Valorization of wheat bran arabinoxylan: A review on nutritional and materials perspectives

Wheat bran, a principal byproduct of flour milling, stands as an abundant source of dietary fiber, yet its economic potential remains under-exploited in current forage applications. Arabinoxylan(AX), constituting the core of dietary fiber, emerges as a versatile compound with multifaceted functionalities. Its nutritional significance,coupled with its role in cereal food processing, has prompted a surge of studies focusing on the valorization of wheat bran AX. Moreover, the hydrolyzed derivative, arabinoxylan oligosaccharides(AXOS), demonstrates prebiotic and antioxidant properties, offering potential avenues to mitigate the risk of chronic diseases. This review summarizes current knowledge on the valorization of wheat bran AX in terms of the processing and nutritional properties of AX. Moreover, multiple novel applications of AX in the materials area, including biodegradable food packaging films, delivery of bioactive substances as nanoparticles, and the manufacture of food emulsifiers, are also highlighted to extend the utilization of AX. This review underscores the immense potential of wheat bran AX, advocating for its exploitation not only as a nutritional asset but also as a primary ingredient in advanced materials. The synthesis of nutritional and materials perspectives accentuates the multifaceted utility of wheat bran AX, thereby paving the way for sustainable valorization pathways. By unraveling the latent potential within AX, this paper advocates for the holistic and sustainable utilization of wheat bran in diverse, value-added applications.

Effect of Application of a Bacteria Inoculant and Wheat Bran on Fermentation Quality of Peanut Vine Ensiled Alone or with Corn Stover

To find an effective method for ensiling peanut vine （PV）, fermentation characteristics and nutritional values of PV silage and the mixture of PV with corn stover （CS） silage in a ratio of 1 ： 1 fresh weight, prepared by adding lactic acid bacteria （LAB）, 10% wheat bran （WB） and LAB＋WB at ensiling were evaluated in 2009 and 2010. The fermentation qualities of PV silage ensiled with the LAB and WB additives were improved compared with those of the control （PV ensiled alone）. However, the pH did not decline to the critical level of 4.2, and the nutritional values of the silage were not protected against losses in the LAB and WB addition silages. Ensiling PV in mixture with CS generated optimal moisture content and buffering capacity （BC） of ensiled materials. After adding the LAB and WB additives to mixture silage, especially adding LAB＋WB, the fermentation qualities and nutritional values of the mixture silage were improved significantly （P〈0.05）, and the Flieg＇s score reached to 99. The result suggested that it is a feasible method to ensile the mixed materials of PV with CS by adding LAB and high concentration of water soluble-carbohydrate materials for providing a good fermentation quality of PV silage.

Study on the effect of wheat bran dietary fiber on the rheological properties of dough

The aim of the study was to determine the influence of wheat bran dietary fiber on wheat flour dough rheological properties.In this paper,wheat bran dietary fiber(WBDF)with different levels(0,3%,6%,9%,12%)were added to wheat flour and the characterization of dough rheological properties was conducted by rapid visco-analyzer,farinograph,as well as rotational rheometer.The results from pasting properties showed a gradual reduction in peak viscosity,trough viscosity,final viscosity and setback with increasing WBDF content.At high WBDF concentration,the significant increase of water absorption,formation time as well as weakening degree implied the harder formation of gluten network structure and the competition for water between gluten and WBDF particles.Such conclusion was in line with the findings from dynamic rheology tests,in which the doughs containing WBDF were more sensitive to strain regardless of their rigid and stiff texture.This study revealed vulnerable dough structure induced by WBDF,as well as the strengthened elastic property,elaborating the harmful effects ofWBDF on the rheological properties of doughs.

Effect of wheat bran insoluble dietary fiber with different particle size on the texture properties, protein secondary structure, and microstructure of noodles

This study was conducted to explore how the insoluble dietary fiber(IDF)of wheat bran with different particle size affects the texture properties,water distribution,protein secondary structure and microstructure of noodles.The results suggested that IDF addition increased the cooking loss and decreased the sensory evaluation because of the damage on dough structure,while as the IDF particle size decreased,the sensory score increased from 78.8 to 82.3 and cooking loss decreased from 8.65%to 7.65%,which could be attributed to that small particle-sized IDF limited the damage on protein network structure,decreased the T22 and t-structure,and increased the β1-structure.Moreover,IDF particle size had a significant correlation with protein secondary structures,texture properties and evaluation score of noodles.In conclusion,adding appropriate particle sizewould be an effectiveway of enhancing the nutritional and textural properties of noodles.

Nutritional Quality of Biscuit Supplemented with Wheat Bran and Date Palm Fruits (<i>Phoenix dactylifera</i>L.)

Fruits of date palm (Phoenix dactylifera L.) are consumed throughout the world and are a vital component of the diet in most Arabian countries. The effect of partial replacement of wheat flour with a 1:1 mixture of wheat bran and date palm fruit powder on rheological properties of the biscuit dough was studied. Levels of mixture used were 10%, 20%, 30% and 40%. Dough rheology (farinograph, extensograph properties) and biscuit quality (physical properties, colour, sensory evaluation) were assessed. Results obtained indicated that water absorption gradually increased by increasing the levels of wheat bran: palm date powder, meanwhile mixing tolerance index decreased. Dough stability, which indicates the dough strength, also found to decrease by increasing mixture of wheat bran and date powder (1:1). Furthermore, dough development time gradually increased by increasing the mixture at all levels. It was 6.04 min at level of 40% compared to the control (2.5 min). Extensograph results showed that dough energy and dough resistance to extension and proportional number also increased compared with control sample. The proportional number (R/E) ratios increased largely from 3.20 to 5.27 at the level of 40.0%. Ash and fibre contents gradually increased as the mixture levels increased. However, mineral content progressively increased by increasing the level of date powder in the mixture. Incorporation of wheat bran and date powder mixture decreased the spread of the biscuits from 55.66 to 52.82 mm without change in the thickness of the biscuits. Organoleptic properties revealed that quality of biscuits was acceptable at mixture level of 30%.

Biodegrading Wheat Bran with Agaricus blazei and Its Effects on Intestinal Development Identified with Mice

Agaricus blazei Murill is a well known edible/medicinal mushroom used for immune-nutrient food therapies.The biodegradation of different substrates with this fungus may result in different metabolites and degraded compounds,which may enrich the function of the food therapies.In this study,soluble compounds from the culture of A.blazei grown in liquid media with whole wheat bran and its water filtrate,respectively,were compared.Total soluble sugar,arabinoxylan,protein,and amino acids were significantly higher in the fungal culture resulted from the medium with whole wheat bran （43.54,1.56,0.59,and 2.19 mg mL^-1,respectively） than that from the medium with the bran filtrate （17.28,0.37,0.13,and 1.13 mg mL^-1,respectively）.The biodegraded wheat bran with cultured mycelia was fed to Mus musculus Linnaeus as supplementation or as dietary fiber exclusive ingredient.As non-specific food therapies,feeding effects on mice intestinal development were indicated indirectly in growth performance,intestinal absorption and serum parameters.Compared to feeding uncultured wheat bran,feeding mice with culture mixes of A.blazei resulted in remarkably increase in villus height and villus height/crypt depth ratio,which were increased by 25.4 and 31.0%,respectively,when applied as supplementation,and by 44.3 and 43.4%,respectively,when applied as dietary fiber.These increases are concomitant with the higher level of D-xylose in blood serum about 16.9 and 29.2% as supplementation and dietary fiber,respectively.The results implying that culturing A.blazei with whole wheat bran enhanced extracellular metabolism of the fungus and extensive degradation of wheat bran insoluble fibrous compounds.Furthermore,feeding the culture mix including metabolites and degraded wheat bran improved intestinal villus development,proving the nutritional benefits of the A.blazei mycelial cultures.

Discussion on the Application of LS-DYNA in Superfine Grinding of Wheat Bran

Superfine grinding, involving the fragmentation mechanism of wheat bran cell tissue, is being employed by milling industry. In order to determine the effect of wheat bran cell tissue on the fragmentation mechanism when using superfine grinding,a technical scheme of the nonlinear finite element numerical simulation method based on LS-DYNA is proposed in this paper.The physiological characteristics of wheat bran structural layers including outer pericarp, intermediate layer and aleurone layer are examined first, and then the mechanical properties of wheat bran structural layers and their effects on the super fine grinding process are analyzed. Secondly, the explicit time integration algorithm of LS-DYNA is introduced, and the application feasibility of LS-DYNA in the analysis of wheat bran superfine grinding mechanism is discussed. Finally, the specific application of LS-DYNA in the determination of grinding form and load, the selection and design of the grinding media and the selection of grinding temperature are discussed in detail in the process of superfine grinding for wheat bran cell tissue. The above research provides a theoretical basis for selecting and developing the equipment and technology suitable for wheat bran superfine grinding, and lays a theoretical foundation for enhancing the quality and efficiency of wheat bran superfine grinding.

Effects of insoluble dietary fiber from wheat bran on noodle quality

Benefiting from its favorable effects in promoting intestinal peristalsis,increasing satiety and reducing postprandial blood sugar,wheat bran insoluble dietary fiber(IDF)could be added to noodles to improve the nutrition value of noodle products.However,the addition of IDF usually results in an adverse effect on the quality characteristics of fiber fortified products,leading to unfavorable texture and consumption drop.It was found that IDF could weaken dough characteristics,thereby causing the quality deterioration of noodles,but the mechanism is unclear as yet.This study aimed to investigate the effects of different amounts of IDF on the texture quality and cooking quality of noodles.The water distribution,rheological properties,pasting properties and cooking properties of the noodles were determined by low-field nuclear magnetic resonance(LF-NMR),dynamic rheometer,and rapid visco-analyzer.The results of the LF-NMR showed that the increased IDF in the noodles resulted in a contraction of relaxation time and an increase in the proportion of loosely bound water.At a high amount of IDF,the water absorption and tensile distance of the noodles significantly decreased and the cooking loss rate increased,with a downward trend in peak viscosity,final viscosity and setback values.Moreover,IDF could improve the storage modulus and loss modulus of sheeted dough and enhance the texture of noodles.Furthermore,the correlations between IDF addition amounts and rheological properties as well as cooking properties were analyzed,and the results confirmed that noodles with the IDF amount of 2%–4%had higher nutrition and quality.This study provides the basis for future development and improvement of IDF-enriched health foods.

Quality Characteristics of Gamma Irradiated Beefburger Formulated with Partial Replacement of Beef Fat with Olive Oil and Wheat Bran Fibers

Five beefburger formulations were prepared with substituting beef fat with olive oil and levels of wheat bran and irradiated at doses of 0 and 3 kGy, then samples were refrigerated stored and their quality characteristics were investigated. The results indicated that replacement of beef fat with olive oil and ascending levels of wheat bran in burger batter significantly decreased their contents of total lipids and saturated fatty acids, while increased their contents of dietary fibers, unsaturated fatty acids and the ratios of unsaturated and polyunsaturated fatty acids to the saturated ones. Moreover, significant improvements were observed in the cooking yield and moisture and fat retention of samples, proportionally to the added wheat bran, and both raw and cooked burger samples showed a high sensory acceptability. Irradiation of samples effectively inactivated Staphylococcus aureus, Salmonella and enterobacteriaceae and significantly reduced the counts of mesophilic and psychrophilic bacteria as well as molds and yeasts without any adverse effects on the quality characteristics of samples. Thus, reducing beef fat levels with the addition of olive oil and wheat bran produced a highly acceptable beefburger products with improved nutritional content as well as improved cooking and binding properties, while irradiation improved their microbiological quality.

Sorption equilibrium moisture and isosteric heat of Chinese wheat bran products added to rice to increase its dietary fibre content

More and more people concern about supplementing dietary food with wheat bran to increase fibre content,but there has been little study of the sorption isotherms and isosteric heats of wheat bran fibre products,which are important to the quality and storage durability of such commodities.This study collected equilibrium moisture content(EMC)and equilibrium relative humidity(ERH)data on six Chinese wheat bran products via the static gravimetric method and analysed their sorption isosteric heats.Results showed that all six wheat bran products had sigmoidal isotherms.The data were best fitted by polynomial,modified GAB,modified Oswin,and modified Halsey models.The relative safe moisture contents of the six wheat bran products were 12.20%–13.86%wet basis(w.b.).The heat of vaporization of wheat bran products approached the latent heat of pure water at around a moisture content(MC)of 22.5%and approximately 2450 kJ/kg.A process of extrusion and ultrafine grinding reduced the solid surface area and sorption isosteric heats of the monolayer,multilayer and condensed water regions in the wheat bran products.In the temperature range of 10–37℃,the EMC of sorption in monolayer,multilayer and condensed water regions decreased with increasing temperature.The milled rice to which 1%–3%200-mesh wheat bran product was added maintained its texture when made into cooked rice and its thermomechanical properties when made into rice dough.After processing by extrusion and ultrafine grinding,wheat bran products have a lower solid surface area and lower monolayer water content(Mm)and sorption isosteric heat values.Some 3%200-mesh wheat bran product can be added to cooked rice for increasing its fibre content and making it more nutritious.

Extraction of Dietary Fiber from Wheat Bran and Effects of Its Additives on Viscosity-elasticity of Noodle Dough

[ Objective] The aim was to study the optimum extraction condition of dietary fiber of wheat bran and to discuss its influence on viscosity-elasticity of noodle dough with added extracts. [ Methed] Influences of a-amylase, alkaline concentration, alkaline hydrolysis time and temperature on water holding capability and swelling capacity of dietary fiber were evaluated using single-factor test and orthogonal test. Effects of added dietary fiber from wheat bran on dough absorption ratio, rupture stress of dough and creep resistance were studied. [ Result] When the hydrolysis condi-tions of wheat bran were 0.4% a-amylase at 75 ℃ for 60 rain, further alkaline conditions were 5% sodium hydroxide for 60 min at 65 ℃, dietary fi-ber exhibited fine water holding capability and swelling capacity. The addition of 3%-5% dietary fiber from wheat bran into dough had little influence on the water absorption ratio of noodle, rupture stress of dough, creep resistance and can make functional noodle with rich dietary fiber from wheat bran. [Coonclusion] The study provided reference for the comprehensive utilization of wheat bran and development of functional product.

Microstructure observation of multilayers separated from wheat bran

In order to understand more clearly the morphology of the structural layers of the soft and hard wheat bran to understand the effect of mechanical force on the wheat grain,we observed the microstructure of each layer of the wheat bran from soft and hard mature wheat.Based on the differences in mechanical properties and water permeability of each wheat bran layer,the mature wheat grains were alternately treated under cold and heat conditions and separated by manual dissection.The microstructure of each layer of wheat bran from soft and hard mature wheat was determined by optical and fluorescence microscopy.Seven different structure layers were observed by optical microscopy,named them as epidermis,epicarp,cross cells,tube cells,testa,nucellar layer,and aleurone layer.All the layers of the outer bran of wheat grains were separated,except for the tube cells layer.The autofluorescence imagings of five layers were obtained.It was found that the morphology of the structural layers of the soft and hard wheat bran did not differ much,except for the aleurone layer.The aleurone layer of soft wheat bran was significantly different from that of the hard wheat bran,which is fuller and denser compared to soft wheat.In this study,more aleurone grains were lost in the aleurone layer obtained by the outsidein peeling method.The mastery of the morphology of each structural layer of the bran helps us to quickly quantify the degree of peeling of wheat milling,and to make immediate adjustments to the process.At the same time,we understand that the contents of the aleurone cells have different binding strengths with the nucellar layer and the starchy endosperm.The paper is instructive to deep investigation of wheat milling mechanism and product process refinement.

Antioxidant Activity of Pigment Extracted from Green-Wheat-Bran

The anthocyanin pigment extracted from green-wheat-bran was studied to identify its antioxidant activity.The antioxidant activities of the pigment were evaluated by anti-lipid peroxidation,total antioxidant activity （TAA）,superoxide anion radical scavenging activity （SARSA）,active oxygen scavenging activity （AOSA）,and DPPH （1,1-diphenyl-2 picrylhydrazyl free radical） radical scavenging activity.The results showed that the pigment had higher antioxidant activity and TAA,SARSA,AOSA and DPPH.scavenging activities at a certain concentration than Vc （antiscorbutic vitamin,vitamin C）,and the capacity increased with the increase of pigment concentration.Its TAA was 51.06 U mL-1,1.73 times of Vc,and SARSA 18 025.21 U mL-1,2.26% higher than Vc,and AOSA 3 776.31 U mL-1,1.24 times of Vc.As to the DPPH.scavenging activity of the pigment,there was a trend that higher concentration performed higher activity significantly improved with the company of Vc.The pigment showed significant antioxidant activities evaluated by different assays.Results will provide a better understanding on antioxidant activity of green wheat and allow the screening or breeding of green wheat varieties with higher antioxidant activity for food processing.

A Combination of Wheat Bran and Vegetable Oils as Feedstuff in Laying Hens’Diet:Impact on Egg Quality Parameters

Wheat bran (WB) is an important side product of the milling industry and plays an increasing role in animal feeding. Despite its nutritional value, its application is limited as a result of its pronounced fiber content. Taking into account the potential use of WB supplementation in feed for laying hens thereby replacing human edible foodstuffs, the influence of different WB levels (0 g·kg-1, 75 g·kg-1, and 150 g·kg-1) combined with sunflower or rapeseed oil on egg quality was studied. Among the egg-related quality parameters investigated, eggshell cleanliness, shell rigidity, egg weight, haugh units, yolk and albumen mass, color, pH value, dry matter, crude protein, crude ash, fatty acid spectrum, cholesterol and α-tocopherol of the yolk were monitored. No negative effect of WB supplementation was observed in terms of egg weight, shell weight, albumen weight, yolk weight, haugh unit, shell thickness and eggshell breaking strength. However, certain parameters (i.e. α-tocopherol content, Σn-3 PUFA) were enhanced by feeding 75 g·kg-1 and 150 g·kg-1 WB. The use of WB (75 g·kg-1 and 150 g·kg-1) had no negative effect on egg quality and can, therefore, be recommended for laying hen diets up to 150 g·kg-1. Additionally, the application of rapeseed oil high in Σn-3 PUFA resulted in yolks exhibiting a low Σn-6 PUFA/Σn-3 PUFA ratio.

Digestibility of Sheep Ration Containing Different Levels of Native Grass Hay and Concentrate Mixture of Wheat Bran and Dried Food Left over

The experiment was carried out at Mekelle University livestock farm, Tigray, Ethiopia. 12 male yearling Highland sheep with an average live weight of 20 + 2.5 kg (mean ± standard deviation) were used in the experiment. The objective of the study was to investigate the effect of digestibility of sheep ration containing different levels of roughage and concentrate mixture on performance of highland sheep. Food left over was collected from Mekelle University student cafeteria and dried with sun light for 3 - 4 days. The experimental design was a randomized complete Block design (RCBD) with four treatments and three replications. The experimental animals were grouped into three blocks based on their initial live body weight, which was determined by weighing after overnight fasting. The experiment was carried out for 15 days including 5 days of adaptation period and 3 days of adaptation and harnessing (fecal bags). At the end of the feeding trial, digestibility trial was carried out for seven consecutive days. There was significantly higher (P 0.05) total DM intake in the supplemented group than in the control treatment. Digestibility of DM and OM were non-significance (P > 0.05) for all treatments. Generally, the present study indicated that supplementation of Tigray highland rams with concentrate mixture had an effect on performance of sheep and the effects were relatively more pronounced on rams supplemented with the highest level of concentrate mixture.

Feasibility of Wheat Bran as the Sole Nutrient Source of Platymonas helgolandica var.tsingtaoensis

The growths of algae under different concentrations and treatments of wheat bran were studied in order to investigate the feasibility of wheat bran as the sole nutrient source of Platymonas helgolandica var.tsingtaoensis.The results showed that adding wheat bran directly to the algal fluid can promote algal growth.The algal growth was inhibited for the first 10 d and accelerated dramatically thereafter.For the comparison between the algae whose growth was modified by using wheat bran packed in a teabag or boulting cloth bag,and that by using loose wheat bran only,results showed that,at the same concentration,the algae grew faster and without lag phase when the wheat bran was packed in a teabag or a boulting cloth bag than when loose wheat bran was used only.In addition,when the wheat bran was packed in a boulting bag,the algal growth was slightly better than when the wheat bran was packed in a teabag.When the concentration of wheat bran ranged from 0.5 to 4 g/L,the cell density rose with the increase of the concentration of the wheat bran,however,the algal growth was inhibited completely at 8 g/L.At a concentration of 4 g/L,the fast-growth phase of the algae with the wheat bran aerobic pretreatment started 6 d earlier than that with wheat bran packed in a teabag,whereas there was no significant difference between them in final cell density.In terms of cell growth,the algal growth at 1 g/L wheat bran was close to that at f/2 medium during the experimental period.The study showed that it is feasible to use wheat bran as the sole nutrient source for the culture of Platymonas helgolandica var.tsingtaoensis.

Effect of Acid Treatment on the Saccharification of Wheat Bran Cellulose

[ Objective] The aim was to improve the saccharification of wheat bran cellulose. [ Method] Taking the wheat bran as raw materials, and using orthogonal method, the effects of acid concentration, temperature, times and substrate concentration on the saccharification were investigated. [ Result] The influence of temperature on the acid treatment of the sacchadfication of wheat bran cellulose was significant. Influences of acid concentration on the hydrolysis were distinct. Influences of time and substrate concentration were insignificant. The optimal pretreatment conditions were 1.5% of sulfuric acid concentration and 0. 067 g/ml of substrate concentration at 100℃ in three hours. Under this condition, the sugar concentration was 38.137 mg/ml, and the hydrolysis rate reached 51.485%. [ Conclusion] The study improved the saccharification of wheat bran cellulose, which provided theoretical basis for the application of wheat bran industrial process.

Optimization and pharmacodynamic evaluation of stir-frying with bran for Tangshen processing

Background:Traditional Chinese medicine requires special processing before it can be effectively used for clinical treatment of diseases.In particular,Tangshen stir-fried with wheat bran smoke has been found to enhance the function of the stomach and spleen.However,there is limited research on the technology and pharmacodynamic effects of Tangshen fried with bran.Therefore,the objective of this article is to optimize the method of stir-frying with bran for Tangshen processing and to compare the anti-fatigue and hypoxia-resistance effects of Tangshen before and after bran-frying.Methods:The response surface methodology was utilized to optimize the frying temperature,frying time,and the bran-to-Tangshen ratio,using lobetyolin as the indicator.The swimming time of mice and the levels of blood urea nitrogen,lactate dehydrogenase,and blood glucose in fatigued mice were compared before and after Tangshen was fried with bran.Additionally,the hypoxic resistance ability of Tangshen before and after bran-frying was determined through normobaric hypoxia test and sodium nitrite poisoning test.Results:The optimal bran-frying conditions for Tangshen processing were determined as:frying temperature of 167°C,frying time of 2.67 min,and the bran-to-Tangshen ratio of 50:100.Pharmacodynamic analysis results indicated that Tangshen significantly increased the GLU content(P<0.01)and significantly reduced the LDH content(P<0.01)both before and after bran-frying.While both traditional and new bran-frying methods significantly increased the content of muscle glycogen(P<0.05),the optimized method in this study also significantly elevated the content of liver glycogen(P<0.05).The traditional method significantly prolonged the survival time of mice from sodium nitrite poisoning(P<0.05).Conclusion:The response surface model proved to be highly effective in optimizing the stir-frying process with bran for Tangshen processing.The results of this study indicate that Tangshen possesses anti-fatigue and hypoxia-resistance effects both before and after bran-frying,with bran-fried Tangshen exhibiting significantly stronger effects.

超声法与微波法提取小麦麸皮总黄酮的工艺及抗氧化活性比较

采用超声法和微波法提取小麦麸皮总黄酮,通过单因素试验和正交试验确定最佳提取工艺,并比较这两种方法的提取效果及总黄酮的抗氧化活性。结果表明,超声提取法的最佳条件为料液比1∶14 g/mL、70%乙醇、提取25 min,总黄酮提取率为1.082 mg/g。微波提取法的最佳工艺为料液比1∶18 g/mL、80%乙醇、提取40 s,总黄酮提取率为1.522 mg/g。微波法提取率明显高于超声法。在试验浓度范围内,超声法提取的总黄酮对DPPH自由基的清除能力较强,显著优于VC和微波法。

炮制辅料麦麸的应用历史沿革与特色研究

麦麸作为炮制辅料历史悠久,应用广泛,经过各地区炮制流派对传统炮制方法的传承与发展,形成了独特的地域特色。基于辅料麦麸适用炮制方法种类繁多、沿革跨度较大,现借助数据库和文献挖掘技术对传统医药典籍、地方医药典籍中有关辅料麦麸的炮制方法及应用药物进行整理,分析辅料麦麸炮制方法的历史沿革、应用趋势及特点,以期为辅料麦麸的继承与发展,筛选麦麸制法特色饮片品种、炮制工艺及质量标准,阐释其科学内涵提供参考依据。