Preservation Potential of Fenugreek Seed and Leaf Extracts in Mayonnaise: Impact on Antioxidant Activity, Peroxide Value, and Sensory Quality

Fenugreek extracts have remarkable antioxidant properties and can be used as natural preservatives for products containing a large amount of oil, such as mayonnaise. In this study, mayonnaise was enriched with phenolic extracts of fenugreek seeds (FSE) and fenugreek leaves (FLE), and the quality attributes of the enriched mayonnaises were investigated during storage. FSE and FLE were added to mayonnaise at three different levels (0.05, 0.10, and 0.20%), and the samples were stored at 4°C for 12 weeks and at 25°C for 6 weeks. Antioxidant activity, peroxide value, titratable acidity, color change, and microbial and sensory analysis were performed. As a result, enrichment of mayonnaise with FSE and FLE improved its quality properties during storage. The antioxidant activities of the added FSE and FLE samples were preserved ∼87% and ∼47% at 4°C, and 81% and ∼27% at 25°C, respectively. Furthermore, the increase in the peroxide values of the enriched mayonnaise with extracts during storage was less than that of the added synthetic antioxidant (EDTA) samples. The highest total color change (ΔE) was observed for FLE-added samples for all levels of addition. Multifactorial ANOVA showed significant effects (p < 0.05) of type and concentration of additives, storage time, and their interactions on antioxidant activity, peroxide value, titratable acidity, and color change at both storage temperatures (4°C and 25°C). R² and adj-R² values indicated highly accurate models for all parameters. The addition of FLE and FSE at the highest level (0.20%) prevented the growth of total aerobic mesophilic bacteria by 2.1 and 3.2 logs and the growth of total yeast/mold by 1.0 and 1.3 logs at 25°C, respectively. Sensory attributes (color, odor, taste, texture, and general acceptance) of the mayonnaises added to FSE and FLE had higher scores than the control sample at the end of storage.