Non-starch Components Research Articles

Effect of different milling methods on isolation of pinto bean starch, and the characteristics of the isolated starches

This study investigated the effects of various dry milling methods (blade mill (BLM), stone mill (SM), hammer mill (HM), and burr mill (BM)) at different milling severities on pinto bean flour properties, influencing the starch isolation process and isolated starch characteristics.BLM and HM produced fine flours (<180 μm) with lower starch damage (<1 %) compared to SM and BM. The starch isolation yield and efficiency increased with a reduction in flour particle size. The highest isolation yield (38 %) and efficiency (85 %) were observed from flours of BLM at 5 min.The milling-induced changes in the starch properties of the flour also altered the characteristics of starch isolated from the flour. The gelatinization and pasting properties of flour were affected by the presence of non-starch components, and starch damage while in isolated starch, they were affected only by starch damage that occurred during milling. Both the flour and isolated starch exhibited changes in crystallinity based on particle size. The water and oil holding capacities were not significantly affected by milling.

Study on the Mechanism of Effect of Protein on Starch Digestibility in Fermented Barley.

Previous studies have shown that fermented barley has a lower digestion rate. However, it remains unclear whether the antidigestibility of starch in fermented barley is affected by other nonstarch components. In this paper, the removal of protein, lipid, and β-glucan improved the hydrolysis rate of starch and the protein showed the greatest effect. Subsequently, the inhibitory mechanism of protein on starch digestion was elucidated from the perspective of starch physicochemical properties and structural changes. The removal of protein increased the swelling power of starch from 10.09 to 11.14%. The short-range molecular ordered structure and the helical structure content decreased. The removal of protein reduced the coating and particle size of the starch particles, making the Maltese cross more dispersed. In summary, protein in fermented barley enhanced the ordered structure of starch by forming a physical barrier around starch and prevented the expansion of starch, which inhibited the hydrolysis of starch.

The multifactorial phenomenon of enzymatic hydrolysis resistance in unripe banana flour and its starch: A concise review.

Unripe banana flour starch possesses a high degree of resistance to enzymatic hydrolysis, a unique and desirable property that could be exploited in the development of functional food products to regulate blood sugar levels and promote digestive health. However, due to a multifactorial phenomenon in the banana flour matrix-from the molecular to the micro level-there is no consensus regarding the complex mechanisms behind the slow enzymatic hydrolysis of unripe banana flour starch. This work therefore explores factors that influence the enzymatic hydrolysis resistance of raw and modified banana flour and its starch including the proportion and distribution of the amorphous and crystalline phases of the starch granules; granule morphology; amylose-amylopectin ratio; as well as the presence of nonstarch components such as proteins, lipids, and phenolic compounds. Our findings revealed that the relative contributions of these factors to banana starch hydrolytic resistance are apparently dependent on the native or processed state of the starch as well as the cultivar type. The interrelatability of these factors in ensuring amylolytic resistance of unripe banana flour starch was further highlighted as another reason for the multifactorial phenomenon. Knowledge of these factors and their contributions to enzymatic hydrolysis resistance individually and interconnectedly will provide insights into enhanced ways of extraction, processing, and utilization of unripe banana flour and its starch.

Isolated cassava cells: Comparison of structure and physicochemical properties with starch and whole flour

Individual cells are the smallest units of the plant tissue structure, and their structure and physicochemical properties are essential for whole food processing. In this study, cassava cells were isolated using acid-alkali, hydrothermal, and pectinase methods, and the differences in microstructure and physicochemical properties among the cells, starch, and whole flour were investigated. Cassava cells isolated using pectinase showed intact individual cells with a higher isolation rate and less damage to the cell wall structure and intracellular composition. The presence of cell walls in intact individual cells inhibited the swelling and leaching of starch, resulting in a lower peak viscosity and higher gelatinization temperature than those of starch. The intact cell structure and non-starch composition enhanced the shear resistance of the gels in the sample. Heat treatment led to the gelatinization of intracellular starch and increased the permeability of the cell wall, destroying the physical barrier function of the cell wall; however, the compact cell matrix and non-starch components can inhibit starch hydrolysis. This study suggests that cells isolated using pectinase can be used to investigate the effect of cell walls on the functional properties of intracellular starch in cassava. The isolated cells provide new insights into the cassava industry.

Evaluación de las propiedades proximales, estructurales, morfológicas fisicoquímicas y de digestibilidad in vitro en mezclas de harinas de ñame y batata

Yam (Dioscorea spp.) and sweet potato (Ipomeas batata) flours must be treated through modification processes because they have limitations in their physicochemical and structural properties for use in agri-food matrices. This study aimed to evaluate the effect of different proportions of flours on the proximate, structural, morphological, physicochemical, pasting, and in vitro digestibility properties of yam and sweet potato flour blends. Flours were obtained by drying the tubers with hot air at 55 °C, and mixtures were prepared at 25:75, 50:50, and 75:25 w/w sweet potato and yam flour proportions, respectively. The yam starch granules were spherical, oval, irregular, and larger than those of sweet potatoes, which are ovoid and flared. Furthermore, yam and sweet potato granules presented with type-B and type-A diffraction patterns, respectively, which, together with the starch content, amylose, non-starch components, and their molecular interactions, influenced the decrease in the molecular order and degree of crystallinity of the flour blends, without altering the morphological characteristics of the simple flours. Additive and non-additive effects were observed on flour blends’ swelling power and water absorption capacity. Likewise, breakdown and setback viscosity increased, which decreased thermal stability, increased the tendency to retrogradation, and elevated the fractions of rapidly digestible starch and resistant starch. These results suggest the high potential of flour blends in preparing baked products from the Caribbean Region, such as white bread, cookies, and cakes.

158 Nutrient digestibility in growing pigs fed a corn distiller’s dried grains with soluble-based diet with multi-enzyme supplementation

Abstract Dietary enzyme supplementation may enhance the digestibility and utilization of non-starch components in fiber-rich feedtuffs which are increasingly used in swine diets. A xylanase/cellulase enzyme product (ENZ) was previously shown to increase the digestibility of nutrients and energy in growing pigs fed a corn-SBM diet with 30% corn dried distiller’s grains with solubles (cDDGS). To better elucidate the effects of ENZ on these components, further analysis was conducted on the fiber, non-starch polysaccharide, and ash components. A total of 12 ileal-cannulated pigs [initial body weight (BW) = 31.7 kg ± 3.04] were housed in individual metabolic crates for 21 d (period 1) and subsequently transferred to individual floor pens for an additional 28 d (period 2). These animals were assigned to 2 diets (n = 6) in a completely randomized design (CRD). The diets contained the main ingredients corn, soybean meal and cDDGS (30%) without (CON) or with ENZ supplementation. The inclusion rate of the ENZ (proprietary xylanase/cellulase product, Kerry Inc.) was 200 g/ton. Feed was formulated to 1.15% SID lysine and met or exceeded nutrient requirements for growing pigs (NRC, 2012). The diets were fed to pigs at three times maintenance energy requirement based on BW, which was assessed at 2 wk intervals throughout the study. The diets contained 0.3% titanium dioxide as an indigestible marker. In period 1, pigs had 14 d of adaptation, followed by 4 d of fecal and urine collection using the total collection method and 2 d of ileal digesta collection. In period 2, pigs had 23 days of adaptation, followed by 2 d of fecal collection and 2 d of ileal digesta collection. Data were analyzed as a CRD, using pig as the experimental unit and enzyme supplementation as the main effect. The ATTD of total NSP and galactose tended to improve in both periods 1 and 2. As consistent responses were observed in periods 1 and 2 and the ENZ X period interaction was not significant, the data from these time periods were combined for analysis. ENZ supplementation improved (P &amp;lt; 0.05) the ATTD of total NSP and galactose. Also, ENZ tended to improve (P &amp;lt; 0.10) the ATTD of cellulose and glucose from NSP. ENZ addition also increased the ATTD of calcium (P &amp;lt; 0.05) and tended to increase the ATTD of phosphorus (P &amp;lt; 0.10). In conclusion, supplementation of a corn-SBM-30% cDDGS diet with a multi-carbohydrase containing cellulase increased the ATTD of fiber, NSP and calcium in growing pigs. Novel enzymes represent a useful strategy to better utilize the nutrients in lower energy feedstuffs in monogastric animals.

Interactions between partially gelatinized starch and nonstarch components in potato flour and their performance in emulsification

To develop natural complex materials as starch-dominated emulsifiers, pregelatinization was conducted on potato flour. The effects of gelatinization degrees (GDs, 0 %–50 %) on the structural characteristics, physicochemical properties, and emulsifying potentials of potato flour were investigated. Increasing GD of potato flour promoted protein aggregation on starch granules surfaces and transformed starch semicrystalline structures into melted networks. The emulsion stabilized with 50 % GD potato flour exhibited excellent storage stability (7 d) and gel-like behavior. With increasing GD from 0 to 50 %, the respective apparent viscosities and elastic moduli of emulsion increased from 21.4 Pa to 1126.7 Pa, and from 0.133 Pa·s to 1176.6 Pa·s, promoting the formation of a stable network structure in the emulsion. Fourier transform infrared spectra from emulsions with a continuous phase of >20 % GD displayed a new peak around 1740 cm−1, suggesting improved covalent interactions between droplets, thereby facilitating emulsion stability. Confocal laser scanning microscopy images indicated that droplets could be anchored in the melted networks and broken starch granules, inhibiting droplets coalescence. These results suggest that pregelatinization is a viable strategy for customizing natural starch-dominated emulsions.

Ultrasound-assisted annealing treatment to improve physicochemical and digestive properties of banana flour.

Banana flour can provide a solution to people with gluten intolerance, as it is gluten-free. Native banana flour may have limited functionality in certain applications. In this study, banana flour was modified by ultrasonic (US) and annealing (ANN) treatments at four incubation time spans, namely 12, 24, 36 and 72 h, separately or combined sequentially (US-ANN) to enhance the physicochemical and digestive properties. US led to exposed granular surfaces and damaged non-starch components. Both treatments, at extended incubation time, increased crystallinity, resulting in a narrower starch gelatinization temperature range. The swelling power was significantly lower for ANN and US-ANN compared to US alone, providing a delay of gelatinization temperature. However, none of the treatments affected the gelatinization enthalpy. Furthermore, US increased peak viscosity, breakdown, final viscosity and setback whereas the opposite results were obtained for ANN and US-ANN. Additionally, US prior to ANN significantly increased the resistant starch (RS) content for annealing times over 24 h, especially for the US-ANN treatment for 72 h, which provided the highest RS content (49.3%) compared to ANN treatment for 72 h (44.0%) and native flour (36.3%). US prior to ANN treatment offers an alternative method to improve the functional and digestive properties of banana flour, extending the range of applications. © 2024 Society of Chemical Industry.

The combined actions of the granule surface barrier and multiscale structural evolution of starch on in vitro digestion of oat flour

The digestive properties of oat-based food have garnered considerable interest. This study aimed to explore the internal and external factors contributing to different digestion properties of oat flour under actual processing conditions. Analysis of the ordered structure of oat starch revealed that an increase in gelatinization moisture to 60 % led to a decrease in crystallinity, R1047/1022 value, and helical structures content to 0, 0.48 %, and 1.45 %, respectively. Even when the crystal structure was completely destroyed, the short-range structure retained a certain degree of order. Surface structure observations of starch granules and penetration experiments with amylase-sized polysaccharide fluorescence probes indicated that non-starch components and small pores effectively hindered the diffusion of the probes but low-moisture (20 %) gelatinization substantially damaged this barrier. Furthermore, investigations into starch digestibility and starch molecular structure revealed that the ordered structure remaining inside the starch after high gelatinization delayed the digestion rate (0.028 min−1) and did not increase the content of resistant starch (7.10 %). It was concluded that the surface structure and non-starch components of starch granules limited the extent of starch digestion, whereas the spatial barrier of the residual ordered structure affected the starch digestion rate.

The preliminary study of applications waste banana peel and egg shell filler as agricultural waste for paper applications

This research investigates the use of banana peel ingredients that are removed from leftover banana peels to make paper. The paper was prepared by using hand sheet press machine. The study explores this non- starch elements’ potential by thoroughly examining their characteristics in an oven setting. Despite being seen as agricultural waste; banana peels include cellulose-rich components that make them a promising resource for the manufacturing of sustainable paper. The investigation uses oven-based procedures to extract and analyse non-starch components, looking at their structural and thermal characteristics. The results show that the waste banana peel with 5g of egg shell showed the highest of tensile strength which is 0.614 MPa followed by 2g of egg shell added. The combinations of waste of waste carbon box (WCB), waste banana peel and egg shell filler as paper gives the maximum loads, deflections and tensile strength. By reusing agricultural by-products for useful purposes, this project aims to support the development of environmentally responsible methods in the paper sector via a comprehensive assessment of oven qualities.

Effect of non-starch components on the structural properties, physicochemical properties and in vitro digestibility of waxy highland barley starch

Highland barley (HB) endosperm with an amylose content of 0–10 % is called waxy HB (WHB). WHB is a naturally slow-digesting grain, and the interaction between its endogenous non-starch composition and the WHB starch (WHBS) has an important effect on starch digestion. This paper focuses on the mechanisms by which the components of β-glucan, proteins and lipids affect the molecular, granular, crystalline structure and digestive properties of WHBS. After eliminating the main nutrients except for starch, the estimated glycemic index (eGI) of the samples rose from 62.56 % to 92.93 %, and the rapidly digested starch content increased from 60.81 % to 98.56 %, respectively. The resistant starch (RS) content, in contrast, dropped from 38.61 % to 0.13 %. Comparatively to lipids, β-glucan and protein contributed more to the rise in eGI and decline in RS content. The crystalline characteristics of starch were enhanced in the decomposed samples. The samples' gelatinization properties improved, as did the order of the starch molecules. Protein and β-glucan form a dense matrix on the surface of WHBS particles to inhibit WHBS digestion. In summary, this study revealed the mechanism influencing the digestibility of WHBS from the perspective of endogenous non-starch composition and provided a theoretical basis to develop slow-digesting foods.

306 Nutrient Digestibility and Dietary Energy Values in Growing Pigs Fed a Corn Distillers Dried Grains with Soluble (Cddgs)-Based Diet with Multi-Enzyme Supplementation

Abstract Dietary enzyme supplementation may enhance the digestibility and utilization of non-starch components of the diet by pigs. This study was conducted to evaluate the efficacy of a multi-carbohydrase enzyme (ENZ) in growing pigs for apparent ileal digestibility (AID) of amino acids (AA), apparent total tract digestibility (ATTD) of nutrients and energy values in a corn distillers dried grains with solubles (cDDGS)-based diet. A total of 12 ileal-cannulated pigs [initial body weight (BW) = 31.7 kg ± 3.04] were housed in individual metabolic crates for 21 days (Period 1) and subsequently transferred to individual floor pens for additional 28 days (Period 2). These animals were assigned to 2 diets (n = 6) in a completely randomized design (CRD). The diets were formulated on corn, soybean meal and cDDGS (30%) without (CON) or with ENZ supplementation. The ENZ (Proprietary xylanase/cellulase product, Kerry Inc.) was included in the diets at 200 g/tonne. Feeds were formulated to 1.15% SID lysine and met or exceeded nutrient requirements for growing pigs (NRC, 2012). Pigs were fed diets at three times maintenance energy requirement based on BW, which was assessed at every 2 weeks intervals throughout the study, Titanium dioxide was added to the diets as an indigestible marker. In period 1, pigs had 14 d of adaptation, followed by 4 d fecal and urine using the total collection method and 2 d ileal digesta collection. In period 2, pigs had 23 days adaptation, followed by 2 d fecal collection and 2 d illeal digesta collection. The AID of AA and gross energy (GE) and ATTD of nutrients and GE were calculated by an index method. Data were analyzed as a CRD, using pig as the experimental unit and enzyme supplementation as the main effect. Overall, average daily gain and gain:feed ratio of pigs were 857 and 918 g/d and 0.52 and 0.54 for CON and ENZ, respectively (P &amp;gt; 0.05). In period 1, ENZ supplementation improved (P &amp;lt; 0.05) the ATTD of dry matter (DM), ash, organic matter (OM), neutral detergent fiber (NDF), and GE by 4.4%, 26.8%, 2.8%, 11.3%, and 3.6%, respectively. Also, ENZ tended to improve (P &amp;lt; 0.10) the ATTD of crude protein (CP) by 7.4% and AID of threonine, CP, and GE by 6.6%, 7.6%, and 13.7%, respectively. In period 2, ENZ improved (P &amp;lt; 0.05) the ATTD of DM, ash, OM, CP, NDF, and GE by 5%, 30.1%, 3.4%, 4.1%, 19.6%, and 4.2%, respectively. similarly, EMZ improved (P &amp;lt; 0.05) the AID of threonine, CP, and GE by 4.2%, 6.0%, and 6.4%, respectively. In conclusion, multi-carbohydrase supplementation in a corn-SBM diet with 30% cDDGS increased the digestibility of nutrients and energy in growing pigs and may represent a useful strategy to optimize the utilization of such raw material.

Insight into the dynamic molecular mechanism underlying the endogenous polyphenols inhibiting the in vitro starch digestion of highland barley noodles

Highland barley is a type of grain with slow-digesting characteristics. It is worth exploring the impact of non-starch components on starch digestion. In this study, four varieties of highland barley were used to investigate the impacts of endogenous polyphenols (EP) on the relationship between starch structure, physicochemical properties, and the time course digestibility of highland barley noodles. The results showed that EP removal decreased the proportion of long-chain amylopectin and disrupted the crystalline structure, while increasing the short-range ordered structure in the residue. Significant correlations indicated that these structural changes make starch more susceptible to thermal degradation and digestion, causing a 12.60%-52.00% increase in rapidly digestible starch (RDS) and a 12.70%-25.22% decrease in resistant starch (RS). These results revealed the internal factors that affect the slow digestion characteristics of highland barley noodles from the perspective of EP and provide important reference values for a slow digestion diet.

Effect of particle size classification on properties of flour from jack bean: An under-utilized high protein legumes

Jack bean (Canavalia ensiformis L., DC) is one of the most under-utilized crops in the food industry. This study explored the chemical and functional properties of whole seed flour (WJB) and kernel flour (KJB). The impact of dry sieving for particle size classification on WJB and KJB flours was also investigated. Unclassified WJB and KJB exhibit protein contents of 30.7 ± 0.2 g/100 g and 35.2 ± 0.1 g/100 g1, respectively, along with a resistant starch content of 5.8 ± 0.1 g/100 g and 4.6 ± 0.1 g/100 g, respectively. The protein in jack bean flour compares favorably with beef and egg protein in terms of amino acid composition. The crystallinity, swelling power, solubility, and pasting properties of WJB and KJB flours tended to increase with particle size reduction, corresponding with an increase in starch content. This study highlights that dry sieving is an effective technique for diversifying the chemical and functional qualities of jack bean flour. Smaller sieve apertures selectively remove non-starch components, allowing for tailored flour properties.

The effect of heat-moisture treatment changed the binding of starch, protein and lipid in rice flour to affect its hierarchical structure and physicochemical properties.

This study investigated the effect of removing proteins, lipids and starch on the structure, physicochemical properties and digestion properties of rice flour (with 30% moisture) treated with heat moisture treatment (HMT). According to the results, HMT caused the adhesion and agglomeration of the rice flour, promoted the binding between starch, protein and lipid molecular chains and led to the formation of complexes (especially starch-lipid complexes), which hindered the removal of non-starch components. Compared to the untreated rice flour, the HMT treated lipid-removal rice flour had small changes in their crystallinity, gelatinization temperature and viscosity property. After removing protein, the crystallinity, peak viscosity, final viscosity, breakdown and starch digestibility were sharply increased. In particular, the peak viscosity increased from 811 cP to 1746 cP and the enthalpy change increased from 5.33J/g to 10.18J/g. These findings are helpful in understanding the contribution of removing endogenous proteins and lipids to the physicochemical changes of HMT treated rice flour during its heating process and thus can be helpful in controlling the quality of rice flour through HMT.

Interactions between Fuzi (Aconiti Lateralis Radix Preparata) total alkaloids and Fuzi starch: Structural, physicochemical, and rheological properties

Interactions between starch and nonstarch components have attracted enormous attention, but limited information is available on the interactions between starch and alkaloids. To elucidate the interaction mechanism between Fuzi total alkaloids (FTA) and Fuzi starch, Fuzi starch-FTA complexes with different FTA concentrations (0, 1, 3, and 5 g/100 g Fuzi starch) were prepared, and their structural characteristics, physicochemical properties, and rheological behaviors were investigated. Fourier transform infrared spectroscopy results demonstrated that FTA interact with starch via hydrogen bonding. Moreover, the addition of FTA increased the formation of a short-range ordered structure. X-ray diffraction results confirmed the existence of hydrogen bonding and suggested that the relative crystallinity of Fuzi starch decreases with the presence of FTA. Furthermore, FTA elevated the solubility of Fuzi starch and reduced its swelling power, coagulability, gelatinization temperature, and enthalpy change. Based on rheological analyses, Fuzi starch-FTA complexes exhibited non-Newtonian fluid properties and a typically weak gel rheological behavior. After adding FTA, the shear stress, viscosity, and storage/loss modulus of Fuzi starch decreased. Overall, our work enriches the theory of starch-alkaloid interactions and provides data to support investigation into the future applications of Fuzi starch.

Intrinsic and extrinsic factors drive differences in the gelatinisation behaviour of barley and malt starch

We studied the impact of malting on barley starch gelatinisation properties and whether observed differences are due to changes in extrinsic or intrinsic factors. We isolated the total starch and large and small starch granules fractions from barley and malt samples and subjected them to DSC. The peak gelatinisation temperature for malt starch was, on average, 1.2 °C higher than for barley starch. The malting process and endosperm breakdown products were each responsible for half of this difference. The presence of water-extractable, non-starch components (sugars, minerals, protein and starch hydrolysis products,…) increased the intrinsic starch gelatinisation temperatures by 2.2–4.7 °C for barley and 3.6–5.3 °C for malt. The small starch granule fractions from barley had a 3.1 °C higher peak gelatinisation temperature than large granule fractions. No effect of malting was observed here. These findings indicate that matrix effects and starch granule size must be considered when addressing starch conversion during brewing.

Nonlinear rheological properties of Chinese cold skin noodle (liangpi) and wheat starch gels by large amplitude oscillatory shear (LAOS)

The recipe secret of making Chinese cuisine cold skin noodles (liangpi) with wheat flour was revealed by linear and nonlinear rheological characterization of wheat starch gel systems, which were made from different concentrations of liangpi slurry (LPS) and wheat starch slurry (WSS). The peak viscosity of LPS was suppressed at low concentrations and significantly higher than that of WSS at high concentrations. The G′ and G″ of LPS gels were higher than that of WSS gels under the same concentration, while the tanδ values were low in LPS gels and exhibited relatively greater mobility. This difference in LPS may be related to the non-starch components in it. The two starch gel systems were further characterized by the large amplitude oscillatory shear (LAOS) test. Lissajous curves showed that LPS gels follow a highly different elastic and viscous evolution than WSS gels during large deformation cycles. This was also evidenced by more pronounced strain stiffening and shear thickening trends of LPS gels and the larger I3/I1 values. The introduction of non-starch components was responsible for the significant changes in the properties of starch gels, and the LAOS method helped us to better understand these differences.

Differences in the desizability of starches and the mechanism of inhibiting desizing

The desizing efficiencies of starches are different. However, the reasons and mechanism for this appearance are still unclear. Therefore, desizing efficiencies of starches were measured, and the reasons for their difference were analyzed. Swelling ability and degree of crystallinity of starch films were tested to conform to the relation with desizing. The size residue on the desized yarns was collected to detect the difference in the proportion of nonstarch components and the structure of hydrolyzed starch. In addition, correlation analyses were conducted between the factors affecting hydrolysis and desizing efficiency. It was found that corn starch has the lowest desizing efficiency, and the efficiency of cassava starch was the highest. The largest proportion of protein was the main reason for inhibiting the desizing. Furthermore, a higher proportion of lipid and the lower swelling ability of starch film could also be an obstacle to desizing. Removing the nonstarch components and improving the swelling ability of film may be effective methods to improve the desizing efficiency of starch.

Effect of Starch Chain Structure and Non‐Starch Components on the Hydrolysis of Starch by α‐Amylase

AbstractThere are differences in enzymatic hydrolysis of starch slurries determined by the starch‐iodine method, but the reason for this phenomenon is not clear. In this study, corn, cassava, and potato starches that are commonly used in warp sizing as the research object, separating amylose and amylopectin, removing lipids or lipids, and proteins in starch, to explore the effect of starch molecular structure and nonstarch components on the hydrolysis of starch catalyzed by α‐amylase. The results show that about 10% of the corn starch is resistant to hydrolysis, much more than cassava and potato starches. Differences in amylose structure have no significant effect on hydrolysis, but the degree of hydrolysis of corn amylopectin is significantly lower than that of the amylopectins in cassava and potato starch, because of its higher molecular density. Lipid removal has a slight effect on the hydrolysis, but protein removal obviously improves the hydrolysis of corn starch, with only ∼2% of resistant starch remaining. Endogenous protein has the most excellent inhibitory effect on the hydrolysis of starch slurry, followed by lipids and the higher molecular density of amylopectin.