Anthocyanin composition and storage degradation kinetics of anthocyanins‐based natural food colourant from purple‐fleshed sweet potato

Abstract

A natural colourant derived from purple-fleshed sweet potato (PFSP) by ultrasound-assisted solvent extraction was examined in terms of its anthocyanins and 6-month storage stability under different conditions: avoid from light at 25 (AL25) and 37°C (AL37) and under fluorescent light at 25°C (FL25). This PFSP colourant mainly contained the following peonidin anthocyanins: peonidin 3-p-hydroxybenzoyl sophoroside-5-glucoside, peonidin 3-feruloyl sophoroside-5-glucoside, peonidin 3-caffeoyl sophoroside-5glucoside, peonidin dicaffeoyl sophoroside-5-glucoside, peonidin 3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside and peonidin caffeoyl-feruloyl sophoroside-5-glucoside. The degradation ratios of PFSP anthocyanins (PFSPAs) under AL25, AL37 and FL25 were around 50.7%, 89.0% and 87.0% respectively. The FL25 and AL37 conditions had similar effects on the colourant's total colour change (DEab). The degradation kinetics followed the zero-order reaction models. The PFSPAs were more stable during storage than other anthocyanins because they mainly consist of di-acylated and double glycosylated forms of peonidin derivatives. These results may promote the application of PFSPAs as a novel natural colourant in food industry.According to He et al. (2016), UPLC-QTOF-MS analysis was performed using an ACQUITY UPLC instrument equipped with a PDA detector and a SYNAPT

Optimization Ultrasound-Assisted Deep Eutectic Solvent Extraction of Anthocyanins from Raspberry Using Response Surface Methodology Coupled with Genetic Algorithm

“…Initially, the reason might be due to the elevated temperature, which could improve the solubility of anthocyanins in the extraction solvent and accelerate the mass transfer of intracellular anthocyanins [ 36 ]. However, a high temperature might cause the degradation of anthocyanins because of their thermal susceptibility [ 37 ]. Similar experimental results were obtained by other authors in the case of anthocyanins from Hibiscus sabdariffa calyces for natural food colorants and Aronia melanocarpa skin waste by using different temperatures [ 38 , 39 ].…”

Influence of particle size distribution on nutritional composition, microstructural and antioxidant properties of orange and purple‐fleshed sweet potato flour

“…In China, the most popular varieties of sweet potato are purple and orange‐fleshed due to their excellent color and nutritional characteristics. Orange‐fleshed sweet potato rich in carotenoids that show strong antioxidant capacities due to conjugated double bonds (Azeem et al., 2020; Kourouma et al., 2020; Mordi et al., 2020), while purple‐fleshed sweet potato possesses an abundant amount of phenolics compounds as compared to other colored ones (Meng et al., 2019; Wang et al., 2018), in which anthocyanins are more stable than those from other plants (Quan et al., 2019), showing the immense potential of free radical scavenging, anti‐inflammatory, and anticarcinogenic activities (Salehi et al., 2020).…”

Grown to be Blue—Antioxidant Properties and Health Effects of Colored Vegetables. Part I: Root Vegetables

“…Processing and storage conditions are important for the chemical composition and the visual quality of sweet-potato tubers, with heating treatments and higher pH having a detrimental effect on anthocyanins and starch content and on flesh color [139,[169][170][171][172]. Pretreatments such as blanching, osmotic dehydration, ultrasound-assisted dehydration, and ultrasound-assisted osmotic dehydration before microwave drying also had an impact on total phenolic and anthocyanin content of orange-and purple-fleshed sweet-potato slices [173].…”