2.1. Preparation of the Raw Materials

Mackerel (S. japonicus) samples were obtained from EBADA Fishery Co. Ltd., Busan, Korea, under frozen conditions. Fresh radish samples (Raphanus sativus) were purchased from a local market in Busan, Korea. Frozen mackerel samples were placed in zip-lock plastic bags and thawed using three different methods: air thawing (AT, 18–20 °C), water thawing (WT, 22–24 °C), and high-frequency defroster (HFD; TEMPERTRON FRT-10, Yamamoto Vinita Co. Ltd., Osaka, Japan). The temperature gap between the HFD (internal) and room temperature was within 3 °C. The weights of mackerel samples before and after the thawing process were measured to evaluate their drip loss percentage.