Compensating for temperature drops in still retorts [Canned foods processing]

Heat penetration measurements were done on 303 × 406 and 603 × 700 cans of whole kernel corn in brine in a still retort with intentional deviations in retort temperature. Based on the magnitude and duration of the deviation, supplemental time at the scheduled process temperature was added to the process according to published correction procedures. In all cases (six points from the correction procedure were evaluated), the least F values for the corrected processes were equal to or greater than the least F values for the corresponding scheduled process without deviation. On 303 × 406 cans with a retort temperature of 121.1°C, the least F values for the corrected processes ranged from 15.1 to 18.8, compared with 14.7 for the 26-L process. On 303 × 406 cans with a retort temperature of 115.6°C, the least F values for the corrected processes ranged from 10.9 to 12.3, compared with 10.8 for the 26-L process. Accordingly, the published correction procedures were satisfactory to compensate for temperature drops in still retorts for the convention heating product used in this study.