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1.
R. Mujoo    P.K.W. Ng 《Journal of food science》2003,68(8):2448-2452
ABSTRACT: Grain of the soft white wheat cultivar Harus was harvested weekly from anthesis to maturity and fructooligosaccharides (FOS) contents were determined by reversed-phase high-performance liquid chromatography. Tests were carried out to determine the effect of adding immature wheat meal to a base flour of cultivar Russ (hard red spring) on the quality characteristics of bread. FOS content was also analyzed in baked bread, and the effect of transglutaminase in improving bread quality was examined. Marked decreases in FOS contents, such as 1-kestose and nystose, were observed with grain maturation. The overall quality of bread appeared to be acceptable, and the added FOS were retained after baking.  相似文献   

2.
This work is focused on the synthesis of the fructooligosaccharides (FOS) from sucrose using free inulinase from Kluyveromyces marxianus NRRL Y-7571 in aqueous and aqueous–organic systems. The most significant variables for the aqueous–organic system were identified using a fractional factorial design. The evaluated variables were the temperature, pH, sucrose concentration, inulinase activity, aqueous/organic ratio, and the polyethylene glycol concentration. The use of sequential experimental design methodology was shown to be very useful in the optimization of the FOS synthesis by inulinase either in aqueous or aqueous–organic systems. For the aqueous–organic system, the maximum Y FOS reached was 16.7 ± 1.1 wt.% with the following operational conditions: temperature of 40 °C, enzyme activity of 4 U mL−1, organic solvent/total system ratio of 25/100, pH of 6.0, and sucrose concentration of 55%. In the aqueous system, the maximum conversion obtained was 12.8 ± 1.0 wt.% under the following conditions: 40 °C, pH 5.0, 55% sucrose, and inulinase activity 4 U mL−1.  相似文献   

3.
The main objective of this study was to increase the folate content in Egyptian baladi bread using germinated wheat flour (GWF). The effect of germination temperature and drying conditions on the folate content of wheat grains was studied. Wheat flour was substituted with unsieved and sieved GWF at different levels and the effects on folate content and the rheological properties of dough were determined. Germination of wheat grains resulted in a 3- to 4-fold higher folate content depending on the germination temperature. Maximum folate content (61 μg/100 g dry matter (DM)) occurred at 30 °C. Drying did not affect folate content in germinated grains. After replacement with GWF, folate content in both flour and bread increased 1.5- to 4-fold depending on the level of replacement. Rheological properties of dough were adversely affected by increasing replacement level (as determined by farinograph). While the folate content in bread was as high as 66 μg/100 g DM at complete replacement of flour with sieved GWF, the bread was dark and layers were not separated. After replacement of half of the flour with sieved GWF (50 g/100 g), the baladi bread was acceptable with respect to colour and layer separation. The folate content in this bread was 50 μg/100 g DM, compared with 30 μg/100 g DM in bread without GWF (0 g/100 g).  相似文献   

4.
Grape seed flour (GSF) from grape pomace, a waste product generated during winemaking, was explored for use in bread production due to its potential health benefits. This study evaluated the consumer acceptance and physical properties of bread, including total phenolic content (TPC), made with varying levels of GSF. Dough and breads were prepared using different levels of replacement of hard red spring wheat flour (HRS) with GSF (0 to 10 g GSF/100 g HRS) and stored for 0, 2, or 6 wk at -20 °C. Replacement of 10 g GSF/100 g HRS increased the bread TPC from 0.064 mg tannic acid/g dry weight to 4.25 mg tannic acid/g dry weight. Consumer acceptance and instrumental analyses were used to investigate changes in sensory and texture properties due to GSF replacement. Replacement above 5 g GSF/100 g HRS decreased the loaf brightness and volume, with an increase in the bread hardness and porosity. Generally, breads containing ≥ 7.5 g GSF/100 g HRS were characterized by lower consumer acceptance. A reduction in overall and bitterness acceptance was observed in bread at 10 g GSF/100 g HRS, with decreased acceptance of astringency and sweetness at 7.5 and 10 g GSF/100 g HRS. Based on these results, the replacement of 5 g GSF/100 g HRS is recommended for the production of fortified breads with acceptable physical and sensory properties and high TPC activity compared to refined bread. PRACTICAL APPLICATIONS: This study shows that grape seed flour (GSF) can be used to replace hard red spring wheat flour (HRS) in bread production, with moderate impact on the physical and sensory properties of the bread. Replacement of up to 10 g GSF/100 g HRS significantly decreased overall consumer acceptance of the bread, with lower consumer acceptance of sweetness and astringency at 7.5 and 10 g GSF/100 g HRS. Thus, a replacement value of 5 g GSF/100 g HRS is recommended for the production of fortified breads.  相似文献   

5.
The present work was carried out with the aim to investigate some properties of an extracellular fructofuranosidase enzyme, with high transfructosylating activity, from Candida sp. LEB-I3 (Laboratory of Bioprocess Engineering, Unicamp, Brazil). The enzyme was produced through fermentation, and after cell separation from the fermented medium, the enzyme was concentrated by ethanol precipitation and than purified by anion exchange chromatography. The enzyme exhibited both fructofuranosidase (FA) and fructosyltransferase (FTA) activities on a low and high sucrose concentration. With sucrose as the substrate, the data fitted the Michaellis–Menten model for FA, showing rather a substrate inhibitory shape for fructosyltransferase activity. The K m and v max values were shown to be 13.4 g L−1 and 21.0 μmol mL−1 min−1 and 25.5 g L−1 and 52.5 μmol mL−1 min−1 for FA and FTA activities, respectively. FTA presented an inhibitory factor K i of 729.8 g L−1. The optimum conditions for FA activity were found to be pH 3.25–3.5 and temperatures around 69 °C, while for FTA, the optimum condition were 65 °C (±2 °C) and pH 4.00 (±0.25). Both activities were very stable at temperatures below 60 °C, while for FA, the best stability occurred at pH 5.0 and for FTA at pH  4.5–5.0. Despite the strong fructofuranosidase activity, causing hydrolysis of the fructooligosaccharides (FOS), the high transfructosilating activity allows a high FOS production from sucrose (44%).  相似文献   

6.
Response surface methodology (RSM) was used to analyze effects of hydroxypropylmethylcellulose (HPMC), yeast β-glucan, and whey protein isolate (WPI) on physical properties of gluten-free bread baked from formulas based on rice starch. A Box–Behnken design with three independent variables (HPMC, yeast β-glucan, and WPI) and three levels was used to develop models for the different responses (physical properties). Individual contour plots of the different responses produced from the models were compared to the corresponding reference wheat bread data and were superimposed to locate gluten-free bread formulations that met the wheat bread standards for spread ratio, specific volume, hardness, cohesiveness, chewiness, and crumb color L∗ value. The optimal formulation, determined from the data, contained 4.35 g/100 g HPMC, 1 g/100 g β-glucan, and 0.37 g/100 g WPI, rice starch basis. Predicted values of the optimized bread were experimentally tested and compared with the experimental wheat bread data. A good agreement among these data was observed. Moreover, the optimized rice starch bread was found to be acceptable according to the results of sensory analysis.  相似文献   

7.
The air flow pulverized grain flours were prepared from American wheat (AWF), Korean wheat (KWF), and corn (CRF) at 3 different grinding speeds, 9,000, 10,000, and 11,000 rpm. The effects of grinding speed on the physicochemical and bread making characteristics of resulting flours were investigated. Pulverization at low grinding speed produced the flour similar to those from conventional milling in particle size (80–100 μm). The higher speed grinding at 11,000 rpm produced grain flours with smaller particle sizes (20–30 μm) and higher amount of damaged starches. Accordingly, grinding speed increased water holding capacity, swelling power, and water solubility of the resulting grain flour, and also increased pasting properties. Gluten addition was needed for KWF (15% gluten) and CRF (30% gluten) to facilitate optimum bread making. The flour pulverized at high speed produced the KWF and CRF bread with the highest loaf volume and the lowest firmness.  相似文献   

8.
Yacon (Smallanthus sonchifolius) root is an important source of fructooligosaccharides (FOS). This study evaluated the influence of the blanching and drying processes on the sugars, FOS and colour of the obtained flour. Blanching in boiling water of 5 mm slices for 6 min allowed to inactivate 95% of polyphenol oxidase and peroxidase activity. Blanching solutions containing ascorbic, citric and lactic acid were detrimental in terms of FOS retention (68.2–87.4%) due to hydrolysis mainly of GF3, GF4 and GF5 FOS, and also important losses of reducing sugars (RS) were observed (69.5–87.4% retention). Blanching treatments that included ascorbic acid/CaCl2 prevented RS and FOS losses and improved colour of the obtained flour. The drying tested temperatures of 50–80 °C did not affect the RS retention and FOS losses associated to hydrolysis and the use of 80 °C rapidly reduced the water content and minimised browning reactions yielding flours with excellent colour characteristics with high FOS content that can be derived to the elaboration of prebiotic containing functional foods or for the extraction and purification of FOS.  相似文献   

9.
用冷榨、热榨、干法脱皮、湿法脱皮的方法制取芝麻分离蛋白后与面粉等其它成分混合制成面包。通过对各组面包进行感官评分,测定面包的体积、比容质构及面包芯水分,研究不同芝麻分离蛋白对面包品质的影响。结果表明:湿法脱皮组面包感官评分高于其他三组(p0.05);干法脱皮组、湿法脱皮组面包比容分别为3.16、3.57 mL/g,均低于热榨组、冷榨组(p0.05)。冷榨组面包100 g面包体积为491.35 cm3,高于其他三组,湿法脱皮组面包100 g面包体积为479.66 cm3,高于热榨组、干法脱皮组(p0.05)。湿法脱皮组面包硬度、咀嚼度分别为176.65、141.36,均低于其他三组(p0.05)。干法脱皮组面包弹性、回复性分别为0.87、0.23,高于其他三组。存放1 d、3 d、5 d时,湿法脱皮组面包水分减少速率分别为1.72%、0.97%、0.58%,低于其他三组(p0.05)。说明使用湿法脱皮芝麻分离蛋白制作的面包感官评分最高,面包质构最优,水分减少速率较慢,整体品质最理想。  相似文献   

10.
This study aimed to investigate effect of butter content (0–30 g/100 g flour) and baking conditions hot air baking (HA), microwave baking (MW) and hot air‐microwave baking (HA‐MW) on quality of the rice flour dough and bread. The increased butter (up to 15 g butter/100 g flour) enhanced elastic modulus (G′) and viscous modulus (G″) of dough and specific volume of bread. Additionally, the increased butter improved crust colour and reduced hardness of the bread. The HA‐MW and MW conditions were useful for the gluten‐free bread by reducing baking time and predicted glycemic index (GI), regardless of butter content. However, enthalpy of retrogradation and crystallinity in the HA‐MW and MW bread stored at 4 °C for 7 days were increased and higher than those of the HA bread, indicating a faster staling. The predicted GI of both MW and HA‐MW bread remained at a medium level during storage.  相似文献   

11.
In the paper, the authors present the qualitative and quantitative composition of quercetin glycosides and fructooligosaccharides (FOS) in onions commonly grown in Poland of the varieties: Napoleon, Sprinter and Grabowska from the 2006 and 2007 crops, stored in a cold room under standard conditions from October until February. Quercetin glycosides and FOS have been determined using the HPLC method. It has been demonstrated that the mean content of quercetin glycosides in the three varieties of onions from the 2006 and 2007 seasons is 1,381.6 ± 123.1 and 1,479.4 ± 125.5 mg/100 g d.m., respectively, in the edible part, whereby the proportion of quercetin 3-glucoside and quercetin 4′-glucoside amounts to about 60%. In 2006 in the three onion varieties the FOS content was on average 7.0 ± 1.2 g/100 g d.m., while in 2007 it was 6.2 ± 0.9 g/100 g d.m., of the edible part. The content of quercetin glycosides in outer and middle scales of the onions was 3,386.3 ± 190 and 1,017.4 ± 188 mg/100 g d.m., respectively. In the outer scales the FOS content was lower and amounted to 3.1 ± 0.2 g in 100 g d.m., while in the middle scales it was significantly higher 6.8 ± 0.7 g/100 g d.m. The content of quercetin glycosides in onions is high and remains at a constant level during storage; however, since they are found mainly in outer scales, their total removal with a view to obtaining white and milder culinary products results in a loss of approximately half of polyphenols.  相似文献   

12.
B. Renuka  P. Vijayanand 《LWT》2009,42(5):1031-1033
Fortification of selected fruit juice beverages (Pineapple, Mango and Orange juice) with fructooligosaccharides (FOSs), a low calorie prebiotic has been discussed. Results indicated that sucrose which is usually used as a sweetener in fruit juice beverages can be partially substituted with FOS without significantly affecting the overall quality. The fruit juice beverages were evaluated for physicochemical and sensory changes during 6 months storage period at ambient (25 ± 2 °C) and refrigeration temperature (4 °C). The pH, total soluble solids, titratable acidity, and colour did not change significantly (P ≥ 0.05) during storage. The initial FOS content of pineapple, mango and orange juice beverages was 3.79, 3.45, and 3.62 g/100 mL. The FOS content of the fruit juice beverages stored at refrigeration temperature was 2.00-2.39 g/100 mL after 6 months of storage and 2.69-3.32, 1.65-2.08 and 0.38-0.58 g/100 mL at the second, fourth and sixth months of storage at ambient temperature respectively. The sensory analysis showed that the beverages were acceptable up to 4 and 6 months storage at ambient and refrigeration temperature respectively.  相似文献   

13.
Pita bread loaves were prepared from flours fortified with calcium carbonate, calcium sulfate, and tricalcium dicitrate at 8 ascending levels to provide ranges of 800 to 2500, 700 to 1500, and 400 to 2000 mg of added Ca/100 g flour, respectively. The detection thresholds of calcium salts in pita bread were determined by the 3‐alter‐native forced choice (3‐AFC) test and construction of dose‐response curves. Detection thresholds determined by calculating geometric mean of individual best estimate thresholds, using criterion of 50%‐above‐chance and probit analysis of 3‐AFC data, were in the middle region of calcium concentrations. Analysis of dose‐response curves yielded values for thresholds outside the range of surveyed calcium concentrations. The detection threshold of CaSO4 (2724 mg/100 g) in pita bread was significantly higher (P < 0.01) than those of calcium carbonate (1984 mg/100 g) and tricalcium dicitrate (2132 mg/100 g). Calcium‐fortified pita bread was similar (P < 0.01) to its regular counterpart when formulated to contain 1254.6, 1772.5, or 1155 mg/100 g of CaCO3, CaSO4, or tricalcium dicitrate, respectively. At the indicated levels of fortification, calcium‐fortified pita bread is expected to provide between 61% and 126.5% of the recommended daily intake for calcium for Middle Eastern populations.  相似文献   

14.
The present study aimed to reduce the caloric value of bread by substituting a part of wheat flour with artichoke bracts at levels of 5%, 10% and 15% without sacrificing taste, texture or acceptability. Moreover, considerable trials had been made to reduce zinc deficiency in wheat bread and fiber‐enriched bread and also to study the effect of fiber on zinc bioavailability. Therefore, zinc sulphate was added to bread at levels of 40, 60, 80, 100 and 120 mg/100 g edible portion. The results from this study show that: (i) The addition of artichoke bracts to wheat flour increased the water absorption, arrival time, development time, and weakening of the dough as the level of artichoke bracts increased, while dough stability decreased. (ii) Mixing wheat flour with increasing amount of artichoke bracts increased the content of protein, fiber and total essential amino acids, also all essential amino acids increased in wheat bread and fiber‐enriched bread after fortification with zinc sulphate at a level of 100 mg/100 g edible portion except methionine, threonine and tyrosine. (iii) The best level of zinc sulphate to give the best bioavailability for zinc is 100 mg/100 g edible portion. (iv) Evaluation of fortified wheat bread and fiber‐enriched bread with zinc sulphate showed no significant difference by test panel.  相似文献   

15.
Subcritical water extraction (SWE) is one of the most promising modern extraction techniques for isolation of bioactive compounds from plant materials. Fructooligosaccharides (FOS) and beta-ecdysone were obtained from Brazilian ginseng roots (BGR) and aerial parts (BGA) by SWE aiming to use the entire plant in a biorefinery approach. The BGR extracts showed a FOS content of up to 8.8 g/100 g of extract and a beta-ecdysone content of up to 0.7 g/100 g of extract. BGA extracts showed a beta-ecdysone content of 0.3 g/100 g of extract. An economic evaluation showed that the manufacturing of BGR for beta-ecdysone production had a good profitability with a short payback time of 1.43 years, while BGA could be used as fuel to supply the energetic requirements of the process and then, enable the utilization of the entire plant.Industrial relevanceThis study reports the subcritical water extraction (SWE) of fructooligosaccharides (FOS) and beta-ecdysone from Brazilian ginseng roots (BGR) and aerial parts (BGA) aiming the use of the entire plant material in a biorefinery approach. SWE is a promising innovative technology to recover bioactive compounds from plant materials due to the easy manipulation of the dielectric constant of water. The economic evaluation of the process showed the great profitability of SWE to obtain bioactive compounds from Brazilian ginseng. These results demonstrated that SWE is a green, fast and economic process for extracting bioactive compounds from plant materials and can be successfully applied on industrial scale.  相似文献   

16.
For the development of healthful gluten-free soy bread acceptable to consumers, we evaluated the effects of various processing procedures for soy flour on bread quality, in terms of beany flavour and texture. We pretreated soy flour by both non-heating (raw:NS and germinated:GS) and heating (steamed:SS and roasted:RS) methods. In addition, to improve the loaf volume, we added 1% hydroxypropyl-methylcellulose (HPMC) to RS flour. Lipoxygenase activity was retained in the non-heat-treated flours (279 U/g for NS and 255 U/g for GS), but was significantly reduced in the heat-treated flours (106 U/g for SS and 69 U/g for RS). Moreover, heat-treated flour had higher isoflavone and ferric reducing antioxidant power than had non-heat-treated flour. However, RS flour had the lowest moisture content and lowest L value. The GS bread had the highest specific loaf volume (3.53 cm3/g), followed by NS (2.96 cm3/g), RS (2.25 cm3/g), and SS (1.81 cm3/g) bread. GS bread had the lowest hardness (1.53 N), followed by NS (1.65 N), RS (2.00 N), and SS (3.75 N) bread. The addition of 1% HPMC to RS increased the loaf volume (2.44 cm3/g), but decreased the bread’s hardness (1.80 N). As to the sensory properties, the bread with heat-treated flour was perceived to have a less beany odour and taste than was the bread with non-heat-treated flour. However, the latter had a better appearance than the former. These results indicated that soy flour pretreatment could enhance the loaf volume and reduce the beany flavour of whole soy bread.  相似文献   

17.
Abstract: The natural mixed culture kefir was immobilized on boiled corn grains to produce an efficient biocatalyst for lactic acid fermentation with direct applications in food production, such as sourdough bread making. The immobilized biocatalyst was initially evaluated for its efficiency for lactic acid production by fermentation of cheese whey at various temperatures. The immobilized cells increased the fermentation rate and enhanced lactic acid production compared to free kefir cells. Maximum lactic acid yield (68.8 g/100 g) and lactic acid productivity (12.6 g/L per day) were obtained during fermentation by immobilized cells at 37 °C. The immobilized biocatalyst was then assessed as culture for sourdough bread making. The produced sourdough breads had satisfactory specific loaf volumes and good sensory characteristics. Specifically, bread made by addition of 60% w/w sourdough containing kefir immobilized on corn was more resistant regarding mould spoilage (appearance during the 11th day), probably due to higher lactic acid produced (2.86 g/Kg of bread) compared to the control samples. The sourdough breads made with the immobilized biocatalyst had aroma profiles similar to that of the control samples as shown by headspace SPME GC‐MS analysis.  相似文献   

18.
The effects of green tea powder (GTP) on the properties of hard red winter (HRW) flour and Chinese steamed bread were investigated. GTP was blended with HRW flour at levels of 0.00, 1.00, 2.00, 3.00 and 4.00 g GTP/100 g wheat flour. With the addition of GTP, the maximum torque of flour became stronger. The resilience and degree of green colour of steamed bread increased, while hardness and chewiness decreased, with the addition of GTP. The addition of 1.00% GTP did not significantly affect the specific volume, but remarkably influenced the hardness and resilience of steamed bread. In steamed bread formulated with GTP, the antioxidant activity was 0.84 mm TE per g at 1.00% of GTP and increased with GTP levels. The steamed bread had a pleasant flavour, and the degree of overall liking of steamed bread increased with GTP levels to the maximum used in this work.  相似文献   

19.
ABSTRACT: The objective of this study was to assess the status of fructooligosaccharides (FOS) in onion bulbs ( Allium cepa L. cv. Tenshin) and their metabolizing-enzymes—1-fructoexohydrolase (1-FEH), 1-kestose hydrolyzing enzyme (1-KH), fructan:fructan 1F-fructosyltransferase (1-FFT) and fructan:fructan 6G-fructosyltransferase (6G-FFT)—during storage at 15°C. Fructose varies slightly, whereas 1-kestose peaked after 6 wk and then decreased progressively during the last 18 wk of storage. Lower degree of polymerization (DP) 3 to 6) FOS, higher (DP 7 to 12) FOS, total FOS, and total carbohydrates showed similar and close patterns during 24 wk. They varied slightly at the beginning of the storage period; afterward they decreased progressively and regularly during the last 20 wk of storage. 1-FEH and 1-KH activities were low but peaked abruptly after 12 and 16 wk, respectively, after which they decreased to levels higher (1-FEH) or similar (1-KH) to those observed at the beginning of the storage. Surprisingly, 1-FFT activity showed similar pattern to the variation of 1-KH hydrolyzing activity; on the other hand, 6G-FFT, although higher, was stable during 16 wk but decreased after that. The results allowed us to associate FOS to the dormancy and sprouting states, and the peaks of the degrading enzymes were shown to signal the release of dormancy of onion bulb.  相似文献   

20.
The rheological and baking properties of flaxseed/wheat composite flours were studied. Flaxseed flour was used to replace 50, 100, 150 and 200 g kg?1 of wheat flour in bread. Farinographic studies showed that water absorption, dough development time and mixing tolerance index increased as the amount of flaxseed flour increased, while dough stability decreased at 100, 150 and 200 g kg?1 of flaxseed flour substitution. The extensographic energy of dough also decreased at 150 and 200 g kg?1 flaxseed levels. The addition of increasing amounts of flaxseed flour caused a decrease in extensibility. Doughs containing 100, 150 and 200 g kg?1 flaxseed flour showed resistance to extension comparable to that of control dough. The specific volume of flaxseed flour breads was similar to that of control bread. Crust L, a, b values of breads with flaxseed flour were lower than those of control bread. Breads with flaxseed flour gave lower crumb L and b values and higher a values than control bread. The sensory properties showed that an acceptable bread could be produced using flaxseed flour up to a level of 200 g kg?1. Copyright © 2007 Society of Chemical Industry  相似文献   

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