Extraction, characterization, and rheology of Opuntia ficus indica cladode polysaccharides

In this study, hot water extraction was applied to obtain water-soluble pectin of Opuntia ficus indica (OFI) cladode. The yield was found 0.18–0.06% in fresh-weight with the degree of esterification at 48 ± 1.25% expressing that extracted polysaccharide has low-methoxyl (LM) pectin features. Some properties of OFI cladode pectin and commercial LM pectin were investigated. Infrared spectrums of the samples were found mostly similar by having major pectin constituents. 0.25, 0.5, 1, 2 and 3% w/v solutions were prepared for rheological properties at 25, 30, 35 and 40°C. Solutions prepared both using commercial pectin (CP) and OCP represented Newtonian behavior at applied shear rate region. More than 1% w/v concentration, CP showed higher thickening property compared to OCP solutions at various temperatures where CP samples were heavier compared to OCP. The activation energy of OCP solutions was higher than CP meaning that CP had stronger interaction between molecules by representing better stability. Novelty impact statement Opuntia ficus indica (OFI) is well known as the fruit part, however, the cladode part has a great potential for food use as a polysaccharide source. Cladode is rich in water-soluble pectic polysaccharides and there is no commercial cladode pectin available on the market. OFI cladode can be used as a cheap source of low-methoxyl pectin with some modifications due to the application area.