Functional properties of the starchy flour extracted from cassava on fermentation with a mixed culture inoculum

The functional properties of the starchy flour extracted from six varieties of cassava subjected to fermentation by a mixed culture inoculum comprised of lactobacilli, streptococci, corynebacteria and yeast cells are examined. Apparent reduction in total and soluble amylose contents is observed. Differential scanning calorimetry of the samples indicated that the enthalpy of gelatinisation was reduced, while the gelatinisation temperature was enhanced. A marked reduction in Brabender viscosity values of starch from fermented tuber was observed, but the X-ray diffraction pattern was unaffected. All these changes were attributed to the presence of fibrous material and consequent reduction of starch in unit volume rather than any change in the starch granule structure.     

从甘薯渣发酵醪液中制备的膳食纤维的物化特性研究

以甘薯渣酒精发酵后的醪液为原料,采用物理筛分法制备膳食纤维。测定酒精发酵醪液制备的膳食纤维(AFDF)的化学组成成分、显微结构、色泽、粒度、吸水膨胀性、持水性和持油性,并分别与甘薯膳食纤维(SPDF)、大豆膳食纤维(SDF)和燕麦膳食纤维(ODF)进行比较。结果表明:AFDF纯度最高,为82.46%,其显微结构为多孔状,粒径在1～60μm范围内,具有较好的吸水膨胀性(13.26mL/g)、持水性(11.84g/g)和持油性(1.85g/g),因而是一种潜在可利用的膳食纤维资源。     

红薯浆的酶解与发酵制备红薯全汁酸奶的研究

以红薯浆为原料,通过添加纤维素酶,α-淀粉酶对其进行水解得到红薯浆全汁。结合单因素和正交实验,确定了最佳酶解工艺,即纤维素酶添加量0.7%、酶解时间3.0h、加水量与薯液比5:1,pH6.5,在此酶解工艺条件下,出汁率可达42%。以红薯乳全汁为原料,接种乳酸菌对其进行发酵制备红薯乳全汁酸奶;以产品酸度、黏度和持水力等理化指标并结合感官评价指标为考察依据,通过正交实验确定了最佳发酵工艺为:红薯浆与脱脂乳比例5:5,菌种接种量5%、发酵温度37℃、蔗糖添加量4%。在此条件下所得红薯全汁酸奶理化和感官指标均为最佳。      

甘薯淀粉的理化特性、生产与应用

甘著是世界第六大粮食作物,淀粉含量高达其块根干重的80％,广泛应用于食品、医药和化工等行业.介绍了甘薯淀粉的理化特性、生产技术以及应用现状,以期为甘薯淀粉的进一步研究和有效利用提供参考.     

紫薯-小麦混合粉的性质及在面条上的应用

紫薯全粉保留了鲜薯的色泽和营养,是极好的食品加工原料,能够弥补小麦粉营养结构单一的缺点。将紫薯粉添加到小麦粉中,对混合粉的特性及在面条上的应用进行了研究,结果表明：随着紫薯粉的添加量由0%增加到30%,混合粉的糊化温度由66.31℃上升至67.73℃;糊化黏度、崩解值和回生值均减小;面团稳定时间由18min下降至7.8min;紫薯面条煮沸损失率由7.2%上升至11.8%;最大拉伸应力、剪切应力及硬度均减小;面条色度变暗,色泽向紫红色渐变。紫薯粉最佳添加量为15%。     

甘薯全粉生产过程中护色工艺研究

主要研究甘薯全粉生产工艺环节中护色剂、护色时间、及高温处理对甘薯护色效果,利用回归正交得到最佳复合护色剂,即0.58%柠檬酸和0.5%亚硫酸钠。通过单因素试验,得出复合护色剂最佳浸泡时间为45min;经护色处理后甘薯多酚氧化酶(PPO)活性为0.083,其抑制率达87.52%。     

甘薯淀粉性质的研究

研究了甘薯淀粉的理化性质,结果表明:其颗粒粒径的平均值为5~31mm,结晶结构属C型,直链淀粉含量18.5%,糊化温度为60.8~78.5℃。甘薯淀粉的透明度为42%,凝胶强度为98g。     

Altering pasting characteristics of sweet potato starches through amino acid additives

ABSTRACT:  This study assessed the effects of amino acid additives, aspartic acid, leucine, lysine, and methionine, on the pasting and thermal characteristics of white- and orange-fleshed Beauregard sweet potato starches. A rapid visco analyzer 3D was used to determine pasting properties. In comparing pasting characteristics, starch from orange-fleshed sweet potato was found to be easier to cook, had a lower potential for retrogradation, and was less stable during heating than the white-fleshed sweet potato starch. The RVA analysis showed that the charged amino acids, aspartic acid and lysine, altered pasting characteristics of the 2 starches more than the neutral amino acids, leucine and methionine. Aspartic acid had similar effects on both starches, making them less stable during cooking and lowering the potential for retrogradation. Lysine, when added to the orange-fleshed sweet potato starch, decreased the breakdown, allowing for more stability during cooking. This study showed that pasting properties of sweet potato starches can be altered by the addition of amino acids.     

红薯酸牛奶发酵技术研究

以红薯浆、鲜牛乳为原料,发酵制得营养丰富、口味独特的红薯酸牛奶。对红薯酸牛奶的配料组合、生产工艺和发酵条件进行了探讨。     

红薯乳酸菌发酵酸奶的研制

以红薯液、牛乳为原料,发酵制得营养丰富、口味独特的红薯酸牛奶;将保加利亚乳杆菌和嗜热链球菌按1∶1的比例3%的接种量接入原料中,结果表明:红薯液与牛乳以5:5混合、发酵温度39℃、发酵时间12 h比较适宜.     

乳酸菌发酵南瓜红薯复合酱的研制

以南瓜、红薯为原料,通过正交试验最终确定乳酸菌发酵南瓜红薯最佳发酵条件:发酵剂接种量为原料质量的3%,加盐量为原料质量的0.6%,发酵温度24℃,时间16d;乳酸菌发酵南瓜红薯复合酱原料配比为南瓜:红薯1:2,砂糖加入量为原料质量40%,灭菌温度100℃,时间20min。产品呈浅黄色,口感细腻、酸甜适口、有一定流动性,无分层,无析水现象,既有南瓜红薯天然清香,又有乳酸菌发酵特有的风味,无异味。     

Physicochemical properties of sweet potato starch

Tropical root crops, of which the sweet potato is an important representative, constitute an under exploited resource of developing countries. They can be used as food for both human and animal consumption and their starch is a source of industrial raw material. This review will consider recent reports on sweet potatoes, the physicochemical properties of their starches in comparison with other starches, and the possible causes of variation in these characteristics.     

红薯膳食纤维饮品的生产

红薯渣为红薯淀粉加工过程中的副产物。利用食用菌生物降解与转化红薯渣形成发酵液,以此发酵液为主要原料,经过均质、调配等工艺,制成浅黄白色、黏度适中、状态均匀的膳食纤维饮品,可以作为日常膳食纤维的补充。     

紫薯酸奶发酵工艺研究

以紫薯和脱脂乳粉为主要原料,制得一种新型的发酵紫薯酸奶。选用嗜热链球菌和保加利亚乳杆菌,以3:2的比例组成混合发酵剂进行乳酸发酵,以感官评价等为考察指标,通过正交试验确定紫薯酸奶发酵工艺条件。结果表明,紫薯酸奶发酵最佳工艺参数为:白砂糖添加量7%、发酵温度41℃、发酵时间6h、紫薯添加量6%。在此条件下发酵,得到色泽均匀、组织状态良好、口感细腻、具有保健功能的凝固型紫薯酸奶。     

甘薯活性乳酸菌饮料的研制

以甘薯浆和鲜牛奶为主要原料进行乳酸发酵，研制出一种组织均匀、口感细腻，即有营养又有保健功能的天然饮料，并通过正交试验确定了最佳工艺参数。     

Effect of high hydrostatic pressure to sweet potato flour on dough properties and characteristics of sweet potato‐wheat bread

The effect of high hydrostatic pressure (HHP, 100–400 MPa) for 20 min at 25 °C to sweet potato flour (SPF) on dough properties and characteristics of sweet potato‐wheat bread was investigated. The particle size of SPF after HHP was decreased significantly. The obvious rupture was observed in granules of SPF after HHP at 300 and 400 MPa by scanning electron microscopy (SEM). After HHP, significant differences on endothermic peak temperatures (T_P) of SPF were observed by differential scanning calorimetric (DSC), of which the enthalpy change (ΔH) had a slight increase, expect that at 200 MPa. Gas retention of dough with SPF after HHP increased markedly from 1199 (0.1 MPa) to 1246 ml (100 MPa). Specific loaf volume of bread with SPF at 400 MPa was increased significantly, while the hardness and chewiness were reduced. Thus, SPF treated with HHP at 400 MPa could be potentially used in wheat bread production.     

不同干燥方式对紫薯全粉品质的影响

紫甘薯具有很高的营养价值,紫薯全粉的开发研究有利于其加工的扩大化和优质化。以紫薯为原料,通过鼓风干燥、真空冷冻干燥、真空干燥三种干燥方法对紫薯全粉的制备进行研究,探讨三种方式对于紫薯全粉基本化学成分、色差、碘蓝值、持水性和持油性、总花青素含量等品质的影响。通过对比实验得出结论,真空冷冻干燥对于紫薯全粉的基本化学成分、色差、碘蓝值、持水性和持油性、总花青素含量等品质的综合影响最小,真空干燥紧随其后。因此,为了保持紫薯全粉的完整性,同时考虑生产成本,在加工紫薯全粉过程中以真空干燥方法为最佳。     

Characterisation of flour, starch and fibre obtained from sweet potato (kumara) tubers, and their utilisation in biscuit production

Sweet potato (kumara) tubers of differing colours (orange, red and white) were used to produce tuber flour, a purified starch fraction and an isolated fibre extract. The fractions from each tuber colour were added into a biscuit mixture, and the effects of tuber source and fraction composition were observed in relation to the physico-chemical characteristics of biscuits. Addition of sweet potato flour and fibre fractions to white wheat flour significantly reduced the pasting properties (peak and final viscosity) of the resulting gels by up to seven-fold compared with the control wheat flour gel (as determined by the Rapid Visco Analyser). The addition of sweet potato starch affected the pasting properties of wheat flour–sweet potato starch mixes to a lesser extent. Biscuit texture (force required to cause a biscuit to fracture) was significantly reduced with the incorporation of sweet potato fibre into the biscuit dough preparation, this was linked to a reduction in biscuit thickness and spread ratio. However, the addition of sweet potato flour and starch resulted in biscuits of similar firmness as the control biscuits.     

精制甘薯淀粉的生产技术

采用去皮工艺,控制沉降的温度和pH值,在破碎的同时加入0.005％抗坏血酸和0.005％亚酸酸钠,生产出精制甘薯淀粉,其白度达到88.80。     

食用交联甘薯淀粉制备与性质研究

以甘薯淀粉为原料,三偏磷酸钠为交联剂,对甘薯淀粉进行变性,制备食品用交联甘薯淀粉。以交联淀粉峰值粘度和结合磷含量为指标,以三偏磷酸钠用量、反应pH、温度、时间和硫酸钠用量为因素研究交联反应最优工艺;并研究系列食用交联甘薯淀粉粘度、溶解度、膨胀度、透明度、凝沉性、冻融稳定性等理化性质及形态学和结构性质,为其在食品中应用提供理论依据。