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Short communication: Reducing agents attenuate methylglyoxal-based browning in Parmesan cheese
1Department of Food Science, Cornell University, Ithaca, NY 14853.
Journal of Dairy Science
|August 21, 2013
Summary
Adding reducing agents like sodium bisulfite and glutathione effectively prevents methylglyoxal-induced browning in Parmesan cheese. This study explored methods to maintain cheese quality by inhibiting color changes.
Area of Science:
- Food Science
- Microbiology
- Organic Chemistry
Background:
- Methylglyoxal, a microbial metabolite, causes undesirable brown pigmentation and volatile compound formation in cheese.
- Controlling methylglyoxal is crucial for maintaining the visual appeal and flavor profile of cheese products.
Purpose of the Study:
- To investigate the efficacy of various reducing agents in preventing methylglyoxal-induced browning in Parmesan cheese.
- To evaluate the impact of different molar ratios of reducing agents on browning inhibition.
Main Methods:
- Parmesan cheese samples were treated with methylglyoxal and reducing agents (sodium bisulfite, glutathione, erythorbate) at specified molar ratios.
- Colorimetric analysis was performed over 6 days at 10 °C to quantify the degree of browning.
- The chemical mechanism involving nucleophilic attack on methylglyoxal's carbonyl carbons was proposed.
Main Results:
- Sodium bisulfite and glutathione significantly inhibited methylglyoxal-induced browning compared to the control.
- Erythorbate showed less inhibition than sodium bisulfite and glutathione but still reduced browning compared to the control.
- The effectiveness of inhibition correlated with the reducing agents' nucleophilic properties.
Conclusions:
- Sodium bisulfite and glutathione are effective agents for preventing methylglyoxal-induced browning in Parmesan cheese.
- Reducing agents can mitigate undesirable color changes in cheese by reacting with methylglyoxal.
- This research offers practical strategies for improving cheese quality and shelf life.
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