For Freezer B, the average temperature was _25 ฑ 1 _C ranging from _16 _C to _29 _C. According to Anderson et al. (2004) who studied five different models of household refrigerators, the models with quick freeze function dropped the temperature more quickly
In Fig. 1, the temperature profiles of Freezer A and Freezer B during the sample trials are presented, as well as the cooling curves of the fish burger obtained in both freezers. Freezer A
(Tavg = _15 ฑ 0 _C) follows a sinusoidal variation, as temperature control in domestic refrigerators and freezers are usually operated by a simple on/off actuation controller. On the other hand, Freezer
B (Tavg = _25 ฑ 1 _C) was used with the quick-freeze capability and the quick temperature drop is shown in Fig. 1. Anderson et al. (2004) obtained similar temperature profiles for household refrigerators. Likewise, quick-freeze models had a quick temperature drop and remained at lower temperatures and models with no quick-freeze function showed the sinusoidal behavior. Both time–temperature curves
(Fig. 1) of fish burgers showed the typical slow freezing curve with a temperature plateau around 0 to _5 _C (Rahman and Driscoll, 1994; Rahman et al., 2009). The product remained in a longer temperature plateau around 0 to _5 _C (120 ฑ 5 min) in Freezer A than Freezer B (61 ฑ 5 min). As previously discussed, the temperature range from 0 to _5 _C is considered as a critical zone that determines both the number