Does protein oxidation affect proteolysis in low sodium Chinese traditional bacon processing?

Area of Science:

• Food Science
• Meat Science
• Biochemistry

Background:

• Traditional Chinese bacon manufacturing relies on sodium chloride (NaCl), but high intake is a health concern.
• Developing low-sodium alternatives is crucial for public health and consumer demand.
• Understanding the impact of salt substitution on meat protein quality is essential.

Purpose of the Study:

• To investigate the effects of replacing NaCl with potassium chloride (KCl) on protein oxidation and proteolysis during low-sodium Chinese bacon production.
• To determine the interrelationship between protein oxidation and proteolysis under different KCl substitution levels.
• To assess the impact of KCl on the overall quality of Chinese bacon.

Main Methods:

• Bacon samples were prepared using four different salting treatments: 0%, 30%, 50%, and 70% KCl substitution for NaCl.
• Protein oxidation was assessed by measuring total carbonylation, thiol oxidation, and tryptophan fluorescence.
• Proteolysis was evaluated using non-protein nitrogen content, free amino acid analysis, and SDS-PAGE.

Main Results:

• Both protein oxidation and proteolysis occurred simultaneously during low-sodium Chinese bacon manufacturing.
• A 70% KCl substitution significantly promoted proteolysis.
• The 70% KCl replacement led to increased protein oxidation, evidenced by reduced tryptophan fluorescence and elevated total carbonyl content.
• A strong correlation was observed between protein oxidation and proteolysis.

Conclusions:

• Potassium chloride (KCl) substitution for sodium chloride (NaCl) in Chinese bacon manufacturing influences protein oxidation and proteolysis.
• Higher levels of KCl (up to 70%) can accelerate both protein breakdown and oxidation, potentially affecting bacon texture and flavor.
• The findings highlight a significant interrelationship between oxidation and proteolysis, crucial for developing improved low-sodium meat products.