In vitro digestibility of cooked noodle products

The in vitro digestive properties of 6 domestic noodle products (spaghetti, somyeon, ramyeon, dangmyeon, naengmyeon, and jjolmyeori) were compared after cooking under the manufacture's recommended cooking conditions. The kinetic constant (k), representing the rate of hydrolysis at the initial digestion stage, was highest in the somyeon noodles (0.1151), followed by naengmyeon (0.0954), and was lowest in the spaghetti (0.0421). However, the concentration of starch (C_∞) hydrolyzed over 2 hr was not different between the spaghetti (96.22) and the somyeon (96.40), indicating that different digestion behaviors occurred in each type of noodle, even though the amounts of digested starch were similar. The ramyeon, dangmyeon, and naengmyeon noodles showed relatively lower C_∞ values than the spaghetti and the somyeon noodles. The spaghetti had the highest amount of slowly digestible starch (SDS, 43%) and the lowest glycemic index (GI, 87.8), whereas the somyeon had the lowest SDS value (9.6%) and the highest GI (93.0). The digestibility differences among the noodles were attributed to differences in their flour compositions and manufacturing processes.