ABSTRACT
To clarify the most suitable fish paste for preparing lion's head meatballs, this study investigated the effect of adding 6 different silver carp fish pastes: fresh unwashed (group 1-1), fresh washed (group 1-2), frozen unwashed without antifreeze agent (group 2-1), frozen washed without antifreeze agent (group 2-2), frozen unwashed with antifreeze agent (group 3-1), and frozen washed with antifreeze agent (group 3-2) on the basic nutrients, color, texture properties, waterholding capacity, sensory and flavor properties, thiobarbituric acid reactive substance (TBARs) value, and total volatile basic nitrogen (TVB-N) content of pork/fish composite meatballs. The results showed that the contents of protein and fat in meatballs from groups 2-1 and 2-2 were lower than those in groups 3-1 and 3-2, and the contents of water, protein and fat were 61.68%, 11.32% and 19.41% for group 2-1, and 62.45%, 11.09% and 19.33% for group 2-2, respectively. The gel properties, hardness, elasticity, cohesion, and sensory quality of groups 3-1 and 3-2 were significantly higher than those of groups 2-1 and 2-2 (P < 0.05), but there was no significant difference compared with groups 1-1 and 1-2. The odor response value of groups 3 was lower than that of groups 1, and groups 3 had the highest sweetness value (3 039.66) and lowest bitterness value (534.59). The TBARs value and TVB-N content in groups 1-2, 2-2, and 3-2 (with washed fish paste) were significantly lower than those in groups 1-1, 2-1 and 3-1 (with unwashed fish paste) (P < 0.05). Since fresh fish paste is not easy to store and subject to spoilage, frozen washed fish paste with antifreeze agent can be used to produce composite meatballs.
ABSTRACT
The open carrier system (OC) is used for vitrification due to its high efficiency in preserving female fertility, but concerns remain that it bears possible risks of cross-contamination. Closed carrier systems (CC) could be an alternative to the OC to increase safety. However, the viability and developmental competence of vitrified/warmed (VW) oocytes using the CC were significantly lower than with OC. We aimed to improve the efficiency of the CC. Metaphase II oocytes were collected from mice after superovulation and subjected to in vitro fertilization after vitrification/warming. Increasing the cooling/warming rate and exposure time to cryoprotectants as key parameters for the CC effectively improved the survival rate and developmental competence of VW oocytes. When all the conditions that improved the outcomes were applied to the conventional CC, hereafter named the modified vitrification/warming procedure using CC (mVW-CC), the viability and developmental competence of VW oocytes were significantly improved as compared to those of VW oocytes in the CC. Furthermore, mVW-CC increased the spindle normality of VW oocytes, as well as the cell number of blastocysts developed from VW oocytes. Collectively, our mVW-CC optimized for mouse oocytes can be utilized for humans without concerns regarding possible cross-contamination during vitrification in the future.