Lamb meat burgers shelf life: effect of the addition of different forms of rosemary (Rosmarinus Officinalis L.)

The effect of different rosemary formats (powdered: RP; extract: REX; essential oil: REO; oleoresin: ROL) on vacuum-packed lamb meat raw burgers shelf-life was studied. pH, colour coordinates (L*, a*, b*), microbial count (Total viable count, Enterobacteriaceae, Pseudomonas spp., Lactic acid bacteria), and lipid oxidation were analysed during 14 d. A control group, without spice was used. pH decreased (p < .001) in all samples, reaching the lowest values in ROL. L* remained stable, except in ROL (p < .05), a* showed variations in RP (p < .05), and b* in RP (p < .01) and in ROL (p < .001). Differences (p < .001) were found among treatments on lipid oxidation, with the lowest values in RP. The microbial counts increased with the storage (p < .001) in all microorganism groups in all batches. Shelf life was 10 days for RP and control, 14 days for REX, REO and ROL.

Automated summary

The study found that rosemary powder had the best effect on extending the shelf life of vacuum-packed lamb meat raw burgers, while oleoresin had the worst effect. With the increase in storage time, microbial counts continued to increase in all batches.