Okra Extracts as Emulsifiers for Acidic Emulsions

Pectins are widely utilized in the food industry for their gelling, stabilizing and thickening properties. High emulsification capacity is usually attributed to proteins, whereas polysaccharides typically demonstrate negligible surface activity at the o/w interface due to their hydrophilic character; they are therefore not so useful as emulsifying agents. Similarly to most polysaccharides, pectins are not normally considered as emulsifying agents. Okra pectins are found to be acidic, random coil polysaccharides composed of galactose, rhamnose and galacturonic acid. The pectins differ greatly from those extracted from apple, citrus and beet in terms of protein and acetyl contents, indicating their greater hydrophobicity and therefore substantial surface activity at the o/w interface, suggesting that pectin extracts derived from okra can be used as an effective emulsifying agent. The aims of present work were to obtain okra extracts rich in pectins using different extraction protocols and determine their emulsifying capacity in model o/w emulsions under acidic conditions.