Proximate composition,provitamin A retention,and shelf life of extruded orange‐fleshed sweet potato and bambara groundnut‐based snacks

Evaluating the effect of processing on nutrient content and shelf life is important when developing new products. Six formulations of orange‐fleshed sweet potato (OFSP) and bambara groundnut were extruded at a feed rate of 10.15 kg/hr, screw speed of 30 rpm and at 100 and 130 °C in first and second zones respectively. Proximate composition was determined using standard methods. Provitamin A was determined using high‐performance liquid chromatography. An untrained panel (n = 73) was used to determine consumer acceptability. Shelf life was predicted by using peroxide values. Concentration of OFSP or bambara groundnut significantly (p < .05) affected proximate composition of the snacks. Moisture (4.79–8.34 g/100 g), carbohydrates (55.53–78.99 g/100 g) and provitamin (0.54–17.33 mg/100 g) contents increased with increase in proportion of OFSP. Protein (4.08–15.03 g/100 g), fat (4.20–12.74 g/100 g), fiber (5.29–6.46 g/100 g), ash (0.09–4.80 g/100 g), and energy (366.13–396.9 kcal/100 g) increased with increasing proportion of bambara groundnut in the formulation. Extrusion significantly (p < .05) reduced provitamin A content from 0.90–20.73 to 0.54–17.33 mg/100 g. Presence of OFSP improved provitamin A retention and consumer acceptability. Predicted shelf life (ranged from 118 to 150 days at room temperature) was inversely proportional to the concentration of bambara groundnut.

Practical applications

Vitamin A deficiency (VAD) is the leading cause of preventable blindness affecting many children and women of reproductive age globally. Provitamin A enriched foods can be developed from locally available provitamin A‐rich foods and their consumption promoted to help prevent VAD. In this study, recipes incorporating orange‐fleshed sweet potatoes and bambara groundnut were used to develop acceptable and shelf stable vitamin A enriched extruded snacks. The formulations and process used in this study can be adopted at commercial level to produce affordable snacks that can contribute towards reducing the burden of VAD. The results from this study can also be used in similar studies to develop nutrient enhanced extruded snacks.     

Assessment of iron bioavailability from twenty elite late‐maturing tropical maize varieties using an in vitro digestion/Caco‐2 cell model

An in vitro digestion/Caco‐2 cell model was used to assess iron bioavailability of twenty elite late‐maturing tropical maize varieties grown in three diverse agroecologies in West and Central Africa (WCA). Kernel‐iron concentration of the varieties, averaged across locations, varied from 19.2 to 24.4 mg kg^?1, while mean kernel‐zinc concentration ranged between 19.4 and 24.6 mg kg^?1. Significant differences in iron bioavailability were observed among varieties, but the environment had no significant effect. Mean bioavailable iron ranged between 14% below and 43% above the reference control variety, TZB‐SR. Variety DMR‐LSR‐Y with the highest concentrations of kernel‐iron and ‐zinc of 24–25 mg kg^?1 across the three locations had a similar quantity of bioavailable iron as the reference control, TZB‐SR. In the long run this variety could be potentially effective in reducing iron deficiency because of its high kernel‐iron. The most promising varieties were Mid‐altitude STR synthetic and ACR91SUWAN‐1‐SRC1. They had kernel‐iron and ‐zinc levels of 22–24 mg kg^?1 and bioavailable iron 24–36% higher than the reference control, TZB‐SR. Additional research is necessary to determine if the increases in kernel‐iron concentration and bioavailable iron observed in this study can significantly improve the iron status of individuals in WCA at risk for iron deficiency. Copyright © 2004 Society of Chemical Industry     

Nutritional quality of protein-enriched mumu– a traditional cereal food product

Protein‐enriched mumu was produced using maize supplemented with soybeans or groundnut. Supplementation of maize with groundnut or soybeans at the ratios of 85:15, 80:20, 75:25 and 70:30, respectively to produce maize:groundnut or maize:soybean blends was carried out. Proximate compositions and sensory evaluation of the blends were determined. The rat‐based protein efficiency ratio (PER) and body‐weight changes were used to assay the protein nutritive quality. Chemical compositions indicated significant increases (P < 0.05) in the protein and fat contents of the supplemented products. Soybean supplemented products had significantly (P < 0.05) higher positive body‐weight changes than groundnut supplemented products. The PER of 1.6–2.19 for the soybean supplemented products were also significantly higher (P < 0.05) than the corresponding PER of ?0.2 to ?1.5 for the groundnut supplemented products. Supplementation with soybeans beyond 25% did not further improve the protein quality.     

Effects of legume processing on calcium,iron and zinc contents and dialysabilities

Legumes are a good source of calcium, iron and zinc, but are also a source of phytates and dietary fibre components that can negatively affect the bioavailability of these minerals. To estimate the latter, an in vitro dialysis method can be applied that gives the dialysability of a mineral as an estimate of its availability for absorption. Calcium, iron and zinc contents and dialysabilities in three legumes (beans, chickpeas and lentils) and the effects of cooking treatments and industrial processing on these parameters were studied. Beans had the highest calcium content (1.54 g kg^?1 dry matter (DM)) and chickpeas the lowest iron content (46.9 mg kg^?1 DM), whilst the zinc contents were similar in all three raw legumes (33.7–36.9 mg kg^?1 DM). Traditional and microwave cooking reduced the mineral contents by 9.7–36.4% for calcium, 14.2–31% for iron and 11.1–28.9% for zinc. The dialysabilities of calcium with respect to the values for the raw products were also reduced by these cooking techniques. Industrially processed legumes had higher dialysabilities of calcium, iron and zinc than traditionally or microwave cooked legumes. © 2001 Society of Chemical Industry     

Preliminary study of L‐lysine production by Bacillus species using various agricultural by‐products

The production of lysine by Bacillus megaterium SP‐14 and Bacillus circulans Tx‐22 using agricultural by‐products as carbon and nitrogen sources was assessed. Among the carbon substrates used were potato, sorghum, plantain, millet, yam, cassava, and corn starches, while the nitrogen sources include cowpea, bambara‐nut, cotton seed, groundnut, soybean, and blood meals. The effect of natural nitrogen sources (1.0% w/v) and synthetic nitrogen source (4.0% w/v (NH₄)₂SO₄) on lysine production by the Bacillus strains showed that natural nitrogen sources gave better lysine yields.     

In-vitro multienzyme digestibility of protein of some plant source flours blended with bovine plasma protein concentrate

The in-vitro multienzyme protein digestibilities of the flours of maize, cassava, pigeon pea (Cajanus cajan), African yambean (Sphenostylis stenocarpa) and bambara groundnut (Vigna subterranea), blended with bovine plasma protein concentrate were investigated. The multienzyme system consists of trypsin, chymotrypsin and peptidase. It was found that the addition of bovine plasma protein concentrate improved the protein digestibility of the flours compared with flours without the additive. The digestibilities were increased by between 3% in bambara groundnut blended flour to about 10% in cassava blended flour. When the flours were wet-heat treated, the digestibilities further increased in all samples with increments between 7·5 % in bambara groundnut and 16·6% in cassava flour. Bovine plasma protein concentrate may be a good source of protein for the fortification of protein-deficient foods, particularly maize and cassava flours.     

Chemical,biological and sensory evaluation of pasta products supplemented with α‐galactoside‐free lupin flours

α‐Galactoside‐free lupin flour has been used to supplement durum wheat semolina flour in order to increase the nutritive value of pasta products. Supplemented pasta products had a shorter cooking time, higher cooking water absorption, cooking loss and protein loss in water than control pasta prepared with only semolina. Sensory evaluation of cooked pastas showed that products supplemented with 80 g kg^?1 of α‐galactoside‐free Lupinus angustifolius var. Emir flour or with 100 g kg^?1 of α‐galactoside‐free Lupinus angustifolius var. Troll flour showed the same acceptability by panellists as the semolina pasta. These levels of supplementation were selected for further studies. The cooked α‐galactoside‐free lupin/semolina pastas showed higher amounts of protein, dietary fibre, calcium, phosphorus, magnesium, zinc and antioxidant capacity than control pasta and a reasonable level of vitamin B₁, vitamin B₂ and vitamin E. Biological assessment of cooked pastas indicated that the true protein digestibility did not change after the fortification of semolina but protein efficiency ratio increased sharply in the pasta supplemented with α‐galactoside‐free lupin flours (2.07 and 1.92 for Emir and Troll lupin varieties, respectively) in comparison with the control pasta (1.11). It is concluded that the α‐galactoside‐free lupin flours are an adequate ingredient to improve the nutritional quality of pasta products without adding flatulent oligosaccharides. Copyright © 2006 Society of Chemical Industry     

Occurrence and infant exposure assessment of nitrates in baby foods marketed in the region of Lisbon,Portugal

Commercial baby food labelled as from organic or conventional origin, including vegetable-based baby foods, fruit purees and fruit juices (n?=?80), were analysed for nitrate content by an in-house validated HPLC method. Nitrate contents ranged from 5 to 230?mg?kg^?1 with a mean concentration of 102?mg?kg^?1 for vegetable-based baby foods, and a median of 5?mg?kg^?1 for both fruit purees and juices. One sample of vegetable-based baby food was higher than the legislated value (200?mg?kg^?1). There were no significant differences between average nitrate levels in analysed samples regarding both farming systems. The estimated nitrate intake through baby foods for a mean nitrate concentration of 47?mg?kg^?1 ranged between 0.5 (15% of ADI) and 1.3?mg?kg^?1?bw?day^?1 (35% of ADI). The ADI level was exceeded (107–146% of ADI) only for the 95th and 99th percentiles of nitrate concentration.     

Acceptability,storage stability and costing of α‐amylase‐treated maize–beans–groundnuts–bambaranuts complementary blend

The effects of α‐amylase treatment on physical properties, acceptability to mothers, and cost of roasted and extruded maize–beans–groundnuts–bambaranuts complementary porridge recipes were assessed prior to their industrial production. Storage stability of the extruded α‐amylase‐treated fortified blend was assessed at 2 weeks and 6 months by sensory evaluation, peroxide value, water activity and microbiological load. The use of α‐amylase at 0.04% w/w enhanced porridge acceptability and resulted in 88% and 122% increase in flour concentration for roasted and extrusion‐cooked porridge flour, respectively, while maintaining porridge viscosity at 1000‐fold lower than that of traditionally used porridges. The extrusion cooked blend was stable for 6 months. α‐Amylase application increased the unit cost of the developed blend by only 1.4%. The total cost was less than US $ 2 kg^?1, half the minimum price of commercially available complementary foods. Further work on marketing and the efficacy of this inexpensive food on growth of infants is warranted. Copyright © 2007 Society of Chemical Industry     

Boron concentrations in selected foods from borate‐producing regions in Turkey

As part of a large‐scale programme to investigate the health effects of exposure to borate minerals in Turkey, boron concentrations in vegetables, fruits and some other foods were determined. From all borate‐producing regions of the country, 22 species of fruit, 17 species of vegetable, 12 species of cereal, legume and oilseed, three species of herbs and six types of other food were collected in 1999 and analysed for boron concentrations using the Azomethine H method. The results were compared with 37 types of food collected from areas well distant from the borate‐producing areas. The total number of samples evaluated was 420. Pistachio (67.0 mg kg^?1) had the highest concentration of boron, followed by grape leaf (60.48 mg kg^?1), sour cherry (57.03 mg kg^?1), quince (38.78 mg kg^?1), peach (34.49 mg kg^?1), grape (20.70 mg kg^?1), green beans (19.49 mg kg^?1), unripe peach (18.92 mg kg^?1) and parsley (10.24 mg kg^?1) from the borate‐producing regions. A large number of foods contained boron at higher concentrations than those reported in the literature, most probably due to the high boron content of these Turkish soils. According to the results of t‐tests, the area itself does not have a significant effect (p > 0.05) on boron concentration in all foods evaluated so far. Copyright © 2003 Society of Chemical Industry     

On fumonisin incidence in monoculture maize under no‐till,conventional tillage and two nitrogen fertilisation levels

BACKGROUND: Fusarium ear rot and fumonisin contamination are serious problems for maize growers. The lack of maize genotypes highly resistant to fumonisin contamination emphasises the need for management strategies to prevent contamination by this mycotoxin. There are conflicting reports regarding no‐till and nitrogen (N) fertilisation practices in relation to the incidence of fumonisins. In this study the effect of no‐till compared with conventional tillage and of N fertilisation rates on fumonisin occurrence was investigated over three years in Northern Italy. RESULTS: The average contamination of grain by fumonisins B₁ and B₂ over the three years was significantly different, with a lower value in 2000 (516 µg kg^?1) than in the other years (5846 and 3269 µg kg^?1 in 2001 and 2002 respectively). Conventional tillage and no‐till treatments had no significant effect on the incidence of fumonisins. This finding suggests that above‐ground residues infected by Fusarium would not lead to an increase in fumonisin incidence. However, N fertilisation significantly increased fumonisin levels, by 99 and 70% in 2000 and 2001 respectively. CONCLUSION: Maize monoculture does not show a cumulative effect on the occurrence of fumonisins, while high rates of N fertiliser consistently result in elevated fumonisin levels. Both these effects can be influenced by annual meteorological fluctuations. Copyright © 2008 Society of Chemical Industry     

Protein and mineral content of a novel collection of wild and weedy common bean (Phaseolus vulgaris L)

Protein and total calcium, iron, and zinc were determined in 70 accessions of wild and weedy common bean (Phaseolus vulgaris L) from different sites in two Mexican states (Jalisco and Durango). Protein digestibility, essential amino acid profiles, tannins, phytic acid and extractable iron were determined in selected accessions. The phytate/zinc and the phytate × (calcium/zinc) molar ratios were also determined as predictors of zinc bioavailability. For comparative purposes, two cultivated common beans were included. The wild and weedy beans contained more protein and similar protein digestibility compared with cultivated samples. The contents of sulfur amino acids were low in all samples; additionally, beans from Jalisco had higher contents of sulfur amino acids than cultivated ones. Beans from Durango showed higher leucine, valine and aromatic amino acids contents than cultivated beans. Some wild and weedy beans from Jalisco and Durango showed high contents of calcium (7470 mg kg⁻¹), iron (280 mg kg⁻¹), and zinc (33.1 mg kg⁻¹). The phytic acid × (calcium/zinc) molar ratios of some wild and weedy beans were similar to those of cultivated beans. Amounts of extractable iron were in the order of 26–74%. © 2000 Society of Chemical Industry     

Nutritional composition and protein value of the baru (Dipteryx alata Vog.) almond from the Brazilian Savanna

BACKGROUND: The almond of the baru tree (Dipteryx alata Vog.), a native species of the Brazilian Savanna, is used in the gastronomy of the central western region of the country. There is relatively little information about the chemical composition and nutritional value of the baru almond, which was the motivation for this research. RESULTS: The baru almonds had high lipid (397–437 g kg^?1) and protein (238–281 g kg^?1) contents. There were differences in the amino acid score (AAS = 83–103%) and limiting amount of sulfur amino acids, depending on the origin of the almond. The protein value of the baru almond was higher than that of the peanut according to the relative net protein ratio (RNPR_Baru = 74%, RNPR_Peanut = 66%) and the protein digestibility‐corrected amino acid score (PDCAAS). The baru almond also had high iron (mean 48.1 mg kg^?1), zinc (mean 46.6 mg kg^?1) and dietary fibre (mean 115.8 g kg^?1) contents in relation to Dietary Reference Intakes. CONCLUSION: The baru almond has a high nutrient density and high content of quality protein. Furthermore, the lipid and protein contents and amino acid profile of the baru almond are representative of edible seeds and similar to those of true nuts. This almond can be used as a complementary source of protein and as an excellent option for a healthy diet. Copyright © 2010 Society of Chemical Industry     

Production of legume-fortified weaning foods

Maize and grain legumes (soybean, cowpea, and groundbean) and melon seeds (if needed) were pretreated and co-fermented for 28–36 h for production of high protein–energy legume-fortified weaning foods. They were dried at 60–66 °C for 15 h and milled into flours. Yields and chemical composition of the enriched foods were determined. Net yields in flour were 59.72, 64.76, 66.15, and 71.47%, respectively for weaning foods based on cowpea, groundbean, bambara groundnut and soybean compared with 52.35% for maize-based product (control). Losses of dry matters accounted for 12–17% mainly during milling of dry foods. Levels of protein and energy fluctuated between 15.55 and 19.30% and 17505.0 and 18726.4 kJ/ kg, respectively, and were higher than the recommended levels for weaning foods. Co-fermentation of plant raw materials, for example cereals and legumes appear as an appropriate technique for production of a high-protein–energy, socially acceptable and nutrient dense weaning foods at household levels in developing countries.     

Use of soaking to enhance the bioavailability of iron and zinc from rice‐based complementary foods used in the Philippines

Complementary foods used in the Philippines are predominantly rice‐based, although enrichment with mung beans and sesame seeds is recommended despite their high content of phytic acid, a potent inhibitor of iron and zinc absorption. We have investigated the effect of soaking on the inositol penta‐ (IP5) and hexaphosphate (IP6) (analysed by HPLC), zinc, iron and calcium (via AAS) content of rice‐based complementary foods with and without the addition of mung beans and sesame seeds. Soaking rice flour for 1, 6 and 12 h at 30 °C reduced the content of IP5 + IP6 by 60, 65 and 98% respectively, with only slight changes in zinc, iron and calcium. Levels of IP5 + IP6 were reduced by 10 and 47% by soaking mung bean flour, but not whole beans, for 1 and 6 h respectively. In conclusion, soaking can be used to reduce the IP5 and IP6 content of complementary foods based on mung bean flour and/or rice flour and thus enhance the bioavailability of iron and zinc. © 2002 Society of Chemical Industry     

Bioavailability of iron and zinc from multiple micronutrient fortified beverage premixes in Caco-2 cell model

Abstract: Iron and zinc deficiencies are the most prevalent nutrient deficiencies worldwide. They often coexist as the dietary factors, especially phytate, which impairs iron absorption also affects zinc absorption. Therefore, suitable strategies are required to control multiple micronutrient deficiencies in populations that subsist on high‐phytate foods such as the whole wheat flour based Indian bread (chapatti). The objective of the study, therefore, was to test the bioavailability of iron and zinc in 2 multiple micronutrient beverage premixes in the absence and presence of chapatti. The premix‐1 contained iron, zinc, and vitamin A while premix‐2 contained all micronutrients in premix‐1, plus folic acid and ascorbic acid. Ferritin induction and ⁶⁵Zn uptake were assessed using coupled in vitro digestion/Caco‐2 cell line model as the surrogate markers of iron and zinc bioavailability, respectively. The results show that iron bioavailability from premixes‐1 and 2 was similar in the absence of chapatti. However, premix‐2 showed significantly higher iron bioavailability compared to premix‐1 in the presence of chapatti. In contrast, the zinc uptake was similar from both premixes‐1 and 2 in the absence or presence of chapatti. These results suggest that both the premixes provide bioavailable minerals, but premix‐2 appears to be promising in the presence of foods that have high phytate.     

Simple determination of formaldehyde in fermented foods by HS‐SPME‐GC/MS

We describe an automatic method to detect formaldehyde (FA) in some fermented foods. This method is based on derivatisation with 2,2,2‐trifluoroethylhydrazine (TFEH) and consecutive headspace solid‐phase micro‐extraction and gas chromatography‐mass spectrometry. FA in food reacted for 30 min at 40 °C with 2,2,2‐TFEH in a headspace vial, and the formed FA‐TFEH derivative was simultaneously vaporised and adsorbed on 85‐μm carboxen–polydimethylsiloxane. Under the established condition, the limit of detection was 0.1 μg kg^?1 by using 1.0‐g solid food and 1.0‐mL liquid food, and the relative standard deviation was less than 10% at FA concentrations between 0.050 and 0.500 mg kg^?1. The concentrations of FA in several traditional Korean foods including gimchi, watery radish gimchi, soybean paste, red pepper paste, soy sauce and bean‐paste soup were measured. All food samples had detectable levels of FA (0.104–13.05 mg kg^?1).     

Determination of acrylamide content of food products in Korea

Acrylamide (AA) contents of commercial market‐purchased foods and of traditional home‐cooked Korean foods were investigated. The effect of cooking method on AA amount in potatoes was also studied. AA contents of roasted barley and corn ranged from 116 to 449 µg kg^?1 and of chips ranged from 12 to 3241 µg kg^?1, representing a very high variation in AA contents among tested samples. Lower levels of AA were found in wheat flour chips compared to potato chips. AA contents of ramen noodles were below 37 µg kg^?1, whether they contained potato starch or not. The AA contents of Korean home‐cooked oil fried foods increased in the following order: yakwa < whole deep‐fried sea tangle < ground and deep‐fried lotus root < ground and pan‐fried lotus root < French fries < ground and pan‐fried potato. Lotus root and garlic also had the potential to produce AA during cooking. Pre‐treatment such as grinding, boiling, freezing and thawing increased the AA formation in oil‐fried potato. Temperature was more influential than time on AA formation during deep‐oil frying. Removing water‐soluble fractions reduced AA content of cooked potatoes. Copyright © 2006 Society of Chemical Industry     

Studies on bambara groundnut flour performance in Okpa preparation

Bambara groundnut flours of different particle sizes were prepared after bean seeds had been cold‐soaked and/or germinated, dried, milled and sieved. The flours were used to prepare okpa (local dish prepared by steaming mashed bambara groundnut) and their sensory properties determined. Viscosity of the flour pastes, before steaming, were also determined. Results showed that bambara groundnut flours from both germinated and cold‐soaked beans could be used in preparing good quality okpa and, therefore, remove all the problems involved in preparing the raw beans for okpa‐making as is done traditionally. Particle size appeared to play a major role in obtaining good okpa; therefore flours intended for okpa preparation should be such that 66, 86 and 96%, respectively, of cold‐soaked bean flour or 58, 78 and 91%, respectively, of germinated bean flour, after 1, 3 and 5 milling passes, should be in the particle range 1.5–4.5 × 10^?4 m. Slightly higher amounts of the coarse (6.0 × 10^?4 m) particles are needed in the germinated bean flours to compensate for the breakdown of starch and proteins, the gelling agents in bambara groundnut. Copyright © 2004 Society of Chemical Industry