Longer Bread Shelf-Life and Improved Noodle-Making Properties Imparted by a Novel Wheat Genotype Are Stable in Different Genetic Backgrounds.


Inokuma T(1)(2), Vrinten P(1), Shimbata T(1), Sunohara A(1), Fujita M(3), Nakamura K(4), Ishikawa N(5), Takata K(5), Kiribuchi-Otobe C(2)(3), Nakamura T(6).
Author information:
(1)Central Laboratory Innovation Center, Nippn Corporation, 5-1-3 Midorigaoka, Atsugi, Kanagawa 243-0041, Japan.
(2)Faculty of Life and Environmental Science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
(3)Institute of Crop Science, NARO, 2-1-18 Kannondai, Tsukuba, Ibaraki 305-8666, Japan.
(4)Kyusyu Okinawa Agricultural Research Center, NARO, Izumi 496, Chikugo, Fukuoka 833-0041 Japan.
(5)Western Region Agricultural Research Center, NARO, 6-12-1 Nishifukatsu-cho, Fukuyama, Hiroshima 721-8514, Japan.
(6)Tohoku Agricultural Research Center, NARO, 4 Akahira, Shimo-kuriyagawa, Morioka, Iwate 020-0198, Japan.


A recently developed wheat variety, known as 5-5 wheat, which has inactive GBSSI-B1, GBSSI-D1, SSIIa-B1, and SSIIa-D1 isozymes, accumulates a novel type of starch, affecting bread texture and leading to reduction in bread staling. These properties are potentially useful for commercial bakery products; thus, the 5-5 genotype represents a new resource for wheat breeding. In this study, the 5-5 alleles were backcrossed into the hard wheat variety "Minaminokaori" and the soft wheat variety "Shirogane-Komugi", which are both leading Japanese wheat varieties. In comparison to their parental varieties, the two 5-5 near-isogenic lines (NILs) showed a decrease in amylose levels, an increase in the proportion of short chains of amylopectin, a lower gelatinization temperature and enthalpy change, a higher peak viscosity and breakdown viscosity as measured by a Rapid Visco Analyzer, a reduced retrogradation rate, and an increase in grain hardness. Importantly, the 5-5 NILs also showed lower bread crumb firmness and reduced hardening after storage for 2 days at either 20 °C or 7 °C. Considering the results obtained here along with those from the original line, it is clear that the 5-5 genotype can generate specific changes in starch characteristics and staling regardless of its genetic background. Thus, we renamed the 5-5 wheat lines "Slow Staling" (SS) wheat. As expected, our results indicated that the hard wheat SS NIL was more suitable for bread-making. On the other hand, we found that white salted noodle made with the SS NIL of the soft wheat variety had a relatively shorter cooking time, a softer texture, and a reduction in textural changes during storage, all of which are potentially useful for noodle manufacturers.