Zein structure and its hidden zearalenone: Effect of zein extraction methods.

• Zein extraction methods affect its structure and zein-zearalenone interaction. • Zein extraction methods can control the conversion of hidden and free zearalenone. • Alkaline method promotes the conversion of hidden zearalenone to free zearalenone. • Acid method promotes the conversion of free zearalenone to hidden zearalenone. Zein, the plant protein, has received great attention in the last years. However, hidden zearalenone (ZEN), the zein-bound ZEN present in zein would have a great hazard to humans and animals. To date, the fates of hidden ZEN under different extraction methods of zein have not been clarified. In this study, the effect of zein extraction methods on conversion of free ZEN with hidden ZEN and its corresponding mechanism were studied. Results showed that the acid extraction condition promoted the formation of hidden ZEN (up to 92.03%), which was closely related to increased hydrophobic cavity of zein. However, alkaline extraction condition caused the conversion of hidden ZEN (from 58.82% to 13.33%) into free ZEN (from 41.18% to 86.67%), which was attributed to the great denaturation of zein. This study is of great significance for controlling hidden ZEN during zein extraction and maize processing. [ABSTRACT FROM AUTHOR]