JIA-2019-11

2657 Ji-Eun Kim et al. Journal of Integrative Agriculture 2019, 18(11): 2652–2663 SRC (WSRC), 69.9–82.7 in sucrose SRC (SucSRC), 93.6–157.2 in lactic acid SRC (LASRC), and 96.1–119.9 in sodium carbonate SRC (SCSRC) (Table 1). WSRC value of Korean wheat cultivars carrying Glu-A3c allele (61.8) was higher than that of Korean wheat cultivars with Glu- A3d allele (54.6). Korean wheat cultivars carrying Glu-A1c allele showed higher SCSRC value (80.3) than cultivars with Glu-A1a or Glu-A1b allele (77.0 and 75.3, respectively). Korean wheat cultivars carrying Glu-B1i allele showed higher LASRC value (157.2) than Glu-B1b and Glu-B1f allele (108.3 and 105.4, respectively). Averages of SucSRC values in Glu-A1c and Glu-A3d alleles were higher than their counterpart alleles, but there were no significant differences for SRC values between Pin-1 , Glu-D1 and Glu-B3 alleles. 3.2. Dough and pasting properties Range of water absorption, mixing time and tolerance of Mixograph was 57.8–67.0%, 1.6–5.0 min and 6.0–20.3 mm, respectively (Table 1). Their averages were 60.2%, 2.9 min and 12.3 mm, respectively. Water absorption of Mixograph in Korean wheat cultivars carrying Glu-B1i allele (67.0%) was higher than that of Korean wheat cultivars with Glu-B1b or Glu-B1f allele (59.5 and 59.6%, respectively). Korean wheat cultivars carrying Glu-D1d allele showed longer mixing time of Mixograph (3.8 min) than cultivars with Glu- D1f allele (2.5 min). Korean wheat cultivars carrying Glu- B3h allele showed longer mixing time (4.0 min) and higher mixing tolerance (16.3 mm) than its counterpart allele, lower than 2.8 min and 12.8 mm, respectively. Korean wheat cultivars carrying Glu-B3h allele produced a higher maximum dough height because they also possess the Glu- D1d allele (Table 2). There were no significant differences in parameters of Mixograph between Pin-1 , Glu-A1 and Glu-A3 alleles. In pasting properties of starch, ranges of amylose content, peak viscosity, holding strength, final viscosity, breakdown, and setback were 25.8–29.0%, 71.7–160.3 BU, 39.3–102.7 BU, 163.7–339.7 BU, 20.3–73.7 BU, and 111.7–237.0 BU, respectively (Table 1). 3.3. Steamed bread quality Differences of steam bread quality attributes of two types of steamed bread are summarized in Table 3 (Appendix B for each Korean wheat cultivar). KSSB showed higher diameter (139.8 mm) and volume (688.6 mL) than those of NSCSB (103.2 mm and 475.0 mL, respectively). NSCSB showed higher height (63.6 mm) and whiteness index of crumb (74.9) than those of KSSB (60.0 mm and 69.5, respectively). There was no significant difference in whiteness index of surface between two types of steamed bread. KSSB showed higher stress relaxation (20.3%) and lower hardness (7.1 N) of crumb than those of NSCSB (17.7% and 15.0 N, respectively). Surface and crumb structure of two types of steamed bread, KSSB and NSCSB are shown in Fig. 3. KSSB showed a larger reduction in volume than NSCSB when it is taken out of the steamer, although KSSB had larger bread loaf volume than NSCSB due to the higher water absorption and different ingredients. KSSB also showed higher stress relaxation and softer texture of crumb and more porous of crumb structure than NSCSB because Korean consumers prefer soft texture. Jojoong and Jokyung are the most suitable cultivars for NSCSB and KSSB, respectively, because of smoothness of surface, uniform structure of crumb and high volume. Hojoong, a partial waxy wheat cultivar showed softer texture than other cultivars regardless of NSCSB or KSSB, but a lot of inappropriate bubbles found on surface of KSSB and lower height and unsuitable crumb structure in NSCSB. Joongmo 2008, a Korean wheat cultivar with high protein content was unsuitable for steamed bread because of squashed surface, unsuitable crumb structure, low bread loaf volume and harder texture of steamed bread. Correlations between flour characteristics and two types steamed bread quality are summarized in Table 4. Diameter of KSSB was correlated with mixing time, final viscosity and setback while diameter of NSCSB was correlated with SDS sedimentation volumes. Height of KSSB was correlated with average of particle size of wheat flour, damaged starch content, mixing time and mixing tolerance of Mixograph, final viscosity and setback while height of NSCSB was correlated with only protein content. Volume of KSSB was Table 3 Differences in steamed bread quality attributes of Korean style steamed bread (KSSB) and northern-style Chinese steamed bread (NSCSB) prepared from Korean wheat cultivars Characteristics KSSB NSCSB Bread properties Diameter (mm) 139.8±6.0 a (133.6–151.0) 103.2±5.2 b (93.0–110.0) Height (mm) 60.0±4.8 b (50.5–65.2) 63.6±3.5 a (58.5–69.4) Volume (mL) 688.6±41.6 a (612.5–762.5) 475.0±32.1 b (375.0–475.0) Whiteness index of surface 75.9±2.7 a (71.4–79.7) 76.8±2.0 a (72.7–80.1) Whiteness index of crumb 69.5±2.0 b (65.2–72.2) 74.9±2.1 a (70.8–78.4) Textures properties Stress relaxation (%) 20.3±1.5 a (18.5–22.8) 17.7±1.7 b (15.5–21.8) Hardness (N) 7.1±1.1 b (5.3–8.8) 15.0±4.4 a (8.9–22.2) Data are average±standard deviation, ranges from Korean wheat cultivars described within parentheses. Values followed by same letters within same characteristic are not significantly different at P <0.05.