Shirazi balangu (Lallemantia royleana) seed mucilage: Chemical composition, molecular weight, biological activity and its evaluation as edible coating on beefs

In this study, Lallemantia royleana seed mucilage (LRSM) was extracted from whole seeds using hot-water extraction. The structural information (monosaccharide compositions and molecular weight analysis), chemical composition (moisture, protein, ash, fat and carbohydrate), biological activity (antimicrobial, total phenol content and antioxidant activity) and effect LRSM edible coating on population of microbial pathogens (total viable count (TVC), psychrotrophic bacteria, Escherichia coli, Staphylococcus aureus and fungi), chemical changes (thiobarbituric acid, peroxide value and pH) and sensory attributes (color, odor and total acceptability) of the beef slices at 4 C for 18 days (0, 3, 6, 9, 12, 15 and 18) were determined. The LRSM had 76.74% carbohydrate, 3.86% protein, 9,92% ash and 9.48% moisture. LRSM is a high molecular weight (1.19 x 10(6) Da) polysaccharide, composed of galactose (36.28%), arabinose (35.96%), rhamnose (15.18%), xylose (7.38%) and glucose (5.20%). The LRSM total phenolic content and antioxidant activity (IC50) were equal to 82.56 +/- 1.6 mu g GAE/mg and 528.54 0.35 mu g/ml, respectively. The results showed that, the beef shelf life based on TVC for samples control, LRSM, LRSM + 1% AHEO, LRSM + 1.5% AHEO, and LRSM + 2% AHEO were 6, 9, 9, 12, and 15 days, respectively. There was no significant difference between LRSM + 1% AHEO and LRSM samples, but the TVC in first one had slight changes than LRSM. Compared to the control samples, LRSM extended the microbial shelf life, oxidative stability and sensorial acceptability of beef by 3, 6 and 6 days, respectively. (C) 2018 Published by Elsevier B.V.