Starch Varieties Research Articles

Resistant starch from plantain (Macho Musa paradisiaca L.) and banana (Roatan Musa sapientum L.) varieties crosslinked with epichlorohydrin

Resistant starch from plantain (Macho Musa paradisiaca L.) and banana (Roatan Musa sapientum L.) varieties was chemically modified by crosslinking using epichlorohydrin (EPI). These modified starches were subjected to in vitro digestibility studies using the Englyst method to determine the content of rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS). The thermal stability of these crosslinked starches was evaluated by gelatinization and retrogradation analyses, and their enthalpies were determined using differential scanning calorimetry (DSC). Additionally, their functional properties were evaluated. Chemical modification with EPI significantly increased the RS content in both starch varieties compared to that in native starch. The enthalpy and gelatinization temperature decreased in the EPI-modified starches of both varieties, indicating lower thermal stability during the gelatinization process compared to that of native starch. In general, both varieties of crosslinked plantain starch had lower viscosity (0.43 Pa*s) than did native starch (0.58 Pa*s). The results indicates that this starch crosslinked with EPI constitutes an alternative for use in food for people with health problems such as high cholesterol levels or postprandial insulin concentrations.Graphical

Research on electron beam irradiation in the multiscale structure of starch and its related applications: A review.

Electron beam irradiation (EBI), as a typical "green" emerging technology, can effectively alter the functional properties of starch by influencing its microstructure. This alteration enables starch to meet the current demands of consumers and the market for "health food." This paper reviews studies on modifying various starches using EBI and describes the changes in microstructure, physicochemical properties, and functional properties induced by this method. Additionally, the effects of EBI on starch-containing food products are discussed, along with issues to be addressed and research gaps in the synergistic treatment of modified starch. It is noted that the source, irradiation dose, and irradiation time all influence the effectiveness of starch modification. Given the characteristics of EBI technology, integrating physical, chemical, and biological modification methods can optimize the modification process and enhance efficiency. This technology can potentially diversify modified starch varieties and expand their applications. Furthermore, there remains significant research potential in producing modified starch using EBI technology and applying it to the food industry.

Valorization of Taioba Products and By-Products: Focusing on Starch.

Unconventional food plants, popularized in Brazil as PANC, remain underutilized globally. In that sense, this study aims to explore the nutritional and functional properties of taioba (Xanthosoma sagittifolium), a plant with edible leaves and tubers, and to investigate its potential for industrial-scale application as a source of starch. A systematic review was carried out and meta-analysis following the PRISMA guidelines was conducted based on a random effects synthesis of multivariable-adjusted relative risks (RRs). The searches were carried out in seven search sources, among which were Web of Science, Elsevier's Science Direct, Wiley Online Library, Springer Nature, Taylor & Francis, Hindawi, Scielo, ACS-American Chemical Society, and Google Scholar. The systematic review was guided by a systematic review protocol based on the POT strategy (Population, Outcome, and Types of studies), adapted for use in this research. Mendeley was a resource used for organization, to manage references, and to exclude duplicates of studies selected for review. The findings revealed that taioba leaves are abundant in essential nutrients, proteins, vitamins, and minerals. Additionally, the tubers offer rich starch content along with vitamins and minerals like iron, potassium, and calcium, making them an ideal substitute for conventional sources on an industrial scale. This research highlights the significance of studying the functionalities, applicability, and integration of this PANC in our diets, while also emphasizing its capability as a substitute for traditional starch varieties. Moreover, exploiting this plant's potential adds value to Amazonian resources, reduces import costs, and diversifies resource utilization across multiple industrial sectors.

Characterization of Nano- and Microstructures of Native Potato Starch as Affected by Physical, Chemical, and Biological Treatments.

Modifying starch allows for improvements in its properties to enable improved uses in food matrices, bioplastics, and encapsulating agents. In this research, four varieties of native potato starch were modified by acid treatment, enzymatic treatment, and ethanol precipitation, and their physicochemical, structural, thermal, and techno-functional characteristics were analyzed. According to FT-IR analysis, no influence of the modified starches on the chemical groups was observed, and by scanning electron microscopy (SEM), spherical and oval shapes were observed in the acid and enzymatic treatments, with particle sizes between 27 and 36 μm. In particular, the ethanolic precipitation treatment yielded a different morphology with a particle size between 10.9 and 476.3 nm, resulting in a significant decrease in gelatinization temperature (DSC) and more pronounced crystallites (XRD). On the other hand, the enzymatic treatment showed higher values for z-potential (ζ), and the acid treatment showed lower mass loss (TGA). Acid and ethanolic treatments affected the dough properties compared to native starches. The techno-functional properties showed a decrease in the water absorption index, an increase in the water solubility index, and varied swelling power behaviors. In conclusion, the modification of potato starches through acid, enzymatic, and ethanolic precipitation treatments alters their physicochemical properties, such as swelling capacity, viscosity, and thermal stability. This in turn affects their molecular structure, modifying morphology and the ability to form gels, which expands their applications in the food industry to improve textures, stabilize emulsions, and thicken products. Furthermore, these modifications also open new opportunities for the development of bioplastics by improving the biodegradability and mechanical properties of starch-based plastic materials.

Structural and physicochemical properties of rice starch from a variety with high resistant starch and low amylose content.

Research on the physicochemical properties of rice-derived endo-sperm high resistant starch (RS) with low amylose content (AC) is limited. In this study, we evaluated the physicochemical characteristics of such a starch variety and revealed that the starch granules exhibit a smoother, more refined surface with distinct edges, increased compactness, higher order of surface, and fewer cavities compared to those of a low RS rice variety. The starch crystal was classified as an A-type, which may be connected to the high amylose-lipid complex content. The branched internal long chains (B2 + B3) were abundant, allowing for easy entanglement with other molecular chains and a compact structure. Differential scanning calorimetry revealed the need for high temperature and energy to disrupt the double helix structure within the crystallization region of starch. Furthermore, starch viscosity analysis revealed a high cold paste viscosity, consistency, and setback value, with recrystallization yielding a stable structure, increased viscosity, and enhanced hydrolysis resistance to enzymes.

Purple rice starch in wheat: Effect on retrogradation dependent on addition amount

While individual starch types may not possess the ideal gelatinization and retrogradation properties for specific applications, the amalgamation of multiple starch varieties might bestow desirable physicochemical properties upon resulting starch-based products. This study explored the impact of incorporating purple rice starch (PRS), as a novel starch variant (up to 15 % PRS), on the gelatinization and retrogradation (within 14 days) of regular wheat starch (WS). Rheological and texture assessments demonstrated that the introduction of PRS diminished the viscoelasticity and hardness of fresh WS paste. Additionally, in the case of retrograded WS pastes stored at 4 °C for 1–14 days, the incorporation of 10 % or 15 % PRS effectively retarded the reduction in transparency and significantly reduced hardness, retrogradation degree, the ratio of absorbance at 1047/1017 cm−1, and relative crystallinity. Notably, 10 % PRS results in a more pronounced effect. Conversely, 5 % PRS induced an opposing impact on retrograded WS post-storage. Moreover, scanning electron microscopy revealed that as the proportion of PRS increased, the microstructure of gelatinized WS-PRS closely resembled that of pure PRS. In conclusion, the diverse effects of varying PRS proportions on WS alter the texture and characteristics of starch-based foods, underscoring the potential of starch blending for improved applications.

Effect of Fermentation Time and Varietal Difference on the Pasting Properties and Bread‐Making Ability of Cassava Starch (Manihot esculenta)

AbstractThis research is to investigate the breadmaking ability of three cassava starch varieties (96/1414, TME15, and YARA) grown in Cameroon. To achieve this, starch samples from each variety are collected before and during fermentation to determine chemical, rheological, and bread‐making properties. They are analyzed for pH, titratable acidity (TTA), lactic acid (LA), specific volume (SPV), and pasting properties using known method; These parameters are used to perform a principal component analysis (PCA). The morphological characteristics are studied by scanning electron microscope (SEM). Result shows that, there is a decrease in pH (6.21–3.8) with an increase in TTA (0.34–7.05) and LA (0.15–6.46) with fermentation time. In parallel, a decrease of pasting properties and an increase in SPV (1.15–2.82 cm3 g−1) are observed. The PCA surrounds 96/1414 day 30, YARA day 30, and TME15 day 25 α 30 as the best samples, and the SEM shows a superficial degradation of the granules after fermentation. Thus, this study suggests that the optimal sour cassava starch for bread‐making can be obtained from 96/1414 day 30, TME15 day 25 α 30, and YARA day 30. The variety 96/1414 appears to have the best bread‐making ability while TME15 appears to be most suitable for short fermentation time.

Correlation between in vitro starch digestibility and starch structure/physicochemical properties in rice

Natural resistant starch (RS) in rice provides human health benefits, and its concentration in rice is influenced by the structure and physicochemical properties of starch. The native starch structures and physicochemical properties of three rice varieties, QR, BR58, and BR50, and their relationships to in vitro digestibility were studied. The starch granules in all three varieties were irregular or polyhedral in shape. There were a few oval granules and a few pinhole structures in QR, no oval granules but a higher number of pinholes in BR58, and no oval granules and pinholes in BR50. QR is a low-amylose (13.8 %), low-RS (0.2 %) variety. BR58 is a low-amylose (15.3 %), high-RS (6.5 %) variety. BR50 is a high-amylose (26.7 %), high-RS (8.3 %) variety. All three starches exhibited typical A-type diffraction patterns. Starch molecular weight, chain length distribution, starch branching degree, pasting capabilities, and thermal properties differed considerably between the rice starches. The RS contents of the rice starch varieties were positively correlated with AAC, Mw/Mn, Mz/Mn, peak 3, B, PTime, and Tp and negatively correlated with Mn, peak 2, DB, PV, and BD, according to Pearson's correlation analysis. These findings may be helpful for the breeding and development of high-RS rice varieties.

The important role of starch fine molecular structures in starch gelatinization property with addition of sugars/sugar alcohols

The relationship between the fine structure of starch and its gelatinization properties is not well studied, particularly in relation to the influence of sugar or sugar alcohol. In this study, seven starches with distinct molecular structures were investigated to determine how different sugars and sugar alcohols affect their gelatinization properties. The inclusion of sugars and sugar alcohols resulted in a significant elevation of starch gelatinization temperatures (∼ 8 °C), especially with sucrose, isomaltose and isomalt. Nevertheless, the influence of these sugars/ sugar alcohols on the gelatinization temperature range and enthalpy change varied depending on the particular starch varieties. According to the correlation analysis, sugars and sugar alcohols mainly exert their impact on the starch gelatinization temperature range and enthalpy change by possibly interacting with amylose chains possessing a degree of polymerization ranging from 100 to 1000 (p < 0.05) and inhibiting the amylose leaching during gelatinization. These findings help a better understanding of the complex relationship between starch fine structure and gelatinization properties under the influence of sugars and sugar alcohols.

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.

Structural, Thermal, Rheological, and Morphological Characterization of the Starches of Sweet and Bitter Native Potatoes Grown in the Andean Region.

This study aimed to extract and characterize the morphological, physicochemical, thermal, and rheological properties of the starches of native potatoes grown in the department of Puno. Among the varieties evaluated were sweet native potato varieties Imilla Negra (Solanum tuberosum spp. Andígena), Imilla Blanca (Solanum tuberosum spp. Andígena), Peruanita, Albina or Lomo (Solanum chaucha), and Sutamari, and the bitter potatoes Rucki or Luki (Solanum juzepczukii Buk), Locka (Solanum curtilobum), Piñaza (Solanum curtilobum), and Ocucuri (Sola-num curtilobum), acquired from the National Institute of Agrarian Innovation (INIA-Puno). The proximal composition, amylose content, and morphological, thermal, and rheological properties that SEM, DSC, and a rheometer determined, respectively, were evaluated, and the data obtained were statistically analyzed using a completely randomized design and then a comparison of means using Tukey's LSD test. The results show a significant difference in the proximal composition (p ≤ 0.05) concerning moisture content, proteins, fat, ash, and carbohydrates. Thus, the amylose content was also determined, ranging from 23.60 ± 0.10 to 30.33 ± 0.15%. The size morphology of the granules is 13.09-47.73 µm; for the thermal and rheological properties of the different varieties of potato starch, it is shown that the gelatinization temperature is in a range of 57 to 62 °C and, for enthalpy, between 3 and 5 J/g.

Effects of Starch Addition on KGM Sol's Pasting, Rheological Properties, and Gel Texture.

Konjac tofu is an irreversible gel formed by removing the acetyl group from konjac glucomannan (KGM) through alkaline heating. This type of food is low in calories, filling, and healthy, making it popular in the market. However, pure konjac tofu has a hard texture and lacks flavor when heated. To improve its taste and appearance, the effects of three varieties of native starch, including corn starch (CS), Canna edulis Ker starch (CKS), and potato starch (PS), on the formation of pasting and rheological properties of the KGM sol were investigated. Konjac tofu samples that incorporated different types and quantities of starch were prepared and analyzed in terms of structure, texture, dehydration, and flavor, with pure konjac tofu serving as a reference. The findings revealed that KGM mixed with a concentration of 4.2% CS, or 0.85% CKS, or 0.85% PS of the total mass produced a gel with the highest viscosity and a steady structure. Texture profile analysis indexes of these combinations were superior to pure KGM, and the konjac-starch tofu had a lamellar network structure. Thus, konjac tofu with the addition of starch has a higher quality texture, lower dehydration, and improved flavor compared to pure KGM gel.

Effect of microwave treatment on technological, physicochemical, rheological and microstructural properties of mango (Mangifera indica) kernel starch variety Tommy and Sugar

Mango is a tropical fruit used in various agricultural food products. The purpose of the research was to analyze the application of microwave treatment on the, technological, physicochemical, thermal, morphological, pasting, and rheological properties of mango kernel starch from the varieties Tommy and Sugar. The microwave treatment at 900 W and 1 min was evaluated. After microwave treatment, the water absorption capacity (WAC) and amylose content increased significantly, being the highest values for the microwave-modified starch of mango var Tommy (To-MW). The Fourier transform infrared (FT-IR) spectroscopy results show that microwave treatment does not modify the chemical structure of starch. The rheological behavior showed that microwave-modified starches have higher values of consistency index and yield stress than native starches. The pasting test showed that the microwave treatment did not modify the pasting temperature of the mango kernel starch, while the peak, setback, breakdown and final viscosity showed a significant increase. The results obtained show that the application of microwave treatment increases the rheological and pasting properties of mango kernel starches without modifying their chemical composition, which is of great interest for its application in the formulation of new products in the food industry.

Effect of processing conditions on the functional properties of starches during formulation of quick-cooking brown rice

The demand for ready-to-cook and nutritious products is on the rise due to the lifestyle becoming more hectic throughout the world. In this study, quick-cooking brown rice was formulated from four rice varieties. For each variety, the process was optimized by analyzing different combinations of soaking time (10, 20, and 30 min), drying time (20, 30, and 40 min), and drying temperature (60, 70, and 80 °C). Central composite design (CCD) was used to select the best combinations based on the least cooking time and moisture content within the range of 12–14%, and the same was different for each rice variety. To comprehend the effect of these processing conditions on rice, its main constituent i.e. starch, known to affect the palatability of rice cultivars was investigated. The starches were extracted from all the four quick-cooking brown rice samples and their properties were compared with respective native starches. Results obtained indicated that the treated starch samples from all varieties had better solubility and swelling behaviors. Treated starches also demonstrated higher retrogradation as compared to native starches. Untreated starches showed a well-defined polygonal structure of starch granules while treated starches showed distorted structures under scanning electron microscopy indicating their partial gelatinization. X-ray diffraction results indicated that in all the varieties of rice A-type starch was present, however, upon treatment diffraction peaks changed for all the varieties and the typical A-type structure of untreated starch shifted to CA-type starch structure. Readily digestible starches (RDS%) of all the treated starches increased while slowly digestible starches (SDS%) of all the treated starches decreased. Results indicated that both soaking time, drying time and drying temperature had significant effect on the physicochemical properties and digestibility of rice starches.

Analysis of changes in gel properties during retrogradation of four kinds of sorghum starch

SummaryIn this study, four kinds of sorghum starch gels containing different amylose were taken as the research objects and stored for 28 days. The parameter changes of gel properties during the retrogradation of different varieties of sorghum starches were observed using X‐ray diffraction, Low‐field nuclear magnetic resonance, textural, rheological and anti‐enzymatic hydrolysis capacity studies to construct kinetic models for the retrogradation. The results showed that the degree of retrogradation, crystallinity and anti‐enzymatic hydrolysis capacity of sorghum starch increased with the prolongation of storage time, and the crystal forms of H5 (Hongnuo No. 5 sorghum) and L13 (Longza No.13 sorghum) starch changed from type A to B. Among the four kinds of starch, L13 starch had the highest degree of retrogradation, and H5 starch had the strongest recrystallisation ability. The hardness of L13 retrograded starch gel grew fastest with increasing storage time, while the viscoelasticity of H1 (Hongnuo No.1 sorghum) retrograded starch showed a stable trend. Low‐field nuclear magnetic resonance was used to detect that the L1 (Longmiliang No.1 sorghum) retrograded starch gel had more free water. The crystallisation rate was positively correlated with hardness, resistant starch content and crystallinity and negatively correlated with springiness, gumminess and resilience.

Different starch varieties influence the complexing state and digestibility of the resulting starch-lipid complexes

In this study, we investigated the complexing state and digestibility of complexes formed between myristic acid (MA) and several varieties of starch (maize starch, MS; waxy maize starch, WS; high amylose maize starch, HMS; rice starch, RiS; cassava starch, CS; potato starch, PS). The resistant starch (RS) content, complexing index, and degree of the structural order of HMS-MA and MS-MA complexes were significantly higher (p < 0.05) than those of the other complexes. Notably, the RS increments of MS-MA complexes were the highest (14.10%). CS-MA, MS-MA and RiS-MA complexes showed better thermal stability of starch than the other complexes. The MA molecules were primarily physically embedded outside the helical structure of starch in WS-MA and PS-MA complexes. Additionally, CS-MA complexes possessed the highest relative number of physically embedded MA molecules. Moreover, the distribution of physically embedded MA molecules in WS-MA, CS-MA, and PS-MA complexes was more homogeneous than that in the other complexes. The weight-average molecular weight of amylose, average chain length of amylopectin side chains, and the proportion of chains with a degree of polymerization of 6–12 and 25–36 greatly affected their interactions with MA molecules. These results indicated that starch types substantially influenced the digestibility of the complexes, which was closely related to their complexing state and structural order.

PROXIMAL, THERMAL, AND STRUCTURAL CHARACTERIZATION OF STARCH EXTRACTED FROM TWO VARIETIES OF WHITE SORGHUM CULTIVATED IN MEXICO

Sorghum (Sorghum bicolor) is a starch source that may contain tannins in red varieties, so white grains are preferred as a better alternative. The hypothesis of this study was that white sorghum starch grown in Mexico has the necessary properties for industrial use. The objective was to evaluate the chemical, thermal and structural characteristics of starch extracted from white sorghum var. Mazatlan-16, and RB-Paloma. Protein, moisture, ash, fiber, fat, water absorption rate, and swelling capacity were evaluated. Thermal properties were determined by calorimetry and viscosity analysis; structural properties by Fourier transform infrared spectroscopy and X-ray diffraction. One-way analysis of variance and Student’s t-test (p ≤ 0.05) were performed. The starch extracted from Mazatlán-16 grain contained the highest moisture (5.47 %), protein (0.72 %) and crude fiber values, and no significant differences (p ≤ 0.05) were found for ash and fat content in both starch varieties. The water absorption rate and swelling power was higher for RB-Paloma variety starch (p ≤ 0.05). Regarding thermal properties, the maximum viscosity temperature was 80.55 and 89 °C for RB-Paloma and Mazatlan-16 starch, respectively; the peak gelatinization temperature was higher for Mazatlan-16 (72.28 °C) and showed differences (p ≤0.05) with RB-Paloma. Structural analysis revealed that the starches of both varieties correspond to the A-type crystalline pattern, with the presence of OH, CH in stretching, H2O and CH2 groups. The starches extracted from the two varieties showed properties suitable for use as a viable alternative in the food industry.

The Effect of Acetylation of Faro 40 Rice Starch for the Production of Pharmaceutical Grade Starch

Introduction: Nigerian FARO 40 rice starch has been underutilized due to low edible qualities. Therefore, chemical modification of this variety for pharmaceutical use was contemplated, as native starch has shown to be integrally unsuitable for pharmaceutical applications. The aim of this study was to chemically modify underutilized rice variety using standard methods for possible use as pharmaceutical grade starch.&#x0D; Methodology: Native and acetylated FARO rice starch physicochemical properties were analysed using standard methods. Scan electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analyser and Derivative Thermogravimetric analyser were done to determine the morphological properties of native and acetylated starch. The starch tablets comparative binding and disintegrant capacities were examined utilizing paracetamol as model sedate. Wet granulation strategy and direct compression were used to defined the paracetamol tablets from native starch and acetylated starch as binders. The tablet features such as smashing quality, friability, crumbling time and disintegration test were assessed utilizing friabilitor machine, deterioration machine and disintegration device.&#x0D; Results: The results showed significant decreased (P&lt;0.05) values in pH, moisture content, and gelatinization temperature for acetylated starch compared to the native starch. Significant increase observed in ash content, solubility, swelling capacity, browning temperature, charring temperature and amylose content of acetylated starch as compared to the native starch. Furthermore, significant changes were also observed in morphology of the acetylated starch compared to the native rice starch. The weight, crushing strength, friability, disintegration time and dissolution profile values for paracetamol tablets formulated with the acetylated starch were within the standard specified by British pharmacopeia and were significantly different from that of native starch (P&lt;0.05).&#x0D; Conclusion: In conclusion, the research reviewed significant changes in physicochemical and morphological properties of acetylated FARO 40 underutilized Nigerian rice starch variety which suggest to improve the quality of the starch for pharmaceutical usage.

Organic Pea Starches – I. Comprehensive Investigation of Morphological and Molecular Properties

AbstractThe comparatively high amylose (AM) content in native pea starch leads to a good functionality in food and non‐food products. Nevertheless, it has also been reported that pea starch tends to cause manufacturing problems more often than other starches. It has been suggested that this is due to substantial variation of the starch qualities originating from different pea starch varieties. Therefore, additional research which explores morphological, physicochemical, molecular, and techno‐/functional properties of starches from multiple pea varieties is necessary. Here, a large variety of pea starches are analyzed. The structure and size of the starch granules is studied using scanning electron microscopy (SEM), laser particle sizing (LPS), and image analysis of optical microscopy (IAOM). The morphological appearance and size do not differ significantly between the pea cultivars. The AM content is determined with two methods, both based on iodine interaction with the AM helix. The method suggested here (SEC‐prep) results in systematically higher AM content. This is due to better solubilization of the starch. Nevertheless, only small differences between the pea cultivars are observed. No differences in morphological appearance, particle size, and only minor differences in AM content, significant variations in the molar mass distribution of the total starch fraction (MwST) and of the AM fraction (MwAM) are found.

CmMYB44 might interact with CmAPS2-2 to regulate starch metabolism in oriental melon fruit

Sugar content is one of the determining factors for melon fruit maturity. Studies have shown that starch gradually degrades during fruit ripening, resulting in sugar accumulation. But the specific relationship between starch metabolism and sucrose accumulation was still unknown. Here, the starch and sugar contents, the activities of key enzymes and the expression patterns of genes related to starch-sucrose metabolism were determined in the fruit of high sugar and starch variety ‘HS’ and low sugar and starch variety ‘LW’. It was found that starch accumulated during fruit development process, and then degraded at 30 days after anthesis (DAA), which was synchronized with sucrose accumulation in ‘HS’ fruit, while starch and sucrose contents were always at a lower level during ‘LW’ fruit maturation. Furthermore, starch metabolism-related enzymes (Adenine dinucleotide phosphate -glucose pyrophosphorylase (AGPase), α-amylase (AMY), β-amylase (BMY)) and the key enzymes for sucrose accumulation (sucrose phosphate synthase (SPS) and sucrose synthase (SS)) were significantly increased at ripening stage of ‘HS’ fruit, and their activities were consistent with the expressions of CmAPS2-2, CmAMY2, CmBAM1, CmBAM9 and CmSPS1. However, the contents of starch and sucrose and the activities of AGPase and SPS in ‘LW’ fruit didn't change significantly. We discovered an R2R3-type MYB transcription factor, CmMYB44, screened from yeast one hybrid library, could directly bind to the promoter of CmAPS2-2 to inhibit its transcription. These results revealed that the targeted down-regulation of CmAPS2-2 by CmMYB44 might be involved in the starch accumulation process, which affect the flavor quality of oriental melon fruit.