REDUCTION OF LIQUID WASTE LOADS IN SWEET CORN PROCESSING BY CHANGING SEQUENCE OF UNIT OPERATIONS

Abstract

ABSTRACTMore than 70% of the BOD generated in liquid waste during sweet corn processing reportedly comes from the cutting, washing and blanching operations. The effects of manipulating these operations on BOD and COD were evaluated. Three different sequences were used in combination with both water and steam blanching techniques under pilot plant conditions. Three replications were performed in 1973 and six replications in 1974. The average BOD/COD ratio was 0.56. Steam blanching yielded significantly lower BOD and COD than did water blanching. When corn was first blanched on the cob and then cut and washed, COD was reduced by approximately 50% from the standard cut/wash/blanch sequence. Succulometer values and soluble solids levels in the product were not significantly affected by type of blanch. However, volumes of expressed liquid from succulometer tests were significantly lower for the blanch/cut/wash sequence than for the other two sequences. Blanching on the cob was probably causing gelation of the starches, thus binding water in the kernels.