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This study was designed within the scope of industrial exploitation of antioxidant extracts from Hibiscus sabdariffa. Efficiency in the extraction of antioxidants (total phenolics, flavonoids and anthocyanins) from calyces was assessed through different processes involving solvents (water, 80% acetone and 80% methanol), microwaves and ultrasounds. Results indicated that microwave extraction with 80% acetone gave the highest yield for total phenolics, expressed as gallic acid equivalents (GAE) per g dry weight (DW) (3.73 GAE/100 g DW), while the highest results for total flavonoids and anthocyanins were found in the microwaved aqueous extracts. Antioxidant activity of the extracts reported the highest reducing power for aqueous extracts with microwave extraction, while 80% acetone and methanol samples exhibited the highest antioxidant activity by high-performance thin-layer chromatography (HPTLC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) reagent. HPTLC performed for screening of phenolic compounds revealed the occurrence of anthocyanins in dimer-like bands. Laboratory tests showed high protection against lipid oxidation of the whey spread emulsion (22.32 h) incorporated with the sonicated aqueous extract. Results of peptide sequencing data by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), after sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis, revealed protein–polyphenols interactions by the formation of dimers between polyphenols and protein/peptides. These interactions were found without effect on the oxidative stability of the emulsions. These study suggest that H. sabdariffa’s calyces have the potential to be used like food antioxidants.

Interesterification becomes a very powerful tool in food industry. A blend of coconut oil and palm stearin is enzymatically interesterified by lipase (EC 3.1.1.3) in an aquarium reactor. The interesterified blend obtained is then incorporated in madeleines, mini croissants, and mini rolls. Physicochemical parameters’ assessment for molasses used is in good agreement with the international standards. Fatty acid composition of the interesterified blend and sugar content of molasses were assessed by gas chromatography (GC) and high performance liquid chromatography (HPLC). A sensory evaluation of the madeleines, mini croissants, and buns has been carried out by untrained tasters, with a statistical analysis by a principal component analysis (PCA). Chromatographic characterization by Gas Chromatography revealed fatty acids, ranging from C6: 0 to C22: 0. Liquid sugar’s content by high performance liquid chromatography revealed three main sugars: sucrose, glucose, and fructose. Results of the sensory analysis showed the good quality of the prepared products.