The effect of nano/microparticles of bee pollen on the shelf life of high-fat cooked sausage during refrigerated storage

Abstract

Sausage is susceptible to oxidative changes in lipids and microbial spoilage due to the presence of water, fat, protein, and vitamins. Bee pollen (BP) as a source of potential antioxidants and antibacterial compounds can effectively prevent lipid peroxidation and microbial spoilage in meat products. The aim of the present study was to investigate the antibacterial and antioxidant activities of BP and the effects of nano/microparticles of bee pollen extract (n/m BP) at a concentration of 125 and 250 mg/100 g meat on the oxidative stability and microbial growth of high-fat sausage during 30 days of storage at 4°C. The formation of BP particles in the nano/micro range was confirmed by scanning electron microscopy. High concentrations of total phenolic compounds (28.26 ± 0.10 mg GAE/g BP) with antioxidant activity (EC₅₀ = 5.4 ± 0.07 mg/mL) were detected in BP. Based on the microdilution assay, the minimum inhibitory concentration of n/m BP for all test bacteria was 1000 (μg/mL) and the minimum bactericidal concentration of n/m BP was 2000 (μg/mL) for Staphylococcus aureus and Bacillus cereus and 4000 (μg/mL) for Escherichia coli and Pseudomonas aeruginosa. The n/m BP treatment (250 mg/100 g meat) showed a higher pH value (p < .05) and lower TBARS values (p < .05) than the ascorbic acid treatment (100 mg/100 g meat) and the control during the storage period. The microbial analysis showed that the addition of n/m BP led to a significant decrease (p < .05) in the total bacterial count, coliforms, S. aureus, and fungal population compared to the other samples. The results show that the addition of n/m BP (125 mg/100 g) can improve the texture, taste, and overall acceptability of the sausage compared to the control sample. In conclusion, this study suggests that BP can replace synthetic antioxidants in high-fat sausages at the nano/microparticle level.

Keywords: antimicrobial; antioxidant; bee pollen; sausage.

FIGURE 1

SEM images of n/m BP prepared at 1600× magnification (a), 15,000 × magnification (b), 4163 × magnification (c), and 16,000 × magnification (d).

FIGURE 2

Effect of n/m BP on the DW% in sausage samples. Vertical bars represent the standard deviation (n = 3). Different letters indicate statistically significant differences (p < .05).

FIGURE 3

Effect of n/m BP on the pH in sausage samples. Vertical bars represent the standard deviation (n = 3). Different letters indicate statistically significant differences (p < .05).

FIGURE 4

Effect of n/m BP on TBARS in sausage samples. Vertical bars represent the standard deviation (n = 3). Different letters indicate statistically significant differences (p < .05).

FIGURE 5

Effect of n/m BP on the microbial growth in sausage samples during 30 days of storage. Vertical bars represent the standard deviation (n = 3). Different letters indicate statistically significant differences (p < .05); (A) S. aureus; (B) Coliform; (C) Fungi; (D) total bacterial count. C, control; T1, Sausage with n/m BP (125 mg/100 g meat); T2, Sausage with n/m BP (250 mg/100 g meat); T3, Sausage with ascorbic acid (100 mg/100 g meat).

FIGURE 6

Consumer acceptability scores on a 5‐point scale for sausage samples in the third day. C, control; T1, Sausage with n/m BP (125 mg/100 g meat); T2, Sausage with n/m BP (250 mg/100 g meat); T3, Sausage with ascorbic acid (100 mg/100 g meat).