Pi F.,Qingdao Technological University |
Pi F.,Jiangnan University |
Pi F.,Collaborative Innovation Center for Food Safety and Quality Control |
Wang J.,Qingdao Technological University |
And 3 more authors.
Thickness-dependent ultrathin films of poly(3-hydroxybutyrate) (PHB) were investigated by using infrared reflection-absorption spectroscopy (IRRAS). It was first found that the autogenetic β-form of PHB could be easily obtained through confining the film thickness under 20 nm at room temperature. Moreover, the interphase of PHB simultaneously exists with the β-form of PHB in the films with a thickness less than 10 nm. With the film thickness increasing from several nanometers to about 30 nm, the PHB molecules gradually carry out an orientation shift at the b-axis of PHB crystallite; simultaneously, for the α-form of PHB a conformational rearrangement probably takes place for the growth of helical crystal unit cells in the ultrathin films. The molecular structures and crystal evolutions at sub-100 nm were explained in detail by analyzing the corresponding IRRAS features. © 2016 Elsevier B.V. Source
Wang L.,Collaborative Innovation Center for Food Safety and Quality Control |
Wang L.,Jiangnan University |
Luo Y.,Collaborative Innovation Center for Food Safety and Quality Control |
Luo Y.,Jiangnan University |
And 10 more authors.
Considering the wide existence of mycotoxin deoxynivalenol (DON) in wheat and derived products, finding ways to detoxify DON in wheat grains as original resources for food-chain contamination is very important to protect human health and reduce economic losses. This study aimed to evaluate the effectiveness of destroying DON in wheat via ozonation under different conditions, such as moisture content (MC), ozone concentration, exposure time, and form of raw-material. The achieved data showed that DON reduction significantly improved with increased ozone concentration and exposure time. The whole wheat flour (WWF) was easier to degrade than the wheat kernels. Higher MC decreased larger amounts of DON. The maximum reduction of DON was 20.10% for the MC group, compared with the 11.79% and 16.29% for the other MC groups. DON concentration decreased from 3.89 mg/kg to 0.83 mg/kg under the generally recognized Maximum Residue Limit (MRL) level of 1 mg/kg, when WWF was treated with 100 mg/L of ozone treatment for 60 min. The first-order kinetic model established in this work showed a good R-squared value (R2 > 0.877) and was consistent with the results. Therefore, ozonation is an effective and rapid way to degrade DON in wheat, especially in whole wheat flour. © 2016 Elsevier Ltd. Source