Thermal, structural, morphological and bioactive characterization of acid and neutral modified loquat (Eriobotrya japonica lindl.) seed starch and its by-products

• Published in: Journal of thermal analysis and calorimetry Vol. 147; no. 12; pp. 6721 - 6737
• Main Authors: Costa, Bruno Patrício, Carpiné, Daniele, da Silva Bambirra Alves, Fillemon Edillyn, Barbi, Rafaela Cristina Turola, de Melo, Anely Maciel, Ikeda, Mônica, Ribani, Rosemary Hoffmann
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.06.2022; Springer; Springer Nature B.V
• Subjects: Acids; Analytical Chemistry; Antioxidants; Biodegradability; By products; Byproducts; Chemistry; Chemistry and Materials Science; Composition; Differential scanning calorimetry; Industrial applications; Industrial wastes; Inorganic Chemistry; Lipids; Measurement Science and Instrumentation; Morphology; Physical Chemistry; Polymer Sciences; Proteins; Rheological properties; Seeds; Stability analysis; Starches; Steeping; Structural analysis; Thermal stability; Thermogravimetric analysis; Antioxidants; Agro-industrial residues; Acid extraction; By-products; Non-conventional starch; Thermogravimetry
• ISSN: 1388-6150; 1588-2926
• DOI: 10.1007/s10973-021-10965-2

Extraction methods are determinant in technological properties of non-conventional starches. Different steeping procedures are capable of modifying the starch regarding its proximal composition and its morphological thermal and rheological profile, also changing the residues produced during the extractions. Thus, this study aimed to characterize the modified loquat seed starch (LSS) by neutral (NS—neutral starch) and acid (AS—acid starch) steeping and their by-products (AEB—acid extraction by-product) and (NEB—neutral extraction by-product). This study was based on data from thermal analysis, viscosity profile, antioxidant properties and determination of structural and morphological characteristics. Regardless of the extraction method applied, LSS presented a C-type crystalline structure. The AS resulted in a less yellowish starch, with low protein (1.18%), lipid (0.34%) and ash content (0.15%). Compared with the NS, the AS provided more thermal stability. Using differential scanning calorimetry (DSC) and Rapid Visco Analyzer (RVA), was verified a low gelatinization temperature (60.53–60.55 °C) and a higher tendency to gelatinization of the starches. Furthermore, higher antioxidant capacity was observed for NS (600.20 mg GAE/100 g). Moreover, all by-products presented higher content of fiber (65.82%) and protein (8.92%), verified by their proximal composition and Scanning Electron Microscopy. The thermogravimetric analysis showed a low thermal stability for by-products. These findings demonstrate that all samples obtained from loquat seed showed potential characteristics for industrial usage in new processes. Their by-products can also be associated with the decreasing of agro-industrial waste and can be used in food formulations or biodegradable films.