From these results, we can conclude that the change of transparency and pH decreases as concentration of WPI increases. WPI-based indicators can be used for various food packages containing agricultural products and processed foods which can accumulate different levels of CO2 by respiration and fermentation during storage.