Calcium absorption from corn tortilla is relatively high and is dependent upon calcium content and liming in Mexican women

Sustainable Process for Tortilla Production Using Ohmic Heating with Minimal Impact on the Nutritional Value, Protein, and Calcium Performance

The nixtamalization process used for tortilla production entails extended processing time and generates pollutant effluents. Ohmic heating (OH) is an emerging technology that uses an alternating electric current for rapid and uniform food heating and mitigates effluent concerns. However, gaps exist in nutrient bioavailability studies. In this work, we assessed OH's impact on tortilla nutritional value, protein, and calcium using a rat model. Twenty-five male Wistar rats were fed one of four diets for 21 days: raw corn (RC) as an experimental control, OH-processed tortillas (OHTs), traditionally processed tortillas (TPTs), commercial tortillas (CTs), and a casein diet (CD) as a growth control. Despite similar protein and macronutrient profiles, OH significantly enhanced insoluble fiber content. The weight gain sequence was OHTs > TPTs > CTs > RC. OHTs exhibited superior protein digestibility (88.52%), which was 3% higher than other diets. The serum albumin (2.63-2.73 g/dL) indicated moderate malnutrition due to the tortilla's lower protein content. Nonetheless, the protein efficiency ratio (1.2-1.74) showed no significant difference from TPTs. Bone characteristics and fracture strength resembled the tortilla-fed groups, surpassing RC. X-ray diffraction and scanning electron microscopy confirmed that the OHT and TPT diets improved male rat bone thickness and crystallinity. The findings suggest the potential for OH as an eco-friendly tortilla production method, maintaining nutritional value comparable to traditional methods.

Improving Calcium Status of Women: Results of a Study of Bio-Availability of Calcium From Slaked Lime Fortified Rice

BACKGROUND

Fortification of rice with slaked lime is an acceptable and inexpensive way to combat calcium (Ca) deficiency. However, bioavailability of calcium after intake of slaked lime fortified rice is yet to be investigated.

OBJECTIVE

To measure the fractional absorption of Ca (FAC) from slaked lime fortified cooked rice.

DESIGN

We conducted an experimental study using stable isotopes of Ca to measure FAC during a single morning test meal containing rice fortified with slaked lime. Participants (n = 22) were given slaked lime fortified rice 3 times a day for 4 days. On the morning of the fifth day, the participants were served the same amount of rice as previous the 4 days at the breakfast test meal with an accurately measured amount of ⁴⁴Ca stable isotope oral tracer followed by an intravenous injection of ⁴²Ca. Urine was collected over the next 24 hours in 3 consecutive 8-hour pools. Fractional absorption of Ca was calculated from the measurement of the relative enrichment of the of each administered tracer ⁴⁴Ca and ⁴²Ca using inductively coupled plasma mass spectrometry.

RESULTS

The mean Ca concentration in the test meal was 879.5 ± 152.9 µg/g with a coefficient of variance (CV) of 17.2%. Although Ca absorption efficiency decreases with higher calcium intake, the total amount of calcium absorbed from test meal using FAC = 0.391 calculated from the third 8-hour urine pool was 69.0 (CV of 15.6) mg.

CONCLUSIONS

We showed that one-fifth of daily calcium recommendation for women of reproductive age could be met by ingesting ∼200 g cooked slake fortified rice.

Vegan nutrition: a preliminary guide for health professionals

Since the beginning of the 21st century, interest in vegan diets has been rapidly increasing in most countries. Misconceptions about vegan diets are widespread among the general population and health professionals. Vegan diets can be health-promoting and may offer certain important advantages compared to typical Western (and other mainstream) eating patterns. However, adequate dietary sources/supplements of nutrients of focus specific to vegan diets should be identified and communicated. Without supplements/fortified foods, severe vitamin B12 deficiency may occur. Other potential nutrients of focus are calcium, vitamin D, iodine, omega-3 fatty acids, iron, zinc, selenium, vitamin A, and protein. Ensuring adequate nutrient status is particularly important during pregnancy, lactation, infancy, and childhood. Health professionals are often expected to be able to provide advice on the topic of vegan nutrition, but a precise and practical vegan nutrition guide for health professionals is lacking. Consequently, it is important and urgent to provide such a set of dietary recommendations. It is the aim of this article to provide vegan nutrition guidelines, based on current evidence, which can easily be communicated to vegan patients/clients, with the goal of ensuring adequate nutrient status in vegans.

Calcium Biofortification of Crops-Challenges and Projected Benefits

Despite Calcium (Ca) being an essential nutrient for humans, deficiency of Ca is becoming an ensuing public health problem worldwide. Breeding staple crops with higher Ca concentrations is a sustainable long-term strategy for alleviating Ca deficiency, and particular criteria for a successful breeding initiative need to be in place. This paper discusses current challenges and projected benefits of Ca-biofortified crops. The most important features of Ca nutrition in plants are presented along with explicit recommendations for additional exploration of this important issue. In order for Ca-biofortified crops to be successfully developed, tested, and effectively implemented in most vulnerable populations, further research is required.

Effect of maize processing methods on the retention of minerals, phytic acid and amino acids when using high kernel-zinc maize

High kernel-zinc maize varieties are available to consumers in several countries in Latin America to contribute to increase the zinc intake of their populations. Minerals, phytic acid and amino acids retention were measured after processing six maize varieties including three high kernel-zinc, one quality protein maize and two conventional maize. Grain for each variety was processed into tortillas, arepas and mazamorra, common maize dishes in the region. To evaluate the effect of processing kernel-zinc maize varieties on zinc retention, varieties were grouped in zinc biofortified maize (ZBM) and non-ZBM. Iron, zinc, phytic acid, tryptophan and lysine concentrations in non-processed maize were 17.1–19.1 ​μg/g DW, 23.9–33.0 ​μg/g DW, 9.9–10.0 ​mg/g DW, 0.06–0.08% and 0.27–0.37%, respectively. In tortillas, the iron, zinc, phytic acid and lysine content did not change (p ​< ​0.05) compared to raw grain, while tryptophan decreased by 32%. True retention of iron in arepas and mazamorra was 43.9 and 60.0%, for zinc 36.8 and 41.3%, and for phytic acid 19.3 and 25.1%. Tortillas had higher zinc retention than arepas and mazamorra due to use of whole grain in the nixtamalization process. Therefore, to contribute to higher zinc intake, nixtamalized tortilla prepared with biofortified zinc maize is recommended. Additionally, promotion of whole grain flour to prepare arepas should be explored to enhance the intake of minerals that are usually confined to aleurone layers and germ.

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High kernel-zinc maize varieties are available to consumers in several Latin American countries.

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In nixtamalized tortillas, the iron, zinc, phytic acid and lysine content did not chage compared to raw grain.

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Nixtamalized tortillas prepared with biofortified zinc maize is recommended.

Current calcium fortification experiences: a review

Low dietary calcium is very common in many populations, contributing to nutritional rickets/osteomalacia in children/adults and increasing the risk of several health problems. Calcium is a nutrient of concern as the recommended nutrient requirements are difficult to meet in the absence of dairy products. The provision of culturally acceptable calcium-fortified foods may improve calcium intake when it is a feasible and cost-effective strategy in a particular setting. This landscape review was conducted in 2019 and describes current calcium fortification efforts and lessons learned from these experiences. Worldwide, the United Kingdom is the only country where calcium fortification of wheat flour is mandatory. It is estimated that this fortified staple ingredient contributes to 13-14% of calcium intake of the British population. Other items voluntary fortified with calcium include maize flour, rice, and water. Current calcium fortification programs may lack qualified personnel/training, clear guidelines on implementation, regulation, monitoring/evaluation, and functional indicators. Also, the cost of calcium premix is high and the target groups may be hard to reach. There is a lack of rigorous evaluation, particularly in settings with multiple micronutrient programs implemented simultaneously, with low quality of the evidence. Further research is needed to assess the impact of calcium fortification programs.

Emerging techniques assisting nixtamalization products and by-products processing: an overview

The production of worldwide nixtamalized products has increased in Latin American countries over the last years. For a better maize handling and exploitation of its nutritional elements, maize is subjected to a nixtamalization pretreatment protocol, which produces meaningful chemical, nutritional and quality changes in maize and its derived products, but large amounts of its primary by-product, well-known as 'nejayote', are also produced. Importantly, nejayote is usually discarded into the urbanized sewage with minimal treatment. Today, according to the recent research reports, new emerging techniques and protocols have been implemented to improve the nixtamalization products and by-products processing. New valorization approaches and biotechnological developments (including biotransformations) toward the reuse of nejayote have been developed according to its considerable content of biomolecules. Therefore, the goal of this paper is to provide a comprehensive review of the main development works at assisting nixtamalization products and by-products processing. Herein, particular attention is paid to experimental insights dealing with the valorization of nejayote.

Home Fortification of Rice With Lime: A Novel Potential Way to Reduce Calcium Deficiency in Bangladesh

BACKGROUND

In order to improve calcium status, fortified rice should have acceptable organoleptic properties of that food.

OBJECTIVE

We aimed to assess whether home fortification of rice with slaked lime can increase calcium content of rice and whether this fortified rice is well tolerated in a nutritionally at-risk population.

METHODS

This experimental study measured the calcium content of rice cooked with different concentration of lime and assessed the acceptability of fortified rice among 400 women and children. Each participant received fortified rice with one of five concentrations of lime (0, 2.5, 5, 7.5 or 10 gm per 500 gm of rice), with or without additional foods (lentil soup or fried green papaya). All participants were asked to score the organoleptic qualities on a hedonic scale.

RESULTS

Analysis showed that rice calcium content increased in a dose- response manner with increased lime during cooking (76.03, 205.58, 427.55, 614.29 and 811.23 mg/kg for given lime concentrations). Acceptability of the meal was greater when additional foods were served with rice at all lime concentrations. In both groups, the 7.5M arm reported highest overall acceptability (children, 6.25; women 6.10). This study found significant association between overall acceptability (different concentrations of lime mixed rice; with/without additional foods) and between groups (women vs. children) (p value = < 0.001) where-as no association was found within groups.

CONCLUSIONS

Lime-fortified rice can be feasible considering the calcium uptake of rice and organoleptic character. Further research on bioavailability can establish a solid foundation that will support design of an effective intervention to reduce calcium deficiency in this population.

Calcium Deficiency in Bangladesh: Burden and Proposed Solutions for the First 1000 Days

BACKGROUND

Bangladesh incurs among the highest prevalence of stunting and micronutrient deficiencies in the world, despite efforts against diarrheal disease, respiratory infections, and protein-energy malnutrition which have led to substantial and continuous reductions in child mortality over the past 35 years. Although programs have generally paid more attention to other micronutrients, the local importance of calcium to health has been less recognized.

OBJECTIVE

To synthesize available information on calcium deficiency in Bangladesh in order to inform the design of an effective national calcium program.

METHODS

We searched 3 online databases and a multitude of survey reports to conduct a narrative review of calcium epidemiology in Bangladesh, including population intake, determinants and consequences of deficiency, and tested interventions, with particular reference to young children and women of childbearing age. This was supplemented with secondary analysis of a national household survey in order to map the relative extent of calcium adequacy among different demographics.

RESULTS

Intake of calcium is low in the general population of Bangladesh, with potentially serious and persistent effects on public health. These effects are especially pertinent to young children and reproductive-age women, by virtue of increased physiologic needs, disproportionately poor access to dietary calcium sources, and a confluence of other local determinants of calcium status in these groups.

CONCLUSION

A tablet supplementation program for pregnant women is an appealing approach for the reduction in preeclampsia and preterm birth. Further research is warranted to address the comparative benefit of different promising approaches in children for the prevention of rickets.

Pellagra and alcoholism: a biochemical perspective

Historical and clinical aspects of pellagra and its relationship to alcoholism are reviewed from a biochemical perspective. Pellagra is caused by deficiency of niacin (nicotinic acid) and/or its tryptophan (Trp) precursor and is compounded by B vitamin deficiencies. Existence on maize or sorghum diets and loss of or failure to isolate niacin from them led to pellagra incidence in India, South Africa, Southern Europe in the 18th century and the USA following the civil war. Pellagra is also induced by drugs inhibiting the conversion of Trp to niacin and by conditions of gastrointestinal dysfunction. Skin photosensitivity in pellagra may be due to decreased synthesis of the Trp metabolite picolinic acid → zinc deficiency → decreased skin levels of the histidine metabolite urocanic acid and possibly also increased levels of the haem precursor 5-aminolaevulinic acid (5-ALA) and photo-reactive porphyrins. Depression in pellagra may be due to a serotonin deficiency caused by decreased Trp availability to the brain. Anxiety and other neurological disturbances may be caused by 5-ALA and the Trp metabolite kynurenic acid. Pellagra symptoms are resolved by niacin, but aggravated mainly by vitamin B6. Alcohol dependence can induce or aggravate pellagra by inducing malnutrition, gastrointestinal disturbances and B vitamin deficiencies, inhibiting the conversion of Trp to niacin and promoting the accumulation of 5-ALA and porphyrins. Alcoholic pellagra encephalopathy should be managed with niacin, other B vitamins and adequate protein nutrition. Future studies should explore the potential role of 5-ALA and also KA in the skin and neurological disturbances in pellagra.

Boundary development in the field of international nutrition science

Using a sociological approach that elaborates on key observations of institutional entrepreneurs in international nutrition, this paper explores institutional boundaries and boundary work in international nutrition. Sociological concepts of "boundary making" and "situated knowledge" are applied to the boundaries between the nutrition sciences and lay nutrition knowledge in nutrition intervention. These concepts allow an analysis of how nutrition science creates boundaries between its field and other sciences and between nutrition as a science and other nutrition practices, providing additional perspective on current challenges in global food security and malnutrition. Analysis of boundary processes in international nutrition can also illuminate the development of "implementation" or "delivery science" in the field of international nutrition as it attempts to strengthen effectiveness of global efforts to reduce malnutrition. Although some risk taking in the academic world is rewarded, the analysis indicates that there are underlying processes that may inhibit full partnership with local people in the course of intervention work that builds scientific nutrition knowledge. As nutrition science becomes increasingly central to development, the boundaries that are reinforced by digging in heels over the implementation of programs with little local input or softened by inviting local stakeholders to publicly consider the problems in global nutrition together are important to consider in helping to create directions that favor viable solutions.

Bioavailability of zinc oxide added to corn tortilla is similar to that of zinc sulfate and is not affected by simultaneous addition of iron

BACKGROUND

Corn tortilla is the staple food of Mexico and its fortification with zinc, iron, and other micronutrients is intended to reduce micronutrient deficiencies. However, no studies have been performed to determine the relative amount of zinc absorbed from the fortified product and whether zinc absorption is affected by the simultaneous addition of iron.

OBJECTIVE

To compare zinc absorption from corn tortilla fortified with zinc oxide versus zinc sulfate and to determine the effect of simultaneous addition of two doses of iron on zinc bioavailability.

METHODS

A randomized, double-blind, crossover design was carried out in two phases. In the first phase, 10 adult women received corn tortillas with either 20 mg/kg of zinc oxide added, 20 mg/kg of zinc sulfate added, or no zinc added. In the second phase, 10 adult women received corn tortilla with 20 mg/kg of zinc oxide added and either with no iron added or with iron added at one of two different levels. Zinc absorption was measured by the stable isotope method.

RESULTS

The mean (+/- SEM) fractional zinc absorption from unfortified tortilla, tortilla fortified with zinc oxide, and tortilla fortified with zinc sulfate did not differ among treatments: 0.35 +/- 0.07, 0.36 +/- 0.05, and 0.37 +/- 0.07, respectively. The three treatment groups with 0, 30, and 60 mg/kg of added iron had similar fractional zinc absorption (0.32 +/- 0.04, 0.33 +/- 0.02, and 0.32 +/- 0.05, respectively) and similar amounts of zinc absorbed (4.8 +/- 0.7, 4.5 +/- 0.3, and 4.8 +/- 0.7 mg/day, respectively).

CONCLUSIONS

Since zinc oxide is more stable and less expensive and was absorbed equally as well as zinc sulfate, we suggest its use for corn tortilla fortification. Simultaneous addition of zinc and iron to corn tortilla does not modify zinc bioavailability at iron doses of 30 and 60 mg/kg of corn flour.

A pilot randomized controlled trial of oral calcium and vitamin D supplementation using fortified laddoos in underprivileged Indian toddlers

BACKGROUND/OBJECTIVES

Low habitual dietary calcium intake and vitamin D deficiency are common among Indian children. Using 'laddoo', an Indian snack, as a vehicle for administering calcium and vitamin D supplements, a randomized double-blind controlled trial was conducted for 12 months to assess its efficacy on total body less head (TBLH) bone mineral content (BMC) in underprivileged toddlers.

SUBJECTS/METHODS

A total of 60 toddlers (mean age 2.7±0.52 years, boys=31) were randomized to two groups, (i) study group receiving one calcium fortified laddoo (cereal-legume snack) containing 405 mg calcium per day and (ii) control receiving a non-fortified laddoo, containing 156 mg of indigenous calcium. Both groups also received a laddoo fortified with 30,000 IU of vitamin D(3) per month. Outcome measures included TBLH bone area (BA) and TBLH BMC by GE-Lunar DPX Pro Pencil Beam Dual-Energy X-ray absorptiometry.

RESULTS

At baseline, mean energy, protein and calcium intakes were 71, 72 and 47% of Indian Recommended Dietary allowances. In all, 87 and 83% toddlers were hypocalcaemia and vitamin D deficient, respectively. Mean TBLH BMC was 289.5±45.8 g. Post supplementation, mean TBLH BMC of study group showed a significantly greater (P<0.01) increase of 35% as against 28% in controls and the difference remained significant after adjusting for vitamin D status, calcium intake, height and TBLH BA.

CONCLUSIONS

Daily supplementation with calcium fortified laddoo, and monthly vitamin D supplement resulted in a significant increase in TBLH BMC of underprivileged toddlers. We believe that such strategies have the potential of addressing nutritional problems in developing countries.

Calcium fortificants: overview and strategies for improving calcium nutriture of the U.S. population

Despite more than 20 y of awareness of the importance of calcium to health, U.S. calcium intakes remain suboptimal. Fortification of foods with shortfall nutrients is probably the optimal strategy for dealing with widespread nutrient deficiencies, as it has the best chance of reaching the population segments most at risk, as contrasted with attempts at changing individuals' food choices or relying on voluntary supplement taking. Given the wide array of potential calcium fortificants and fortification levels, there is not much to guide manufacturers interested in improving the nutritional value of their products. In this review, we assemble the calcium salts/complexes that have been used or proposed for use as fortificants and describe certain of their measured characteristics that relate to incorporation into foods, particularly what is known of their absorbability. The calcium salts most commonly used as supplements or fortificants exhibit similar absorbability when tested in pure chemical form. Choice of salt will depend mainly upon cost, compatability with the manufacturing process, and consumer acceptability. However, interaction with food, tablet, or beverage matrices can degrade intrinsic absorbability substantially. As a consequence, each product must be explicitly tested to establish the degree to which its calcium is available to consumers.