Phenolics Extracted from Potato, Sugar Beet, and Sesame Processing By-Products

Abstract

The food-processing industry generates substantial quantities of phenolic-rich by-products that could be valuable natural sources of antioxidants. In this study, the antioxidant properties and total phenolic and flavonoid contents of three industrial by-products (potato peels, sugar beet pulp, and sesame cake) extracted with different solvents were evaluated. Methanol exhibited the highest extraction ability for phenolic compounds, with total phenolics amounting to 2.91, 1.79, and 0.81 mg gallic acid equivalent g −1 dry weight in potato peels, sugar beet pulp, and sesame cake extracts, respectively. Methanolic extracts showed the strongest antioxidant capacity in the two performed assays. The bioactive components extracted with ethanol were further examined for their antioxidant activity in comparison with synthetic antioxidants under accelerated oxidation conditions using sunflower oil as oxidation substrates for 72 h at 70 • C. Inverse relationships were noted between peroxide values and oxidative stabilities and also between secondary oxidation products, measured by p-anisidine value and stabilities at termination of the storage. The high performance liquid chromatography analysis of potato peels, sugar beet pulp, and sesame cake extracts revealed the presence of phenolic compounds. On the basis of the obtained results, potato peels, sugar beet pulp, and sesame cake extracts could serve as natural antioxidants and might be explored to prevent oxidation of vegetable oils. Therefore, they could be used as preservative ingredients in the food and/or pharmaceutical industries.

Optimizing Bioactive Substances Extraction Procedures from Guava, Olive and Potato Processing Wastes and Evaluating their Antioxidant Capacity

“…Whilst, the highest quantities from these components both guava wastes were attained using acetone as illustrated in Table 1 and Figure 1A. These results are agreement with Mohamed, Mohdaly and Jimenez et al [14,20,26]. However, no results established about extraction optimization of these components from guava pomace.…”

“…The OPE had pointed, whilst PPHE had bottomed from their contents of TF and flavonols. These results are in agreement with previous studies of Brahmi and Mohdaly et al [27,28], but are lower than published results by Abaza et al [19]. However, no results found about such components either GPE or OPE as well extraction conditions.…”

“…As for flavones, A 5.0 g 100mL -1 sodium acetate solution were added then mixed well and kept for 2.5 h at room temperature. The absorbance at 440 nm was taken according to Mohdaly et al [20]. The final concentration was expressed as quercetin (Sigma Aldrich, Germany) equivalents (mg QEg Where: Y is the concentration and x is the absorbance.…”

Chemical, Nutritional, Rheological, and Organoleptical Characterizations of Stirred Pumpkin-Yoghurt

“…The TF content of pumpkin-yoghurt samples was determined according to the method of Mohdaly et al [22]. The TF content were expressed as mg quercetin equivalent (QE) per 100 g −1 dw.…”

Antioxidant characteristics of ice cream supplemented with sugarcane (Saccharum officinarum L.) juice

“…In recent years, the role of phenolic compounds in plant based foods has attracted attention due to connections between free radical mediated diseases, lipid peroxidation of LDL, and atherosclerosis (21). Inhibition of free radical mediated diseases via supplementation of foods with natural antioxidants has become an effective therapy for safeguarding the body against chronic diseases (22).…”