Millet Starch Research Articles

Recent Advancements on Barnyard Millet Starch: A Sustainable Alternative to Conventional Starch

AbstractThe global demand for starch has been steadily increasing, driven by various industries such as food, pharmaceuticals, and textiles. However, conventional starch sources, such as corn and wheat, are associated with significant environmental concerns and resource depletion. Therefore, there is a growing need to explore sustainable alternatives to conventional starches. Barnyard millet starch can be a promising sustainable alternative to conventional starch. The starch extracted from barnyard millet exhibits unique physicochemical properties, including high amylose content, small granule size, and good gel‐forming ability. These properties make it suitable for various industrial applications. In the food industry, it can be used as a thickening agent, stabilizer, and fat replacer in various products, including sauces, soups, bakery items, and dairy alternatives. Moreover, barnyard millet starch shows promise in the textile industry as a sizing agent and for producing biodegradable films. However, challenges related to scaling up production, processing techniques, and market acceptance must be addressed to realize the potential of barnyard millet starch fully. Embracing barnyard millet starch can contribute to a more sustainable and resource‐efficient future, reducing the ecological footprint associated with starch production. This review article focuses on the properties, modifications, functionality, and applications of barnyard starch.

The impact of addition of pearl millet starch-germ complex in white bread on nutritional, textural, structural, and glycaemic response: Single blinded randomized controlled trial in healthy and pre-diabetic participants

The rise of pre-diabetes at the global level has created a significant interest in developing low glycaemic index food products. The pearl millet is a cheaper source of starch and its germ contains significant amount of protein and fat. The complexing of pearl millet starch and germ by dry heat treatment (PMSGH) resulted an increase in the resistant starch content upto 45.09 % due to formation of amylose-glutelin-linoleic acid complex. The resulting pearl millet starch germ complex was incorporated into wheat bread at 20, 25, and 30 %. The PMSGH incorporated into bread at 30 % reduced the glycaemic index to 52.31. The PMSGH incorporated bread had significantly (p < 0.05)increased in the hardness with a reduction in springiness and cohesiveness. The structural attributes of the 30 % PMSGH incorporated bread revealed a significant (p < 0.05)increase in 1040/1020 cm−1 ratio and relative crystallinity. The consumption of functional bread incorporated with pearl millet starch germ complex reduced blood glucose levels and in vivo glycaemic index in healthy and pre-diabetic participants when compared to white bread. Hence, the study showed that the incorporation of pearl millet starch-germ complex into food products could be a potential new and healthier approach for improving dietary options in pre-diabetes care.

Comprehensive Characterization of Starch from Diverse Sources: Physicochemical, and Functional Properties

AbstractThe present study is based on the comprehensive characterization of starches from pearl millet, sorghum, mango kernel, and water chestnut. The starches are analyzed to observe the difference in physicochemical, pasting, rheological, Fourier transform infrared spectroscopy (FTIR), and X‐ray diffraction (XRD) properties. The amylose content from diverse sources ranges from 17.3 to 26.3%. The swelling power and solubility of the starches are influenced by the increase in temperature. It is observed that an increase in temperature results in increased swelling power and solubility. At 90 °C, mango kernel starch shows the highest swelling power while pearl millet starch shows the lowest. The botanical sources influence the pasting and rheological properties, and a significant difference (p &lt; 0.05) is observed in all the parameters recorded. The peak viscosity (PV) of starches ranges from 1256 to 2101 cP. All the starches possess almost similar and typical starch FTIR spectra. The starches from all sources show prominent peaks at 15.2, 17, 18.3, and 23 (2θ), corresponding to a typical A‐type starch crystallinity organization.

Thermodynamic and network characteristics of optimized lysine-modified kutki (Panicum sumatrense) millet starch hydrogels.

Three-dimensional polymeric network of hydrogels avoids its dissolution into the aqueous region. Hydrogels must have strong structural integrity to be used for drug/nutraceutical delivery. A three factor-three-level Box-Behnken design was used to understand the effects of starch concentration, NaCl, and pH on the textural and structural integrity of Lysine modified kutki millet starch hydrogels. Various kinetic models were fitted to the time-course measurement of shrinkage behavior of both conventionally (CDHG) and freeze-dried (FDHG) hydrogel. Increasing the swelling temperature (5-50°C) showed values of higher molecular weight of polymer chains between neighboring crosslinks (g/mol) for FDHG (9539.59-56,769.72) than CDHG (1096.28-11,420.48). Similarly, mesh size (ξ) was more for FDHG (38.63-109.53 Ȧ) than CDHG (10.97-42.74 Ȧ). However, other network parameters such as polymer volume fraction ( ) was lower for FDHG (0.229-0.146) than CDHG (0.3882-0.222). These values suggest low swelling power of CDHG compared to FDHG. Thermodynamically, FDHG took less energy to swell than CDHG. The study showed that FDHG has better properties than CDHG and could be employed in nutraceutical delivery. The online version contains supplementary material available at 10.1007/s13197-024-05953-x.

Structural, physicochemical and functional properties of high-pressure modified white finger millet starch

The effect of high-pressure processing (HPP) modification (200, 400, and 600 MPa for 10 min) on the physico-chemical, functional, structural, and rheological properties of white finger millet starch (WFMS) was studied. Measured amylose content, water, and oil absorption capacity, alkaline water retention, and pasting temperature increased significantly with the intensity of pressure. All color parameters (L, a, b values, and ΔC) were affected by HPP treatment, and paste clarity of modified starch decreased significantly with an increase in storage time. The samples' least gelation concentration (LGC) is in the range of 8–14 %. An increasing solubility and swelling power are noted, further intensifying at the elevated temperature (90 °C). The structural changes of WFMS were characterized by XRD, SEM, and FTIR spectroscopy. Starch modified at 600 MPa showed a similar pattern as ‘B’-type crystalline, and the surfaces of starch deformed because of the gelatinization. Applied pressure of 600 MPa affected the FTIR characteristic bands at 3330, 2358, and 997 cm−1, indicating a lower crystallinity of the HPP-600 modified sample. According to DSC analysis, even at 600 MPa, WFMS is only partially gelatinized. This work provides insights for producing modified WFM starches by a novel physical modification method.

Influence of solid-state fermentation on the functional characteristics of pearl millet starch: An innovative and cost-efficient approach to modify starch

The current investigation aimed to assess how the fermentation process impacts pearl millet starch. Two distinct fungi, Rhizopus azygosporus and Aspergillus sojae, were employed to alter the structure of starch granules. Fermentation led to the creation of pores on the surface of the starch granules. A comparative examination of the fungal strains revealed that Aspergillus sojae fermentation resulted in the highest number of pores in pearl millet starch when compared to Rhizopus azygosporus. The particle size of the starch granules experienced a significant reduction following fermentation. Moreover, noticeable changes were observed in the amylose content, swelling capacity, and solubility of pearl millet starch. An increase in both the amylose content and solubility of pearl millet starch was noted, with values shifting from 14.27 % to 15.96 % and 17.37 % to 20.41 %, respectively. Additionally, the starch extracted from fermented pearl millet displayed a significant decrease in swelling power, decreasing from 15.53 g/g to 13.15 g/g. These findings affirm that solid-state fermentation holds promise as an innovative and cost-effective method for starch modification.

Finger millet starch extraction: Comparative analysis of solvent efficiency, yield, and colour attributes

Finger millet starch extraction: Comparative analysis of solvent efficiency, yield, and colour attributes

Role of Varieties of Starch in the Development of Edible Films—A Review

AbstractStarch, a stored form of energy in plants, plays an important role in the human diet as it is a vital source of carbohydrate. The classification of starch based on its botanical origin as cereal starch, tuber starch, and millet starch gives a new dimension to starch classification. The starches generally have an amylose (AM) content of 20–30%, amylopectin (AP) of 70–80% and gelatinization temperature of 60–95°C. Conventionally, starch is used in the food industry as a thickening agent and flavor enhancer in soups, sauces, bakery, and confectionery products. But, the less explored area is its utilization in the manufacture of edible films. Starch, due to its plasticizing effect, gelatinization, and pasting property produces film with desirable tensile strength (TS), elongation at break (EAB), and water vapor permeability (WVP). Starch films are not only biodegradable and renewable, but also possess excellent barrier properties. These films produced by wet and dry processing techniques can be used to package confectioneries, meat, sea foods, fruits, and vegetables. In the recent times, superhydrophobic, active, and agro‐waste based edible films have gained industrial importance.

Investigating the effect of natural fermentation in modifying the physico-functional, structural and thermal characteristics of pearl and finger millet starch.

In recent years, millets are often considered an emerging crop for sustainable agriculture. Therefore, millets can be exploited as an alternative source of starch which has many applications ranging from food, packaging, bioplastics, and others. However, starch is seldom used in its native form and is more often modified to enhance its functional properties. In literature, many traditional millet-based food recipes often incorporate a fermentation step before cooking. Therefore, using this traditional knowledge fermentation has been explored as a potential method for modifying millet starch. Pearl millet (PM) and finger millet (FM) flour were allowed to naturally ferment for 24 h followed by starch extraction. Compared to native (N) starch,water/oil holding capacity and least gelation concentration of fermented (F) starch decreased with no significant change in swelling power. The solubility, paste clarity and in vitro digestibility of starch were significantly affected by fermentation. X-ray diffraction (XRD) data indicates that after fermentation, crystallinity increased while the A-type crystalline structure remained intact. Fourier-transform infrared (FTIR) spectra showed no deletion or addition of any new functional groups. Thermal characterization by differential scanning calorimetry (DSC) showed that the enthalpy of gelatinization of PM starch decreased while that of FM starch increased after fermentation. The results indicate that 24 h natural fermentation had a significant impact on functional properties of starch without altering the structural architecture of starch granules. Therefore, fermentation can be further explored as a low-cost alternative for starch modification. © 2023 Society of Chemical Industry.

Effects of Wet‐Milling Extraction Methods on Nutritional, Functional, and Structural Properties of Barnyard Millet Starch

AbstractStarch is the main integral components of the millets and it is widely used in the food processing sectors for development of functional foods. The extraction and isolation methods of starch from millet grains are greatly affected their functional and structural properties. Therefore, in current study, the effects of different wet milling extraction methods such as water, acidic, and alkaline are investigated on the physical, structural, thermal, and functional properties of barnyard millet starch. The results show that the starch extracted from barnyard millets using alkaline method shows higher yield of starch (64.76%) with good amylose content (34.52%). In addition, the functional properties such as water binding capacity (211.39%), oil binding capacity (223.84%), higher color attributes (whiteness), thermal stability (91.62 °C), textural properties (74.70 g), and lower particle size (19.44 µm) are recorded in barnyard millet starch extracted using alkaline steeping method. The results of the field emission scanning electron microscopes (FESEM) are showed polygonal, spherical, and rounded shapes of all types of extracted starch granules. Whereas, the acidic method is more fused structures of starch granules as compared to water and alkaline methods. The results of the current study reveal that the application of alkaline method is the most potential to extract starch from barnyard millet with good quality and functional properties for further food applications.

Effects of single and dual modifications with debranching and heat-moisture treatments on physicochemical, rheological, and digestibility properties of proso millet starch

The effects of single and dual modifications with heat-moisture treatment (HMT) and enzymatic debranching on the structural, physicochemical, rheological, and in-vitro digestibility properties of proso millet starch (PMS) were comparatively studied. Amylose content increased after gelatinization and all modification treatments. Debranching and dual modification (debranching followed by HMT) decreased the average chain length and swelling power but increased the solubility of PMS. HMT did not change the average chain length and chain length distribution in native and debranched starches but decreased the swelling power and solubility of native starch. The A-type X-ray diffraction pattern of PMS was converted to the A + V type by HMT and to the B + V type by debranching and dual modification. FTIR investigation showed that the short-range molecular order of all modified starches was disrupted. The viscoelasticity and viscosity of all starch pastes decreased in the following order: PMS > HMT starch > debranched starch > dual modified starch. In-vitro starch digestibility showed that HMT increased slowly digestible starch (SDS) to 32.88 %, while debranching increased resistant starch (RS) to 77.14 %. HMT increased RS to 86.17 % in the dual modified starch. Debranching therefore predominates in the dual modification of starch compared to HMT.

Impact of multi‐pin atmospheric cold plasma on dynamic rheological characteristics of kodo millet starch

AbstractKodo millet's popularity grows due to its diverse applications and health benefits, primarily as a starch source for industries like food processing, requiring modifications to overcome raw starch limitations. In this study, raw kodo starch underwent treatment with cold plasma, varying in voltage (10, 20, and 30 kV) and duration (10, 20, and 30 min). The treated samples were designated as S1 to S9. The results showed that the modified starch exhibited significantly higher G' and G" values compared to the control sample. Three different models were attempted to describe the flow behavior, with the most suitable model selected. This analysis led to an increase in yield stress from 86.55 to 217.98 Pa and an increase in the flow index from 0.31 to 0.56 for the modified starch. This understanding of the rheological characteristics of modified starch can be invaluable for innovating new products, blending novel ingredients, and optimizing manufacturing processes.Practical applicationsKodo millet has gained significant popularity in recent times owing to its high fiber content and low glycemic index. In this research, starch extracted from kodo millet underwent plasma treatment, resulting in a modified starch with enhanced functional properties. The study focused on exploring the rheological properties of this treated starch, and the findings revealed notable improvements in dynamic rheological parameters, including the storage modulus, loss modulus, and viscosity of the starch, all of which increased due to the plasma treatment. The enhanced viscosity makes kodo millet starch particularly suitable for a wide range of food applications. This modified starch finds practical use in the preparation of porridges, soups, and as a reliable filling agent in various food products. This emerging technology has captured the attention of food manufacturers in the grain processing sector, offering a means to elevate the quality and desirability of new food products.

Millet Starch – A Potential Functional Ingredient

Millets are primitive grains that were majorly cultivated in Indian subcontinent from ancient times. These are small seeded categorized as major and minor millets. Millets are resilient to adverse effects of climate change. They are regarded as "nutri-cereal" due to their high nutritional value compared to rice, wheat, and corn. Starch is the major nutritional constituent of millets with average content ranging from 55% to 61% in different millets. The application of millets depends on the physicochemical, structural, and functional properties of their starch. Millet starch is majorly isolated by wet milling methods, however, studies have shown the effect of dry milling on structural and functional properties of millet starches. Moreover, non-thermal methods have also been employed to enhance the functionality of millet starches. Studies have also demonstrated the functionality of millets in improvement of human metabolic heath and reduction of life-style related diseases. Modified millet starches are also utilised in food and non-food industries.

Acid Hydrolyzed Pearl Millet Starch Nanoparticles: Synthesis and Characterization

AbstractThe amylose content in native starch is reduced through hydrolysis, impacting its physicochemical properties. Starch nanoparticles exhibit enhanced water and oil absorption capacities, attributed to increased hydrolysis and subsequently higher solubility. Moreover, the swelling power of starch nanoparticles is notably higher, indicating improved functionality. Pasting properties are altered, with reduced peak viscosity, breakdown viscosity, and setback viscosity in modified starches. Dynamic light scattering reveals a significant reduction in particle size for starch nanoparticles compared to native starch. Morphological analysis using field emission‐scanning electron microscopy (FE‐SEM) highlights distinct granule shapes and surfaces between the two starch types. The X‐ray diffraction patterns confirm an A‐type crystalline structure in both native and modified starches. Fourier transform infrared (FTIR) spectroscopy verifies no significant difference in functional groups due to extraction or hydrolysis methods. This comprehensive investigation provides valuable insights into the chemical modification of pearl millet starch, shedding light on its potential applications in various industries, including food and pharmaceuticals.

The effect of lactic acid bacteria fermentation on physicochemical properties of starch from fermented proso millet flour

A waxy and a non-waxy proso millet flour were each fermented by Lactobacillus amylovorus, Lactobacillus fermentum, and Lactobacillus plantarum. The samples were fermented for one to five days, and starch was isolated from the fermented flours. The pH of fermented proso millet flour ranged from 3.27 to 3.6. The starch morphology of fermented samples differed from that of raw starches, with surface indentations and small pores leading to granule channels observed on the granule. The gelatinization temperatures were significantly decreased, whereas the enthalpies were not affected by fermentation. Peak and final viscosities were decreased after fermentation. The hardness of Lb. fermentum and Lb. plantarum fermented waxy starch gels was decreased, but the non-waxy samples fermented by Lb. amylovorus had significantly increased hardness. The adhesiveness of the starch gels from fermented samples was significantly increased. Lactic acid fermentation had significant effects on the morphology and physicochemical properties of proso millet starch.

Starch‐Based Biodegradable Film from Fruit and Vegetable Waste and Its Standardization Modules Based on Neural Networks and Response Surface Methodology

AbstractFruits and vegetable waste‐based starch has numerous applications for use as a biodegradable film in food packaging materials. This study reviews fruit and vegetable waste‐based non‐commercial starches that can be utilized as an alternatives for commercial starches in biodegradable film growth. Circular economy, sustainable manufacturing goals, recycling waste and by‐products, and new basic concepts drive the hunt for alternative starch sources. Starches from unusual and abandoned fruits and vegetables offer stronger research potential. The characteristics of starch extracted from these sources and their use as a biodegradable film are emerging trends in the field of packaging technology. Further, millet starch, for example, is made from the waste of underused crops or other fruits and vegetables and presents a wealth of new avenues for biodegradable film study. In order to cease throwing away valuable carbohydrates, especially starch, these sources must incorporate into the concept of “circularity” and work toward more sustainable manufacturing practices. Besides, optimizing the biodegradable film composition to improve barrier and shelf life is also crucial. Thus, an additional study may apply response surface‐based hybrid optimization, neural networks, or deep learning‐oriented models to optimize biodegradable film composition and intelligent monitoring of the materials under the packing systems.

Molecular morphology & interactions, functional properties, rheology and in vitro digestibility of ultrasonically modified pearl millet and sorghum starches

The present research investigated to study the effect of ultrasound treatment on isolated pearl millet starch (PMS) and sorghum starch (SS). Ultrasonication was applied to PMS and SS for 10, 15, and 20 min. Ultrasonically modified pearl millet and sorghum starches evaluated for their techno-functionality, pasting profile, morphology, in vitro starch digestibility, XRD, and molecular interactions. Ultrasound treatment increased water and oil absorption capacity, swelling power, and solubility with treatment time. For ultrasonicated PMS and SS, a significant increase (p < 0.05) in paste clarity (PC) (70.05 % and 67.23 %), freeze-thawing stability (FTS), gel consistency (GC) (25.05 mm and 32.95 mm), and in vitro starch digestibility were observed (57.70 g/100 g and 50.29 g/100 g), whereas no significant changes were recorded for the color values after the ultrasound treatment. Variations in pasting property were also observed in ultrasonicated starches with treatment duration. SEM images confirmed ultrasonication mainly forms pores and indentations on starch granule surface. FTIR spectra and X-ray diffractogram for ultrasonicated starches revealed a slight decrease in the peak intensity and A-type X-ray pattern with lower relative crystallinity (RC) than the native starches. G′ > G″ value, indicating the elastic behavior and lower tan δ value, depicting viscous behavior and high gel strength.

Preparation, structure, and in-vitro hypoglycemic potential of debranched millet starch-fatty acid composite resistant starch

Currently, the preparation methods and basic physicochemical properties of starch-FA complexes have been widely studied; however, no in-depth research on the regulatory mechanism of the digestive properties of debranched starch-unsaturated FA complexes has been conducted. Therefore, six fatty acids with different carbon chains and different degrees of unsaturation were complexed with de-branched millet starch in this research, using the microwave method. Microwave millet starch-linoleic acid complex (MPS-LOA) had the highest resistant starch (RS) content, and the structure and physicochemical properties of MPS-LOA were determined using various molecular techniques. The results indicate that MPS-LOA had a resistant starch (RS) content of 40.35% and the most notable fluorescence. The characteristic UV peaks of MPS-LOA were blue-shifted, and new IR peaks appeared. The crystalline structure changed to V-type crystals, the crystallinity increased, and the molecular weight decreased. The enthalpy and coagulability of MPS-LOA increased, and the swelling force decreased. Additionally, MPS-LOA showed enhanced α-glucosidase and α-amylase inhibition, and in-vitro hydrolysis kinetics analysis of MPS-LOA showed a hydrolysis index of 53.8 and an extended glycemic index (eGI)I of 54.6, indicating a low eGI food suitable for consumption by people with type II diabetes. These results provide a theoretical basis for the preparation of amylopectin- and starch-based foods with an anti-enzyme structure and a low glycemic index (GI).

Dry Heat Treatment of Finger Millet Starch for Thin Films—Studies on Physicochemical, Mechanical, and Barrier Properties

AbstractThis research work aims to investigate the impact of dry heat treatment (DHT) on the morphological, structural, and physicochemical properties of native finger millet starch (FMS), with the goal of enhancing its applicability in thin films. The influence of DHT on FMS is examined through various parameters, including moisture content, amylose content, ash content, swelling power, and solubility. Subsequently, a sequential evaluation is conducted to assess the morphology, structural and thermal stability, film thickness, water vapor permeability, water solubility, and mechanical properties of thin films produced from both FMS and DHT‐modified FMS. Regarding the modification of FMS, the solubility of FMS exhibits improvement, while amylose content, swelling, ash, and moisture content exhibit a decline. Thin films fabricated using DHT‐modified FMS displays enhanced homogeneity and continuity, devoid of cracks and holes typically observed in native FMS‐based thin films. Furthermore, the mechanical properties, water solubility, and water vapor permeability of the films are also improved as a result of the DHT treatment.These results demonstrate that DHT can be useful for enhancing the physical and chemical properties of high amylose finger millet starch for its applications in edible films and coatings.

Morphological, physicochemical, and functional properties of 15 different dietary carbohydrate sources in Sri Lanka

AbstractBackgroundCarbohydrate is the primary source of energy in the human diet and plays an important role in a healthy diet. In this study, 15 different carbohydrate sources (white raw rice, red raw rice, white basmati rice, red basmati rice, wheat, atta flour, soy, black gram, corn, finger millet, water lily seeds, kithul, chickpea, oats, and palmyra sprouts) in Sri Lanka were investigated for their physicochemical and functional properties.ResultsThe shape of the extracted starch granules varied according to the source, and the amylose content ranged from 17.22% to 36.12%. Kithul and black gram showed the highest water swelling capacity and water absorption index, respectively. Flour of white raw rice and finger millet showed significantly higher (p &lt; 0.05) freeze–thaw stability than other sources. Flour of Soy, black gram, and chickpea showed significantly higher (p &lt; 0.05) dietary fiber content and potassium content than other samples. Water lily seeds showed remarkable in vitro prebiotic activity from the studied carbohydrate sources.ConclusionThe study indicates the potential utilization of raw white rice, palmyra, and finger millet starch in the food processing industry as alternatives to conventional starch sources. Furthermore, the flour from water lily seeds, white basmati rice, soy, and black gram has the potential for use in functional food preparation, offering a wide range of health benefits.