Chemical and Microbial Changes in Dehulled Confectionery Sunflower Kernels during Storage Under Controlled Conditions

Publisher Website
Google Scholar
Abstract
Samples of freshly dehulled, confectionery sunflower kernels were adjusted to moistures of 5.2, 10.5, and 14.7%, sealed in plastic bags and stored at 35, 75, and 95 F (1.7, 23.9, and 35 C) for 12 weeks. At 2-week intervals aliquots were removed for flavor, chemical, and microbiological analyses. Acid values of oil extracted from stored kernels increased with temperature, moisture content, and storage time. At acid values of 4 or higher, kernels had a sour flavor. In general, the peroxide value decreased with increased moisture at each temperature and storage period. The initial aerobic plate count of the sunflower kernels was log 6.83/g, the Enterobacteriaceae count was log 6.15/g, and the yeast and mold count was log 3.65/g. From countable plates randomly selected, about 80% of the Enterobacteriaceae were identified as Enterobacter agglomerans (Erwinia herbicola). At 35 F microbial counts generally changed little. At 75 F, however, counts decreased rapidly; and at 95 F, yeast and mold counts of 14.7% moisture kernels increased, Enterobacteriaceae counts decreased, and aerobic plate counts decreased except in high moisture samples. A microbiological survey of whole sunflower seed and dehulled kernels from three dehulling operations indicated that contamination of the dehulled kernels was primarily from sunflower hulls rather than from processing equipment.

This publication has 0 references indexed in Scilit: