Heat treatment, sodium carbonate, ascorbic acid and rosemary essential oil application for the preservation of fresh Rosmarinus officinalis quality

Abstract

As the need for healthy and nutritional food rises, the use of medicinal and aromatic plants (fresh herbs) also increases due to the health benefits that they possess. However, these products are highly perishable and their shelf life might be limited, depending on the product. The aim of the present study was to examine the effectiveness of heat treatment (HT 40 °C, HT 55 °C), sodium carbonate (SC 1%, SC 3%), ascorbic acid (AA 1%, AA 2%) and rosemary essential oil (EO 1:1500, EO 1:500) on fresh rosemary bundles quality attributes during storage at 4 °C for 12 days. The results showed that the application of AA (1%, 2%) increased the respiration rate of rosemary, whilst all treatments (except HT 40 °C, HT 55 °C) increased the antioxidant activity (assayed by DPPH, FRAP and ABTS methods). Moreover, HT 40 °C, SC (1%, 3%) and AA (1%, 2%) decreased the microbial load (filamentous fungi). Regarding sensory attributes, the use of AA and rosemary EO were able to preserve the aroma and green color of rosemary, whilst the application of SC and HT resulted in a less acceptable/marketable product. The findings of this study exhibit that the examined treatments might be used as alternative means for fresh herbs preservation/ enhancement of quality attributes.