Dual-modulated anthocyanin-based freshness indicators with improved stability using 2,5-dihydroxybenzoic acid and
Hao Fang1, Limin Cao1, Jianxin Sui1
1State Key Laboratory of Marine Food Processing & Safety Control, College of Food Science and Engineering, Ocean University of China, Qingdao, Shandong 266003, China.
Food Chemistry
|April 26, 2026
Summary
A novel anthocyanin-based indicator patch, stabilized with a metal-organic framework (UiO-66-NH2) and 2,5-dihydroxybenzoic acid, offers reliable food freshness detection. This stable, pH-responsive patch accurately monitors spoilage indicators in seafood.
Area of Science:
- Food Science
- Materials Science
- Chemistry
Background:
- Anthocyanins are natural pigments with pH-indicating properties, ideal for intelligent food packaging.
- Their practical application is hindered by poor stability under environmental stress.
Purpose of the Study:
- To develop a highly stable intelligent indicator patch for food freshness monitoring.
- To enhance anthocyanin stability and responsiveness using a dual-modulation strategy.
Main Methods:
- Incorporation of UiO-66-NH2 (metal-organic framework) and 2,5-dihydroxybenzoic acid to stabilize anthocyanins.
- Evaluation of the indicator patch's stability, pH responsiveness, and selectivity to spoilage amines.
- Application of the patch to Litopenaeus vannamei (shrimp) and correlation of color change with TVB-N values.
Main Results:
- The optimized indicator patch demonstrated significantly enhanced anthocyanin stability, maintaining color integrity for over 30 days at ambient temperature.
- The patch exhibited excellent pH responsiveness and high selectivity to spoilage amines like ammonia.
- Color changes strongly correlated with TVB-N values (r > 0.93) in shrimp, accurately identifying freshness stages.
- High batch-to-batch reproducibility (RSD < 5%) and anti-interference capabilities were confirmed.
Conclusions:
- A feasible approach for commercializing stable anthocyanin-based freshness indicators for intelligent packaging was provided.
- The developed indicator patch offers a reliable and accurate method for real-time food freshness monitoring.
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