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Key research themes
1. How do starch structural characteristics influence its digestibility and nutritional properties?
This research area focuses on elucidating the relationships between the molecular and granular structure of starch from various botanical sources and its digestibility profile, particularly regarding resistant starch (RS) and slowly digestible starch (SDS). Understanding these relationships is crucial because starch's digestibility directly impacts glycemic response and gut health, influencing nutritional quality and potential health benefits of starch-containing foods. Research investigates structural features such as amylose/amylopectin ratio, granule size and morphology, branching pattern, crystalline type (A, B, or C), and molecular weight distribution, and how these modulate enzymatic accessibility and digestion kinetics.
Key finding: Identifies that B-type crystalline starches exhibit higher resistant starch content, and starches with higher amylopectin content (A-type pattern) generally have higher slowly digestible starch levels; the granule size and... Read more
Key finding: Develops a predictive model correlating starch microstructure, gelatinization temperature, amylose and amylopectin content, total starch, and resistant starch fraction in rice. Finds that higher gelatinization temperature and... Read more
Key finding: Demonstrates that starch digestibility in cereal-based foods (bread, pasta, cookies) varies significantly due to matrix effects including physical structure and processing method. Gluten-free and whole-wheat variants show... Read more
Key finding: Shows that food-grade chemically modified starches exhibit up to a 10% reduction in in vitro digestibility compared to native starch, with digestibility inversely related to degree of substitution but in a non-linear manner.... Read more
Key finding: Identifies that different native potato varieties with distinct granule size distributions and amylose contents exhibit variable resistant starch fractions after cooking, with higher amylose and phosphorous content... Read more
2. What advanced analytical and microscopic techniques best characterize starch structure and functionality in food systems?
Research under this theme investigates the application and comparative utility of modern analytical methodologies for detailed multi-scale characterization of starch structure—from molecular to granular levels—and functional assessments in diverse food matrices. Technologies include light microscopy (LM) with iodine staining, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), chromatographic techniques, and rheological measurements. These tools enable correlation of starch supramolecular architecture and composition to physicochemical and functional properties, essential for starch utilization in food products.
Key finding: Demonstrates the effectiveness of iodine-stained light microscopy to distinguish amylose and amylopectin distributions in starch granules, enabling visualization of gelatinization and molecular dispersion in food matrices.... Read more
Key finding: Presents a comprehensive overview of multi-level starch characterization approaches including XRD, NMR, chromatography, and mass spectrometry, emphasizing the hierarchical structural organization from granule morphology to... Read more
Key finding: Applies microscopic use-wear and plant residue analyses on Upper Paleolithic grinding tools, demonstrating the capability of combined microstructural and residue-based microscopic techniques to identify starch granules and... Read more
Key finding: Utilizes rheological characterization (pasting profiles, flow behavior) of native and binary-mix starch systems within various food matrices (mayonnaise, pudding, ketchup, jelly) demonstrating matrix-dependent rheological... Read more
Key finding: Uses FTIR spectroscopy coupled with physicochemical assays and pasting property measurements to reveal that starch modifications (oxidation, acetylation, pregelatinization, acid thinning) alter absorption capacity, viscosity,... Read more
3. How do botanical source and genetic variation affect starch physicochemical properties and industrial applicability?
This theme explores the diversity of starch physicochemical and functional properties as influenced by botanical origin, genotype, and genetic modification, with implications for starch industrial applications and nutritional qualities. Studies analyze starches from non-traditional sources (e.g., quinoa, proso millet, arrowroot, native potatoes) and genetically distinct maize genotypes (waxy, high amylose), highlighting how genotype-dependent differences in amylose content, granule morphology, crystalline types, and branching influence starch isolation yield, pasting behavior, digestibility, and potential end-uses. Such insights inform breeding and selection programs aimed at customized starches for food and non-food industries.
Key finding: Reveals that starches isolated from diverse non-traditional sources (quinoa, lentil, arrowhead, proso millet, purple potato, etc.) present significant variation in granule morphology, amylose content (11.46–37.61%),... Read more
Key finding: Reviews large- and laboratory-scale isolation and characterization techniques for unconventional starches from underutilized botanical sources and food waste. Emphasizes the impact of amylose content, granule size,... Read more
Key finding: Demonstrates that maize starches from genotypes waxy (wx), high amylose (ae), sugar (su), and wild type (WT) show distinctive physicochemical and thermodynamic profiles related to differing activities of starch synthases and... Read more
Key finding: Characterizes pearl millet starches as low amylose non-waxy types with A-type XRD pattern and low resistant starch content, correlated with high starch digestibility. Unique swelling and solubility profiles linked to granule... Read more
Key finding: Characterizes arrowroot starch isolated from Sri Lankan tubers, documenting its high purity, predominance of oval and irregular granules averaging 44.99 μm length, A-type crystalline pattern, high viscosity, and thermal... Read more