Antioxidant compounds and pH-adjusting agents in food products: operational mechanisms and health implications of their use

Antioxidants and acidity regulators serve as indispensable functional additives in contemporary food technology and preservation. Food-grade antioxidants halt the radical-mediated peroxidation of lipids, thereby safeguarding polyunsaturated fatty acids against rancidity, oxidative off-flavors, and the degradation of fat-soluble vitamins. Concurrently, pH-adjusting acidity regulators (such as citric acid E330, lactic acid E270, malic acid E296, and tartaric acid E334) modulate and stabilize ambient pH levels. Maintaining an acidic substrate below pH 4.5 creates an inhospitable barrier against microbial pathogens such as Clostridium botulinum, while optimizing enzymatic stability and color retention.

Antioxidants utilized across the food industry are classified into nature-identical extracts and synthetic chemical stabilizers. Naturally derived additives such as mixed tocopherols (vitamin E, E306–E309), ascorbic acid (vitamin C, E300), and carotenoids are biologically inert or beneficial, contributing to physiological radical scavenging and cellular defense against oxidative stress. In contrast, synthetic lipophilic antioxidants including butylated hydroxyanisole (BHA, E320), butylated hydroxytoluene (BHT, E321), and propyl gallate (E310) are governed by strict Acceptable Daily Intake (ADI) thresholds. In excessive quantities, these synthetic compounds have been associated with pseudoallergic dermal reactions, gastric irritation, and metabolic hepatic strain.

The overwhelming majority of approved acidity regulators, including citrates (E330–E333), lactates (E270), and acetates (E260), constitute physiological intermediates of human cellular metabolism (such as the Krebs tricarboxylic acid cycle). In standard technological concentrations, they undergo rapid biological oxidation to carbon dioxide and water without clinical toxicity. Caution is primarily advised regarding inorganic phosphates and phosphoric acid (E338–E341), ubiquitous in dark colas and processed meats. Excessive dietary phosphate consumption disrupts the parathyroid-vitamin D endocrine axis, contributing to impaired bone mineralization and promoting vascular calcification.