淀粉-脂肪酸改性高岭土的制备及其在包装纸上的应用

To improve the bondability between clay filler and lignocellulosic fiber,Kaolin clay particles were modified using a starch-fatty acid complex method.The coating efficiency of starch on clay particle surfaces was investigated by measuring the dissolved starch in the supernatant.The experimental results indicated that more than 98%of the applied starch was precipitated onto the surface of the filler,and the resulting starch-fatty acid-clay composites had relatively good resistance against moderate shear force.The morphology,particle size,andζpotential of the starch modified filler were also determined with scanning electron microscopy,Malvern particle size analyzer,and Malvern Zetasizer,respectively.An aqueous slurry of linerboard pulp containing 5～15wt%modified fillers was used for handsheet preparation,and the effects of the addition of modified filler on the paper properties were studied.At a dosage of 10%of the modified filler(based on filler), the retention of the filler was higher than 75%.The strength properties of paper with starch modified fillers were improved by approximately 15%when compared against those of paper with unmodified fillers.     

Sensory Evaluation of Flavored Soy Milk-Based Yogurt： A Comparison between Jordanian and Malaysian Consumers

Soy yogurt has gained significant popularity due to its nutritional health benefits. The objectives of this study were to develop flavored yogurt from soybean milk with reduced soy aftertaste by the addition of 30% （wt/wt） strawberry or orange jam in conjunction with a lactic acid fermentation. Soy milk-based yogurt products were assessed for microbial quality and for acceptability by a panel of Jordanian and Malaysian consumers. Sixty-one individuals, of whom 75.4% （n = 46） were Jordanian and 24.6% （n = 15） were Malaysian, evaluated the plain and flavored soy milk-based yogurt. The overall acceptability of orange and strawberry soy yogurt was rated significantly higher than plain soy yogurt. In general, the orange and strawberry soy yogurt received higher sensory ratings from Malaysian than Jordanian consumers. In addition, formulations with orange jam received higher scores than those flavored with strawberry. Shelf life tests showed that soy yogurt was acceptable for at least 8 d without perceptible spoilage. Therefore, the approach used yielded flavored products with better acceptability and improved sensory attributes, including decreased intensity of off flavor, with suitable shelf life at 4 ℃.     

Conservation of Leaves of a Medicinal Plant of Western Algeria （Pistacia atlantica）

In our context, and in the goal to valorize the Pistacia atlantica species Desfthat grows spontaneously in Algeria occidental except the coastline, and that is used by the nomadic populations in their daily consumptions, we are thinking about drying its leaves. Here, the biochemical analysis of dried leaves ofPistacia atlantica is determined, the sorption is other ms are of great importance in the food industry, especially in the drying; the sorption isotherms of pistachio leaves were measured by the gravimetric method at three temperatures 40, 50 and 60 ℃. The equilibrium was achieved after eight days for desorption and seven days for adsorption with water activity ranging from 5% to 90%. Only the GAB and Peleg models were found to be the most suitable for describing the sorption curves. The isosteric heat of sorption of Pistacia atlantica leaves decreases with an increase in moisture content and was found to be an exponential function of moisture content for adsorption and desorption. The pistachio leaves could be considered as a rich natural source of valuable nutriments （carbohydrates, proteins and lipids）; lipid fraction is equal to 2.25%; proteins are the second macronutriment that predominates in these sheets： 4.35%; accordingly carbohydrates content was about 25.77%.     

Chemical Compositions and Antioxidant Activity of Northern Thai Woods Aging Wine

Wine aging for 120 days was prepared by using luna nut （Lepisanthesfruticosa Leenh.）, Longan （Dimocarpus longan Lour.）, black poum （Cleistocalyx nervosum var. paniala）, neem （Azadirachta indica）, drumstick （Moringa oleifera Lam.） and oak （Quercus sp.）. The taste examination was done by 50 sensory examiners in order to evaluate the organoleptic quality of wine samples. The results showed that the highest score of organoliptic quality of wine aging with Longan woods relating to oak wood. Therefore, Longan wood is the most acceptable can used for wine aging process. The qualitative analysis for some volatile aroma of the two highest score wood aging wine was carried out by gas chromtography-mass spectrometer （GC-SPME） technique, equipped with a Flame lonisation Detector （FID） detector and a DB-WAX capillary column with helium as a carrier gas. The oven temperature was kept at 40 ℃ for 7 min followed by increasing to 230 ℃ with the rate of 3 ℃/min. The result showed the present β-caryophillene, humulene and eugenol in Longan wood wine while eugenol and ethyl octanoate were found in case of drumstick wood wine. The antioxidant activity of all wood aging wine was determined by DPPH scavenging technique. Wine aging with Longan used showed the test result with 1.62% v/v for EC50.     

Effect of Glutathione and Storage Time on Rheological Properties of Per-proofed Frozen Dough

The effect of reduced glutathione （GSH） on fresh and pre-proofed frozen dough rheological properties were investigated using dynamic stress rheometry and small scale extensibility with the addition of three levels （80×10^-6, 160 ×10^-6 and 240× 10^-6 GSH） and six storage times （0 and 1 day, 2, 4, 6 and 8 weeks）. Three relaxation times （1, 13 and 26min） after loading the dough in the rheometer were used to determine storage （G＇） and loss （G＂） moduli. Correlations for G＇ （r=-0.678 and 0.622 at 0.05, and 10Hz, respectively） and G＂ （r=0.699, and 0.690 at 0.05, and 10Hz, respectively） were observed with the area under the extension curve at 26 min relaxation time. The addition of GSH to fresh dough reduced G＇ （16.4% to 55.9%） and G＂ （13.7% to 52.2%）. Freezing and frozen storage caused increase in G＇ and G＂. The addition of GSH reduced dough strength indicated by the reduction in maximum resistance to extension （Rmax） and the ratio of maximum resistance to extensibility（Rmax/E）. The reduction in Rmax across all relaxation times ranged from 16.2% to 59.4%. An increase in dough extension （E） was observed with 240 ×10^-6 GSH at all frozen storage and rest period times. Addition of GSH caused an increase of liquid phase （30.6% to 35.3%） in fresh dough and frozen dough （10.3% to 20.7%） after one day frozen storage. Negative correlations of water content in the solid phase with dough extensibility and area under the extensibility curve were found （r=-0.594 and -0.563, respectively, p 〈 0.001）. This suggests a loss of dough extensibility and strength as the water holding capacity of the dough components changes during frozen storage.     

Optimization on Pretreatment and Enzymatic Hydrolysis of Sugarcane Trash for Ethanol Production

The present study was conducted for the optimization of pretreatment and enzymatic hydrolysis of lignocellulosic biomass （sugarcane trash）, which is a renewable resource for the production of bioethanol. The pretreatment and enzymatic hydrolysis conditions including alkali （NaOH）/dilute acid （H2SO4）, substrate and chemical concentration for pretreatment, enzyme dosage, pH, temperature and substrate concentration for hydrolysis were varied and evaluated for sugar and ethanol production at the end. The optimum condition was accomplished using 15% w/v DS of 0-2 mm sugarcane trash in size of particle. It was pretreated with two steps of 2% w/v NaOH autoclaving followed by 2% w/v H2SO4 autoclaving with washing step after pretreatment. An enzymatic hydrolysis was then performed using 15% w/v DS pretreated substrate, hydrolyzed with cellulase 50 filter paper unit （FPU）/g DS at 50 ℃ and pH 5. After incubating at 160 r for 48 h, 117.16 g/L reducing sugar was obtained. The achieved sugar after enzymatic hydrolysis was finally fermented to ethanol by Saccharomyces cerevisiae TISTR 5596, with concentration of 48.17 g/L ethanol or yield 0.509 g/g reducing sugars which was equal to 99.81% of theoretical yield.     

Utilization of Yellowfin Tuna and Red Snapper Roe Protein Concentrate as Emulsifier in Mayonnaise

Roes of yellowfin tuna （Thunnus albacares） and red snapper （Lutjanus champecanus） are considered as abundant and underutilized by-product in Indonesia. The production of roe protein concentrate （RPC） is expected to increase the economic value and potency of their usage. Tuna and red snapper RPC was defatted using etano195% with one, two, three and four times of repetition. Both RPC made with four times repetition of defatting had the highest protein content （79.90% and 80.72%）, showed high emulsion activity （97.46% and 99.62%） and emulsion stability （97.10% and 99.48%）, and decreased the interfacial tension of 51% and 55.9%, respectively. Mayonnaise was made with 0, 25, 50, 75 and 100% substitution level of each RPC with four times repetition ofdefatting. The physical, chemical and organoleptic properties of mayonnaise were studied. The best mayonnaise formulation was obtained from 50% substitution level of tuna and red snapper RPC. Mayonnaise with tuna and red snapper RPC had good viscosity （5,920 cPs and 5,845 cPs）, high emulsion stability （90.5% and 91.73%） and small fat globule size （±2.5 lam and ± 2.25 lam）, respectively. These mayonnaises also showed high score of spreadability and low intense of fishy odor. However they still had quite strong of fishy flavor based on scoring test.     

Study on the structure and properties of modified silk with ultraviolet absorbent北大核心CSCD

The silk fiber has an irreplaceable position in textile fibers and related silk fabrics have the advantages of light and airy texture good moisture absorption and breathability comfort in wear etc. It is also widely used in other fields such as the biomedical sector. However silk also has its own limitations poor light resistance and susceptibility to ultraviolet light especially the ultraviolet light of 290-400 nm wavelength in daylight such as under which condition it is prone to yellowing and photodegradation. The yellowing of silk is due to the photo-oxidation of tyrosine and tryptophan in silk protein under the action of ultraviolet light from sunlight and due to the production of yellow substances which affects the whiteness of silk. In addition from the molecular structure of silk most of the amino acids susceptible to UV light are distributed in the amorphous region. As the amorphous region is affected the structure of the crystalline region is also gradually relaxed the local degradation begins and the silk protein macromolecule chain is cleaved which leads to the decrease of the mechanical properties of silk fibers and accelerates the aging of silk fibers and fabrics. Therefore it is necessary to modify the silk products outside the anti-purple line. The current methods used to modify silk are mostly for post finishing modification including coating impregnation and chemical grafting methods but these methods often affect the original color or feel of the fabric and the durability of the modified effect is also poor. The feeding method is a green method to obtain modified silk by spraying mulberry leaves or artificial feed mixed with modifier which is ingested by silkworm and transferred to silk gland. In this study five aminobenzene UV absorbers were used as exogenous additive food for silkworms. The effect of molecular polarity on the transport of modifiers to silk glands was investigated and their effects on silkworm development and silk structural properties were studied. It was found that the aminobenzene UV absorbers were more easily transferred to the central silk gland silk glue and less to the posterior silk gland (fibroin). 4-dimethylaminobenzoic acid was found to be the highest in the posterior silk gland with a content of 3. 27 μg / strip. The cocoon width and cocoon quality of this group were significantly lower than those of the control group and the silk gum content was increased when this group was used as the study object. Compared with the control group the relative content of β-folded structure and crystallinity of the silk in the addition feeding group decreased slightly. The silkworm silk in the feeding group showed a certain UV absorption ability. After 330 h UV irradiation the breaking strength and elongation of the control group decreased by 48. 95% and 43. 52% respectively while those of the feeding group decreased by 42. 03% and 34. 18% respectively. In this paper UV absorbers were added to silkworms to obtain modified silk mainly focusing on the transfer of the modifier to the silk gland and the structural properties of the modified silk only for the most UV absorbers to enter the silk gland of the posterior group of silk. Other properties of the modified silk such as washing resistance have not been studied and some more in-depth studies are required. For instance it needs to be studied in depth for the limited absorption of exogenous additives by silkworms additive food's being not always absorbed by silkworms and transferred to the silk gland and the mechanism of action between the additive food and silk protein after the former's entering the silk gland. © 2022 Authors. All rights reserved.     

Eco-friendly PVA/Kaolin Clay Coating for Barrier Paper

The resistance of wood-fiber paper to water, grease, and water vapor is usually attained by immersing the base paper in hydrophobic oil, laminating with a plastic or metal film, or the application of a barrier coating. Oil impregnation and the addition of films may make the paper difficult to recycle or persistent in the environment owing to their strong binding force and nondegradability. Environmental concerns have attracted worldwide attention to eco-friendly barrier coatings. In this study, degradable polyvinyl alcohol(PVA) and kaolin clay pigment were used to prepare coatings that were applied to a base paper. By measuring the barrier properties of the coated paper, including the water absorptiveness(Cobb60 value), Hercules sizing degree, oil resistance(Kit rating), and water vapor transmission rate(WVTR), an optimal coating formulation and process were proposed. To examine the barrier mechanism of the PVA/kaolin clay coating, we characterized the coating microstructures using a scanning electron microscopy(SEM) and a mercury porosimeter. The results showed that the Cobb60 value and water vapor transmission rate of the coated paper decreased by 61.4% and 98.6%, respectively, compared with the base paper, for a pre-coating weight of 0.98 g/m~2 and a top-coating weight of about 3.23 g/m~2. Furthermore, the Hercules sizing degree rose by a factor of 337.2, while the oil resistance(Kit rating) increased from 0 to 12. The optimum drying temperature for a wet coating layer was found to be 170℃, and the optimum weight ratio of PVA to kaolin clay in the coating was determined to be 50∶50. It was assumed that the PVA/kaolin clay coating improved the smoothness of the paper considerably and decreased the pore size by filling the pores on the paper surface and forming an even film, thus enhancing the paper barrier performance. The coated paper also exhibited good repulpability.     

Determination of Antioxidant and Cytotoxic Activities of Red Seaweed, （Gracilaria manilaensis） against Different Cancer Cell Lines

Antioxidants play an important role in inhibiting and scavenging free radicals in human, providing protection against cellular damage in relation to cancer initiation. Seaweeds have been proved to have high antioxidant activity. Thus, this research was carried out to determine the antioxidant and anticancer properties of edible red seaweed, Gracilaria manilaensis （Gracilariales, Rhodophyta）. The extracts were prepared by Soxhlet extraction using organic solvents with different polarities. The antioxidant activities of extracts were determined in terms of their flee radical scavenging activity （RSA IC50） and total phenolic content （TPC）. The cytotoxic activity of extracts were tested against human ovarian cancer cell line （Caov-3）, human breast cancer cell line （MDA-MB-231 and MCF-7）, human cervical cell line （HeLa）, mouse fibroblast cell line （L929） and Madin-Darby canine kidney （MDCK） and the cell viability after 72 h incubation was determined by methylene blue assay. The findings showed that acetone extract has the lowest DPPH IC50 value followed by ethyl acetate extract. Both extracts also showed high values of TPC. Dichloromethane extract had the strongest cytotoxic on MDA-MB-231 （53.90 μg/mL ± 5.59 μg/mL） and HeLa （95.50 μg/mL）. While, acetone and ethyl acetate extracts were cytotoxic on MCF-7 （66.07 μg/mL） and Caov-3 （69.67 μg/mL ± 13.94 μg/mL）. It could be concluded that the antioxidant and cytotoxic activities of G. manilaensis were influenced by the types of solvents used and thus had a potential to develop as a cancer chemoprevention or anticancer agent against selected cancer.     

外源脂肪酶对国产小麦面包粉品质的影响

通过流变学试验、面包烘焙试验和面包芯质构测试,探讨了脂肪酶对国产麦面包粉品质的影响。试验表明,与对照组相比较,在添加脂肪酶后,面团的流变学性质、面包品质都得到明显改善。由烘焙试验及质构测试结果可知,脂肪酶对面包制品的内部组织结构,面包芯柔软度等指标都有较好的改良作用。本试验条件下,添加脂肪酶30×10-6为最适添加量。     

Physicochemical Properties and Consumer Acceptance of Wheat-Germinated Brown Rice Bread during Storage Time

Abstract: Selected physicochemical properties and consumer acceptance of bread prepared from composite flour (wheat:germinated brown rice:germinated glutinous brown rice flours at 60:30:10 ratio) were evaluated during storage for 0, 3, and 5 d, and compared with wheat bread (0 d, control). During storage, color profiles and water activity (from 0.947 to 0.932) of crumbs of composite flour breads slightly changed, but moisture content drastically decreased along with increasing crumb hardness (from 4.16 N to 10.37 N). Higher retrogradation in bread crumb was observed particularly for 5-d stored bread (ΔH = 2.24 J/g) compared to that of the fresh composite bread and the control (ΔH = 0.70 and 0.51 J/g, respectively). Mean (n = 116) overall liking score of the fresh composite flour bread (0 d) was slightly lower than that of the control (7.1 compared with 7.6 based on a 9-point hedonic scale). At least 76% of consumers would purchase the fresh composite flour bread if commercially available. Breads were differentiated by textural (moistness, smoothness, and softness) acceptability with canonical correlation of 0.84 to 0.87. The signal-to-noise ratio values of the 5-d stored breads were lower than the control, due mainly to the non-JAR (not-enough) intensity responses for moistness, smoothness, and softness; the mean drop of liking scores for these attributes ranged from 2.42 to 2.98. Flavor acceptability and overall liking were factors influencing consumers’ purchase intent of composite flour breads based on logistic regression analysis. This study demonstrated feasibility of incorporating up to 40% germinated brown rice flour in a wheat bread formulation. Practical Application: Our previous study revealed that flours from germinated brown rice have better nutritional properties, particularly gamma-aminobutyric acid (GABA), than the nongerminated one. This study demonstrated feasibility of incorporating up to 40% germinated brown rice flour in a wheat bread formulation. In the current U.S. market, this type of bread may be sold as frozen bread that would have a longer shelf life, or may be supplied as a food-service product that would be made-to-order or made fresh daily as currently practiced in some major grocery stores.     

Germination Conditions Affect Selected Quality of Composite Wheat-Germinated Brown Rice Flour and Bread Formulations

Abstract: Brown rice has been reported to be more nutritious after germination. Germinated brown rice flours (GBRFs) from different steeping conditions (in distilled water [DI, pH 6.8] or in a buffer solution [pH 3] for either 24 or 48 h at 35 °C) were evaluated in this study. GBRF obtained from brown rice steeped at pH 3 for 48 h contained the highest amount of free gamma aminobutyric acid (GABA; 67 mg/100 g flour). The composite flour (wheat-GBRF) at a ratio of 70 : 30 exhibited significantly lower peak viscosity (PV) (56.99 – 132.45 RVU) with higher alpha-amylase activity (SN = 696 – 1826) compared with those of wheat flour (control) (PV = 136.46 RVU and SN = 1976). Bread formulations, containing 30% GBRF, had lower loaf volume and greater hardness (P < 0.05) than the wheat bread. However, the hardness of bread containing 30% GBRF (except at pH 6.8 and 24 h) was significantly lower than that of bread containing 30% nongerminated brown rice flour (BRF). Acceptability scores for aroma, taste, and flavor of breads prepared with or without GBRFs (30% substitution) were not significantly different, with the mean score ranging from 6.1 (like slightly) to 7 (like moderately). Among the bread formulations containing GBRF, the one with GBRF prepared after 24 h steeping at pH 3 had a slightly higher (though not significant) overall liking score (6.8). This study demonstrated that it is feasible to substitute wheat flour with up to 30% GBRF in bread formulation without negatively affecting sensory acceptance. Practical Application: Our previous study revealed that flours from germinated brown rice have better nutritional properties, particularly gamma-aminobutyric acid (GABA), than the nongerminated one. This study demonstrated feasibility of incorporating up to 30% germinated brown rice flour in a wheat bread formulation without negatively affecting sensory acceptance. In the current United States market, this type of bread may be sold as frozen bread which would have a longer shelf life. Further study is thus needed.     

Response Surface Methodology in the Development of Rice Flour Yeast Breads: Sensory Evaluation

Yeast breads were developed from rice flour (80%) and potato starch (20%). Using sensory measurement from a trained panel, response surface methodology (RSM) was applied to find carboxymethylcel-lulose (CMC), hydroxypropylmethylcellulose (HPMC), and water level combinations for gluten-free breads from three different rice flours. Formulations resulted in rice breads that met wheat bread reference standards for moistness, cohesiveness, yeasty flavor, adhesiveness, aftertaste, top crust and crumb color, cell size uniformity and predominant cell size. Medium grain rice flour breads met more sensory reference standards than long grain rice flour breads.     

Discrimination of Volatiles of Refined and Whole Wheat Bread Containing Red and White Wheat Bran Using an Electronic Nose

Abstract: The principal objective of this study was to evaluate the capability of electronic (E) nose technology to discriminate refined and whole wheat bread made with white or red wheat bran according to their headspace volatiles. Whole wheat flour was formulated with a common refined flour from hard red spring wheat, blended at the 15% replacement level with bran milled from representative samples of one hard red and 2 hard white wheats. A commercial formula was used for breadmaking. Results varied according to the nature of the sample, that is, crust, crumb, or whole slices. Bread crust and crumb were completely discriminated. Crumb of whole wheat bread made with red bran was distinct from other bread types. When misclassified, whole wheat bread crumb with white bran was almost invariably identified as refined flour bread crumb. Using crust as the basis for comparisons, the largest difference in volatiles was between refined flour bread and whole wheat bread as a group. When refined flour bread crust was misclassified, samples tended to be confused with whole white wheat crust. Samples prepared from whole bread slices were poorly discriminated in general. E‐nose results indicated that whole wheat bread formulated with white bran was more similar in volatile makeup to refined flour bread compared to whole wheat bread made with red bran. The E‐nose appears to be very capable to accommodate differentiation of bread volatiles whose composition varies due to differences in flour or bran type. Practical Application: Consumer preference of bread made using refined flour in contrast to whole wheat flour is partly due to the different aroma of whole wheat bread. This study used an electronic nose to analyze bread volatiles, and showed that whole wheat bread incorporating white bran was different from counterpart bread made using red bran, and was closer in volatile makeup to “white” bread made without bran. Commercial millers and bakers can take advantage of these results to formulate whole wheat flour with brans of preferred type in order to foster increased consumption of whole wheat products which confer many favorable health benefits.     

品质改良剂对复合杂粮面包粉流变学特性的影响

以营养优化后的复配杂粮面包粉为原料,选择谷朊粉、硬脂酰乳酸钠（sodium stearoyl lactylate,SSL）、黄原胶及瓜尔豆胶为品质改良剂,通过单因素试验研究4 种品质改良剂对杂粮面包粉流变学特性的影响,在此基础上通过响应面分析试验,以面团综合得分为响应值,得出复合改良剂的最佳配方为：1 000 g杂粮面包粉（杂粮粉占比34%）为基重,谷朊粉3.77%、SSL 0.35%、黄原胶1.08%、瓜尔豆胶0.35%。各因素对杂粮面包粉综合评分的影响大小为：黄原胶添加量＞谷朊粉添加量＞瓜尔豆胶添加量＞SSL添加量。添加复合改良剂后杂粮面包粉的稳定时间由4.7 min上升到14.2 min,形成时间由3.9 min上升到了13.3 min,粉质指数从56上升到192。复配杂粮面包粉流变学特性有很大程度改善,达到制作杂粮面包的粉质要求。     

脱脂对小麦馒头品质的影响

脂类在小麦粉中含量极低,但对食品品质有很大的影响.选取6个不同品种的小麦,用氯仿脱脂,并分别制作馒头.通过馒头的TPA测定、馒头老化以及馒头表观形态和内部结构的变化来分析脂类对馒头品质的影响.结果表明:脂类对馒头品质的影响因小麦品种的不同而有所差异.脱脂后,弱筋小麦粉的馒头制品与对照相比,馒头体积增大,比容增加,硬度、...     

糯小麦粉添加量对配粉流变学特性及馒头品质的影响

将糯小麦粉与普通小麦粉进行梯度配粉,研究不同糯小麦粉添加量对配粉糊化黏度、粉质特性和面团流变学特性的影响;采用质构和感官评价相结合的方法评价其对馒头品质的影响,确定合适的糯小麦配粉比。结果表明：随着糯小麦粉添加量的增加,配粉的糊化温度、峰值黏度、衰减度和回生值等快速黏度分析参数均呈现下降趋势,尤其是回生值降低显著。配粉的吸水量随糯小麦粉添加量的增加逐渐增大,面团的形成时间和稳定时间缩短,粉质指数降低;但当添加量增加至25.0%时,粉质特性各指标均产生显著性改变。不同配粉面团随着醒发时间的延长,面团拉伸曲线面积、拉伸阻力和拉伸比等指标均呈现一定的增大趋势,但延伸度却随醒发时间延长而降低。糯小麦粉配粉比例对馒头的质构和感官特性具有较大影响,适宜的糯小麦粉配粉比为20.0%～30.0%,25.0%配粉比使馒头具有较好的质构,感官总评分达到最大值。     

Partial Replacement of Wheat Flour with Yellow Field Pea Flour in White Pan Bread

Yellow field pea flour replaced 2.5, 5 and 10% of wheat flour in white pan bread prepared by a straight dough, rapid mix home formulation. Incorporation of pea flour did not affect proofing times. No significant differences were found between Gardner L and “a” values for wheat-pea flour blends, but “b” values increased with increasing levels of pea flour; crumb color of breads did not differ significantly. Volumes of the breads were not significantly affected by pea flour addition. Pea flour breads were judged between fair and good for all characteristics by an experienced taste panel; the 10% pea flour breads were scored significantly lower for texture, color and flavor.     

Effects of Defatted Jack Bean Flour and Jack Bean Protein Concentrate on Physicochemical and Sensory Properties of Bread

This study evaluated the effects of substituting wheat flour with defatted Jack bean flour and Jack bean protein concentrate on bread quality. Jack bean flour milled from the seed nibs was defatted with n-hexane and part of the defatted flour (DJF) extracted in acid medium (pH; 4.5) for protein concentrate (JPC). Both the DJF and JPC were analysed for nutrient composition, and then used to fortify bread. Five bread samples with 0%, 10% and 20% of DJF or JPC were prepared using straight dough procedure, and then analysed for quality characteristics. The DJF and JPC had 28.8% and 49.47% protein, 46.44% and 30.22% carbohydrate, 0.61% and 1.00% crude fibre respectively; and were rich in Ca, Fe, Zn and P. Both DJF and JPC improved quality of bread but JPC conferred better quality. The 20% DJF and JPC respectively improved protein content of bread from 9.45% to 10. 97% and 11.16%, crude fibre from 2.39% to 5.20% and 5.32%, fat from 2.35% to 7.00% and 6.55%, and ash content from 1.35% to 2.05% and 2.10% but decreased carbohydrate content from 72.12% to 50.45% and 50.39% in the bread samples. All the fortified bread samples had acceptable crumb colour, crumb texture, flavour and loaf volume significantly comparable (p > 0.05) to those of 100% wheat bread. Thus, defatted Jack bean flour and Jack bean protein concentrate is recommended for use in fortifying bread for higher quality.