Maillard reaction products-based encapsulant system formed between chitosan and corn syrup solids: Influence of solution pH on formation kinetic and antioxidant activity.

Maillard reaction products (MRPs) between chitosan and various sugars with enhanced antioxidant activity were previously produced. However, few reports address the chitosan and corn syrup solids system that has been successfully used to encapsulate nutraceutical oils. Maillard reaction is pH-responsive, the influence of solution pH on the formation kinetic and antioxidant activity of MRPs was therefore evaluated in this work. FT-IR and zeta-potential results confirmed the formation of MRPs between chitosan and corn syrup solids. Possible Amadori compounds signals were observed clearly in the 1H NMR spectrum. Brown color development depended on initial solution pH, following a zero-order kinetic regression. Antioxidant activity of reaction products was higher than the native system and increased with an increase in the initial pH of the solution. Developed MRPs with a dual function as antioxidant and encapsulant can possibly be used to protect emulsified oil from oxidation.

Effect of microwave drying on quality kinetics of okra.

The effects of microwave drying on quality attribute of okra were evaluated. Microwave power values show significant effect on moisture diffusivity, color, hardness and sensory attributes of dried okra. The total color change ([Formula: see text]) increased whereas [Formula: see text], [Formula: see text] and [Formula: see text] decreased with an increase in both power and time. The kinetics of [Formula: see text] and [Formula: see text] were well expressed by zero-order kinetic models, while [Formula: see text] and [Formula: see text] followed first-order kinetic models. Hardness was expressed by a first-order kinetic model. Sensory evaluation showed that okra dried at 800 W was most attractive in terms of color, texture, flavor and overall liking. Microwave drying at 800 W presented the shortest drying time with the least change in hardness, but the most change in color. Thus, high-power microwave drying potentially produces dried fruits and vegetables with minimum changes in hardness.

Use of average molecular weights for product categories to predict freezing characteristics of foods.

In the design of food freezing process, food property parameters, initial freezing temperature (T(Fi)), and frozen water fraction (X(I)) are required. The predictive approaches of these 2 parameters have been developed based on mass fractions and molecular weights of specific food components such as proteins, carbohydrates, minerals, and acids/bases. In this study, the molecular weights of the key mineral and acid/base components were successfully represented using average molecular weights (M) and 4 T(Fi) and X(I) calculation approaches were proposed. Based on an analysis of 212 food products, the absolute differences (AD) between the experimental and predicted T(Fi) values for the 4 approaches were small. The prediction for the food model category was excellent with average AD values as low as +/- 0.03 degrees C. For the other food categories, the prediction efficiency was impressive with values between +/- 0.22 and +/- 0.38 degrees C. The predicted relationship between temperature and X(I) for all analyzed food products provided close agreements with experimental data.