Effect of Pouch Size on Sterilization of Ready-To-Eat (RTE) Bracken Ferns: Numerical Simulation and Texture Evaluation

Bracken fern (Pteridium aquilium, BF) is a widely consumed vegetable. It has the potential to be manufactured as a ready-to-eat (RTE) product as a cooking ingredient and a side dish. The aim of the current study was to develop sterilized BF RTE products and to investigate textural qualities depending on the size of the pouches. The F0-value at the cold point according to pouch size (100, 150, and 200 g) targeted at 15 min was determined through heat transfer simulation using the calibrated heat transfer coefficient. The location of the cold points in the stand-up pouches was moved upward from the bottom of the pouch by increasing the pouch size. The sterilization time for 100, 150, and 200 g was evaluated as 35.0, 41.5, and 47.5 min, respectively. The textural properties measured using the cutting test showed significant differences according to the location in the pouch. The textural degradation of BF in the top part of the pouch was more extensive than that at the bottom due to the smaller dimensions. In addition, the percentage of textural degradation in the top part increased with increasing pouch sizes. The methods introduced in this study can be applied to validate the degree of sterilization and the texture of various stalk vegetables used for ready-to-eat products packed in stand-up pouches.