Evaluation of ball-milling time on the physicochemical and antioxidant properties of persimmon by-products powder

Persimmon by-products are known to contain higher bioactive constituents and biological activities than several other plant by-products. The present study investigated the effect of ball-milling time on the physico-chemical and antioxidant properties of persimmon seed, peel and calyx powders. The by-products were ball-milled using a planetary ball-mill for different periods of time. Increasing ball-milling time from 12 to 24 h improved the specific surface area, solubility, and DPPH radical scavenging activities of all by-products. The variable milling time also did not have any deleterious effect on bioactive constituents, reducing power and iron chelating abilities of seed powder. Ball-milling reduced the water holding capacity of all by-products but did not affect the oil holding capacity. Based on FTIR spectroscopy, increasing milling time did not alter the major constituents of all the by-products. Thus, longer ball-milling time (24 h) at relatively higher rpm (500 rpm) has the potential to produce superfine powders with improved physicochemical and antioxidant activities, thereby adding value to various applications including food. Industrial relevance: Cost effectiveness and eco friendliness are major consideration in the processing of materials. Planetary ball-mill treatment offers an alternative processing method for the utilization of fruit and vegetable industrial wastes. Owing to the nature of some materials, understanding processing time can help in the prediction and regulation of physicochemical, technological and antioxidant properties of materials. (C) 2016 Elsevier Ltd. All rights reserved.