Effects of the addition of wild legumes (Lathyrus annuus and Lathyrus clymenum) on the physical and nutritional properties of extruded products based on whole corn and brown rice

The effects of the addition of wild legumes (Lathyrus) from the South of Spain on the physical and nutritional properties of extruded products based on whole corn and brown rice were studied. Samples were obtained with a Brabender single screw extruder. The physical characterisation of the expanded products was performed by the measurement of density, expansion, solubility and specific mechanical energy consumption (SMEC). Chemical composition, amino acids content, protein digestibility, total polyphenol content and potential availability of iron and zinc were determined.     

Effects of the addition of hemp powder on the physicochemical properties and energy bar qualities of extruded rice

Extruded rice/hemp mixtures were prepared by mixing defatted and whole hemp powders with rice flour at varying hemp levels (0%, 20%, 30% and 40%). The influence of hemp powder type and level on physicochemical and antioxidant properties was studied. The bulk densities of the extruded rice/hemp samples increased with increase in levels of added hemp powder. The extrudates blended with hemp powder had a lower water absorption index than the control (extruded rice without hemp). The extruded rice/whole hemp had more total phenolics and flavonoids and had a better scavenging effect on DPPH radicals than extruded rice/defatted hemp. The highest potential to inhibit β-carotene oxidation was found in extruded rice/40% whole hemp. Increasing amounts of hemp powder resulted in lower equilibrium moisture content of energy bars. The energy bar made with extruded rice/20% whole hemp was preferred for colour, taste and overall acceptability.     

Effects of domestic preparation of cereals and legumes on ionisable iron

Effect of simple domestic processing on ionisable iron from cereals and legumes was investigated using an in vitro method. Two-fold increase was observed when legumes and cereal were germinated for different periods. In the case of legumes, increase was observed only with the whole grain, whereas no such changes were observed with decorticated legume. The ionisable iron from bread was higher (nearly twice) when compared with that from chapathi, prepared from the same wheat. The total iron was higher in the parboiled rice than in the raw rice. The percentage ionisable iron was lower in the parboiled rice than in the raw rice. The actual amount of ionisable iron, however, was the same in both the rice samples. Fermentation of rice and legume (pulse) mixture and cooking did not result in any change in the ionisable iron. Cooking of rice or wheat as used in Indian homes did not influence ionisable iron.     

Flavonol profile of cactus fruits (Opuntia ficus-indica) enriched cereal-based extrudates: Authenticity and impact of extrusion

In previous studies, it was hypothesized that isorhamnetin glycosides are the dominant flavonol derivatives occurring in the peels and cladodes of cactus Opuntia ficus-indica fruits and might be used as markers for analyzing the authenticity of food products containing (whole) cactus fruits or cladodes. In the present work, use of the whole yellow-orange fruit from cactus O. ficus-indica as an ingredient of rice- and corn-based snacks was evaluated. The impact of extrusion cooking on the flavonol profile was characterized in rice- and corn-based extruded products fortified with a freeze-dried preparation from the whole cactus fruit. HPLC analysis showed that the flavonol profile of cactus O. ficus-indica consisted of five prominent isorhamnetin glycosides with a concentration of 148.9 μg/100 mg dw. In contrast, the rice or corn grits used in the present study did not contain any flavonol at all. The freeze-dried fruit was added in different ratios (0, 2, 6, and 10%) to the rice or corn grits prior to the extrusion process. Analysis of the final extrusion products showed that flavonol profiles from the fortified rice or corn products, even at the lowest level of addition (2%), were similar to the original profile of the fruit before processing. Furthermore, the total flavonol content in extruded products was not significantly affected by extrusion cooking. This study showed that the unique flavonol profile of fruits from cactus O. ficus-indica might serve as a biochemical marker for the evaluation of the authenticity of products made from whole cactus fruit or the fruit's peel.     

Effect of iron compounds on the storage stability of multiple-fortified Ultra Rice®

Ultra Rice^® is an extruded, reformed rice grain used as a carrier for micronutrients. It holds great promise for alleviating micronutrient deficiencies in populations that consume rice‐based diets. We investigated the stability of multiple‐fortified Ultra Rice^® formulations in an effort to develop a stable premix containing iron, zinc, and B vitamins. The performance of four iron sources was tested under accelerated storage conditions (40 °C, 60% RH) over a period of 32 weeks. The effects of the iron source on micronutrient retention, oxidative stability, and sensory/physical properties were measured. Formulations containing ferric pyrophosphate (FePP) were the most stable, showing minimal losses of thiamin and good sensory/physical properties. Formulations containing ferrous fumarate lost more than 50% thiamin, while those containing iron‐sodium‐EDTA showed minimal loss of thiamin but developed the most rancidity. FeNaEDTA and ferrous fumarate resulted in darker coloured grains but they had a much higher in vitro bioavailability than the formulations containing FePP. The concentrations of zinc, folic acid, and niacinamide were not affected by the presence of iron during the storage tests.     

谷物蛋白肽对大米淀粉理化特性和体外消化特性的影响

本研究以大米淀粉为原料,探讨谷物蛋白肽的添加对大米淀粉理化性质和体外消化性能的影响。结果表明：添加10%的小麦肽对降低体系的峰值黏度、崩解值的效果最好,其值分别降低300 MPa·s;相反,5%的玉米肽使淀粉糊的终值黏度、回升值降低最大,分别降低256 MPa·s、200 MPa·s;谷物蛋白肽可以增大大米淀粉糊的焓变,提高淀粉糊的热稳定性;淀粉溶解度与谷物蛋白肽的添加量成正相关,3种肽对淀粉膨胀度无影响;大米肽能明显改变淀粉冻融稳定性,添加5%、10%可以使淀粉的冻融稳定性增强,析水率降低3%;3种肽可降低大米淀粉中易消化淀粉的含量,综合比较,大米肽对降低淀粉体外消化的效果最好,其中添加5%的玉米肽使易消化淀粉的含量降低值最大,降低25%,其次是添加1%的大米肽。根据谷物蛋白肽的主要氨基酸成分分析,大米肽的碱性氨基酸含量明显要比其他两种肽的含量高,玉米肽中的各氨基酸含量也相应的比小麦肽高;因而,谷物蛋白肽对淀粉的影响主要因素与各自的氨基酸含量以及分子量大小有关。     

Nutritional Quality of Drum-processed and Extruded Composite Supplementary Foods

ABSTRACT: This study was conducted to evaluate the nutritional quality of ready‐to‐eat composite foods intended for supplementary feeding of preschool age children in Tanzania. Four supplementary foods, namely, corn‐bean‐sardine meal (CBSM), bean meal (BM), sorghum‐bean‐sardine meal (SBSM), and rice‐bean‐sardine meal (RBSM) were formulated according to the FAO/WHO/UNU guidelines. The food mixtures were extruded, drum‐processed, and cooked conventionally in the traditional way. Cooking doneness was evaluated by percent starch gelatinization and residual urease activity; biological qualities—true protein digestibility and growth performance—were evaluated using Sprague Dawley weanling rats. Efficiency in destroying phytohemagglutinins and the antinutritional factors, trypsin, chymotrypsin, and α‐amylase inhibitors, were also evaluated. Results of the study showed that starch gelatinization and residual urease activity were not significantly different (P > 0.05) between the extruded and drum‐processed diets. Relative to conventional cooking, starch gelatinization was 95% to 100% in extruded and 90% to 100% in drum‐processed products. Inactivation of urease activity ranged from 93% to 100% in extruded and 83% to 100% in drum‐processed diets. The true protein digestibilities were significantly (P≥ 0.05) higher when extruded foods, compared with drum‐processed and conventionally cooked foods, were fed to experimental animals. Animals fed extruded products gained more weight relative to those fed drum‐processed and conventionally cooked foods. Destruction of phytohemagglutinins ranged between 91% to 97% in extruded and between 90% to 95% in the conventionally cooked and drum‐processed foods. Extrusion, drum processing, and conventional cooking also resulted in significant destruction of the antinutritional factors trypsin, chymotrypsin, and a‐amylase inhibitors. These results suggest that extrusion and drum processing of cereal‐bean‐sardine composite foods result in products meeting the required nutritional quality.     

Identification of Bioactive Peptides from Cereal Storage Proteins and Their Potential Role in Prevention of Chronic Diseases

Cereal grains, such as wheat, barley, rice, rye, oat, millet, sorghum, and corn, have been staples in human diets since ancient times. At present, there is a significant body of scientific evidence showing the health benefits of consuming whole grains in chronic disease prevention, particularly in regards to diabetes, cardiovascular disease, and cancer. The objective was to determine bioactive peptides in cereal grains that may prevent cardiovascular disease, cancer, inflammation, and diabetes. Bioactive peptides that may be obtained from cereal grains, particularly wheat, oat, barley, and rice, were identified. Bioactive peptides that play a role in chronic disease prevention have been found primarily in legumes and dairy products; although research connecting cereal grains with potential bioactive peptide activity is limited. In this review, 4 cereal grains, wheat, oat, barley, and rice, were evaluated for bioactive peptide potential using the BIOPEP database. In addition, research information was compiled for each grain regarding evidence about the effect of their proteins in prevention of chronic diseases. All 4 grains showed high occurrence frequencies of angiotensin‐converting enzyme‐inhibitor peptides (A = 0.239 to 0.511), as well as of dipeptidyl peptidase‐inhibitor and antithrombotic, antioxidant, hypotensive, and opioid activity. Wheat and rice proteins had anticancer sequences present. Wheat and barley showed the greatest diversity and abundance of potential biological activity among the cereal proteins. Further research needs to be conducted to learn how these biologically active peptide sequences are released from cereal grains. This study supports the notion that cereal grains are a nutritious part of a healthy diet by preventing chronic diseases.     

Effects of soaking whole cereal and legume seeds on iron,zinc and phytate contents

The effects of soaking whole cereal (maize, millet, rice, sorghum) and legume seeds (mung bean, cowpea, soybean) on iron (Fe), zinc (Zn) and phytate (Phy) contents were investigated. In all the above cereals, except millet, the molar ratios of Phy/Fe were above than 14, and ratios of Phy/Zn were above 20 while, in legumes, ratios were lower. Soaking whole seeds for 24 h led to leaching of iron and, to a lesser extent, of zinc ions into the soaking medium. Soaking led to a significant (P⩽0.05) reduction in the phytate content of millet, maize, rice and soybean, but did not improve the Phy/Fe molar ratio, while decreasing the Phy/Zn molar ratio only slightly. Soaking on its own was not found to be a good method for improving mineral bioavailability but the results showed that, in combination with other treatments, or with optimized soaking conditions, it could nevertheless prove useful.     

蛹虫草复合谷物杂粮膨化产品的工艺优化及糊化特性

目的：采用双螺杆挤压工艺制备蛹虫草复合谷物杂粮膨化产品,并研究蛹虫草对谷物杂粮膨化产品淀粉糊化特性的影响。方法：以大米粉、糯米粉、薏米粉、红豆粉、黄豆粉、蛹虫草粉为原料,按照一定比例混合制成蛹虫草复合谷物杂粮粉进行挤压膨化实验,并在单因素试验的基础上,选择物料水分含量、螺杆转速、进料速率、挤压温度为影响因素,产品径向膨化率、糊化度、水分含量、吸水性和水溶性指数为指标,设计正交试验,用极差分析法优化出蛹虫草复合谷物杂粮膨化产品的最佳工艺,并利用快速黏度仪测定谷物杂粮膨化产品和蛹虫草复合谷物杂粮膨化产品的淀粉糊化特性。结果：蛹虫草复合谷物杂粮膨化产品的最优工艺参数为物料水分含量16%、螺杆转速180 r/min、机筒的5 段挤压温度80-90-120-140-165 ℃、进料速率15 r/min,此时蛹虫草复合谷物杂粮膨化产品的径向膨化率、糊化度、水分含量、水溶性和吸水性指数分别为3.015、84.32%、6.11%、29.65%、416.39%;与谷物杂粮膨化产品相比,蛹虫草复合谷物杂粮膨化产品峰值黏度、保持黏度、最终黏度、回生值显著下降。结论：蛹虫草复合谷物杂粮膨化产品挤压工艺可行,添加蛹虫草能够显著降低谷物杂粮膨化产品的糊化特征值,并抑制其淀粉分子的回生或重排。     

Amaranth,millet and buckwheat flours affect the physical properties of extruded breakfast cereals and modulates their potential glycaemic impact

Three non‐traditional pseudo‐cereal flours (amaranth, buckwheat and millet) were used in the manufacture of extruded breakfast cereal products as a replacement for wheat and maize flour. The use of these flours altered the physical and nutritional quality of extruded breakfast cereals. Extruded products made using the flours exhibited an increased product and bulk density. However the extruded products were not significantly different compared to the control sample in terms of expansion ratio (excepting Amaranth at the 65% inclusion rate). All of the extruded products made with the inclusion of pseudo‐cereals showed a significant reduction in readily digestible carbohydrates and slowly digestible carbohydrates compared to the control product during predictive in vitro glycaemic profiling. The results illustrate the potential use of these non‐traditional cereal flours in lowering the glycaemic response to the ingestion of extruded breakfast cereals.     

Influence of Sulfonation on the Properties of Expanded Extrudates Containing 32% Whey Protein

Whey protein concentrate (WPC) was treated with sodium sulfite to achieve 4 levels of disulfide bond sulfonation (0%, 31%, 54%, and 71% mole/mole). The WPCs were blended with cornstarch to a 32% (weigh/weight) protein content and extruded into an expanded product. Extrudates were collected at 160 °C and 170 °C and analyzed for physical (air cell diameter, expansion ratio, breaking strength, and density) and chemical (water adsorption index [WAI], water solubility index, moisture content, soluble protein, and carbohydrates) properties. The control and 54% sulfonated samples had larger expansion ratios and air cell diameters and smaller densities and breaking strengths than the 31% and 71% samples. Expansion increased at 170 °C in the sulfonated samples. The WAI was influenced by both sulfonation and temperature, whereas the other chemical properties (except moisture content) were influenced only by sulfonation level. Soluble protein and carbohydrate were highest in the control and 54% samples. The anomalous behavior of the 54% sample may have been the result of significant structural and functional changes of α‐lactalbumin that are predicted to occur at approximately 50% sulfonation. Many functional properties of the WPCs were measured and were significantly correlated to the extrudate properties, particularly those related to protein unfolding and flexibility The increased ability for the proteins to become unfolded during extrusion may have promoted protein‐starch interactions, which led to decreases in expansion and overall quality Disulfide bond content did influence the chemical and physical properties of an extruded‐expanded whey protein products.     

Reduction of fumonisin B₁ in corn grits by twin-screw extrusion

Abstract: This study was designed to investigate the fate of fumonisins in flaking corn grits during twin‐screw extrusion by measuring fumonisin B₁ (FB₁) and its analogs with a mass balance approach. Food grade corn grits and 2 batches of grits contaminated with FB₁ at 10 and 50 μg/g by Fusarium verticillioides M‐2552 were processed with or without glucose supplementation (10%, w/w) with a twin‐screw extruder. Extrusion reduced FB₁ in contaminated grits by 64% to 72% without glucose and 89% to 94% with added glucose. In addition, extrusion alone resulted in 26% to 73% reduction in the levels of fumonisin B₂ and fumonisin B₃, while levels of both mycotoxins were reduced by >89% in extruded corn grits containing 10% glucose. Mass balance analysis showed that 38% to 46% of the FB₁ species detected in corn extruded with glucose was N‐(deoxy‐D‐fructos‐1‐yl)‐FB₁, while 23% to 37% of FB₁ species detected in extruded corn grits with and without added glucose was bound to the matrix. It was also found that the hydrolyzed form of FB₁ was a minor species in extruded corn grits with or without added glucose, representing <15% of the total FB₁ species present. Less than 46% of FB₁ originally present in corn grits could be detected in the fumonisin analogues measured in this study. Research is needed to identify the reaction products resulting from extrusion processing of fumonisin‐contaminated corn products. Practical Application: Twin‐screw extrusion is widely used in food industry for its versatility. This technology may reduce the level of fumonisins in corn particularly with added glucose.     

IMPROVED CORN AND MILLET BASED WEANING FOODS: FORMULATION, VISCOSITY, AND NUTRITIONAL AND MICROBIAL QUALITY

In Tanzania, germinated cereal flour is added to weaning foods consisting of ungerminated cereal or root crop flour and sometimes legumes to reduce bulk and viscosity, and increase nutrient density. However, there is no standard procedure for germinated cereal flour preparation and addition to gruels. This study was conducted to improve the chemical, physical and microbiological quality of millet and corn gruels based on protein and energy requirements for infants. Germinated millet flour (GMF) was more efficient than germinated corn flour in reducing gruel viscosity to < 3 Pascal s in 5 min. Washing before germination did not significantly reduce the microbial levels in GMF. Formulations consisting of millet, corn or combinations with soybean or peanut at a cereal: legume ratio of 7:3, and GMF were prepared by traditional and improved methods. In the lat-     

麦芽糖对糯性谷物淀粉糊化和流变性质的影响

以大黄米、糯米、糯玉米淀粉为原料,通过快速黏度分析仪、流变仪、差示扫描量热仪以及低场强核磁研究不同添加量的（2%、6%和10%）麦芽糖对糯性谷物淀粉糊化和流变性质的影响。结果表明：麦芽糖能够提高3 种糯性谷物淀粉的成糊温度,显著降低3 种淀粉的峰值黏度、终值黏度和回生值;随着麦芽糖添加量的增加,3 种淀粉糊的剪切应力逐渐降低,稠度系数降低,体系仍为假塑性流体,相比于大黄米淀粉和糯米淀粉,10%的麦芽糖对糯玉米淀粉的影响更大,稠度系数由32.546 Pa·sn降至4.801 Pa·sn,剪切变稀现象更为明显;热力学研究显示添加麦芽糖均能增加3 种糯性谷物淀粉的糊化温度和糊化焓值,且随着麦芽糖添加量的增加而升高;通过低场强核磁分析可知,添加麦芽糖使整个体系结合水与不易流动水含量增加,自由水含量减少,进一步解释添加麦芽糖能够降低体系黏度,增加淀粉糊化温度;本研究可为麦芽糖在糯性谷物食品中的应用提供指导。     

Protein digestibility‐corrected amino acid scores,acceptability and storage stability of ready‐to‐eat supplementary foods for pre‐school age children in Tanzania

This study was conducted to evaluate protein quality, acceptability and storage stability of processed cereal–bean–sardine composite foods for pre‐school age children in Tanzania. Four composite products namely corn–bean–sardine meal (CBSM), bean meal (BM), sorghum–bean–sardine meal (SBSM) and rice–bean–sardine meal (RBSM) were formulated to maximize the amino acid score for pre‐school age children and were processed by extrusion, drum‐processing and conventional cooking. The products were evaluated for true protein digestibility (TPD) and protein digestibility‐corrected amino acid score (PDCAAS). The TPD and PDCAAS were highest in the extruded products. The TPD values for the products ranged from 82 to 93%. The PDCAAS values for the composite foods were 64–86% and were greater than the minimum value of 60% recommended by FAO/WHO/UNU. There were no significant (p > 0.05) variations in the amino acid contents for foods processed by extrusion, drum‐processing or conventional cooking. Threonine was most limiting in the CBSM, SBSM and RBSM while methionine + cysteine were most limiting in the BM. Sensory evaluation showed that, relative to the traditional cornmeal—Uji, the extruded CBSM and SBSM had significantly superior (p ≤ 0.05) texture and highly acceptable color and taste. Storage of the products up to 16 weeks at 38 °C resulted in a small but significant increase (p ≤ 0.05) in the malondialdehyde concentrations; nevertheless, the levels remained within the acceptable range found in processed commercial supplements. Total acids, pH and organoleptic attributes did not change significantly (p > 0.05) during storage and the foods were acceptable to the end of the storage period. Copyright © 2005 Society of Chemical Industry     

Impact of Guar and Wheat Bran on the Physical and Nutritional Quality of Extruded Breakfast Cereals

Two non‐starch polysaccharides, guar gum and wheat bran, were used at 15% replacement level in a cereal base to produce an extruded breakfast cereal product from both wholemeal and high‐ratio wheat flour mixes. The inclusion of the non‐starch polysaccharides into the flour bases had no significant effect on the expansion ratio of the products. However, the product density and bulk density of the extruded products increased with guar gum and wheat bran addition. The pasting properties of the raw flour and polysaccharide base as well as the extruded products were altered with the incorporation of polysaccharides, with guar gum‐enriched products showing elevated peak and final viscosity readings. This appeared to be related to moisture manipulation and hence the regulation of gelatinisation. In vitro starch hydrolysis of the raw bases and the extruded samples illustrated that the extrusion process significantly increased the availability of carbohydrates for digestion. Additionally, the inclusion of non‐starch polysaccharides in the raw bases significantly reduced the rate and extent of carbohydrate hydrolysis. This potentially glycaemic reducing action was also evident in the extruded products where the incorporation of guar gum at 15% yielded a reduction of starch hydrolysis of 36% in the wholemeal base and 32% in the high‐ratio white wheat flour base.     

Biofortification of mungbean (Vigna radiata) as a whole food to enhance human health

Mungbean (Vigna radiata (L.) R. Wilczek var. radiata) is one of the most important pulse crops grown in South, East and Southeast Asia. It provides significant amounts of protein (240 g kg^?1) and carbohydrate (630 g kg^?1) and a range of micronutrients in diets. Mungbean protein and carbohydrate are easily digestible and create less flatulence than proteins derived from other legumes. In addition, mungbean is lower in phytic acid (72% of total phosphorus content) than pigeonpea (Cajanus cajan L. Millsp.), soybean (Glycine max L.) and cereals; phytic acid is commonly found in cereal and legume crops and has a negative impact on iron and zinc bioavailability in plant‐based diets. Owing to its palatable taste and nutritional quality, mungbean has been used as an iron‐rich whole food source for baby food. The wide genetic variability of mineral concentrations (e.g. 0.03–0.06 g Fe kg^?1, 0.02–0.04 g Zn kg^?1) in mungbean indicates possibilities to improve its micronutrient content through biofortification. Therefore biofortification of existing mungbean varieties has great potential for enhancing the nutritional quality of diets in South and Southeast Asia, where protein and micronutrient malnutrition are among the highest in the world. This review paper discusses the importance of mungbean in agricultural production and traditional diets and the potential of enhancing the nutritional quality of mungbean through breeding and other means, including agronomic practices. © 2013 Society of Chemical Industry     

Physical properties and chemical forces of extruded corn starch fortified with soy protein isolate

The effect of soy protein addition on physical properties of extruded corn starch was studied. The correlations between the chemical bonds in proteins and the physical properties of extrudates were analysed. Increasing soy protein isolate content resulted in higher expansion ratio (ER) but lower bulk density (BD), hardness, water solubility index (WSI), degree of starch gelatinisation (DSG), content of sulphydryl (SH) groups and protein solubility in phosphate buffer. In the other hand, increasing the processing temperature resulted in higher ER, water absorption index, DSG, contents of the SH group and disulphide (SS) bond but in lower specific mechanical energy, BD, hardness and WSI. The results indicated that changes in the chemical bonds in proteins had a significant effect on the apparent physical properties of extrudates. More protein–protein and protein–starch cross‐linking reactions occurred through new chemical linkages, such as the nondisulphide covalent bonds and hydrogen bonds, which are beneficial to the expansion of starch‐based products.