The texture and preference of “mentsuyu (Japanese noodle soup base) caviar” prepared from sodium alginate and calcium lactate

Molecular cooking involves preparing cuisines in a home and/or restaurant kitchen. Spherification is one of the processes of molecular cooking in which sodium alginate and calcium salts are used to produce spherical gels called molecular caviars. In the present study, we used a liquid and seasoned Japanese noodle soup base (mentsuyu) and applied spherification to create mentsuyu caviar (MC). Therefore, the effects of different time course after preparation, gelation times, salt concentrations, and on rupture force and sensory scores in MC were studied. Mentsuyu containing 1% (w/w) sodium alginate was added to 5% (w/w) calcium lactate solution in a drop-by-drop manner using a plastic syringe; the solution immediately gelled to form MC. Rupture forces of MCs exhibited a time-dependent increase after preparation. MCs rupture force after 2.5 min of exposure to calcium lactate was higher than that after 1.5 min of exposure. Moreover, rupture force was higher for MCs made with low-salt (NaCl) mentsuyu than those made with normal salt mentsuyu. In sensory evaluation, MC after 30 min of preparation was stronger than that immediately after preparation. Overall, MC harden over the time after preparation, or with long exposure to calcium lactate, or with low NaCl concentration in foods. The scores for visual appearance and the impact of visual appearance on preference resulting from a combination of MC and Japanese thin wheat noodles (somen) were higher than scores for these properties when combining liquid mentsuyu and somen. Thus, the visual appearance of MC was novel and high-impact compared with liquid mentsuyu. These results suggest that MC is useful for developing novel and high-impact Japanese cuisine (Washoku).