Evaluation of water sorption isotherm, glass transistion temperature, vitamin C and color stability of mango peel powder during storage

• Published in: SN applied sciences 2021-02, Vol.3 (2), p.210, Article 210
• Main Authors: Ferrari, Cristhiane Caroline, Morgano, Marcelo Antonio, Germer, Silvia Pimentel Marconi
• Format: Article
• Language: English
• Subjects: Adsorbed water; Air drying; Antioxidants; Applied and Technical Physics; Ascorbic acid; By products; Chemistry/Food Science; Chemistry: Food Chemistry–Food Technology: Chemistry and Biochemistry of Foods and Food Processing; Color; Contaminants; Controlled conditions; Degradation; Earth Sciences; Engineering; Environment; Equilibrium; Food; Fruits; Glass transition temperature; Humidity; Inorganic contaminants; Isotherms; Low density polyethylenes; Magnesium; Manganese; Mangoes; Materials Science; Mathematical models; Moisture content; Moisture effects; Parameters; Pesticide residues; Pesticides; Phenolic compounds; Phenols; Polyethylene; Polyphenols; Relative humidity; Research Article; Software; Sorption; Stability; Temperature; Transition temperatures; Visual observation; Water activity; Water content
• ISSN: 2523-3963; 2523-3971
• DOI: 10.1007/s42452-021-04251-x

The purpose of this work was to study the physical and chemical stability of the mango peel powder produced by hot-air drying. Sorption isotherms at 25 °C and glass transition temperatures (T g ) of the samples in equilibrium at different a w were determined. The degradation of vitamin C and color parameter b* was evaluated along storage under controlled conditions (relative humidity = 60%, temperature = 10, 25 and 35 °C) during 180 days. GAB model well-described water adsorption of the product, showing a monolayer moisture content (X m ) of 0.1260 g water/g dry solids and a critical a w of 0.56. The Gordon-Taylor model predicted the plasticizing effect of water on glass transition temperature, since T g of the powders kept at different relative humidity conditions decreased as water activity increased. No visual signs of agglomeration and darkening were observed for samples stored at a w  ≤ 0.529. The powders are a source of calcium and rich in potassium, copper, magnesium and manganese. The concentration of inorganic contaminants and pesticide residues were below the maximum allowed limits. The degradation of vitamin C and color parameter b* followed the first and zero-order kinetic models, respectively. The study indicated good stability for the powders along the storage at 10 and 25 °C, which can be incorporated into different food products, showing high retention of vitamin C, phenolic compounds, antioxidant activity and maintenance of color characteristics.