Addition of 1, 4-α-glucan branching enzyme during the preparation of raw dough reduces the retrogradation and increases the slowly digestible fraction of starch in cooked noodles. (March 2022)

• Record Type: Journal Article
• Authors: Ji, Xiangqing; Zeng, Cheng; Yang, Dingkuan; Mu, Siyu; Shi, Yu; Huang, Yicheng; Lee, Byung-Hoo; Li, Dan; Li, Xiaolei
• Is Part Of: Journal of cereal science. Volume 104(2022)
• Publication Date: 2022-03
• Subjects: Retrogradation -- Digestibility -- Branching enzyme -- Noodle; Grain -- Periodicals; Cereal products -- Periodicals; Céréales -- Périodiques; Produits céréaliers -- Périodiques; Cereal products; Grain; Periodicals; 664.705
• DOI: 10.1016/j.jcs.2022.103431
• Languages: English
• ISSNs: 0733-5210

Abstract

Abstract: Consumers significantly prefer wheat noodles that offer both an acceptable texture and health benefits. To this end, a cold-active 1, 4-α-glucan branching enzyme from Bifidobacterium longum (BlBE) was expressed in the generally recognized as safe (GRAS) host cell Bacillus subtilis and then used at 120, 240 or 480 U/g flour in the preparation of raw dough. The storage modulus and loss modulus of the BlBE-modified dough decreased, but the pseudo-plasticity increased. The cooked noodles' hardness, gumminess and chewiness decreased by 12.1%–45.8%, 9.7%–40.4% and 16.0%–42.4%, respectively, but both resilience and cohesiveness increased by 4.0%–14.8% and 1.8%–9.0%, respectively. Pearson analysis revealed a correlation between the noodles' textural parameters and the doughs' power law equation parameters. BlBE-modified noodles exhibited significantly (P < 0.05) lower differential scanning calorimetry retrogradation enthalpies during storage at 4 °C for 7 days and released significantly lower levels of glucose during incubation with mammalian α-glucosidase at 37 °C for 10 min–360 min. BlBE at 480 U/g flour increased the slowly digestible portion by 12.6%. BlBE decreased the molecular weight, x-ray diffraction crystallinity, and fourier transform infrared spectroscopy ratio of band's heights at 1045 cm −1 and 1022 cm −1 of starch but increased the amylopectin content and ratio of short- to long-branch chains. These structural changes in starch partially explained the reduced retrogradation and enhanced slowly digestible starch fraction in the noodles. Graphical abstract: Image 1 Highlights: 1, 4-α-glucan branching enzyme from Bifidobacterium longum (BlBE) was expressed in Bacillus subtilis . BlBE reduced the modulus of viscoelasticity of wheat flour dough. Power-law equations of doughs are related to textural properties of noodles. BlBE-modified noodles had slow digestion and low retrogradation. BlBE could reduce long branches and increase short branches of starch in noodle.