Potential of non‐GMO biofortified pearl millet (Pennisetum glaucum) for increasing iron and zinc content and their estimated bioavailability during abrasive decortication

Two non‐GMO biofortified and one traditional pearl millet varieties were compared in abrasive decortication studies to evaluate their potential for increasing iron and zinc content. The phytate‐to‐mineral ratios were used to estimate mineral bioavailability. Iron and zinc contents in the biofortified varieties Tabi and GB8735 were two to threefold higher than in the traditional variety. Iron content reached 7.2 and 6.7 mg per 100 g DM in the biofortified varieties, which corresponds to the target values of biofortification programs. Zinc content was, respectively, 5.6 and 4.1 mg per 100 g DM in the GB8735 and Tabi varieties. Because of the presence of phytate and other chelating factors that were only partially removed during decortication, there was no improvement in iron bioavailability in the biofortified varieties. But whatever extraction rate, phytate‐to‐zinc ratios ranged between 6 and 18; zinc absorption could be improved by using these biofortified varieties for food processing.     

Use of Soaking and Enrichment for Improving the Content and Bioavailability of Calcium, Iron, and Zinc in Complementary Foods and Diets of Rural Malawian Weanlings

ABSTRACT: Effect of enrichment and aqueous extraction on Ca, Fe, Zn, hexa (IP-6), and penta (IP-5) inositol phosphate content of slurries or porridges prepared from fresh and stored maize flour (MF) was investigated. IP-5 + IP-6 in fresh MF was higher than stored but after soaking in water and decanting, more IP-5 + IP-6 was lost from fresh MF, so final [Phy] [Zn] molar ratios became similar (18 compared with 20). Enriching MF porridges with fish flour increased Ca and Zn, and after soaking in water and decanting reduced IP-5 + IP-6, thus decreasing [Phy]:[Zn], [Phy]:[Fe], and [Phy]:[Ca] molar ratios. Using Ca, Fe, Zn, IP-5 + IP-6 values for soaked enriched porridges, simulated Ca, Fe, and Zn intakes for Malawian infants were higher, but still inadequate.     

Selecting desirable micronutrient fortificants for plant‐based complementary foods for infants and young children in low‐income countries

The World Health Organization (WHO) recommends that both breast‐fed and non‐breast‐fed children are fed micronutrient fortified complementary foods designed to meet their high nutrient requirements from aged 6 to 23 months of age. This paper summarises the steps recommended by WHO/FAO to identify the country‐specific micronutrient shortfalls in complementary diets and establish desirable levels of bioavailable fortificants for centrally processed plant‐based complementary foods for infant and young child feeding. The goal of the WHO/FAO guidelines is to achieve a desirably low prevalence of inadequate micronutrient intakes in the target group whilst simultaneously ensuring minimal risk of excessive intakes. © 2014 Society of Chemical Industry     

Bioavailability of zinc from infant foods by in vitro methods (solubility,dialyzability and uptake and transport by Caco‐2 cells)

The aim of this study was to evaluate the bioavailability of zinc from infant foods (adapted, follow‐up and toddler milk‐based formulas and fruit juices containing milk and cereals, FMC) using solubility, dialyzability and a model combining simulated gastrointestinal digestion and zinc uptake and transport by Caco‐2 cells. The greater solubility of zinc from infant formulas compared with fruit juices (FMC) could be due to the greater casein phosphopeptide content resulting from casein hydrolysis. The highest zinc dialysis percentage corresponded to FMC, which on the other hand had the lowest zinc contents of the analyzed samples. The presence of organic acids in samples of this kind favors the formation of soluble low molecular weight complexes with zinc, thereby increasing the solubility of the latter. Bifidobacterium addition exerted no effect upon zinc bioavailability. Transport and uptake efficiency in Caco‐2 cells were significantly greater for toddler formulas, which presented the highest casein contents. The greater efficiency in zinc transport and uptake from the powdered toddler formula compared with the liquid formulation could be explained by the effect of Maillard reaction products. Copyright © 2006 Society of Chemical Industry     

Dephytinisation of Sangak and Barbari bread made from different extraction rate flours increases iron and zinc bioaccessibility in Caco‐2 cells

Bread is a staple food in many countries and an important source of iron and zinc. The bioavailability of these minerals is generally low because of the content of phytic acid. Traditional Iranian breads were prepared with flours of different extraction rates, Sangak at 93% and Barbari at 82%. Breads were dephytinised by addition of Aspergillus niger phytase during in vitro digestion. The effect upon iron and zinc bioaccessibility in the Caco‐2 cell model was investigated. The cellular uptake of iron and zinc was lower from Sangak, compared to Barbari, despite higher mineral content in Sangak. Dephytinisation of both breads increased iron uptake in the Caco‐2 cells (0.65 vs. 1.64 in Sangak and 0.77 vs. 1.97 ng mg^?1 protein in Barbari). Zinc uptake increased from 0.98 to 2.8 in Sangak and from 1.4 to 2.9 ng mg^?1 protein in Barbari. Thus, dephytinisation substantially improves iron and zinc bioaccessibility.     

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     

Production of maize–bambara groundnut complementary foods fortified pre‐fermentation with processed foods rich in calcium,iron, zinc and provitamin A

BACKGROUND: Maize–bambara groundnut complementary foods are deficient in calcium, iron, zinc and vitamin A. Food‐to‐food fortification could be cheaper, safer and more easily adopted by local communities compared to the use of chemically pure compounds and vitamins to enrich such foods. RESULTS: Maize–bambara groundnut complementary foods fortified for iron, zinc, calcium and vitamin A by blending with a multi‐mix (1.41:1:2.25, w/w) of processed roselle calyces, cattle bones, and red palm oil in a 1:2.1 (w/w) ratio showed significant increases in calcium, iron, zinc and vitamin A contents of 3.26–4.225, 0.083–0.134 and 0.015–0.017 g kg^?1 and 4855.3–7493.7 µgRE kg^?1, respectively. CONCLUSION: The maize–bambara groundnut foods had calcium, iron, zinc and vitamin A contents that satisfy the proposed nutrient requirements for infants. Only the maize–bambara groundnut and maize–bambara groundnut malt fermented by backslopping [(MB)_b and (MB_m)_b] containing red palm oil emulsified with Brachystegia eurycoma had calcium contents significantly (P < 0.05) higher than Nutrend, a complementary food produced by Nestle (Nigeria) PLC. These products are from raw materials produced in commercial quantities by rural farmers using household level technologies which the rural and urban poor can more easily access in order to reduce micronutrient malnutrition. Copyright © 2010 Society of Chemical Industry     

Development of a three‐tier in vitro system,using Caco‐2 cells,to assess the effects of lactate on iron uptake and transport from rye bread following in vitro digestion

A three‐tier Caco‐2 cell system was developed to assess simultaneously iron dialysability, uptake and transport across the Caco‐2 monolayer from an in vitro digested food matrix. The effect of lactate (0–200 mmol L⁻¹) on iron absorption from rye bread subjected to simulated peptic (pH 5.5) and pancreatic digestion (pH 6.5) was investigated to model absorption pre and post the sphincter of Oddi. Lactate increased dialysability (11.8%, P < 0.05) in peptic digests whereas it reduced it in pancreatic digests (4.9%, P < 0.001). Iron uptake from the peptic digests was in the region of 39–76 pmol mg⁻¹ protein whereas it decreased from 281 to 51 pmol mg⁻¹ protein in pancreatic digests. Iron transport was calculated for the peptic digests from [¹⁴C]polyethylene glycol movement and only at 200 mmol L⁻¹ lactate was there any detectable transcellular transport (180 pmol mg⁻¹ protein, P < 0.05). Iron absorption was positively correlated to dialysable iron for both digests (R² = 0.48 and 0.41, respectively, P < 0.01) and the effect of lactate was therefore associated mainly with iron bioaccessibility. The three‐tier system showed the potential to obtain detailed insight into each step involved in iron transport across the monolayer from a food mixture. Copyright © 2006 Society of Chemical Industry     

Development of ready‐to‐eat rice starch‐based puffed products by coupling freeze‐drying and microwave

The rice starch mixtures with varying amylose contents (AC) of 0.12–19.00% weight were prepared by mixing waxy and nonwaxy rice starches. The 5% rice bran oil shortening was added in the starch paste. After gelatinisation, thin slabs of starch pastes were aged at 4 °C for 24 h. The aged slabs were dried by freeze‐drying to obtain 25% moisture content. A microwave oven set to 600 J s^?1 for 90 s was then used for puffing. The crucial factors affecting the snack purchase were texture and nutrition. The relative crystallinity and retrogradation enthalpy (?H_r) of freeze‐dried pellets increased with increasing the AC. From using a differential scanning calorimeter (DSC), endotherms of pellets were shown only when AC > 0.12%. An amylose–lipid complex was shown in pellets with AC ≥ 9.00%. Relationships between the AC and all puffed product properties were linear. Increasing AC provided greater hardness, fracturability, bulk density, but lower expansion ratio. From the sensory evaluation, the panellists preferred the puffed products with 9.00% AC. Increasing the AC gave higher crispness, hardness, brittleness, air cell opacity and density, but resulted in less puffiness. Thus, the microwave drying has the potential to puff a healthy expanded snack but giving the desirable properties depends on AC.     

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.     

Comparison of enhancement in bioaccessible iron and zinc in native and fortified high‐phytate oilseed and cereal composites by activating endogenous phytase

In developing countries, iron and zinc deficiencies are mostly attributable to poor bioavailability of iron and zinc. The study aimed at enhancing the bioaccessibility of minerals in high‐phytate oilseed and cereal flour mixes by activating the intrinsic phytase of wheat flour. The flour mixes were fortified with iron and zinc separately for comparison. The flour mixes were incubated at optimum conditions of temperature and pH for phytase activation. Phytase activation enhanced bioaccessible iron by 43–162% in native and 40–168% in fortified wheat–soya, 83–192% in native and 97–240% in fortified wheat–groundnut flour mixes in relation to control flour mixes. Bioaccessible zinc was enhanced by 87–183% in native and 30–113% in fortified wheat–soya, 31–65% in native and 61–186% in fortified wheat–groundnut flour mixes. Endogenous phytase activation was effective in enhancing bioaccessibility of iron and zinc in native and fortified flour composites economically.     

Short‐term feeding of fermentable dietary fibres influences the gut microbiota composition and metabolic activity in rats

This study investigated the effects of dietary fibres on gut bacterial abundance and metabolic activity in rats fed short‐term. Faecal samples from rats fed for 7 days showed differences in the effects of dietary fibres on gut bacterial populations. Broccoli fibre, inulin, potato fibre and potato resistant starch significantly increased the faecal Bacteroides‐Prevotella‐Porphyromonas group compared with cellulose. Growth of pathogenic bacteria such as Clostridium perfringens, Escherichia coli and Enterococcus spp. was decreased significantly in rats fed barley β‐glucan, citrus pectin, inulin and broccoli fibre diets. An increase in Bifidobacterium spp. and butyric acid levels, the so‐called bifidogenic and butyrogenic effects, was observed in rats fed inulin and potato fibre diets. Organic acid concentrations and polysaccharide contents in the rat faeces confirm the fermentability of dietary fibres in the gut. This study demonstrates the positive effects of plant‐sourced dietary fibres on gut microbiota composition and metabolic activity.     

Changes in mineral absorption inhibitors consequent to fermentation of Ethiopian injera: implications for predicted iron bioavailability and bioaccessibility

Possible changes in mineral bioavailability during processing of different types of injera sampled in Ethiopian households were assessed using different methods: phytic acid/mineral molar ratio, absorption prediction algorithm and in vitro availability measurements. Most foods analysed were rich in iron, but most of the iron likely resulted from soil contamination. The highest iron, zinc and calcium contents were found in teff–white sorghum (TwS) injera and flour. The lowest phytic acid/Fe and phytic acid/Zn molar ratios were found in barley–wheat (BW) and wheat–red sorghum (WrS) injeras. Although ideal phytic acid/Fe molar ratios (<0.4) were found in BW and WrS injeras, no significant difference between in vitro iron bioaccessibility and algorithm predicted absorption was observed. In injera, phytic acid degradation alone is unlikely to improve iron bioavailability, suggesting interactions with other absorption inhibitors. The use of phytic acid/Fe molar ratios to predict bioavailability may thus be less appropriate for iron‐contaminated foods.     

Computer vision‐based analysis of foods: A non‐destructive colour measurement tool to monitor quality and safety

Computer vision‐based image analysis has been widely used in food industry to monitor food quality. It allows low‐cost and non‐contact measurements of colour to be performed. In this paper, two computer vision‐based image analysis approaches are discussed to extract mean colour or featured colour information from the digital images of foods. These types of information may be of particular importance as colour indicates certain chemical changes or physical properties in foods. As exemplified here, the mean CIE a^* value or browning ratio determined by means of computer vision‐based image analysis algorithms can be correlated with acrylamide content of potato chips or cookies. Or, porosity index as an important physical property of breadcrumb can be calculated easily. In this respect, computer vision‐based image analysis provides a useful tool for automatic inspection of food products in a manufacturing line, and it can be actively involved in the decision‐making process where rapid quality/safety evaluation is needed. © 2013 Society of Chemical Industry