Extraction, Purification, Optimization, and Application of Galactomannan-Based Edible Coating Formulations for Guava Using Response Surface Methodology

Galactomannan from fenugreek and guar seeds were extracted, purified, and used in edible coatings, optimized via response surface methodology. The results showed that the emulsifying capacity and stability of fenugreek galactomannan (FG) and guar galactomannan (GG) increased with increase in the concentration of galactomannan up to 0.5–1%. The average optimized values of FG and GG in edible coatings were predicted to be 1.71% and 2.11% for weight loss, 0.72% and 2.14% for firmness, 1.02% and 1.44% for TSS, 0.83% and 1.36% for pH, 1.03% and 1.44% for acidity, respectively. Significant decrease in weight loss and maximum retention of firmness was observed in coated guava. The TSS increased up to a certain storage period in all treatments and decreased as the storage period progressed, whereas pH exhibited an increasing trend while a significant decrease in acidity was observed. The findings revealed that the shelf life of guava could considerably be improved by incorporating 1.24% galactomannan from GG and 1.01% from FG in the edible coating.

Effects of sodium alginate edible coating with cinnamon essential oil nanocapsules and Nisin on quality and shelf life of beef slices during refrigeration

The effects of the sodium alginate (SA) coating incorporated with cinnamon essential oil nanocapsules (CEO-NPs) and Nisin, as a new edible coating, were investigated on the preservation of beef slices in the refrigerated storage for 15 days. All beef samples were analyzed for physicochemical properties (pH value, weight loss, the total volatile base nitrogen (TVB-N)) and antimicrobial activity against total bacterial count (TBC). Besides, the changes in color parameters and sensory attributes of all beef samples were evaluated. The results revealed that the incorporation of the complex of CEO-NPs and Nisin retarded the growth of the microorganism and reduced lipid oxidation, as determined by pH, TVB-N, and TBC. This can extend the shelf life of beef slices to 15 days. Moreover, the treatment with the SA coating, incorporating CEO-NPs and Nisin, significantly improved the weight loss, color, odor, textural, and broth attributes of the beef samples. The results suggest that the coating treatment enriched with CEO-NPs and Nisin could significantly inhibit quality deterioration of beef slices, and the complex of CEO-NPs and Nisin can improve antioxidant, antibacterial and sensory properties of the SA coating. Thus, the new edible coating could be regarded as a potential material to preserve beef slices.