New Type of Food Processing Material: The Crystal Structure and Functional Properties of Waxy and Non-Waxy Proso Millet Resistant Starches

Resistant starch (RS) is widely used in the food industry because of its ability to regulate and protect the small intestine, but their distinct effects on the structural and functional properties of waxy and non-waxy proso millet starches are not completely understood. The crystalline structure and physicochemical properties of waxy and non-waxy proso millets’ starch samples were analyzed after heat-moisture treatment (HMT). The analysis revealed significant differences between the RS of waxy and non-waxy proso millets. The crystal type of proso millets’ starch changed from type A to type B + V. The relative crystallinity of the RS of waxy proso millet was better than that of non-waxy proso millet. The gelatinization temperature and thermal stability of RS significantly increased, and the pasting temperature (PTM) of the RS of waxy proso millet was the highest. The water solubility and swelling power of the RS in proso millet decreased, and the viscoelasticity improved. The correlation between the short-range ordered structure of RS and ΔH, and gelatinization properties has a stronger correlation. This study provides practical information for improving the nutritional benefits of waxy and non-waxy proso millet in food applications.

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Morphological, Structural and Functional Properties of Starches from Different Legume Resources

Legume Research - An International Journal ◽

10.18805/lr-599 ◽

2021 ◽

Author(s):

X.Y. Chen ◽

X.W. Ma ◽

J.Y. Wen ◽

X.C. Liu ◽

X.R. Yu ◽

...

Keyword(s):

Functional Properties ◽

Water Solubility ◽

Spherical Shape ◽

Pigeon Pea ◽

X Ray Diffraction ◽

Relative Crystallinity ◽

Large Size ◽

Structural And Functional Properties ◽

Development And Utilization ◽

Pea Starch

Background: Legume is well known for its high nutrition and health care values. Considering that starch is the main carbohydrate in legume, its properties directly affect the development and utilization of legume resources. Methods: Starches were extracted from the seeds and root tubers of five legumes. The morphological, structural and functional properties of the starches were investigated and compared using scanning electron microscopy, X-ray diffraction and attenuated total reflectance-Fourier transform infrared spectroscopy.Result: The granules of kudzu, broad bean and pigeon pea starches were kidney-shaped with a large size, while groundnut and white pea starches were small granules with a mixture of irregularly polyhedral and spherical shape. The five legume starches had different apparent amylose contents and exhibited remarkably different crystalline properties. Among the samples, the relative crystallinity of kudzu starch was the highest, while pigeon pea starch had the highest short-range ordered degree. The swelling power and water solubility of the five legume starches were also varied. Furthermore, white pea starch is more susceptible to acid and enzymatic hydrolysis than the four other starches. The results are important for the processing and utilization of legume starches and can provide reference for the development of legume-based functional food.

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Effects of Different Isolation Media on Structural and Functional Properties of Starches from Root Tubers of Purple, Yellow and White Sweet Potatoes

Molecules ◽

10.3390/molecules23092135 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2135 ◽

Cited By ~ 5

Author(s):

Ahui Xu ◽

Ke Guo ◽

Tianxiang Liu ◽

Xiaofeng Bian ◽

Long Zhang ◽

...

Keyword(s):

Thermal Properties ◽

Functional Properties ◽

Water Solubility ◽

Amylose Content ◽

Pasting Properties ◽

Sweet Potatoes ◽

Isolation Medium ◽

Peak Intensity ◽

Apparent Amylose Content ◽

Structural And Functional Properties

Different-colored sweet potatoes have different contents of pigments and phenolic compounds in their root tubers, which influence the isolation of starch. It is important to justify the identification of the most suitable isolation medium of starch from different colored root tubers. In this study, starches were isolated from root tubers of purple, yellow and white sweet potatoes using four different extraction media, including H2O, 0.5% Na2S2O5, 0.2% NaOH, and both 0.5% Na2S2O5 and 0.2% NaOH. Their structural and functional properties were investigated and compared among different extraction media. The results showed that the granule size, apparent amylose content, lamellar peak intensity, thermal properties, and pasting properties were different among different-colored sweet potatoes due to their different genotype backgrounds. The four extraction media had no significant effects on starch structural properties, including apparent amylose content, crystalline structure, ordered degree, and lamellar peak intensity, except that the NaOH and Na2S2O5 treatment were able to increase the whiteness of purple and yellow sweet potato starches. The different extraction media had some effects on starch functional properties, including thermal properties, swelling power, water solubility, and pasting properties. The above results indicated that the H2O was the most suitable extraction medium to simply and fast isolate starch from root tubers of different-colored sweet potatoes.

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Improving the Functionality of Proso Millet Protein and Its Potential as a Functional Food Ingredient by Applying Nitrogen Fertiliser

Foods ◽

10.3390/foods10061332 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1332

Author(s):

Honglu Wang ◽

Dongmei Li ◽

Chenxi Wan ◽

Yan Luo ◽

Qinghua Yang ◽

...

Keyword(s):

Functional Properties ◽

Amino Acid Content ◽

Control Group ◽

Foaming Properties ◽

Food Ingredient ◽

Nitrogen Fertiliser ◽

Proso Millet ◽

Structural And Functional Properties ◽

High Amino Acid ◽

Β Sheet

Nitrogen is required for proso millet growth and has a critical influence on yield and quality. However, the effect of nitrogen fertilisation on proso millet protein properties remains unclear. This study aimed to investigate how nitrogen fertiliser treatment (180 kg/hm2) affects the structural and functional properties of proso millet protein. In comparison with the control group (N0), nitrogen fertiliser treatment loosened the dense structure of the protein and presented a larger particle size. Nitrogen treatment did not change the main subunit composition, and β-sheet and α-helix were the main secondary structures of proso millet protein based on Fourier transform infrared spectroscopy. In addition, nitrogen fertiliser treatment improved the content of hydrophobic amino acids and β-sheet proportion from proso millet protein, and high water/oil absorption capacity and thermal stability was observed, but the solubility, emulsion stability and foaming properties from proso millet protein decreased. Proso millet proteins exhibited high amino acid content and good functional properties, including solubility, foaming capacity and emulsifying properties, especially the w139 variety. Results show that proso millet protein has great potential for food applications. The above results provide useful information for the food industry to determine emerging gluten-free protein resources.

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Structural and Film-Forming Properties of Millet Starches: A Comparative Study

Coatings ◽

10.3390/coatings11080954 ◽

2021 ◽

Vol 11 (8) ◽

pp. 954

Author(s):

Sneh Punia Bangar ◽

Anil Kumar Siroha ◽

Manju Nehra ◽

Monica Trif ◽

Vandana Ganwal ◽

...

Keyword(s):

Water Solubility ◽

Animal Feed ◽

Amylose Content ◽

Light Transmittance ◽

Major Constituent ◽

Alternative Source ◽

Relative Crystallinity ◽

Proso Millet ◽

Film Forming ◽

Forming Characteristics

Millets are an underutilized and important drought-resistant crop, which are mainly used for animal feed. The major constituent in millet is starch (70%); millet starch represents an alternative source of starches like maize, rice, potato, etc. This encouraged us to isolate and characterize the starches from different millet sources and to evaluate the application of these starches in edible film preparation. In the present study, the physicochemical, morphological, and film-forming characteristics of millet starches were studied. The amylose content, swelling power, and solubility of millet starches ranged from 11.01% to 16.61%, 14.43 to 18.83 g/g, and 15.2% to 25.9%, respectively. Significant differences (p < 0.05) were found with different pasting parameters, and the highest peak (2985 cP), breakdown (1618 cP), and final viscosity (3665 cP) were observed for barnyard, proso, and finger millet starch, respectively. Little millet starch achieved the highest pasting temperature. All starches showed A-type crystalline patterns, and relative crystallinity was observed at levels of 24.73% to 32.62%, with proso millet starch achieving the highest value. The light transmittance of starches varied from 3.3% to 5.2%, with proso millet starch showing the highest transparency. Significant differences (p < 0.05) were observed in the water solubility, thickness, opacity and mechanical characteristics of films. The results of the present study facilitate a better assessment of the functional characteristics of millet starches for their possible applications in the preparation of starch films.

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