Molecular rearrangement of Laird lentil (Lens culinaris Medikus) starch during different processing treatments of the seeds. (June 2018)

• Record Type: Journal Article
• Authors: Yin, Xiuxiu; Ma, Zhen; Hu, Xinzhong; Li, Xiaoping; Boye, Joyce I.
• Is Part Of: Food hydrocolloids. Volume 79(2018)
• Page Start: 399
• Page End: 408
• Publication Date: 2018-06
• Subjects: Lentil seeds (Lens culinaris) -- Processing treatment -- Starch isolation -- Structural characterization -- Molecular order; ULS lentil starch from untreated seeds -- RLS lentil starch from roasted seeds -- GLS lentil starch from germinated seeds -- FLS lentil starch from fermented seeds -- MLS lentil starch from microwave cooked seeds -- CLS lentil starch from conventional cooked seeds -- ALS lentil starch from autoclaved seeds -- XRD X-ray diffraction -- SAXS small angle X-ray scattering -- SEC-MALLS size exclusion chromatography equipped with a multiangle laser light scattering detector -- FT-IR Fourier transform infrared spectroscopy -- SEM scanning electron microscopy -- 13C-NMR solid state 13C-nuclear magnetic resonance -- DO degree of order -- DD degree of double helix -- PPA proportion of amorphous phase; Hydrocolloids -- Periodicals; Food additives -- Periodicals; Colloïdes -- Périodiques; Aliments -- Additifs -- Périodiques; Colloids; Food additives; Periodicals; Electronic journals; 664.06
• DOI: 10.1016/j.foodhyd.2018.01.012
• Languages: English
• ISSNs: 0268-005X

Abstract

Abstract: The molecular structural changes of the starch isolated from untreated (ULS), roasted (RLS), germinated (GLS), fermented (FLS), microwave cooked (MLS), conventional cooked (CLS), and autoclaved (ALS) lentil seeds were investigated. All starch samples obtained were categorized by size exclusion chromatography with multi-angle laser scattering into two groups, i.e., Group A with two population of peaks appeared for samples including ULS, RLS, and GLS; and Group B with three population of peaks shown in samples including FLS, MLS, CLS and ALS. A noticeable decrease in relative crystallinity by XRD was found for all starch from the processed seeds (11.41–3.24%) compared with starch isolated from untreated seeds (15.90%), especially that a greater extent of such decreasing was observed for FLS, MLS, CLS, and ALS (Group B samples). The intensity of the absorptions related to hydrogen bonding by FT-IR (3000-3600 cm −1, and ∼1000 cm −1 ) were markedly decreased for lentil starch isolated from processed seeds compared with native starch, and, especially for treated samples of Group B, which also exhibited the significantly higher degree of double helix and lower value of degree of order. Small angle X-ray scattering data manifested that the typical ∼9–10 nm semi-crystalline structure was disappeared for the Group B samples which were characterized with the relatively higher values of d, d a, and d c . The results suggested that the densely packed crystalline structure could be shifted within the crystallites and tended to result small new crystal structure during the processing of lentil seeds, and such effect was particularly obvious for starch samples including FLS, CLS, MLS, and ALS. Graphical abstract: Image Highlights: Starch with small molecular chain are not in favor for perfect crystallite formation. Absorption intensity related to starch H-bonding were decreased for processed lentil. Typical 9–10 nm semi-crystalline structure was disappeared for some processed lentils. Variations in double helices and crystallinity are consistent with their SAXS results. Small new crystal structure tends to be formed during processing of lentil seeds.