Protective effects of biquinho pepper as a natural antioxidant against cholesterol oxidation in mayonnaise during refrigerated storage

Mayonnaise is a popular creamy sauce highly susceptible to lipid oxidation, which can compromise its quality and promote the formation of harmful cholesterol oxidation products (COPs). As demand for healthier food products grows and interest in bio-based additives increases, this study investigated the effects of incorporating biquinho pepper (BP) at 3.0, 3.5, and 4.0% into mayonnaise samples stored under refrigeration at 4 °C for 60 days. For this purpose, we analyzed samples on days 0, 15, 30, 45, and 60 to evaluate BP's potential to reduce cholesterol oxidation. Cholesterol and COPs were simultaneously extracted by direct saponification. Their identification and quantification were performed by HPLC-MS-PDA (Shimadzu LCMS-2020, Tokyo, Japan), equipped with an autoinjector (SIL-10AF), a PDA detector (SPD-M20A), and a Hypersil cyano column (250 mm × 4.6 mm; Thermo Scientific, USA). On day 0, the cholesterol levels ranged from 131.30 ± 1.20 to 134.84 ± 0.50 mg/100 g (dry weight) (p > 0.05). However, from day 15 onward, a decrease in cholesterol contents was observed in all samples. In the control sample, the cholesterol level reduced to 105.40 ± 3.50 mg/100 g on day 60, representing a reduction of 21% compared to day 0 (p ≤ 0.05). In contrast, a lower degradation was determined for the samples containing BP, which showed cholesterol levels ranging from 112.10 ± 1.40 to 117.40 ± 1.30 mg/100 g. The highest protection was observed with 4.0% BP, corresponding to a lower degradation of 4.94%. Additionally, the following cholesterol oxides were identified: 5,6β-epoxycholesterol, 5,6α-epoxycholesterol, 7-ketocholesterol, 7α-hydroxycholesterol, and 7β-hydroxycholesterol. After 60 days of storage, the total COPs contents in the control sample increased significantly to 11.48 ± 0.40 μg/g, nearly three times higher than the initial value on day 0 (4.64 ± 0.01 μg/g), indicating ongoing oxidative degradation during refrigerated storage. The lowest total COPs levels were measured in samples containing BP (from 8.30 ± 0.20 to 9.87 ± 0.70 μg/g) compared to the control (11.48 ± 0.40 μg/g) (p ≤ 0.05). While the control sample showed a 2.5-fold increase in total COPs over 60 days, formulation with 4.0% BP increased by 1.8-fold. Therefore, the overall results indicate that biquinho pepper is a promising natural antioxidant and alternative for preserving the safety and nutritional quality of mayonnaise during refrigerated storage.

Funding agencies: CNPq and CAPES.