In this study ultrasound assisted extraction (UAE) of polysaccharides from hazelnut skin has been studied. Optimum sonication time has been evaluated depending on responses such as amount of carbohydrate and dried sample and thermogravimetric analysis. Chemical and structural properties of extracted material have been determined by Fourier transform spectroscopy attenuated-total reflectance (FTIR-ATR) spectroscopy. Pretreated hazelnut skin powders were extracted in distilled water. Mixture was sonicated by ultrasonic processor probe for 15, 30, 45, 60, 90, and 120 min. The results of UAE showed that maximum ethanol insoluble extracts in 60 min and the highest dry matter content could be obtained in 120 min extraction. Although total carbohydrate content of ethanol insoluble dry extract decreased with time, total carbohydrate in ethanol soluble fraction increased. Polysaccharides extracted from hazelnut skin were assumed to be pectic polysaccharide according to the literature survey of FTIR analysis result. Application time of UAE has an important effect on extraction of polysaccharide from hazelnut skin. This affect could be summarized by enhancing extraction yield up to critical level. Decrease of the yield in ethanol insoluble part could be explained by polymer decomposition. Most suitable model was hyperbolic model by having the lowest root mean square error and the highest R² values.

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.