Structural and some nutritional characteristics of Velvet bean (Mucuna pruriens) and Lima bean (Phaseolus lunatus) starches

Velvet bean (Mucuna pruriens) and lima bean (Phaseolus lunatus) starches were isolated from seeds and their structural characteristics evaluated using XRD, size‐exclusion chromatography and light scattering analyzes. Total starch, available starch, RS and in vitro digestibility were also determined. Structural and nutritional characteristics of Velvet bean and Lima bean starches were compared to those of commercial corn starch. The legumes starches presented a C‐type XRD pattern and crystallite sizes of 43.1 Å for velvet bean and 48.3 Å for lima bean. Lima bean starch average molar mass (4.9 × 10⁶ g/mol) was slightly higher than the velvet bean starch (3.04 × 10⁶ g/mol). Size‐exclusion chromatography indicated structural similarity between the lima bean and corn starches which differed from that of the velvet bean starch. Hydrodynamic radius (R_H) for the velvet bean and lima bean starches was 45.5 and 55 nm, respectively, and their radius of gyration (R_G) was 67.7 and 82.5 nm, respectively. Total starch content in all three starches was greater than 98%. Their complex crystalline structure provided the legume starches lower in vitro digestibility values than the corn starch. RS content in both the velvet bean starch (7.72%) and lima bean starch (5.66%) was higher than in the corn starch, essentially qualifying these polysaccharides as natural dietary fiber sources, with the associated physiologic advantages.     

Effects of common bean enrichment on nutritional quality of tortillas produced from nixtamalized regular and quality protein maize flours

In Mexico the tortilla is most commonly eaten in the form of ‘taco’; this is normally accompanied with other food, in particular the common bean. Tortillas made of quality protein maize (QPM) fortified with common bean might be a strategy to improve their protein quality. In this study, amino acids and mineral changes that occur during nixtamalization and the chemical and nutritional characteristics of regular, commercial and QPM tortilla–bean combination were assessed. After nixtamalization, protein from QPM nixtamalized maize flour was reduced from 8.1% to 7.2% (w/w). Tryptophan was also reduced from 12.1 to 11.1 g kg^?1 protein. QPM maize retained a higher amount (P < 0.05) of calcium (3180 mg kg^?1) compared to regular maize (1820 mg kg^?1). When nixtamalized maize flour of regular maize and commercial tortilla were combined with beans, protein content increased. The tryptophan and lysine contents in these tortillas were increased (P > 0.05) also, but were significantly lower (P > 0.05) than in tortilla made with QPM maize fortified with bean (22.7 and 69.9 g kg^?1 protein, respectively). Mineral contents increased in tortilla–bean combination. The QPM and tortilla fortified with bean gave an improvement in protein quality and could contribute significantly towards human nutrition, especially in countries like Mexico where maize and beans are important components of the diet. Copyright © 2007 Society of Chemical Industry     

挤压参数对绿豆粉糊化的影响

以绿豆为原料,采用双螺杆挤压膨化技术,对挤压膨化绿豆糊化进行了研究。结果表明,制备挤压膨化绿豆粉的最佳工艺条件为:喂料速度110r/min,加水量18%,膨化温度170℃,螺杆转速260r/min。影响挤压膨化绿豆粉糊化度主次顺序依次为:加水量、膨化温度、螺杆转速、喂料速度。在最佳工艺条件下,挤压膨化绿豆粉糊化度可达98.46%。      

1-甲基环丙烯处理对豇豆贮藏效果的影响

分别采用0.5、1.0、2.0μL·L-11-甲基环丙烯（1-methylcyclopropene,1-MCP）熏蒸处理豇豆,对其部分生理生化指标进行了测定,以探明1-MCP对采后豇豆的保鲜效果。研究结果表明,在（14.3±2）℃下,0.5μL·L-11-MCP处理组较CK组能显著地（p<0.05）延缓豇豆叶绿素、VC、可溶性蛋白含量的降低和纤维素含量的提高,并能减少丙二醛（MDA）的积累;贮藏结束时,2.0μL·L-11-MCP熏蒸较CK组能显著地（p<0.05）减缓多酚氧化酶（PPO）和过氧化物酶（POD）活性的升高,但会造成MDA的积累。在生产实践中,建议采用0.5μL·L-11-MCP熏蒸豇豆以获得好的贮藏效果。      

葛根黑豆挤压膨化工艺研究

以葛根粉和黑豆粉为主要原料,研究葛根粉与黑豆粉质量比、混合物料含水率、机筒Ⅲ区温度、螺杆主轴转速等因素对产品感官和糊化度的影响。通过单因素和正交试验优化葛根黑豆膨化食品的加工工艺,得到最佳工艺参数为机筒Ⅲ区温度150℃、螺杆主轴转速160 r/min、混合物料含水率17%、葛根粉与黑豆粉质量比1∶5,在该条件下生产出的产品具有较好的感官品质和糊化度。     

Fate of Fusarium mycotoxins in maize flour and grits during extrusion cooking

Extrusion technology is used widely in the manufacture of a range of breakfast cereals and snacks for human consumption and animal feeds. To minimise consumer exposure to mycotoxins, the levels of deoxynivalenol (DON) and zearalenone (ZON) in cereals/cereal products and fumonisins B₁ and B₂ (FB₁ and FB₂) in maize are controlled by European Union legislation. Relatively few studies, however, have examined the loss of Fusarium mycotoxins during processing. The behaviour of FB₁, FB₂ and fumonisin B₃ (FB₃), DON and ZON during extrusion of naturally contaminated maize flour and maize grits is examined using pilot-scale equipment. DON and ZON are relatively stable during extrusion cooking but the fumonisins are lost to varying degrees. There is some loss of ZON when present in low concentrations and extruded at higher moisture contents. The presence of additives, such as reducing sugars and sodium chloride, can also affect mycotoxin levels. Moisture content of the cereal feed during extrusion is important and has a greater effect than temperature, particularly on the loss of fumonisins at the lower moistures. The effects are complex and not easy to explain, although more energy input to the extruder is required for drier materials. However, on the basis of these studies, the relationship between the concentration of Fusarium toxins in the raw and finished product is toxin- and process-dependent.     

蛋清蛋白添加对籼米-绿豆粉粉质特性及挤压米粉丝品质特性的影响

将籼米粉、绿豆粉和蛋清蛋白粉按照一定的比例复配,开发高纤维含量的杂粮米粉丝。研究了绿豆和蛋清蛋白的添加对米粉糊化特性、流变特性以及挤压米粉丝微观结构、蒸煮特性和质构等品质特性的影响。结果显示:添加一定量的绿豆粉和蛋清蛋白粉后,混合粉的峰值黏度、最低黏度、最终黏度、回生值、弹性模量、黏性模量均逐渐下降。随着绿豆粉的添加(25%,50%),米粉的蒸煮时间、断条率、蒸煮损失和吸水率均上升,硬度降低,表明米粉的品质显著降低,由扫描电镜图可以发现,加了绿豆粉之后米粉截面变得越来越粗糙,裂纹和孔洞明显增多。但当加入7.5%的蛋清蛋白后,米粉的蒸煮时间、蒸煮损失和断条率均下降,质构特性有一定程度的改善,表明蛋清蛋白良好的凝胶特性有助于提升高纤维含量挤压米粉丝的品质。     

双螺杆挤压机操作参数对蚕豆挤出物径向膨化率的影响

以蚕豆粉为原料,以德国布拉本德DSE-25型双螺杆挤压实验室工作站为设备,研究挤压温度和物料含水率对挤出物径向膨化率的影响规律,进一步明确挤压温度、物料合水率与单位机械能耗和径向膨化率之间的关系.试验结果表明:挤压温度、物料含水率对单位机械能耗(SME)有极显著影响(α＜0.01);挤压温度、物料含水率和喂料速度对挤压物径向膨化率有极显著影响(α＜0.01),螺杆转速对挤压物径向膨化率有显著影响(α＜0.05).SME和径向膨化率两者之间呈显著正相关,相关系数为0.985 7(P ＜0.05).     

Physicochemical,nutritional and functional properties of marama bean flour

Marama bean is a protein-rich, underutilised, drought-tolerant legume in sub-Saharan Africa. Its utilisation may be increased through value addition into protein-rich flours. Defatted flour from unheated and dry-heated (150 °C/20 min) whole marama beans (UMF and HMF) were analysed for physicochemical and protein-based functional properties. Heating significantly increased in vitro protein digestibility of marama bean flour. Of functional importance are the high levels of tyrosine present in marama bean flours. Heating significantly reduced protein solubility and emulsifying capacity of marama bean flours whilst water absorption capacity was improved. Foaming capacity was not affected by heating. UMF could be useful in food systems requiring high emulsifying capacity, but would not be suitable for applications requiring high water absorption and foaming capacity. Due to its high protein contents, marama bean flour could be used to increase the protein quality of cereal-based foods to help alleviate protein-energy nutrition in the region.     

基于挤压蒸煮的荞麦粉加工品质改良及其机制研究

文章分析了挤压蒸煮对荞麦粉室温黏度和凝胶特性的影响,并利用体积排阻色谱测定了淀粉的分子量分布,探讨预糊化处理改善荞麦粉凝胶特性的机制;基于面带质地评价方法,优化预糊化荞麦粉在50%荞麦挂面中的添加比例。结果表明:荞麦粉经挤压蒸煮后,常温水中可形成凝胶;室温黏度显著增加;在主区温度200℃,水分含量18%,螺杆转速220r/min的条件下,所得预糊化荞麦粉中聚合度(DP)为6～50的支链淀粉分子最多,且此时凝胶强度最大。当预糊化荞麦粉添加量为10%时,面带抗拉能力最佳,黏附能力适中。由此可见,预糊化荞麦粉中特定链长的支链淀粉分子(DP 6～50)与凝胶品质呈正相关;50%荞麦挂面中添加适量预糊化粉可显著改善挂面的加工性能。     

不同加工方式对全豆蛋糕品质和营养价值的影响

采用烤箱烘烤和蒸锅蒸制2种不同加工方式分别制作全豆蛋糕,并对其感官性状和营养成分进行比较分析。结果显示:与蒸锅蒸制的全豆蛋糕相比,烤箱烘烤的全豆蛋糕感官评分更高;在营养成分方面,烘烤的蛋糕蛋白质、脂肪、碳水化合物、维生素A、维生素B2的含量以及能量均较高,但总膳食纤维和钙的含量却较低;亚麻籽油健康且稳定,可作为全豆蛋糕的烹调用油。2种加工方式各有优缺点,建议根据实际需求进行选择。     

挤压处理对麸皮、胚芽及全麦粉品质的影响研究

研究了全麦粉稳定化加工过程中挤压热处理对麸皮与胚芽的脂肪酸值、烷基间苯二酚、B族维生素、植酸、总酚、总抗氧化值等品质指标的影响。结果表明,挤压处理能有效地降低麸皮和胚芽的脂肪酸值,提高其抗氧化活性;有利于提高全麦粉的储藏稳定性;同时有利于保留麸皮与胚芽中的生理活性组分,很好的保持全麦粉的营养价值。因此,挤压加工是一种有效的全麦粉稳定化处理工艺。      

绿豆—小麦混合粉加工特性及其挂面品质研究

将绿豆粉和小麦粉按不同比例混合,研究绿豆粉对绿豆—小麦混合粉加工特性及其所制得挂面品质的影响。结果表明,随着绿豆粉添加量的增加,混合粉的湿面筋含量降低,稳定时间减少,面筋网络结构形成不足,耐搅拌能力下降,峰值粘度、最低粘度、衰减值、最终粘度、回生值、峰值时间不断减小,糊化温度不断提高,混合粉的加工品质趋于恶劣;挂面的烹调时间、烹调损失率上升,吸水率先升后降,添加量为30%时达到最大值,硬度、弹性、胶粘性、咀嚼性和回复性逐渐上升,断裂距离比先增后减,添加量为30%时达到最大值,在绿豆粉添加量超过50%以后,挂面无法制作。     

添加剂对黄豆粉速冻水饺品质的影响

将硬脂酞乳酸钙-钠(CSL-SSL)、海藻酸钠、瓜尔豆胶添加于黄豆粉速冻水饺皮中,测定其对水饺的冻裂率、破肚率和煮后水饺皮TPA特性.结果表明添加CSL-SSL对黄豆粉速冻水饺的冻裂率、破肚率及水饺皮TPA指标改善效果明显,最佳添加量为0.2%.     

挤压温度和物料水分对糙米粉中损伤淀粉及面条品质影响

在不同挤压温度和物料水分条件下将糙米粉挤压膨化,并将挤压膨化糙米粉与小麦粉的混合粉(1∶1,w/w)制成糙米面条,系统研究了挤压温度和物料水分对挤压糙米粉中损伤淀粉含量和糙米面条品质的影响,同时分析了损伤淀粉含量与面条品质的相关性。结果显示:随着物料水分的增加,糙米粉中损伤淀粉的含量显著减少,物料水分25%时损伤淀粉含量UCDc值达到最低14.9;随着挤压温度升高,糙米粉损伤淀粉含量先减少后增加,温度120℃时损伤淀粉含量UCDc值达到最低14.9;相关性分析结果显示,随着损伤淀粉含量的增加,面条蒸煮损失明显增大,坚实度、硬度和耐咀性降低,面条整体品质下降。挤压温度120℃、物料水分25%、损伤淀粉含量UCDc值为14.9,糙米面条品质相对较好。      

Incorporation of germinated mung bean flour with rice flour to enhance physical,nutritional and sensory quality of gluten-free cookies

Quality of the cookies substituted with germinated mung bean flour (GMF) to rice flour (RF) to produce gluten-free cookies were investigated in this study. The GMF was used to formulate with the RF to obtain the composite flours with different total protein contents of 6, 9, 12, 15, 18 and 21 (%, d.b). The increase in the substituted amounts of GMF contributed to the lower baking loss, diameter and spread ratio, but the higher thickness and hardness of the cookies as compared to the RF-based cookie. The cookies with more GMF substitution expressed lower lightness (L*) values, but higher redness (a*) and yellowness (b*) values than the others. The cookies substituted with 60% of the GMF (60-GMFC) exhibited similar baking loss, thickness, diameter, spread ratio and lightness values to the wheat flour (WF)-based cookies. The total amounts of essential amino acids and the sum of histidine, lysine and methionine of the composite flour-based cookies were 3.90% and 1.64%, significantly higher than those of the RF-based cookie (1.93% and 0.66%, respectively) or the WF-based cookie (1.70% and 0.58%, respectively). As a result, healthy gluten-free cookies could be prepared using the RF with the substitution of the germinated mung bean flour.     

挤压膨化对玉米粉发酵的影响

以玉米碴为原料,植物乳杆菌P8菌粉为发酵菌,考察了挤压膨化对玉米粉发酵的pH、总酸度、挥发酸的影响,并测定了玉米粉、膨化玉米粉的比表面积和孔径分布。结果表明,挤压膨化使玉米粉比表面积增加178%,孔径从2.89~17.93nm增大到3.42~20.47nm;与玉米粉相比,膨化玉米粉发酵至pH3.80时间约缩短12h、发酵至酸度13.5g/kg时间缩短6h;膨化增大了植物乳杆菌的作用面积,加快了发酵速度。      

Physicochemical and Functional Characterization of Baby Lima Bean (Phaseolus lunatus) Starch

One potential source of starch is the tropical legume baby lima bean (Phaseolus lunatus) that contains around 56—60% of starch. The objectives of this work were to evaluate this starch's physicochemical and functional properties and compare it with the properties of other starches. The chemical composition of lima bean starch was: 10.16% moisture, 0.20% protein, 0.67% fiber, 0.14% ash, 0.54% fat, 98.43% starch and 0.013% phosphorus. The amylose content was higher (32.7%) than that of other cereal and tuber starches but similar to other legume starches. The average granule size (diameter 17.9 μm) was comparable to that of corn starch and of other legume starches. The granule was heterogeneous, presenting an oval shape. The gelatinization temperature was 80.16 °C (range 75—87 °CC), which is similar to other legume starches but higher than that of corn starch. The molecular size (alkali number 3.22), was smaller than that of potato starch but similar to that of corn starch. Compared to corn starch, the gels were firmer and presented a higher degree of retrogradation even at high concentrations. The water solubility was positively correlated with the temperature: i.e., 1.8, 3.4, 8.5 and 12.3% at 60, 70, 80 and 90 °C, respectively. The swelling power had the same behaviour: 2.6, 3.3,12.8 and 19.9 g of water/per gram of starch at 60, 70, 80 and 90 °C, respectively. The amylogram showed that the viscosity (680 Brabender units) and stability were higher than those of commercial corn starch (252 Brabender units). The use of this starch in the preparation of syrups with high glucose contents, as well as in baked and canned products that require heating, is suggested.