Article

Effect of Xanthan Gum on Blood Sugar Level after Cooked Rice Consumption

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Abstract

This study investigated how different combinations of xanthan gum and rice affect blood sugar levels after rice consumption. The addition of ≥1.0% xanthan gum during rice cooking (XGP-added groups) suppressed blood sugar levels 15 and 30 min after rice consumption. The glycemic index (GI) was significantly lower in all XGP-added groups than in the standard rice group. In all groups where xanthan gum sol was mixed with the cooked rice (XGS-mixed groups), blood sugar levels at 15 – 60 min were significantly lower and GI was lower than those in the standard rice group. Suppression of blood sugar levels by xanthan gum sol was more effective when consumed concurrently with rice than when consumed before or after consumption. The above findings revealed that blood sugar levels after rice consumption are suppressed most effectively when the rice is coated in xanthan gum sol.

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... Figure 2 summarizes the process of literature search, identification, and screening, based on the PRISMA flow chart. Of these 14 papers, 4 investigated pullulan [22][23][24][25], 7 investigated xanthan gum [26][27][28][29][30][31][32] and three investigated dextran [33][34][35]. ...
... In Fuwa et al. [30], the xanthan was mixed into the rice meal and added directly during the rice cooking. The concentrations used were 0, 0.5, 1.0, and 2.5% of raw rice weight. ...
... Adding xanthan gum to the muffins reduced fasting glucose significantly [26]. Additionally, [30] added xanthan gum to rice cooking, resulting in a significant reduction in blood glucose responses. This is an interesting and relatively simple intervention to modulate glucose responses effectively by coating a typically high glycemic index staple food (rice) with a food hydrocolloid and warrants further investigation. ...
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Diabetes mellitus is a chronic condition characterized by increased blood glucose levels from dysfunctional carbohydrate metabolism. Dietary intervention can help to prevent and manage the disease. Food hydrocolloids have been shown to have favorable properties in relation to glycaemic regulation. However, the use of food hydrocolloids of bacterial origin to modulate glucose responses is much less explored than other types of hydrocolloids. We, therefore, carried out the first review examining the impact of intake of food hydrocolloids of bacterial origin (as a direct supplement or incorporated into foods) on glycemic response in humans. Fourteen studies met the inclusion criteria. They used either xanthan gum, pullulan, or dextran as interventions. There was a wide variation in the amount of hydrocolloid supplementation provided and methods of preparation. Postprandial blood glucose responses were reduced in half of the studies, particularly at higher intake levels and longer chain hydrocolloids. When xanthan gum was added to the cooking process of muffins and rice, a significant reduction in postprandial blood glucose was observed. The use of these hydrocolloids is potentially effective though more research is needed in this area.
... This can be linked with turning fluids in gastrointestinal tract (GIT) into a viscous and gel-like substance. As a consequence, the rate of digestion and glucose uptake in bloodstream is affected, thereby prevents blood sugar spikes after eating (Fuwa, Nakanishi, & Moritaka, 2016;Tanaka, Nishikawa, Kure, Tsuda, & Hosokawa, 2018). Considerable effort has been expended as to understand the processes and mechanism of the xanthan-induced thickening that leads to low solubility or high viscosity. ...
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Texture perception, astringency phenomena, and oral sensation are directly influenced by molecular interactions. This study systematically characterizes the diverse array of molecular interactions in a binary model system comprising of mucin, the major viscosity enhancer of biological fluids, and xanthan gum, a major food hydrocolloid, at a pH range of 1 to 7. Coexistence of xanthan gum and mucin at 1:2 ratio (w/w) under acidic pH results in phase separation, as evidenced by the formation of visible aggregates. ζ-Potential data rule out any relevant electrostatic interactions. Fluorimetry analysis points to the existence of two distant binding regimes of mucin, manifesting at low (y1) and high (y2) xanthan gum concentrations, corroborating a pH-independent two-step binding mechanism. Enthalpy-dominated (ΔH° < 0) interaction occur at pH 7, whilst, entropy-driven (ΔS° > 0) interactions (classical hydrophobic forces) stabilize both transient and static complexes at pH 3. Both macromolecules interact spontaneously (ΔG° < 0) at the two pH values. Based on rheological data, the macromolecular interaction proves to be less dependent on the mucin to xanthan gum weight ratios. Nevertheless, the partial substitution of mucin with xanthan gum leads to enhanced viscoelasticity (G' > G") and increased relaxation times (λ). Furthermore, the xanthan gum inclusion in mucin systems at a 5:5 (w/w) ratio elevates the apparent viscosity (η) ≥ 45-fold (21.59 Pa.s) and ≥ 70-fold (33.52 Pa.s) in comparison with mucin (0.46 − 0.48 Pa.s) at pH 3 and pH 7, respectively. The findings of this study highlight the physicochemical basis of designing dysphagia diets, modulating food functionality, and tailoring the organoleptic properties of food systems.
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The semi-solidified nutrition supplemented with soluble dietary fiber, xanthan gum (XG), inhibited postprandial glycemia in rats. The purpose of the present study is to examine whether XG exerts the same effects in humans. Subjects fasted for 12 h and then ingested the enteral nutrient, Meibalance with or without XG at 9 AM. Blood glucose levels were measured 0, 20, 40, 60, and 120 min after its ingestion. Postprandial blood glucose levels were lower in the XG group than in the control group. At 20 min, postprandial blood glucose levels were significantly lower in the XG group (84±5.3 mg/dL) than in the control group (107±7.8 mg/dL) (p<0.05). A significant difference was also observed in ΔAUC between the two groups. These results demonstrate that XG exerts inhibitory effects on glucose excursion in humans.
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In an attempt to control the blood sugar increase that occurs after consuming cooked rice, we assessed the enthalpy and sensory and textural properties of κ-carrageenan-supplemented rice, and measured its effect on blood glucose in 13 fasting subjects. Samples were prepared by adding κ-carrageenan during cooking, (CP) or in gel form alone (CG) or in combination with CaCl2 (CG-CaCl2) to precooked rice. Subjects who consumed greater than 1.0% CP hadsignificantly lower blood sugar levels after 15 and30 min comparedwith subjects who consumed standard cooked rice (control). blood sugar levels of 1.6% CP were only lower than in control after 45 min. The glycemic index (GI) of rice supplemented with greater than 1.0% CP was significantly lower than that of control, and glucose release decreased with CP supplementation greater than 0.5%. Glucose release andGI did not significantly differ between CG-CaCl2 and control groups. Subjective and objective measures of texture property suggested that hardness significantly increased in rice supplemented with 0.5% CP.
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The consumption of soluble dietary fibres is associated with a variety of physiological responses, one of which is their ability to modulate postprandial glycaemic response due to increasing digesta viscosity. The effects that the different digestive processes in the stomach and small intestine have on the thickening ability of six soluble fibres were investigated in this study. Moreover, the ability of these fibres to resist loss of viscosity following two-stage in vitro digestion, simulating gastric and small intestinal phases, was analyzed. In a second set of experiments, protein and starch were included to simulate a food model, which allowed for glucose release. The second stage was carried out inside a dialysis system. The primary determinant of starch digestibility was the concentration of glucose in the dialysate over a 3 h period. Irrespective of the concentration level or simulated condition, xanthan gum (XG) retained viscosity more than all other fibre types (p < 0.05). XG reduced glucose concentrations in the dialysate in comparison to the control and the others fibres employed in this study (p < 0.05). The ability of XG to attenuate glucose diffusion means that it may be a target for future studies, both in vitro and in vivo, which seek to analyze food ingredients as aids in effectively mediating the postprandial glycaemic response in humans.
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繊維質とは,自然に放置しても分解されにくく,動物によっても消化されにくい成分のことを指す.本来,ヒトの消化酵素で消化されない繊維質は,生理的意義が低い非栄養素とされてきたが,難消化性の繊維質はヒトの健康維持に重要な役割を果たすことが次第に知られるようになった.食物繊維とは多糖類のひとつであるが,日本食品標準成分表2010では「ヒトの消化酵素で消化されない食品中の難消化性成分の総体」と定義されている.ヒトの炭水化物消化酵素であるアミラーゼは,デンプンを構成している糖分子のα結合を分解できるが,食物繊維を形成しているβ結合を分解する能力がない.従来,食物繊維はエネルギー源にならないと考えられていたが,実際は,消化されない食物繊維の一部が腸内細菌により発酵分解されて短鎖脂肪酸とガスになるため,エネルギー量はゼロにはならない.また,食物繊維はタンパク質,脂質,炭水化物(糖質),ビタミン,ミネラルに次いで,ヒトに不可欠な第六の栄養素として数えられるようになっている.食物繊維は水に溶けない不溶性(water-insoluble dietary fiber ; IDF)と水に溶ける水溶性(water-soluble dietary fiber ; SDF)に大別される.一般的に食物繊維は,食物の咀嚼回数や消化液の分泌を増加させたり,便通や腸内環境を改善したりするが,不溶性と水溶性で異なる生理作用もある.不溶性食物繊維は保水性が良く,便量の増加や腸の蠕動運動の促進,脂肪や胆汁酸,発がん物質等の吸着・排出作用がある.水溶性食物繊維は,糖の消化吸収を緩慢にして血糖値の急な上昇を抑える糖尿病予防効果,胆汁酸の再吸収を抑えてコレステロールの産生を減らす脂質異常症の抑制効果が期待できる.また,水分を吸収してゲル化するため,胃腸粘膜の保護や空腹感の抑制作用がある.不溶性食物繊維には植物体を構成するセルロース,ヘミセルロース,リグニン,エビやカニ類の外骨格成分であるキチン・キトサンがある.セルロースは植物の細胞壁の主成分で,野菜や穀類の外皮に多く含まれる.グルコースがβ-1,4結合により直鎖状に連なってリボン状に折り重なる構造をしているため,力学的に強固な物質である.ヘミセルロースも細胞壁を構成する不溶性食物繊維であるが,セルロースを構成するグルコースが他の糖で置換された多糖類である.糖分子の種類によって水溶性が異なり,マンナン(グルコマンナンとも呼ばれるコンニャクの成分.グルコースとマンノースがβ-1,4結合したもの),β-グルカン(キノコ類や酵母類に含まれる.グルコースがβ-1,3または-1,4結合したもの),キシラン(細胞壁の成分であるキシロースがβ-1,4結合したもの)等がある.リグニンは果物や野菜の茎,穀類の外皮に含まれる木質の繊維である.キチンはセルロースに構造が似ているが,N-アセチル-D-グルコサミンが連なるアミノ多糖であり,キトサンはキチンからアセチル基が除かれたD-グルコサミン単位からなるものである.水溶性食物繊維にはガム質,ペクチン,藻類多糖類等が分類される.ガム質は植物の分泌液や種子に含まれている粘質物で,代表的なものにグアー豆に含まれるグアーガム(マンノース2分子に1分子のガラクトースの側鎖をもつ多糖類)がある.ペクチンはガラクツロン酸がα-1,4結合した構造をしており,腸内細菌では分解できるがヒトの消化酵素では分解できない.果物類に多く含まれ,水分を吸収してゲル化する性質があり,砂糖と酸を加えて加熱調理するジャムやゼリーの製造に利用されている.藻類多糖類には渇藻類に多いアルギン酸,紅藻類に多いフコイダン,寒天の主成分であるアガロース等がある.この他に,トウモロコシを原料として人工的に合成されるポリデキストロースや難消化性デキストリンも食物繊維として使用されている.食物繊維の摂取目標量は,日本人の食事摂取基準(2010年版)によると,18歳以上では1日あたり男性19g以上,女性17g以上とされている.日本人の食物繊維摂取量は,食生活の欧米化や穀類,芋類,野菜類,豆類の摂取減少の影響を受けて第二次世界大戦後から年々減り続けており,実際の摂取量は若い世代を中心に目標量を満たさない状況が続いている.
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Potato starch(PS), guar gum(GG), xanthan gum(XG), and water(W)-added cooked rice were used to examine their effect on rice grain digestibility by blood sugar and glucose release values. Blood sugar level did not differ significantly between a sample of rice alone and sol-added samples after rice intake but was significantly lower with an XG-added sample than with PS-and W-added samples in 15 and 30 minutes. The XG-added sample yielded significantly lower glycemic index values than samples of rice alone and with PS andWadded did. Samples with XG added at 25 and 50 w/w% yielded significantly lower glucose release values than samples of rice alone and with PS, Wand GG added did. In a sensory evaluation, the XG-and GG-added samples scored significantly higher than the PSand W-added samples in the ease of swallowing as one piece and coherence of food mass. The above data indicate that GG addition is useful for chewing and swallowing safety and digestibility.
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Male Wistar rats, starved for 24 hours, were given a glucose solution with a stomach tube to provide 250 mg of glucose per 100 g of body weight. Blood samples were collected after intubation and blood glucose was measured. The time course of blood glucose concentration after an administration of glucose solution containing “kajime” powder changed more gently than that of glucose solution alone. The degree of the effect depended on the amount of “kajime”. Secretion of insulin was also depressed by the administration of “kajime”. We concluded that “kajime” had blood glucose- and serum insulin-flattening activity. The delay of gastric emptying was assumed to be one of main factors in the activity. © 1995, The Japanese Society of Fisheries Science. All rights reserved.
Article
The effects of adding non-starch polysaccharides (xanthan gum, guar gum, konjac glucomannan, and pectin) on the starch digestibility and viscosity of raw starch suspensions in a mixed system were determined. Each type of polysaccharide was added to high-amylose corn starch suspensions at defined concentrations. High-amylose rice starch suspensions mixed with xanthan and guar gum were prepared for comparison. The extent of starch digestibility was determined by an in vitro method, and the glucose diffusibility from the dialysis tube in the presence of polysaccharides was measured. The added polysaccharides were observed to decrease the starch digestibility in a mixed system. When compared at the same concentration, xanthan gum showed the most pronounced suppressive effect on starch digestibility and glucose diffusibility from the dialysis tube. The addition of polysaccharides increased the viscosity of the starch suspension. Significant relations were found between the extent of starch digestibility and the apparent viscosity at low shear rate.
Article
The starch digestibility and rheological properties of gels were evaluated in the presence of three non-starch polysaccharides (agar, xanthan gum and konjac glucomannan) with rice starch. Each polysaccharide was added to 30% (w/w) rice starch suspension at defined concentrations and starch gels were prepared. The extent of starch gel digestibility was determined by an in vitro method and rheological properties by a dynamic oscillatory test and a compression test. The added polysaccharides suppressed starch hydrolysis in the gels compared with the control, and a concentration dependency of this suppressive effect was observed. Adding agar and xanthan gum increased the storage shear modulus (G') of starch gels, while adding konjac glucomannan decreased G' values. The results indicate that the suppressive effect of non-starch polysaccharides on starch digestibility appears to be not only due to the rigidity of the gel, but also the interaction between starch and non-starch polysaccharides.
Article
Postprandila glycaemia and rise in serum insulin after carbohydrate-containing meals were reduced by the addition of guar flour or pectin, or both. After a liquid test meal (four subjects) the 30-min blood glucose was reduced from 6.33 +/- 0.19 mmol/litre (114 +/- mg/dl), mean +/- SEM, in the control subjects of 4.77 +/- 0.17 mmol/litre (86 +/- 3 mg/dl) by addition of guar gum (P less than 0.05). The mean insulin level was also significantly lower at 15 min. A breakfast test meal (bread, butter, marmalade, and tea) resulted in a mean 15-min blood glucose of 6.18 +/- 0.21 mmol/litre (111 +/- 4 mg/dl) in eight subjects; 10 g of pectin added to the marmalade reduced this level to 5.64 +/- 0.17 mmol/litre (102 +/- 3 mg/dl) (P less than 0.01). The insulin levels were significantly lower at 15, 30, and 45 min. A similar meal in which guar was added to the bread and pectin to the marmalade resulted in significant reductions of blood glucose at 15 min (P less than 0.002) and 30 min (P less than 0.01). The insulin values were also significantly lower throughout the first 90 min of the test. This action of unavailable carbohydrate may prove useful in the dietary control of diabetes.
Article
Experiments were carried out in vitro and in normal human subjects to evaluate alternative food-grade viscous polysaccharides as agents for reducing postprandial hyperglycemia and to assess the relationship between the in vitro and in vivo performance of the polysaccharides. A 1:1 mixture of xanthan and locust bean gum (X/LBG) had the greatest viscosity at equivalent concentrations and shear rates and was more effective than guar gum, xanthan, or locust-bean gum at inhibiting glucose movement in vitro. It was not, however, more efficient in lowering postprandial blood glucose and plasma insulin in human subjects when incorporated in a drink containing 50 g glucose. When the different gums were acidified and reneutralized to mimic conditions in the gut, there was a better correlation between viscosity and blood glucose and plasma insulin levels. This effect may explain why X/LBG was no more effective than the other gums in reducing postprandial hyperglycemia in man.
Article
Total available carbohydrate (sugars and starches) and total dietary fiber (soluble and insoluble) make up the total carbohydrate content of a food. Soluble fiber decreases the availability of glucose by delaying its absorption in the proximal small intestine, thus reducing the postprandial glucose levels (Jenkins et al., 1978; Schneeman, 1987a). Carrageenan, a seaweed extract, is a good source of soluble fiber (Montaño et al., 1985). This study aimed to determine the effect of carrageenan incorporation into arroz caldo on carbohydrate availability by monitoring the postprandial blood glucose levels of normal subjects. Control and experimental arroz caldo samples were prepared and subjected to proximate analysis and feeding studies. The total dietary fiber (TDF) content of the experimental (2.03%) was about thrice that of the control (0.68%). Using randomized crossover design, preweighed 55 g available carbohydrate serving portions of control and experimental arroz caldo samples, with 3.45 and 14.84 g TDF, respectively, were fed to ten fasting normal subjects then their postprandial blood glucose levels were determined at 15, 30, 45, 60 and 90 min intervals. Results of the short-term in vivo study showed that the mean postprandial glycaemic responses of subjects after consuming the experimental sample were significantly lower than the levels after consuming the control at 15, 45, and 90 min (P < or = 0.05) and at 30 min (P < or = 0.001). Likewise, the mean glucose area under the curve was significantly lower (P < or = 0.01) after consumption of experimental (69.22 +/- 32.94) arroz caldo than control (147.29 +/- 53.34). The hypoglycaemic effect of carrageenan may prove useful in the prevention and management of metabolic conditions such as diabetes.
Article
There have been many reports concerning the role of dietary fiber in lowering postprandial serum glucose, and the main mechanism was regarded as the viscosity of different dietary fibers in hampering diffusion of glucose and postponing absorption and digestion of carbohydrates. In this paper, two kinds of water-insoluble dietary fibers, water-insoluble dietary fiber of wheat bran and enzyme-resistant starch of maize amylose, and four kinds of water-soluble dietary fibers, water-soluble dietary fiber of wheat bran, carboxymethyl cellulose, guar gum, and xanthan gum, were used to investigate their postprandial serum glucose lowering mechanism in vitro. The results showed that these dietary fibers lowered postprandial serum glucose levels at least by three mechanisms. First, dietary fibers increase the viscosity of small intestine juice and hinder diffusion of glucose; second, they bind glucose and decrease the concentration of available glucose in the small intestine; and, third, they retard alpha-amylase action through capsuling starch and the enzyme and might directly inhibit the enzyme. All of these decreased the absorption rate of glucose and the concentration of postprandial serum glucose.
Article
The aim of this study was to evaluate the efficacy of agar diet in combination with a conventional diet (traditional Japanese food) for obese patients with impaired glucose tolerance and type 2 diabetes. After a 4-week run-in period on their habitual diets, 76 patients were randomly assigned to have conventional diet or conventional diet with agar. Both groups were on these diets for 12 weeks. Body weight, body mass index (BMI), glycaemic control, blood pressure, insulin resistance, total body fat, fat distribution and lipids were assessed before and after the experimental period. In both groups, after 12 weeks, mean body weight, BMI, fasting glucose levels, homeostasis model assessment-insulin resistance, and systolic and diastolic blood pressures had decreased significantly from their baseline values. HbA(1)c, visceral fat area, subcutaneous fat area, total body fat, insulin area under the curve after oral glucose tolerance test and total cholesterol decreased significantly in the agar-diet group. After 12 weeks, mean changes of body weight (-2.8 +/- 2.7 kg vs. -1.3 +/- 2.3 kg, p = 0.008), BMI values (-1.1 +/- 1.1 kg/m(2) vs. -0.5 +/- 0.9 kg/m(2), p = 0.009) and total cholesterol (-7.6 +/- 27.5 mg/dl vs. + 2.4 +/- 23.4 mg/dl, p = 0.036) were significantly greater in the agar-diet group than in the conventional diet group. The agar diet resulted in marked weight loss due to the maintenance of reduced calorie intake and to an improvement in metabolic parameters.
Effects of glucomannan and konjac noodles on the blood sugar level of cooked rice
  • M Fuwa
  • Y Nakanishi
  • H Ono
  • H Moritaka
The GI in vitro estimation of the monetary value of housework that assumed GR index
  • H Kumai
  • H Ooe
  • T Sasaki
  • J Matsuki
  • K Yoza
  • K Tokuyasu
Correlation between viscosity and plasma glucose and insulin flattening activities of pectins from vegetables and fruits in rats
  • K Ebihara
  • R Masuhara
  • S Kiriyama
  • M Manabe
Dietary fiber.” ILSI Europe Concise Monograph Series
  • G Juliet
Effect of agar on thermal property, sensory characteristic and glycemic index of cooked rice
  • H Moritaka
  • Y Nakanishi
  • M Fuwa
  • R Tanii
The National Health and Nutrition Survey in Japan, 2012.” Dai-ichi shuppan
  • Ministry
  • Health
  • Welfare
Toward practical application of the GR method. Presented at the 6th international conference on nutrition and aging
  • Y Nakanishi
Glycemic Index for Clinical Nutrition”. Dai-ichi shuppan
  • T Tanaka
  • M Suzuki
  • M Sugiyama