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1.
Spelt wheat seeds (Triticum aestivum subsp. spelta cv. Ostro) were used to obtain white spelt flour (64.5% yield), wholemeal spelt flour (100% yield), and scalded spelt wheat kernels. From these materials, white spelt wheat bread (WSB), wholemeal spelt wheat bread (WMSB), and spelt wheat bread with scalded spelt wheat kernels (SSKB) were made and were compared to the reference white wheat bread (WWB). The spelt wheat flours and breads contained more proteins in comparison to wheat flour and bread. Among the samples the highest rate of starch hydrolysis was noticed in WSB. During the first 30 min of incubation this particular bread was shown to have significantly more (P < 0.05) rapidly digestible starch than the WMSB and later on also more starch than in WWB and SSKB, respectively. The WMSB had the lowest hydrolysis index (HI = 95.7). However, the result did not differ significantly from that in the reference common wheat bread. On the other hand, the most refined spelt wheat flour resulted in a bread product (WSB) that was statistically withdrawn (P < 0.05) as one with the highest HI (112.6).  相似文献   

2.
Rye breads made from commercial rye blends lower the postprandial insulin demand and appear to facilitate glucose regulation. However, differences in metabolic responses may occur between rye varieties. In the present work, five rye varieties (Amilo, Evolo, Kaskelott, Picasso. and Vicello) and a commercial blend of rye grown in Sweden were investigated with regard to their postprandial insulin, glucose, and appetite regulation properties in a randomized crossover study in 20 healthy subjects. The rye flours were baked into whole grain breads, and a white wheat bread (WWB) was used as reference (50 g of available starch). Picasso and Vicello rye bread showed lower glycemic indices (GIs) compared with WWB (80 and 79, respectively) (P < .0.05). In addition to the GI, two measures of the glycemic profile (GP and GP(2)) were calculated by dividing the incremental duration of the plasma glucose curve with the incremental glucose peak and squared incremental glucose peak, respectively. Vicello and Picasso ryes were characterized by a higher GP(2) than that of the WWB, suggesting a better regulated course of glycemia. Rye bread made from not only Vicello and Picasso but also Amilo and Kaskelott displayed significantly lower insulin indices (IIs) than WWB (74-82). A high GP and GP(2) and a low GI were related to a lower II and insulin incremental peak. A high content of insoluble fibers and a high GP(2) were related to a higher subjective satiety in the early and late postprandial phase (tAUC 0-60 min and tAUC 120-180 min, respectively). The results suggest that there may be differences in the course of glycemia following different rye varieties, affecting postprandial insulin responses and subjective satiety.  相似文献   

3.
Pup‐loaf bread was made with 10, 30, and 50% substitution of flour with wheat starch phosphate, a cross‐linked resistant starch (XL‐RS4), while maintaining flour protein level at 11.0% (14% mb) by adding vital wheat gluten. Bread with 30% replacement of flour with laboratory‐prepared XL‐RS4 gave a specific volume of 5.9 cm3/g compared with 6.3 g/cm3 for negative control bread (no added wheat starch), and its crumb was 53% more firm than the control bread after 1 day at 25°C, but 13% more firm after 7 days. Total dietary fiber (TDF) in one‐day‐old bread made with commercial XL‐RS4 at 30% flour substitution increased 3–4% (db) in the control to 19.2% (db) in the test bread, while the sum of slowly digestible starch (SDS) plus resistant starch (RS), determined by a modified Englyst method, increased from 24.3 to 41.8% (db). The reference amount (50 g, as‐is) of that test bread would provide 5.5 g of dietary fiber with 10% fewer calories than control bread. Sugar‐snap cookies were made at 30 and 50% flour replacement with laboratory‐prepared XL‐RS4, potato starch, high‐amylose (70%) corn starch, and commercial heat‐moisture‐treated high‐amylose (70%) corn starch. The shape of cookies was affected by the added starches except for XL‐RS4. The reference amount (30 g, as‐is) of cookies made with commercial XL‐RS4 at 30% flour replacement contained 4.3 g (db) TDF and 3.4 g (db) RS, whereas the negative control contained 0.4 g TDF and 0.6 g RS. The retention of TDF in the baked foods containing added XL‐RS4 was calculated to be >80% for bread and 100% for cookies, while the retention of RS was 35–54% for bread and 106–113% for cookies.  相似文献   

4.
Rye products typically induce low insulin responses and appear to facilitate glucose regulation. The objective of this study was to investigate differences in postprandial glucose, insulin, and satiety responses between breads made from five rye varieties. Breads made from whole grain rye (Amilo, Rekrut, Dankowski Zlote, Nikita, and Haute Loire Pop) or a white wheat bread (WWB) were tested in a randomized cross-over design in 14 healthy subjects (50 g available starch). Metabolic responses were also related to the composition of dietary fiber and bioactive compounds in the breads and to the rate of in vitro starch hydrolysis. The Amilo and Rekrut rye breads induced significantly lower insulin indices (II) than WWB. Low early postprandial glucose and insulin responses (tAUC 0-60 min) were related to higher amounts of caffeic, ferulic, sinapic, and vanillic acids in the rye breads, indicating that the phenolic acids in rye may influence glycemic regulation. All rye breads induced significantly higher subjective feelings of fullness compared to WWB. A low II was related to a higher feeling of fullness and a lower desire to eat in the late postprandial phase (180 min). The data indicate that some rye varieties may be more insulin-saving than others, possibly due to differences in dietary fiber, rate of starch hydrolysis, and bioactive components such as phenolic acids.  相似文献   

5.
Cooked buckwheat groats are suggested to contain a greater amount of resistant starch (RS) than cereal grains. High RS content, in addition to dietary fibers present in groats, contributes to the low‐calorie, high‐fiber food status of buckwheat. Six buckwheat genotypes exhibiting high, medium, and low RS content of cooked groats were selected, and starches were isolated to determine their functional properties to explore the possible cause of high RS content of cooked buckwheat groats. Apparent and actual amylose contents were 27.4 and 31.6–34.5% in high, 27.4–28.6 and 32.5–33.7% in medium, and 21.4–25.6 and 24.5–32.0% in low RS genotypes, respectively. Genotypes of high RS content exhibited greater amylose leaching based on total starch content during cooking than genotypes of low RS content, mainly because of higher amylose content in the former than latter. Genotypes of low RS content exhibited a relatively high content of amylose‐lipid complexes, as determined with a differential scanning calorimeter (DSC). Gelatinization enthalpy and degree of amylopectin retrogradation determined with a DSC were not related to RS content. An evident relationship was observed between RS content of cooked groats and amylose retrogradation determined by gel hardness (r = 0.91, P < 0.05), cohesiveness (r = 0.89, P < 0.05), and syneresis (r = 0.88, P < 0.05). Increases in starch amylose content, amylose leaching capacity, and amylose retrogradation, as well as a decrease in the amount of amylose‐lipid complexes all appear to be related to high RS content of cooked buckwheat groats.  相似文献   

6.
High‐amylose wheat flour was used to substitute for normal wheat flour in breadmaking and formation of resistant starch (RS) in bread during storage was determined. Substitution with high‐amylose wheat flour (HAF) decreased peak and final viscosities, breakdown, and setback. Doughs with HAF substitutions were weaker and less elastic, and absorbed more water than those of the normal wheat flour. After baking, RS contents in breads with 10, 30, and 50% HAF substitutions were 1.6, 2.6, and 3.0% (db), respectively, higher than that of the control (0.9%, db). The levels of RS increased gradually during storage for one, three, and five days. With substitutions of 30 and 50% HAF, the total levels of dietary fiber (DF) and RS in bread after five days of storage were 15.5 and 16.8% (db), respectively, as compared to 13.0% (db) in bread from the normal wheat flour. The loaf volumes and appearances of bread crumbs made from HAF substitutions of 10 and 30% were not significantly different from those of the control, whereas the substitution with 50% HAF decreased loaf volume and resulted in inferior appearance of breadcrumbs. The firmness of breadcrumbs increased along with increase in the level of HAF substitutions after baking. During storage, the firmness of breadcrumb with 10% HAF substitutions was higher than that of the control, whereas breads with 30 and 50% HAF substitutions had similar firmness to the control. As a result, HAF might be used to substitute for up to 50% normal wheat flour to make bread with acceptable bread quality and significantly high amount of RS.  相似文献   

7.
The objective of this work was to study the formation of resistant starch (RS) in tortillas from an ecological nixtamalization process compared with the traditional nixtamalization process. The RS increased through all the steps of tortilla production. It was found that the increase of the RS corresponds mainly to the formation of RS5 (V‐amylose‐lipid complex), but in tortillas two major types of RS coexist: RS5 and RS3 (retrograded starch). In general, tortillas from the ecological nixtamalization process gave higher values of protein, lipids, total dietary fiber, insoluble fiber, soluble fiber, and RS compared with tortillas from the traditional nixtamalization process and commercial flour. The highest glycemic index (GI) occurred in the tortillas from commercial flour, whereas tortillas from 0.4% CaCO3 and 0.6% CaSO4 were classified as medium‐GI (GI 50–70). Tortillas from 0.6% CaCl2 had the lowest value of GI. The ecological nixtamalization processes caused significant differences in quality and nutritional properties of tortillas.  相似文献   

8.
Fagopyritols are mono-, di-, and trigalactosyl derivatives of D-chiro-inositol that accumulate in seeds of common buckwheat (Fagopyrum esculentum Moench) and may be important for seed maturation and as a dietary supplement. Fagopyritols and other soluble carbohydrates were assayed in mature groats and 11 milling fractions of common buckwheat seed. Because fagopyritols are in embryo and aleurone tissues, differences in fagopyritol concentrations reflect varying proportions of these tissues in each milling fraction. Bran milling fractions contained 6.4 g of total soluble carbohydrates per 100 g of dry weight, 55% of which was sucrose and 40% fagopyritols. Flour milling fractions had reduced fagopyritol concentration [0.7 g/100 g of dry weight total fagopyritols in the dark (Supreme) flour and 0.3 g/100 g in the light (Fancy) flours]. Fagopyritol B1 was 70% of total fagopyritols in all milling fractions. Fagopyritols were 40% of total soluble carbohydrates in groats of two cultivars of common buckwheat but 21% in groats of tartary buckwheat [Fagopyrum tataricum (L.) Gaertn.], probably a reflection of environment and genetics. A rhamnoglucoside present in tartary buckwheat was not detected in common buckwheat.  相似文献   

9.
Objectives of this study were to understand the physicochemical properties of a novel resistant starch (RS) made by complexing high‐amylose maize starch VII (HA7) with palmitic acid (PA), and its effects on reducing postprandial plasma‐glucose and insulin responses. The HA7 starch was heat‐treated and debranched using isoamylase (ISO) to enhance the starch‐lipid complex formation. The RS content of the HA7 starch debranched with ISO and complexed with PA (HA7+ISO+PA) was 52.7% determined using AOAC Method 991.43 for dietary fiber, which was greater than that of the HA7 control (35.4%). The increase in the RS content of the HA7+ISO+PA sample was attributed to the formation of retrograded debranched‐starch and starch‐lipid complex. The postprandial plasma‐glucose and insulin responses of 20 male human‐subjects after ingesting bread made from 60% (dry basis) HA7+ISO+PA were reduced to 55 and 43%, respectively, when compared with those after ingesting control white bread (as 100%) containing the same amount of total carbohydrates. The results suggested that the HA7+ISO+PA can be used for the interventions of insulin resistance and metabolic syndrome, including diabetes and obesity.  相似文献   

10.
Studies were conducted with two newly developed gluten‐free bread recipes. One was based on corn starch (relative amount 54), brown rice (25), soya (12.5), and buckwheat flour (8.5), while the other contained brown rice flour (50), skim milk powder (37.5), whole egg (30), potato (25), and corn starch (12.5), and soya flour (12.5). The hydrocolloids used were xanthan gum (1.25) and xanthan (0.9) plus konjac gum (1.5), respectively. Wheat bread and gluten‐free bread made from commercial flour mix were included for comparison. Baking tests showed that wheat and the bread made from the commercial flour mix yielded significantly higher loaf volumes (P < 0.01). All the gluten‐free breads were brittle after two days of storage, detectable by the occurrence of fracture, and the decrease in springiness (P < 0.01), cohesiveness (P < 0.01), and resilience (P < 0.01) derived from texture profile analysis. However, these changes were generally less pronounced for the dairy‐based gluten‐free bread, indicating a better keeping quality. Confocal laser‐scanning microscopy showed that the dairy‐based gluten‐free bread crumb contained network‐like structures resembling the gluten network in wheat bread crumb. It was concluded that the formation of a continuous protein phase is critical for an improved keeping quality of gluten‐free bread.  相似文献   

11.
One commercial bread wheat flour with medium strength (11.3% protein content, 14% mb) was fractionated into starch, gluten, and water solubles by hand‐washing. The starch fraction was separated further into large and small granules by repeated sedimentation. Large (10–40 μm diameter) and small (1–15 μm diameter) starch fractions were examined. Flour fractions were reconstituted to original levels in the flour using composites of varying weight percentages of starch granules: 0% small granules (100% large granules), 30, 60, and 100% (0% large granules). A modified straight‐dough method was used in an experimental baking test. Crumb grain and texture were significantly affected. The bread made from the reconstituted flour with 30% small granules and 70% large granules starch had the highest crumb grain score (4.0, subjective method), the highest peak fineness value (1,029), and the second‐highest elongation ratio (1.55). Inferior crumb grain scores and low fineness and elongation ratios were observed in breads made from flours with starch fractions with 100% small granules or 100% large granules. As the proportion of small granules increased in the reconstituted flour, it yielded bread with softer texture that was better maintained than the bread made from the reconstituted reference flour during storage.  相似文献   

12.
In search of a way to improve the nutritional profile of noodles, we prepared them with various mixtures of durum wheat flour and isolated plantain starch, and tested their proximal composition. Cooked noodles were assessed for in vitro starch digestibility, indigestible fraction content, and predicted glycemic index. The protein content declined with the addition of plantain starch. Both total starch (TS) level and the content of starch available for digestible enzymes (AS) decreased as the plantain starch level increased, a pattern that may be related to increased starch lixiviation during cooking of noodles containing plantain starch. There was an inverse pattern for resistant starch (RS). RS content in control (durum wheat flour) noodles was ≈50% lower than in the samples containing plantain starch. The soluble indigestible fraction (SIF) content in all samples was higher than the insoluble counterpart (IIF). The total indigestible fraction varied according to the wheat substitution level. Although the hydrolysis index (HI) and predicted glycemic index (pGI) of plantain starch noodles were moderate and decreased as the plantain starch proportion rose. These composite noodles exhibited higher indices than the control sample, a phenomenon that may also be dependent on the product physical structure. Results indicate that in spite of the increased starch digestion rate, plantain starch noodles are a better source of indigestible carbohydrates than pure wheat starch pasta. This might have dietetic applications.  相似文献   

13.
《Cereal Chemistry》2017,94(2):185-189
Bread flour was replaced with 5, 10, 15, 20, or 25% phosphorylated cross‐linked RS4 resistant wheat starch and augmented with vital wheat gluten to maintain original flour protein content. Effect on dough and bread characteristics, total dietary fiber content, and consumer acceptability were evaluated. Mixograph water absorption was not affected by addition of 5, 10, and 15% RS4; however, a significant 2% increase in absorption occurred with 20 and 25% RS4 addition. Mixograph mix time was increased by 15 s with the addition of 5, 10, and 15% RS4, by 30 s with 20% added RS4, and by 45 s with 25% added RS4. There was not a difference in farinograph absorption of doughs containing all levels of added RS4. Farinograph mixing time increased as addition level increased up to 15% and then decreased at higher addition levels. In general, dough strength and extensibility were not affected by RS4 addition. Levels of added RS4 up to 20% did not affect bread volume. Loaves with 15, 20, and 25% added RS4 contained sufficient fiber to meet the “good source of fiber” claim. A consumer sensory panel reported no difference in liking of flavor, texture, or overall liking of bread containing 15, 20, and 25% RS4.  相似文献   

14.
《Cereal Chemistry》2017,94(6):991-1000
Wheat, an important crop in North Dakota and the United States, is often used for bread. Health concerns related to chronic diseases have caused a shift toward consumption of whole wheat bread. There has been some indication that the rate and amount of starch digestibility of whole wheat breads may be lower than for their refined flour counterparts. This research investigated the components of whole wheat bread that may reduce starch digestibility and impact nutritional quality. Six formulations of flour were used, which included two refined flours, two whole wheat flours, and two whole wheat flours with added starch. The starch was added to whole wheat flours to increase the starch level to that of the refined flour so that we can determine whether or not the dilution of the starch in whole wheat bread was a factor in lowering the estimated glycemic index (eGI) of whole wheat bread. White and whole wheat flours and breads were evaluated for chemical composition, baking quality by 1 , and eGI by the Englyst assay. Whole wheat breads had significantly (P < 0.05) higher mineral, protein, arabinoxylan, and phenolic acid contents, as well as significantly (P < 0.05) lower eGI. The starch molecular weight was also significantly (P < 0.05) higher for whole wheat and whole wheat + starch breads compared with white breads. The eGIs of refined flour breads were 93.1 and 92.7, whereas the eGIs of whole wheat and whole wheat + starch breads ranged from 83.5 to 85.1. Overall, several factors in the whole wheat bread composition can be found to affect the quality and starch hydrolysis.  相似文献   

15.
To alleviate the adverse effects (grittiness and high crumb firmness) caused by the inclusion of sorghum flour in composite breads, sorghum grain was malted with the aim of decreasing the gelatinization temperature and increasing the water‐holding capacity of sorghum flour. Four different heat treatments were investigated: drying the malt at high temperatures (50–150°C), stewing, steaming, and boiling before drying the malt at 80°C. Malting decreased the pasting temperature of sorghum to values approaching those of wheat flour, but the paste viscosity was very low. Increasing the malt drying temperature inactivated the amylases but gave malts of darker color and bitter taste. Stewing, steaming, and boiling the malt before drying almost completely inactivated the amylases and increased the enzyme‐susceptible starch content and the paste viscosity of malt flours. Bread made with boiled malt flour (30%) had an improved crumb structure, crumb softness, water‐holding capacity, and resistance to staling, as well as a fine malt flavor compared with the bread made with grain sorghum flour (30%). Consumers preferred the malted sorghum bread over the bread made with plain sorghum flour.  相似文献   

16.
Buckwheat is a pseudocereal with a strong characteristic aroma. Compounds responsible for the aroma of buckwheat groats were recently identified, but the distribution of aromatic compounds between different fractions of the buckwheat kernel (flour, bran, and husk) is not yet known. In this study, the composition of aromatic compounds in buckwheat seed fractions was investigated and compared to the composition of aromatic compounds in groats produced from the same batch of buckwheat seeds. Volatiles from each sample were extracted with simultaneous distillation/extraction with a Likens‐Nickerson apparatus. Extracts were analyzed by gas chromatography coupled with mass spectrometry (GC‐MS) with electron ionization. Apart from the aroma molecules present in all fractions, compounds that are present only in flour or bran, but not in groats, were also found. Furthermore, some compounds were identified only in buckwheat groats but not in buckwheat flour or bran [octanal, (E,E)‐2,4‐heptadienal, (E)‐2‐decenal, and (E,E)‐2,4‐decadienal], others were identified only in husks [(E)‐2‐hexenal, heptanal, (E,E)‐2,4‐hexadienal, phenylacetaldehyde, and alpha‐bisabolol].  相似文献   

17.
The present investigation aims at understanding the role of chemically modified starch on the firmness of fresh or stale bread. Bread was prepared from wheat flour or substituted wheat flour that contained 18% chemically modified tapioca starch and 2% vital gluten. Hydroxypropylated tapioca starch (HTS), acetylated tapioca starch (ATS), phosphorylated cross‐linked tapioca starch (PTS), and native tapioca starch (NTS) were tested. Bread prepared from the substituted flour with PTS showed a firmer texture on the day of baking compared with bread prepared from NTS, HTS, and ATS. PTS retained its granular structure in the gluten network after baking and seemed to play the role of filler particles in the gluten matrix, thereby increasing firmness of fresh bread crumb. Bread prepared from the substituted flour with HTS or ATS firmed at a lower rate and showed a lower endothermic melting enthalpy of amylopectin after three days of storage compared with NTS or PTS. These findings suggest that the staling of bread containing chemically modified tapioca starch involves recrystallization of amylopectin.  相似文献   

18.
Wheat genotypes of wild type, partial waxy, and waxy starch were used to determine the influence of starch amylose content on French bread making quality of wheat flour. Starch amylose content and protein content of flours were 25.0–25.4% and 14.3–16.9% for wild type; 21.2 and 14.9% for single null partial waxy; 15.4–17.1% and 13.2–17.6% for double null partial waxy; and 1.8 and 19.3% for waxy starch, respectively. Wheat flours of double null partial waxy starch produced smaller or comparable loaf volume of bread than wheat flours of wild type and single null partial waxy starch. Waxy wheat flour, despite its high protein content, generally produced smaller volume of bread with highly porous, glutinous, and weak crumb than wheat flours of wild type and partial waxy starch. French bread baked from a flour of double null partial waxy starch using the sponge-and-dough method maintained greater crumb moisture content for 24 hr and softer crumb texture for 48 hr of storage compared with bread baked from a flour of wild type starch. In French bread baked using the straight-dough method, double null partial waxy wheat flours with protein content >14.3% exhibited comparable or greater moisture content of bread crumb during 48 hr of storage than wheat flours of wild type starch. While the crumb firmness of bread stored for 48 hr was >11.4 N in wheat flours of wild type starch, it was <10.6 N in single or double null partial waxy flours. Wheat flours of reduced starch amylose content could be desirable for production of French bread with better retained crumb moisture and softness during storage.  相似文献   

19.
A new method, a magnetic resonance imaging (MRI) technique characterized by T(2) relaxation time, was developed to study the water migration mechanism between arabinoxylan (AX) gels and gluten matrix in a whole wheat dough (WWD) system prepared from whole wheat flour (WWF) of different particle sizes. The water sequestration of AX gels in wheat bran was verified by the bran fortification test. The evaluations of baking quality of whole wheat bread (WWB) made from WWF with different particle sizes were performed by using SEM, FT-IR, and RP-HPLC techniques. Results showed that the WWB made from WWF of average particle size of 96.99 μm had better baking quality than those of the breads made from WWF of two other particle sizes, 50.21 and 235.40 μm. T(2) relaxation time testing indicated that the decreased particle size of WWF increased the water absorption of AX gels, which led to water migration from the gluten network to the AX gels and resulted in inferior baking quality of WWB.  相似文献   

20.
Buckwheat (Fagopyrum esculentum), a highly nutritious pseudocereal rich in bioactive compounds, is principally cultivated in central and eastern European countries. Buckwheat groats and husks of 10 cultivars were subjected to nutritional composition analysis and in vitro starch digestibility determination. Significant genetic variation was detected in buckwheat groats for 1,000‐kernel weight (16.5–39.8 g), protein content (10.2–17.9%), soluble dietary fiber (1.4–3.4%), insoluble dietary fiber (2.3–8.6%), total dietary fiber (3.6–10.6%), free phenolics (4.5–17.1 mg of gallic acid equivalent [GA]/g), and total phenolics content (6.8–20.7 mg of GA/g). The buckwheat husks exhibited large differences between cultivars in protein content (3.0–6.5%), bound phenolics (6.7–26.1 mg of GA/g), and total phenolics content (32.4–58.6 mg of GA/g), which was 1.5–8 times higher than in the groat. Cooked and cooled buckwheat groats exhibited lower starch digestibility and greater resistant starch content than raw buckwheat groats. Buckwheat cultivars with unique nutritional composition, such as Co901 and Ta‐1, were identified for future breeding.  相似文献   

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