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1.
The importance of dietary betaine is increasingly recognized. The aim of this study was to develop a simple high-performance liquid chromatography with standard ultraviolet spectrometric detection (HPLC-UV) method for betaine (N,N,N-trimethylglycine) determination in foods after derivatization. Two methods were used for betaine derivatization. Thereafter, derivatized betaine was quantified using HPLC-UV, and the results were compared with liquid chromatography mass spectrometry (LC-MS). The established derivatizing agent 2′-naphthacyl triflate and a novel derivatizing agent 2-bromo-2′-acetonaphthone produced the same cationic derivative when they react with betaine. The calibration curves were linear up to 1000 μmol/L (R 2?=?0.9974 for 2′-naphthacyl triflate and 0.9995 for 2-bromo-2′-acetonaphthone). The limit of detection was 1 μmol/L for both methods (2′-naphthacyl triflate and 2-bromo-2′-acetonaphthone), confirming sufficient sensitivity for betaine quantification in foods. The average recovery from different food matrices (wheat flour and spinach) (n?=?12) was 99?±?9 %, 95?±?10 %, and 101?±?8 % for LC-MS, 2′-naphthacyl triflate, and 2-bromo-2′-acetonaphthone, respectively. Inter- and intra-assay coefficients of variation (CVs) in the control samples (whole wheat flour) were below 10 %. Quantitative results for foods analyzed using 2′-naphthacyl triflate and 2-bromo-2′-acetonaphthone were comparable to LC-MS (R 2?=?0.992 and 0.990), respectively. The highest betaine content (~160 mg/100 g) was found in spinach followed by faba bean, wheat flour, and beetroot. These methods can be widely used for betaine quantification because of the simplicity of the derivatization procedures, and the commercial availability of the derivatizing reagent (2-bromo-2′-acetonaphthone) or through the relatively easy synthesis of 2-naphthacyl triflate.  相似文献   

2.
The effect of different enriched fibre products obtained from butternut (Cucurbita moschata Duchesne ex Poiret) on bread making and bread quality was evaluated through the study of bread yield, quality parameters (specific volume, crumb firmness, crumb and crust colour) and bread shelf life. Fractions tested were obtained from butternut mesocarp through ethanolic treatment (fraction AIR) or through dehydration (fraction S) or from the ethanolic treatment of peel (fraction C). These fractions were incorporated in a bread formula, at levels of 5, 10 and 15 g of fibre fraction per kilogram of wheat flour. The study of crumb through digital imaging and thermal analysis was also performed in order to better understand the effects observed. An important influence of water absorption kinetics and chemical composition of the fibre fractions studied was observed in the results obtained. Lower bread firmness was determined 24 h after baking when 10 g of C or either 10 or 15 g of S was present per kilogram of wheat flour used. Breads made with flour containing 10–15 g of S or 5 g of C per kilogram of wheat flour tended to be softer, while 10 g of C per kilogram of flour produced significantly softer breads along 9 days storage.  相似文献   

3.
The tocopherols in freshly milled flour were measured using two-dimensional chromatography. Total tocopherols were in the range 1500–1600 μg/100 ml, but only 17–18% of this was α-tocopherol. Aerobic storage for 190 days caused a reduction of all tocopherols by 62–67%. Treatment of the flour with chlorine dioxide at the usual commercial level caused a comparable reduction, averaging 58%; ?-tocopherol was rather less affected than α-tocopherol. Studies in human volunteers indicated that a daily supplement greater than 10 mg of tocopherol was needed to bring about a significant change in the level of α-tocopherol in the blood. When bread made from untreated and chlorine dioxide-treated flour was fed to groups of volunteers in a double-blind crossover trial for 50 days on each type of bread, no significant correlation could be found between blood tocopherol levels and the type of bread consumed. To examine whether a longer period of time on the diet was necessary, the blood tocopherol levels of thirteen English students who had habitually consumed bread made from treated flour were compared with those of thirteen French students, matched for age, who had for several years consumed French bread which is made from untreated flour. The analyses were carried out in Birmingham and in Paris by the same investigator. No significant differences in tocopherol levels were found. It is concluded that the consumption of bread made from flour treated with chlorine dioxide will have no significant effect upon the blood level of α-tocopherols under the dietary conditions at present prevailing in Britain.  相似文献   

4.
Thermal and non-thermal processing may alter the structure and improve the techno-functional properties of pulses and pulse flours, increasing their range of applications in protein-enhanced foods. The effects of germination and toasting of yellow peas (Pisum sativum) on flour and dough characteristics were investigated. Wheat flour was substituted with raw, germinated and toasted pea flour (30%). The resulting bread-baking properties were assessed. Toasting increased dough water absorption and improved dough stability compared with germinated and raw pea flour (p < 0.05). This resulted in bread loaves with comparable specific volume and loaf density to that of a wheat flour control. Significant correlations between dough rheological properties and loaf characteristics were observed. Addition of pea flours increased the protein content of the breads from 8.4% in the control white bread, to 10.1–10.8% (p < 0.001). Toasting demonstrated the potential to improve the techno-functional properties of pea flour. Results highlight the potential application of pea flour in bread-making to increase the protein content.  相似文献   

5.
The effect of partial substitution of wheat flour with reduced‐fat peanut flour at different levels (10, 20, 30, 40, and 50%) on physical parameters, proximate composition, sensory profile, and shelf stability of bread were investigated. Loaf volume, specific volume, and crumb density were significantly (p ≤ .05) reduced with increasing level of substitution with the peanut flour. Peanut flour had significant (p ≤ .05) improvement on the protein content and reduction in carbohydrate content of loaves. Consumers preferred the taste aroma and color of the peanut–wheat flour composite loaves at ≥20% peanut flour inclusion. Freshly baked composite peanut–wheat bread loaves with 10% level of peanut substitution had higher overall acceptability than 100% wheat flour formulation but less microbial stability during storage. Reduced fat‐peanut has potential application for improving the nutritional quality and shelf stability of wheat flour bread.

Practical applications

The demand for convenient alternative to conventional foods is on the increase with the dynamics of the world's social values, lifestyles, and demographic trends. Having peanut incorporated into dough (as one food system) will offer convenience to consumer and therefore add value to bread variety on market shelves. Assessing the influence of the peanut flour on bread quality provides first‐hand information that can facilitate optimization of the baking process toward commercial production of peanut–wheat flour bread.  相似文献   

6.
木糖醇对面包粉回生特性影响   总被引:1,自引:0,他引:1  
以面包专用粉为原料,添加不同质量浓度木糖醇,通过测定熟化后面包粉硬度、冻融稳定性及糊化特性研究木糖醇对面包粉回生特性影响。结果表明,添加木糖醇后,熟化后面包粉回生硬度明显降低,添加0.50 g/g木糖醇面包粉在4℃条件下回生5 d、7 d硬度较原面包粉分别降低37.31%、57.45%;面包粉冻融稳定性显著增强,原面包粉冻融循环4次失水率为47.39%,而添加0.20g/g木糖醇样品失水率为22.91%,比原面包粉减少24.48%;经RVA测定,添加0.20 g/g、0.50g/g木糖醇面粉与原面粉相比,峰值粘度显著增加;表明添加木糖醇对面包粉回生具有抑制作用。  相似文献   

7.
Wheat is primarily used for bread-making. However, fungal diseases, grain moisture at harvest and low-protein contents strongly influence the quality of the wheat flour, thus creating challenges for traders, millers and commercial bakers who struggle to produce consistently high-quality products. This paper address the replacement of low-protein/wholemeal flour functionality for bread-making purposes. Three hydrocolloids, xanthan gum, dextran and hydroxypropyl methylcellulose, were incorporated into bread recipes based on high-protein flours, low-protein flours and coarse wholemeal flour. Hydrocolloid levels of 0–5 % (flour basis) were used in bread recipes to test the water absorption. The quality parameters of dough (farinograph, extensograph, rheofermentometre) and bread (specific volume, crumb structure and staling profile) were determined. Results showed that xanthan had negative impact on the dough and bread quality characteristics. HPMC and dextran generally improved dough and bread quality and showed dosage dependence. Volume of low-protein flour breads were significantly improved by incorporation of 0.5 % of the latter two hydrocolloids. However, dextran outperformed HPMC regarding initial bread hardness and staling shelf life regardless the flour applied in the formulation.  相似文献   

8.
In view of the frequent occurrence of mycotoxins in cereals, a study was initiated to assess the exposure of the Hungarian adult population. Consumption data for 1360 individuals, based on a 3-day questionnaire, indicated that white bread accounted for the major intake of cereal-based products. Various cereal products were analysed for 16 mycotoxins by a LC/MS/MS multi-toxin method with LOD of 16?µg?kg?1 and LOQ of 50?µg?kg?1. Deoxynivalenol (DON) was most frequently detected, but no acetyl-deoxynivalenol was present in detectable concentrations. Consumer exposure was calculated with standard Monte Carlo probabilistic modelling and point estimates, taking into account bread consumption and DON contamination in independently taken wheat flour and wheat grain samples. Over 55% of cases the DON intake were below 15% of the provisional maximum tolerable daily intake (PMTDI) of 1?µg/(kg?bw)/day. However, in 5–15% of cases, the intake from bread consumption alone exceeded the PMTDI. Wheat grain data led to the higher percentage. Intakes estimated from both data sets were at or below the acute reference dose (ARfD) of 8?µg/(kg?bw)/day in 99.94–99.97% of cases.  相似文献   

9.
以面包专用粉为主料,添加紫苏油粕粉制备具有紫苏风味的紫苏面包粉,并添加适量的谷朊粉改善其粉质特性,采用粉质仪检测,以吸水量、形成时间、稳定时间和质量指数为考核指标,研究紫苏油粕粉和谷朊粉添加量对紫苏面包粉品质的影响。结果表明,紫苏油粕粉添加量10%,谷朊粉添加7%时,紫苏面包粉粉质最优:吸水量60.9%,形成时间10 min20s,稳定时间12min 36s,质量指数140。  相似文献   

10.
The micronutrient composition of the flour, dough and the bread has been investigated by means of inductively coupled plasma atomic emission spectrometer (AES-ICP). The obtained experimental data demonstrate the existence of a low micronutrient content in bread and the necessity for its fortification to provide a really wholesome diet.  相似文献   

11.
This study was conducted to determine the effects of dietary glycine betaine on pork quality and blood characteristics. A total of 80 female pigs (Landrace  ×  Yorkshire  ×  Duroc) were randomly allotted into one of four experimental diet groups. Each group of pigs fed with a commercial diet (control) added with 0.2 g glycine betaine (T1), 0.4 g glycine betaine (T2) and 0.6 g glycine betaine (T3)/kg diet during 40 days. Glycine betaine concentrations in plasma and loin muscle were significantly increased by dietary glycine betaine; however, triglyceride concentration in serum was decreased by dietary glycine betaine. Creatine phosphokinase concentrations in plasma had no significant difference among the dietary groups. Redness ( a* ) was significantly higher in T2 and T3; however, at the first and seventh days of storage, redness ( a* ) was not significantly different between dietary groups. Shear force was significantly higher in dietary glycine betaine groups at the first day of storage. Cholesterol content was significantly lower in T2 and T3, whereas T1 was not significantly different compared with the control group. In fatty acid composition, the ratio of saturated fatty acids was increased, whereas unsaturated fatty acids were decreased by dietary glycine betaine.

PRACTICAL APPLICATIONS


Glycine betaine is an amino acid (trimethylglycine) present in most organisms, and is an obligatory intermediate in the catabolism of choline. Glycine betaine has been reported to affect some aspects of pork qualities. As a result of this study, dietary glycine betaine should improve meat redness and reduce cholesterol. However, dietary glycine betaine did not influence creatine phosphokinase levels in plasma. These results will be helpful to the pork industry and meat scientists for improving meat qaulity.  相似文献   

12.

ABSTRACT

The effects of pentosanase at different doses (20, 60 and 100 ppm) on physical dough properties and bread quality were studied using three types of wheat flours. Flour A was a regular bread flour, flour B had a high hardness ratio and protein content, and flour C was prepared from the same blend of flour A but had a high extraction ratio. Regarding farinograph data, water absorption values of the high extraction (86%) flour C and high hardness (65%) blend flour B increased with introduction of pentosanase. Extensibility values of the flours increased moderately with pentosanase addition, while resistance and energy values decreased. The volume of breads made with flours C and B decreased upon addition of pentosanase. But loaf volume of breads prepared with regular bread flour A with 50% hardness and 76% extraction rate increased with high levels of pentosanase addition. In conclusion, flour A as a regular bread flour gave satisfactory results with pentosanase supplementations, whereas the harder‐blend (65%) and higher‐extraction‐rate (85%) flours from the same cultivars did not.

PRACTICAL APPLICATIONS

Pentosanase addition was more effective on soluble pentosans than on insoluble ones. Because of these effects, it enhanced the bread‐making properties of regular flour more effectively than those of the high‐extraction and harder‐blend flours of the same cultivars.
  相似文献   

13.
Bread is consumed in large quantities all over the world, and rye bread is especially popular throughout the Nordic countries. Wholemeal bread is highly recommended as a basic ingredient in daily food, because wholemeal food products generally promote good health due to their vitamin, mineral and fibre content. The literature suggests that wholemeal products have other health-promoting effects even if the ingredients responsible have not been identified. Benzoxazinoids are a group of natural products that have not previously been reported in mature grains. Here, we report for the first time the identity and quantity of 10 compounds of the benzoxazinoid family in mature grains, hydrothermally processed grains of durum wheat (Triticum durum, cv. Kamut), a commercial variety of rye (Secale cereale cv. Picasso) and an old Nordic rye landrace (S. cereale, Svedjerug), as well as in bread baked with flour milled from those grains. Concentrations of the 10 benzoxanoids were determined using LC–MS/MS and ranged from 0 to 348 nmol g−1 for conventional flour, to 772–1177 nmol g−1 in bread baked with flour from hydrothermally processed grains and to 3116–5570 nmol g−1 in flour from hydrothermally processed grains. Benzoxazinoids possess documented physiological effects, and research into the importance of these compounds in the daily diet is therefore needed. Ongoing studies in our lab on the uptake and transformation of benzoxazinoids in mammals will be reported in the near future.  相似文献   

14.
The importance of polyunsaturated fatty acids (PUFA) in health and nutrition is well recognised. Flaxseed (Linum usitatissimum) has recently gained a lot of attention as functional food because of its unique nutrient profile. In the present work efforts were made to develop omega-3 enriched functional bread using raw and roasted ground flaxseed flour. Initially optimisation of each bread ingredient viz., salt, sugar, and shortening, GMS, yeast and water was carried out on the basis of sensory overall acceptability score. The standardised bread was incorporated with raw and roasted ground flaxseed (5, 10, and 15 g/100 g) flour. The effect of flaxseed incorporation on bread dough rheology parameters viz., dough stickiness and water absorption was studied. Increase in water absorption and dough stickiness was observed with increased flaxseed level. Further breads were evaluated for sensory parameters, colour and texture. The crumb softness increased with increase in flaxseed level. Bread was optimised at 10(g/100 g) flaxseed level based on sensory evaluation.  相似文献   

15.
The effect of blending of fenugreek (raw, soaked, and germinated) flour (Trigonella faenum graecum) from 5 to 20% in wheat flour on the rheological and sensory evaluation of bread, biscuit, noodle, and macroni was studied. Farinograph water absorption, dough development time, mixing tolerance index, and dough stability increased significantly with increased amount of fenugreek flour. Incorporation of fenugreek flour in wheat flour increased the protein and fat contents of blends but decreased the gluten contents. Among the supplemented blends, blends containing germinated fenugreek flour had higher protein contents (13.83–16.30%) up to 20%. Overall acceptability scores of bread, biscuit, noodles, and macroni were found highly acceptable up to 15, 10, and 20% levels, respectively.  相似文献   

16.
BACKGROUND: The interaction between lipoxygenase‐active soybean flour (LOX) and ascorbic acid (AA), on colour, rheological and sensory properties of wheat bread was studied with the aim of reducing the applied quantity of additives in bread formulations. RESULTS: The ascorbic acid (0–500 ppm) and active soybean flour (0–1%) mixture improved bread‐crumb colour by lowering the yellow hue in a higher proportion than those expressed by the components alone, characterising a synergistic mechanism (?b = 15.1? (1.7 × LOX) ? (0.5 × AA) ? (5.8 × LOX × AA), where ?b represent the estimated value for the yellow hue parameter). No differences in flavour and porosity were seen between the samples. As supported by the instrumental methods, breads made with active soybean flour and ascorbic acid (LOX + AA) had whiter crumbs and were softer and springier than controls as assessed by a trained sensory panel. In summary, the combination of both active soybean flour and ascorbic acid showed synergism, promoting a greater bleaching effect than when used alone. CONCLUSION: These results suggest the potential use of active soybean flour as a synergistic ingredient in the substitution of artificial additives in bread making. Since the interaction on the bleaching response was not linear and active soybean flour showed a higher iron concentration (66.40 ± 4.23 µg g?1) than non‐active soybean flour (52.30 ± 0.40 µg g?1), more studies are warranted to establish the biochemical mechanisms involved in this interaction. Copyright © 2007 Society of Chemical Industry  相似文献   

17.
The polysaccharide in the fruit bodies of Auricularia auricula (commonly called black woody ear or tree ear) was extracted, lyophilized and ground. Auricularia auricula polysaccharide (AAP) flour blended bread was developed. Physical qualities and antioxidant activities of breads with different levels of substitution of AAP flour for wheat flour were analyzed.The results showed that up to 9% of AAP flour could be included in bread formulation without altering the sensory acceptance of the blended bread. The incorporation of AAP in bread markedly increased the antioxidant property of the bread as tested by DPPH free radical-scavenging method. Breads containing AAP flour can broaden the utilization of the fruit bodies of Auricularia auricula and may be regarded as possible health-promoting functional foods.  相似文献   

18.
《Food chemistry》1999,65(4):433-437
This work shows the results of comparing the effects of the insoluble dietary fibre from oil palm fat-free flour and cellulose on the growth, weight, humidity and composition of faeces in adult rats (Sprague–Dawley). Five groups of rats were fed for 4 weeks. The control group was fed with a diet free of fibre, and the remaining four groups with diets containing 50 or 100 g of either oil palm fat-free flour or cellulose, respectively. The adaptation period was 4 days. The evolution of growth and food intake did not vary significantly p<0.05 regardless of the type of diet. On the other hand, faeces excretion increased by 3.3–4.7 g/day in the groups of rats fed with oil palm fat-free flour, while it increased by only 3.1–4 g/day in diets based on cellulose. A higher content of water was observed in the faeces of rats fed with insoluble dietetic fibre from oil palm fat-free flour. The apparent digestibility of the insoluble dietary fibre of oil palm fat-free flour was low (35%), showing resistance to fermentation. The digestibility of the protein tended to decrease more with the insoluble dietary fibre of oil palm than with the cellulose, which may be related. ©  相似文献   

19.
Animals and insects are the main sources of protein. The objective of the present study was to produce a flour from cinereous cockroach (Nauphoeta cinerea) for protein enrichment of wheat bread. To prepare the flour, the dehydrated insects were crushed and sieved to reduce the granulometry to a particle size of 1.18 mm. The flour was analyzed microbiologically and then added in amounts of 5, 10, and 15% (based on wheat flour) in a bread formulation that was analyzed for chemical composition and color, firmness, and specific volume and compared to white wheat bread and whole wheat bread. Sensorial evaluation was carried out on bread enriched with 10% roasted flour as the one that presented the best nutritional characteristics, differing little from the white and whole wheat bread. It is concluded that the use of cinereous cockroach (Nauphoeta cinerea) flour is an efficient way to enrich wheat bread without alterations in sensorial quality.  相似文献   

20.
《Food chemistry》2002,77(4):479-488
Supplementations of soy (full fat and defatted) and barley flours to wheat flours at 5, 10, 15 and 20% levels were carried out to test the effects on organoleptic and nutritional evaluation of the supplemented bread. Additions of 15% barley flour, 10% soy flour (full fat and defatted), 15% barley plus full fat soy flour and 15% barley plus defatted soy flour to wheat flour produced acceptable breads. However, substitution of soy (full fat and defatted) and barley flours to wheat flour separately and in combinations at 20% levels did not produce organoleptically acceptable bread. Various nutritional parameters, such as protein, fat, total lysine, protein digestibility (in vitro), sugars, starch digestibility (in vitro), total and available minerals, antinutrients, dietary fibre and β-glucan were determined in supplemented and control bread. Increasing the level of substitution from 5 to 10% of full fat and defatted soy flour to wheat flour significantly (P<0.05) increased protein (from 12.1 to 13.7 and 12.4 to 13.8%), lysine (from 2.74 to 3.02 and 2.76–3.05 mg/100 g protein) and total calcium (from 70.2 to 81.4 and 71.9–81.8 mg/100 g) contents. However, there was also an increase in phytic acid (238–260 and 233–253 mg/100 g), polyphenol (324–331 and 321–329 mg/100 g) and trypsin inhibitor activity (193–204 and 193–198 TIU/g). When barley flour was substituted separately, and in combinations, with full fat and defatted soy flour up to 15%, this significantly increased the contents of protein, total lysine, dietary fibre and β-glucan. It may be concluded that breads supplemented with barley and defatted soy flour, up to a 15% level, are organoleptically and nutritionally acceptable.  相似文献   

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