Diversification of Cassava Flour in the Manufacture of Gluten-Free Flakes Enriched with Dietary Fibers from Virgin Coconut Oil Waste Flour

Food diversification is a way to strengthen national food security, for example by reducing the dependence on wheat flour as a main raw material of various food products through the use of cassava flour. Cassava flour, a rich source of carbohydrates, can be used in the making of flakes. In this study, the Virgin coconut oil （VCO） waste flour was added in cassava flour to produce gluten-free cassava flour flakes with high dietary fiber contents. The six different formulas of flakes were used in this study with addition of 0% （control）, 10%, 20%, 30%, 40% and 50% coconut waste flour, respectively. Then, the chemical and microbiological characteristics of the flakes were measured. Based on the proximate data, both flours have a good quality. The microbiological analysis shows cassava flour and coconut waste flour have good sanitation and food safety. Results showed that flakes with 80% cassava flour and 20% coconut waste flour are gluten-free and contain 2.52% water, 2.27% ash, 14.40% fat, 4.50% protein, 76.31% carbohydrate, 8.56% dietary fiber. Therefore, it can be said that cassava flour flakes can serve as gluten-free and rich dietary fiber ready-to-eat food.

Physicochemical Characterisation of Flours from Local Cereals and Powder from Cassava (Manihot esculenta Crantz) Leaves Varieties Cultivated in the Northern-Cameroon in Order to Supplement Infant Flours

The aim of the present study was to investigate on the inventory and determination of the nutritional value of cereals flour and cassava leaves powder in order to analyse their use in the production of infant flour. In this paper, a A survey to identify the cereals used in the preparation of infant porridge in the Northern Cameroon was done by using 447 mothers having children between 06 and 59 months from areas (Gbakoungue, Sassa-Mbersi, Sanguere-Ngal and Kotkong-Wouldata) with high rate on malnourished children. Flour was prepared from the most preponderant cereals and Cassava leaves powder from varieties identified by the Regional Centre of Agricultural Research (CRRA) of Wakwa and local population. Flour and powder samples obtained were subjected to chemical composition analysis. Parameters analysed were crude proteins, total carbohydrates, ash, total fats, total phenols, total tannins, total carotenoids, vitamin C or cyanide. Also Iron, calcium and zinc were determined. The results revealed that white maize (62%) was the main cereal used in the preparation of infant porridge followed respectively by red sorghum, white rice and muskwari. Ten cassava varieties were identified: three (03) by CRRA (TME, 96/1/14 and IRAD 4115) and seven (south, gambada, sweet, Benin, six months, M. glaziovii and grouna) by local population. Amongst cereals flour, those from white maize indicated high protein (10.09%), carbohydrates (84.46%) and total fat (7.46%) contents. The powder from 96/14/14 cassava variety showed high amount of iron (11.98 mg/100g), calcium (751.02 g/100g) and low cyanide content (1.21 ppm) amongst all the cassava leaves powder samples. The supplementation of white maize flour by cassava leaves powder from 96/14/14 variety could therefore be recommended for the preparation of infant flours.

In-vitro digestibility,protein digestibility corrected amino acid,and sensory properties of banana-cassava gluten-free pasta with soy protein isolate and egg white protein addition

Soy protein isolate and egg white protein were added to cassava-banana gluten-free pasta and the effects on the nutritional quality,digestibility properties,protein digestibility corrected amino acid(PDCAA),and sensory acceptance of the pasta was observed.Banana-cassava composite flour(75:25)was blended with soy protein isolate or egg white protein at the following rates:0,5,10,and 15 g/100 g flour.Cooked pasta samples were analysed for total phenolic content(TPC),antioxidant activity,amino acid profiles,protein content,starch digestibility,protein digestibility and protein digestibility corrected amino acid score(PDCAAS).Addition of both proteins decreased starch digestibility,increased protein digestibility,improved the balance of the amino acid profile,and PDCAAS whereas only soy protein isolate enhanced the TPC and antioxidant capacity of the banana-cassava pasta.An egg white protein-fortified banana-cassava pasta had better customer acceptance and purchase intent than soy protein isolate inclusion.

Gluten-Free Flat Bread and Biscuits Production by Cassava, Extruded Soy Protein and Pumpkin Powder

In recent years, there has been an increase in demand of gluten free products that are suitable for people with celiac disease. The present study was carried out to produce gluten free flat bread and biscuits with good quality. The ingredients under this study were cassava flour, rice flour, extruded soy protein (ESP) and pumpkin powder. Four levels of ESP were used for production of flat bread and biscuits: 2.5%, 5%, 7.5% and 10% for flat bread and 5%, 10%, 15% and 20% levels for biscuits. Results of flat bread samples showed that protein, fat, ash and fiber contents increased in all samples as increasing the level of ESP. Flat bread at level 10% ESP had the highest value of β-carotene. Alkaline water retention capacity (AWRC) at zero time and 24 h of flat bread storage had high values for levels 2.5% and 5% ESP. Water holding capacity (WHC) increased insignificantly by increasing the level of ESP. Color measurements revealed that the lightness decreased and the redness increased with increasing the level of ESP. Sensory evaluation of flat bread revealed that 2.5% followed by 5% ESP level had high score of overall acceptability. Physical properties of biscuits indicated that as the level of ESP increased the diameter, thickness, volume and specific volume decreased. Biscuits sample with 20% ESP had the highest values of protein, fat, ash and fiber but the lowest in total carbohydrates. Also β-carotene and vitamin A content increased in biscuit samples. Caloric values of biscuits in all treated samples were lower than control. Lightness decreased while redness increased with increasing the level of ESP. Data of texture profile analysis (TPA) showed that hardness and adhesiveness (g) increased as ESP level increased. Sensory evaluation of biscuits showed that addition of ESP at 20% level decreased significantly texture score from 9.51 to 6.61 (P < 0.05) but insignificantly affected the other sensory scores.

White Gold: Cassava as an Industrial Base

A great number of production sectors in Africa that make use of maize, rice and wheat starches have carried out several experiments on cassava (Manihot esculenta) flour and starch, and found them to be potentially valuable substitutes. The benefits ranged from being a human staple food, constituent of animal feeds, and raw material in food processing, textile, pharmaceutical, detergent, alcohol and plastic industries to production of confectioneries like bread, spaghetti and chinchin. The vast availability of this “white gold” in most African countries can be explored in order to fully maximize its potential as an industrial base for interested entrepreneurs.

食用木薯粉脂肪酸组成分析及贮藏时间对其影响

木薯粉的脂肪酸组成和含量对其营养品质和贮藏期都有着重要的影响。实验以食用木薯粉为试材,通过优化脂肪酸甲酯化方法和气相色谱条件,建立了食用木薯粉中脂肪酸的定性定量检测方法,并对不同品种(系)、不同贮藏时间木薯粉中脂肪酸进行分析检测。结果表明:气相色谱法可准确对木薯粉中多种脂肪酸进行定性定量分析,棕榈酸、硬脂酸、油酸、亚油酸和亚麻酸浓度在20.0~1000.0、4.0~400.0、30.0~1500.0、10.0~500.0和2.0~100.0μg/mL的范围内线性关系良好,决定系数(R^(2))在0.9992~0.9999之间;样品重复性相对标准偏差(RSD)在0.5%~3.2%之间;样品在室温下放置24 h浓度变化的RSD在0.7%~1.1%之间;5种脂肪酸样品加标平均回收率在88.0%~105.4%之间,平均回收率RSD在3.4%~10.4%之间,证明样品稳定性、方法重复性和准确度较好。不同食用木薯品种制备的木薯粉中主要有棕榈酸、硬脂酸、油酸、亚油酸、亚麻酸5种脂肪酸,其品种间脂肪酸含量差异较大,5种木薯粉脂肪酸比例(SFA/MUFA/PUFA)为1:(0.91~1.35):(0.12~0.39)。其中,‘华南9号’食用木薯粉中棕榈酸、油酸、亚油酸和亚麻酸含量显著高于其他品种(系)(P<0.05),含量分别达到了0.7818、1.088、0.2967和0.0398 mg/g;而该品种的硬脂酸含量最低,仅为0.0868 mg/g。常温贮藏实验表明,5种脂肪酸含量与贮藏时间呈负相关,其中油酸、亚油酸和亚麻酸呈极显著负相关(P<0.01);5种脂肪酸含量在贮藏12周时达到最低,贮藏后期变化趋于平缓。研究结果可为评价不同品种(系)食用木薯粉中脂肪酸的组成和贮藏过程中脂肪酸的变化提供检测依据。

不同菌种发酵木薯粉品质和糊化特性比较分析

以华南9号木薯(SC9)块根为原料,利用5个菌种进行发酵,比较分析发酵前后木薯粉常规营养品质、有机酸风味物质组成和结构特性等差异。结果表明,酿酒酵母(Saccharomyces cerevisiae)发酵显著提高(P<0.05)木薯粉的蛋白质含量,比对照组提高2.2倍,达0.83 g/100 g;而许旺酵母(Schwanniomyces occidentalis Klocker)发酵可显著降低氰化物含量(P<0.05),降解率达91.82%;枯草芽孢杆菌(Bacillus subtilis)发酵后有机酸含量最高,达到10.987 mg/g,并显著提高了粗多糖得率(P<0.05),达到1.59%。从加工特性看,枯草芽孢杆菌发酵后,糊化特性的峰值黏度、谷值黏度、最终黏度均显著提高(P<0.05)分别为5397.5、3439.0、4770.0 mPa·s,衰减值显著降低(P<0.05),为1958.5 mPa·s。结构特性分析表明,发酵后木薯粉淀粉颗粒均匀,显著变小。综合对比,利用枯草芽孢杆菌发酵木薯粉,有利于提高木薯粉的脂肪、有机酸、粗多糖等营养品质并较好改善其加工特性。

木薯全粉对蛋糕品质及其质构特性的影响

以不同比例木薯全粉替代低筋面粉制作蛋糕,研究木薯全粉对蛋糕物理特性、感官品质和质构特性的影响,对其品质和质构指标进行评价。结果表明:随着木薯全粉替代比例的增加,蛋糕回缩率先降后升,感官总分先升后降,烘焙损失率、密度、硬度和咀嚼性不断升高,比容、水分含量、弹性和内聚性不断降低;替代比例为10/90~30/70的蛋糕回缩率、烘焙损失率、密度均比对照低,水分含量比对照高,有利于蛋糕品质的提升;替代比例为30/70的蛋糕比容、感官总分、硬度、咀嚼性和内聚性与对照差异不显著;替代比例超过40/60后,与对照组相比,蛋糕回缩率、烘焙损失率、硬度和咀嚼性显著升高(P<0.05),比容、感官总分、水分含量、弹性和内聚性显著降低(P<0.05),蛋糕品质下降。

热处理对木薯全粉品质的影响

为充分发挥木薯资源的应用优势,增加木薯的消费途径和产品价值,该文将研究制备具有良好口感、方便食用的木薯全粉。通过筛选热处理的温度、时间,以及预煮和蒸煮工序的组合方式,同时利用响应曲面法研究确定木薯全粉的制备工艺参数,提高热处理过程中木薯细胞的分离效率。结果表明影响木薯全粉细胞完整性的热处理因素依次为蒸煮温度、蒸煮时间、预煮温度、预煮时间,其最佳值分别为95℃、16min、10min、66℃。在此条件下生产的木薯全粉游离淀粉质量分数较低,为8.4%,制备的木薯全粉具有理想的细胞完整度。同时,研究分析了木薯加工过程中氢氰酸的变化,以及木薯全粉的黏度性质、热力学特性、吸水、吸油和冻融稳定性,从而为木薯全粉在食品工业上的应用提供理论参考。

木薯全粉对饼干储藏期品质和质构特性的影响

研究了木薯全粉对饼干储藏期品质和质构特性的影响,以不同比例木薯全粉替代低筋面粉制作饼干,对其理化和质构指标进行评价。结果表明:添加木薯全粉使得饼干的明亮度下降,色泽变黄。木薯全粉可降低储藏期饼干的水分含量和吸水率,提高脆性。其中,木薯全粉与低筋面粉比例为30/70时,饼干在储藏期内水分含量、咀嚼性和硬度最低,脆性最高。当木薯全粉与低筋面粉的比例大于40/60时,与对照组相比,饼干的硬度、弹性和咀嚼性升高,饼干的品质下降。

木薯全粉面条配方的优化

以华南9号木薯全粉替代小麦面粉为原料,辅以谷朊粉、黄原胶、乙酰化二淀粉磷酸酯等改良剂制备木薯全粉面条,通过单因素和正交实验优化木薯全粉面条配方,考察指标包括感官评价、断条率及蒸煮损失率。确定木薯全粉面条的最佳配方为:谷朊粉用量6%(g/100 g木薯全粉),黄原胶用量1.5%,乙酰化二淀粉磷酸酯用量9%,食盐用量1%,热水(95±2)℃用量为56%(g/100 g总原料粉)。用最佳配方制作面条,氢氰酸未检出,食用安全;熟断条率为0%,蒸煮损失率为7.8%,均符合挂面行业标准(LS/T 3212-2014)指标要求,表明使用木薯全粉制作面条技术是可行的。

木薯全粉的功能特性

开发推广木薯源大宗食物,充分发挥木薯的资源优势,拓展人们日常消费的食物资源,积极应对日益严重的粮食危机。通过对木薯全粉与鲜木薯、木薯淀粉中的营养成分的测定对比,及对木薯全粉的黏度特性、透光率、膨胀度等进行分析,并对木薯全粉的营养成分保留及功能性质进行评价,探讨木薯全粉在食品工业中的潜在应用范围。结果表明,木薯全粉相对于鲜木薯、木薯淀粉营养成分保持良好,食用安全,同时具有较好的加工性能,在食品工业中应用前景广阔。

食用木薯全粉添加量对饼干品质、质构特性及消化性能的影响

以食用木薯全粉、低筋面粉、黄油、白糖粉等为原料,利用烘焙法制备饼干,研究食用木薯全粉添加量对饼干品质、质构特性及消化性能的影响。结果表明,添加量为30 g的饼干感官品质、质构特性和消化性能均处于最优水平。添加量为10、20、30、40、50 g的饼干吸水率、L~*值、快速消化淀粉(RDS)含量分别比对照低3.76%、6.21%、7.78%、12.02%、15.72%(p<0.05),0.16%、0.94%、1.94%、4.06%、6.74%,2.30%、4.30%、7.17%、9.30%、14.07%(p<0.05);a~*值、b~*值、慢速消化淀粉(SDS)含量分别比对照高35.92%、62.62%、71.60%、107.04%、117.48%(p<0.05),5.39%、6.03%、7.14%、7.18%、9.34%(p<0.05),12.89%、26.17%、50.47%、81.07%、120.27%(p<0.05)。因此表明,食用木薯全粉用于饼干产品开发能提升产品品质,且具有一定的保健功能。

一株运动发酵单胞菌Zy-1快速生产乙醇

经多次实验优化，得到运动发酵单胞菌Zy发酵葡萄糖生产乙醇较合适的条件．Zy的诱变菌株Zy-1在该条件下发酵葡萄糖生产乙醇比原始菌株更有较大优势．当葡萄糖浓度为200gL^-1时，发酵48h，乙醇浓度96．5gL^-1，残糖2．3gL^-1，发酵效率为94．42％．Zy-1发酵天然原料米粉、木薯、红薯干等，发酵时间44h，乙醇浓度达95gL^-1以上，发酵效率92％以上．发酵液用DNS法测定，还原糖约2gL^-1，残总糖因原料种类不同，其值有所差异（5～20gL^-1）．经薄层层析分析，发酵液无葡萄糖，而是二糖、三糖等低聚糖．

木薯淀粉制燃料酒精的技术研究

利用α耐高温淀粉酶、糖化酶及酵母菌Saccharomyces cerevisiae Q2-1对木薯淀粉发酵酒精的液化、糖化及发酵等几个阶段进行研究。结果表明,pH值与时间因素对木薯淀粉液化结果的影响达显著水平(P<0.05),料水比因素对试验结果影响不显著(P>0.05);糖化时间对木薯淀粉产还原糖量影响达显著水平(P<0.05);发酵过程中以添加0.5%硫酸铵的效果最好,发酵3d的酒精度为10.81%(v/v),为不添加氮源的4.98倍,淀粉出酒率达51.88%。

用糖蜜水解液对木薯粉调浆进行浓醪酒精发酵工艺研究

[目的]研究用糖蜜水解液对木薯粉调浆进行浓醪酒精发酵的工艺条件。[方法]利用硫酸对糖蜜进行水解,再用糖蜜水解液对木薯粉调浆进行浓醪酒精发酵。考察糖蜜水解pH值、水解温度及保温时间对糖蜜水解程度的影响。[结果]在糖蜜锤度30°Bx,pH值2.4,水解温度125℃,保温时间40 min时糖蜜中蔗糖转化率可达95.0%。[结论]利用糖蜜水解液(占总糖比例20%)对木薯粉调浆进行浓醪酒精发酵,发酵醪在发酵过程的流动性显著增加,发酵成熟醪酒精浓度为15.5%,达到浓醪发酵水平。

黄浆水与木薯粉混合发酵高浓度乙醇的发酵条件

以黄浆水与木薯粉混合同步糖化发酵高浓度乙醇,应用Plackett-Burman设计对底物浓度、尿素、糖化酶、液化酶、MgSO4、pH值、CaCl2、KH2PO48个因素进行2水平12次试验,研究发酵的最佳条件。结果发现,底物浓度、尿素、糖化酶和KH2PO4的添加量是影响发酵的重要因素,最佳发酵条件是底物浓度38%、尿素0.15%、糖化酶1.45AGU/g、KH2PO40.07%。在最佳发酵条件下,乙醇浓度达到17.21%(V/V)。

细度对食用木薯粉理化品质和消化特性的影响

以食用木薯粉为主要研究对象,研究不同细度食用木薯粉理化品质、加工特性、消化和热分解特性。结果表明:不同细度食用木薯粉的淀粉含量和粗蛋白含量达显著差异,其中80目的蛋白质含量最高;而溶胀度、可溶性分别与细度呈负相关和正相关关系;从热分解特性看,不同细度食用木薯粉DSC曲线具有两个峰值温度,而80目食用木薯粉焓变最大,达到-882.88 kJ/kg,热稳定性差。进一步研究其消化特性发现,食用木薯粉细度越大,其快速消化淀粉(RDS)含量越高,但慢消化淀粉(SDS)含量则相反。相关分析表明,粗蛋白含量分别与RDS、SDS呈极显著负相关(-0.74071)和正相关(0.86628)。细度不仅显著影响木薯粉的稳定性,还决定木薯粉的消化性能。

食用木薯块根及其制品中生氰糖苷检测方法的建立与应用

生氰糖苷含量的高低对评估食用木薯块根及其制品的食用安全性及其重要。以木薯块根和木薯粉为试材,本研究建立了亚麻苦苷和百脉根苷2种生氰糖苷(Cyanogenic Glycosides,CNGs)的快速提取和高效液相色谱-蒸发光散射(HPLC-ELSD)检测的方法,分析了不同品种木薯块根、木薯粉及其制品中CNGs含量变化。结果表明,食用木薯块根及木薯粉中CNGs提取最佳的硫酸溶液浓度分别为0.025和0.100 mol/L;HPLC-ELSD检测方法可有效分离亚麻苦苷和百脉根苷,其浓度在4.1~820.0 mg/L和2.5~250.0 mg/L范围内线性相关性较好,相关系数(r)分别达到了0.9996和0.9993,检测限(LOD)分别为2.1和0.5 mg/kg,定量限(LOQ)分别为8.2和2.0 mg/kg;该方法重复性和样品稳定性的标准偏差(RSD)都低于5.0%;木薯块根和木薯粉中2种CNGs的平均加标回收率分别在89.3%~96.3%和107.5%~114.9%之间,重复间RSD小于3.4%。样品验证结果表明:不同的木薯品种CNGs含量差异较大;种植8~9个月的木薯制备木薯粉CNGs含量较低;蒸煮加工方式可有效清除木薯食品中CNGs。本方法操作简单、稳定性较好、准确度高,在食用木薯块根及其制品中CNGs的分析与评价等研究方面具有较强的应用前景。

木薯粉及制品中高灵敏度AFB;快速检测方法研究

【目的】基于酶联免疫吸附测定法(ELISA)检测原理,建立高灵敏度的直接竞争法检测木薯粉及其制品中的黄曲霉毒素B_(1)(AFB_(1)),为木薯食品安全提供技术支持。【方法】通过对AFB1抗原结构改造、免疫和细胞融合等过程获得抗原抗体,建立高灵敏度检测方法,并进行木薯粉及其制品样本的实例验证。【结果】制备的AFB1抗原和抗体,其抗体亚型均为IgG_(1),灵敏度最高的3F2细胞株产生的抗体对黄曲霉毒素G_(1)、G_(2)和B2交叉反应率分别为21.4%、1.9%和8.8%,且对其他毒素类无交叉反应,建立的ELISA线性区间为0.02~0.48μg/kg,半数抑制浓度(IC_(50))为0.047μg/kg,标准方程为y=-3.074x-4.3066(R2=0.9978)。以35%甲醇水溶液作为标准品稀释液,木薯食品原料用70%甲醇水溶液加0.2 g NaCl作为提取液,含油脂的木薯糕点用70%甲醇水溶液作为提取液,所有样本均为10倍稀释,检测限0.2~4.8μg/kg,样品添加回收率81.5%~120.0%,变异系数均小于8.5%。应用验证试验表明,自建ELISA试剂盒对96份样本检出19份阳性样本,购买试剂盒检出7份阳性,大于2.0μg/kg的样本检测结果完全符合,自建ELISA试剂盒方法灵敏度优于购买的ELISA试剂盒。【结论】本研究建立的直接竞争ELISA方法灵敏度高,操作简单,可广泛应用于木薯粉及其制品样本中AFB1的快速测定。