Colorimetric biofilm sensor with anthocyanin for monitoring fresh pork spoilage

Abstract

The colorimetric biofilm sensor was prepared for monitoring of freshness pork based on natural composite polymer including agar, sodium alginate and polyvinyl alcohol mixed with anthocyanin as an indicator and coated on chromatographic paper. The anthocyanin was extracted from red cabbage by boiling with distilled water at 80 °C for 90 min and adjusted to pH 2. The colorimetric biofilm sensor mixed with anthocyanin extracts obviously a clear color response from pink to green at pH 2.0–11.0. The composite polymers can be enhancing the stability of anthocyanin extracts. The colorimetric biofilm sensor was stored at 4 °C in darkness has more color stability than room temperature for 30 days. The colorimetric biofilm sensor was evaluated by a test on monitoring pork spoilage, the color was changed from pink to orange when total volatile basic nitrogen (TVB–N) reached higher than the critical amount (25 mg N/100 g.). These results can be concluded that the development of colorimetric biofilm sensor could be used to monitor pork freshness.