Impact of cut to crush delay and bio-chemical changes in sugarcane

Abstract

In the present era of economic liberalization, sugar has become an important commodity for human consumption as well as trade. The global importance of this versatile sweetner could be judged by the fact that its consumption is expected to go much high upto 2020 AD as compared to the present level. Sugarcane plant, once detached from ground loses its machinery to synthesize sucrose. Thus a well ripened harvested crop may lose its sugar within a few days, which tends to increase further due to high ambient temperature. These loses tend to increase during processing, especially in those units where hygienic conditions are rather unsatisfactory. The post harvest sugar lose is one of the most vexing problems of sugar industry and has attracted widespread attention in the recent years. A study was carried out to examine the effect of staling h on three early and three mid-late maturing varieties in view of biochemical changes occurred in staled cane juice from 0 h - 96 h. The ambient temperature ranged around 40- 420C. TSS, sucrose, purity coefficient, dextran, proteins, free amino acid contents, acid and neutral invertases were assayed. The sucrose content rapidly deteriorated after 24 h staling. The invert sugar and dextran content increased rapidly after 48 h. free amino acid contents increased rapidly up to 72 h. Free amino acid contents were higher in early group of varieties than mid-late group of varieties. Findings indicated that both the group of varieties fastly deteriorated sucrose content after 24 h. Higher dextran formation was observed after 48 h in most of the early varieties due to higher concentration of sucrose thereby TSS increased during staling periods. It may be inferred that the early maturing varieties should be crushed within 24 h and mid-late maturing varieties within 48 h after harvest under high ambient temperature. Mid-late maturing varieties showed lower values of dextran, free amino acid content, protein and invertase activities. Therefore, these varieties were found capable in retaining quality characters up to longer durations after harvest. It has also been observed that mid-late varieties having lower sucrose content than early varieties deteriorated less during staling. In the cane juice of early maturing varieties, where sucrose and brix values were higher than mid-late, produced relatively higher invertase activities, dextran, free amino acid content and proteins in the late staling h possibly due to higher microbial infestation.