Effects of Storage, Prepration and Heat Treatment on WateSoluble Vitamins and Minerals of Sauropus Androgynous

Abstract

Sauropus androgynous is a green leafy vegetable in Vietnam. The proximate main compositions (protein, lipid, ash, and fiber) in leaves were 24.05±0.87, 4.20±0.02, 8.74±0.24, 7.21±1.19% dry weight (DW). This study aimed to determine the change of water-soluble vitamins and minerals of this vegetable plant when stored in polythene bags at a temperature of6.2±2.89oC and moisture 49±13.23% and thermal processing. Throughout the storage period, the sample assessment results by High-Performance Liquid Chromography (HPLC) method revealed that, except for vitamin B3, almost water-soluble vitamins of S. androgynous tend to lose around 50% of their weight after 8 days in the refrigerator. After two days of storage, vitamin B3 increased substantially (123.39±19.45mg/100g DW versus 203.75±3.94 mg/100g DW), then decreased slightly after every two days. The modification of minerals determined by the inductively coupled plasma mass spectrometry IPC-MS method in S. androgynous plant leaves occurred similarly over 8 days of storage. All the plant leaves were boiled in water for 15 min at 90-100oC with two-way pretreatments rub and non-rub the leaves. All analyzed vitamins and minerals have decreased, but no significant differences between samples were treated in two different ways before thermal processing concerning several vitamins and minerals.