Losses of nutrients and anti-nutrients in red and white sorghum cultivars after decorticating in optimised conditions.

The aims were to optimise pearling process of red and white sorghum by assessing the effects of pearling time and grain moisture on endosperm yield and flour ash content and to assess nutrient and anti-nutrient losses produced by pearling different cultivars in optimised conditions. Both variables significantly affected both responses. Losses of ashes (58%), proteins (9.5%), lipids (54.5%), Na (37%), Mg (48.5%) and phenolic compounds (43%) were similar among red and white hybrids. However, losses of P (30% vs. 51%), phytic acid (47% vs. 66%), Fe (22% vs. 55%), Zn (32% vs. 62%), Ca (60% vs. 66%), K (46% vs. 61%) and Cu (51% vs. 71%) were lower for red than white sorghum due to different degree of extraction and distribution of components in the grain. Optimised pearling conditions were extrapolated to other hybrids, indicating these criteria could be applied at industrial level to obtain refined flours with proper quality and good endosperm yields.

Food matrix and cooking process affect mineral bioaccessibility of enteral nutrition formulas.

BACKGROUND: When enteral formulas (EF) are administered orally as a supplement to the normal diet, they are often mixed with conventional foods or included in recipes in order to seek new flavors and textures and avoid monotony. The aims of this work were to study the bioaccessibility of Fe, Zn and Ca from commercial EF and the impact upon their incorporation into sweet preparations. Twenty commercial EF, before and after inclusion in sweet food (rice pudding, RP; banana smoothie, BS; tea, T; chocolate dessert, CD) were evaluated regarding Fe, Zn and Ca dialyzability (%DFe , %DZn , %DCa ) as an estimator of mineral bioaccessibility. RESULTS: Fe, Zn and Ca dialyzability from EF was variable and generally low. Heating during EF-sweet food preparation (T and CD) lowered values to 44.1 %DFe , possibly due to degradation of vitamin C, and 52.7 %DZn and 25.3 %DCa , due to the interaction with food components. CONCLUSION: EF and EF-sweet foods did not represent a good supply of Fe, Zn and Ca as recommended. This study demonstrated how the bioaccessibility of these minerals is affected by the food matrix in which EF is included as well as heating during food preparation.

Effects of soy protein and calcium levels on mineral bioaccessibility and protein digestibility from enteral formulas.

Enteral formulas (EF) are complex food systems which have all the nutrients in their matrix for the complete human nourishment. However, there are components in EF which can interact with minerals, reducing their absorption, and thereof the EF nutritional quality. The effect of soy protein (SP) and Ca content on Fe, Zn, and Ca bioaccessibility and protein digestibility (%DP) was assessed using a response surface design in EF. Tested SP levels were 2.5-5.0 g/100 mL of total protein. Ca levels were adjusted with Ca citrate within a range between 50 and 100 mg/100 mL. SP content negatively influenced %DP and Fe, Zn and Ca bioaccessibility. As SP content increased, mineral bioaccessibility and %DP decreased, probably due to the increased levels of phytic acid and trypsin inhibitors from SP. Ca content only affected %DCa, which had a direct relationship with Ca levels, while did not affect Fe and Zn bioaccessibility or %DP. Since Ca citrate did not impair Fe and Zn bioaccessibility, it could be an appropriate Ca source for EF fortification.

Iron, zinc and calcium dialyzability from extruded product based on whole grain amaranth (Amaranthus caudatus and Amaranthus cruentus) and amaranth/Zea mays blends.

Amaranth is a Native American grain appreciated for its high nutritional properties including high mineral content. The aim of this study was to evaluate the availability of Fe, Zn and Ca from extruded products made with two varieties of amaranth and their mixtures with maize at two levels of replacement. Mineral availability was estimated using dialyzability method. The contents of Fe (64.0-84.0 mg/kg), Ca (1977.5-2348.8 mg/kg) and Zn (30.0-32.1 mg/kg) were higher in amaranth than in maize products (6.2, 19.1, 9.7 mg/kg, respectively). Mineral availability was in the range of (2.0-3.6%), (3.3-11.1%) and (1.6-11.4%) for Fe, Ca and Zn, respectively. Extruded amaranth and amaranth/maize products provide higher amount of Fe and Ca than extruded maize. Extruded amaranth products and amaranth addition to maize could be an interesting way to increase nutritional value of extruded products.

Correction: Effects of extruded whole-grain sorghum (Sorghum bicolor (L.) Moench) based diets on calcium absorption and bone health of growing Wistar rats.

Correction for 'Effects of extruded whole-grain sorghum (Sorghum bicolor (L.) Moench) based diets on calcium absorption and bone health of growing Wistar rats' by María Gimena Galán et al., Food Funct., 2020, 11, 508-513, DOI: 10.1039/C9FO01817D.

Assessment of oxidative status and genotoxicity in photocopier operators: a pilot study.

Occupational exposure to photocopiers has been indicated as being responsible for a number of health complaints, particularly effects on the respiratory, immunological, and nervous systems. In this study, we investigated oxidative and genotoxic damage in photocopier operators by assessing catalase activity (CAT), reduced vs. oxidized glutathione ratio (GSH/GSSG), level of lipid peroxidation (TBARS), damage index by Comet assay (DICA), and buccal cells with micronuclei (BCMN). Our results reveal that the TBARS levels in operators were increased (27%; p<0.05) but that no significant alterations to GSH/GSSG or CAT activity were observed. The DICA and the number of BCMN were significantly increased (134% and 100%, respectively; p<0.05) in the exposed group. There was a significant association between the time in months spent at work and DNA damage in lymphocytes (r(s) = 0.720; p<0.001) and buccal cell with MN (r(s) = 0.538; p<0.001). Because laser printers and photocopiers have become increasingly used, it is important to control human exposure using reliable biomarkers.

Effects of extruded whole-grain sorghum (Sorghum bicolor (L.) Moench) based diets on calcium absorption and bone health of growing Wistar rats.

Apparent calcium absorption, total bone mineral content and density, and mineral contents of the right femur were studied using a growing rat model. Twenty-four male Wistar rats were fed with diets based on extruded whole grain red (RSD) or white sorghum (WSD), and control diet (CD) up to 60 days. The animals fed with sorghum diets consumed less and gained less weight compared to those fed with CD, but the efficiency of all diets was similar. Calcium intake was lower in animals fed with sorghum diets, related to the lower total intake of these animals. Apparent calcium absorption in animals fed with RSD was lower than in those fed with CD (CD: 72.7%, RSD: 51.0%, WSD: 64.8%). No significant differences in bone mineral density of total body, spin, femur, distal femur, tibia and proximal tibia were observed among the groups. However, Ca and P contents in the right femur of the rats consuming RSD were lower, indicating a certain imbalance in the metabolism of these minerals.

Refined sorghum flours precooked by extrusion enhance the integrity of the colonic mucosa barrier and promote a hepatic antioxidant environment in growing Wistar rats.

The effects of precooked-refined sorghum flour consumption on antioxidant status, lipid profile, and colonic and bone health were evaluated. Twenty-four male Wistar rats were fed with control diet (C), or red or white precooked-refined sorghum based diets (SD) for 60 days. The intake of SD was lower than that of C, but the efficiency of all diets was similar. Rats fed with SD showed lower feces excretion, cecal pH and enzyme activities (ß-glucosidase, ß-glucuronidase and mucinase) than C. White SD improved intestinal architecture, cell proliferation and apoptosis, upregulated ZO1 and occludin tight junction proteins and stimulated goblet cell differentiation, enhancing the integrity of the mucosa barrier in both proximal and distal colonic mucosa in a better way than red SD. Consumption of SD significantly decreased serum triglyceride levels compared with the C diet. The mineral content of the right femur was not different among diets. The liver enzyme activities (superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase) did not show differences among diets. Liver reducing power and reduced glutathione/oxidize glutathione ratio were higher for animals consuming SD than C. It can be concluded that the consumption of precooked refined sorghum flours still has beneficial effects for health, mainly at the colonic level, despite the lower phenolics and fibre contents of refined flours with respect to whole grain flours.

Parboiling of sorghum grains as a strategy to improve endosperm yield and mineral content of refined flours.

The aims were (i) to optimize the parboiling/decorticating process by assessing the effects of parboiling soaking temperature (60-80 ℃) and pearling time (4-6 min and 5.5-9.5 min for red and white sorghum) on endosperm yield and ash content, to obtain pregelatinized refined flours from parboiling sorghum (RF-PS) and (ii) to evaluate the final content of selected nutrients in RF-PS obtained in these optimal conditions. Endosperm yield decreased with the increase of pearling time, and a maximum around 70 ℃ soaking temperature was observed. Ash content decreased with increasing soaking temperature and pearling time. The optimal conditions of soaking temperature-pearling time were 73.3 ℃-4.8 min for red sorghum and 67.9 ℃-8.6 min for white sorghum, considering maximum endosperm yield and ash content lower than 0.65 g/100 g. In RF-PS obtained under optimal conditions, protein, lipid, Cu, and free polyphenols were higher in red sorghum than white sorghum (10.16 ± 0.62 vs. 9.42 ± 0.61 g/100 g, 0.89 ± 0.16 vs. 0.62 ± 0.11 g/100 g, 2.08 ± 0.21 vs. 1.88 ± 0.20 mg/kg, 79.51 ± 14.51 vs. 63.82 ± 4.33 mg/100 g). Fe, Zn, Ca, and Na were higher in white sorghum than red sorghum (20.61 ± 2.92 vs. 17.56 ± 0.98 mg/kg, 11.94 ± 0.84 vs. 9.58 ± 1.65 mg/kg, 87.45 ± 12.91 vs. 75.31 ± 12.57 mg/kg, 129.62 ± 9.03 vs. 102.69 ± 28.34 mg/kg). No difference was observed in the contents of ash, Mg, and K. It was possible to improve endosperm yield using a parboiling process prior to decortication. In addition, this process contributes to increase the mineral content in RF-PS.