Anthocyanin, phenolics and antioxidant activity changes in purple waxy corn as affected by traditional cooking

• Published in: Food chemistry 2014-12, Vol.164, p.510-517
• Main Authors: Harakotr, Bhornchai, Suriharn, Bhalang, Tangwongchai, Ratchada, Scott, Marvin Paul, Lertrat, Kamol
• Format: Article
• Language: English
• Subjects: Anthocyanins - analysis; Antioxidant capacity; Antioxidants - analysis; Bioactive compounds; Biological and medical sciences; Cooking; Domestic cooking; Food toxicology; Medical sciences; Phenols - analysis; Purple waxy maize; Toxicology; Zea mays - chemistry
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2014.05.069

•Thermal cooking caused decreases in antioxidant compounds and activity on cooked corn.•Steam cooking preserved more antioxidant compounds than boiling.•Separation of kernels from the cob prior to cooking caused increased loss of antioxidant compounds.•Boiling caused a significant loss of antioxidant compounds into the cooking water.•Boiling water was a source of purple pigment and may be a valuable cooking co-product. Antioxidant components, including anthocyanins and phenolic compounds, antioxidant activity, and their changes during traditional cooking of fresh purple waxy corn were investigated. As compared to the raw corn, thermal treatment caused significant (p⩽0.05) decreases in each antioxidant compound and antioxidant activity. Steam cooking preserved more antioxidant compounds than boiling. Boiling caused a significant loss of anthocyanin and phenolic compounds into the cooking water. This cooking water is a valuable co-product because it is a good source of purple pigment. By comparing levels of antioxidant compounds in raw and cooked corn, we determined that degradation results in greater loss than leaching or diffusion into cooking water. Additionally, separation of kernels from the cob prior to cooking caused increased loss of antioxidant compounds.