Lignin Effect on Calcium Absorption in Rats

The effect of lignin on calcium absorption was studied in a rat model. Lignin preparations were isolated directly from wheat bran and from kale by two treatments, enzymatic and acidic. Calcium absorption in the presence or absence of isolated wheat bran lignin, isolated kale lignin, commercially available pine lignin, and wheat bran was determined by femur uptake of 45Ca. The fractional calcium absorption of wheat bran was significantly lower than for the control. However, there were no differences in calcium absorption between the various lignin sources and the control without lignin. Thus, lignin is probably not inhibitory to calcium absorption in plant foods.     

Absorbability of Calcium from Brassica Vegetables: Broccoli, Bok Choy, and Kale

Absorption of calcium from three intrinsically labeled Brussica sp. vegetables was measured in 15 normal women in a three-way randomized design. The test load of calcium was about 83 mg for each source. Fractional calcium absorption from broccoli averaged 0.478 ± 0.089, from bok choy stems, 0.519 ± 0.089, from bok choy leaves, 0.520 ± 0.074, and from kale 0.527 ± 0.091. These differences were both absolutely small and statistically insignificant. Mean absorbability of milk calcium ingested at the same load has been previously shown to be 0.463 ± .095. This value is slightly but significantly lower than the average value for the Brassica sources combined (0.514 ± 0.090). Thus, Brussicu vegetable sources exhibit excellent calcium bioavailability.     

Calcium Bioavailability from High Oxalate Vegetables: Chinese Vegetables, Sweet Potatoes and Rhubarb

Absorption of calcium from high calcium vegetables endogenously labeled with ⁴⁵Ca was studied in premenopausal women using a randomized cross over design. Chinese (C.) vegetables are a major source calcium, but the bioavailability is unknown and likely affected by oxalic acid content. Calcium absorption from Chinese vegetables, sweet potatoes, and rhubarb, was compared to milk at the same calcium level for calculation of an absorption index. Calcium absorption generally reflected oxalic acid content. Calcium absorption index (X±SEM) was least for C. spinach (0.257±0.0228) and rhubarb (0.235±0.0233), intermediate for sweet potatoes (0.423±0.0255), and highest for C. mustard greens (1.097±0.0532) and C. cabbage flower leaves (1.097±0.0532).     

Trypsin Inhibitor Activity and Tannin Content Do Not Affect Calcium Bioavailability of Three Commonly Consumed Legumes

Calcium bioavailability from legumes containing a range in trypsin inhibitor activity (TIA) and tannin concentration was studied. Three cultivars (Phaseolus vulgaris) were hydroponically grown and intrinsically labeled with ^4SCa. Raw and cooked legumes were fed to six groups of 6-wk old male Sprague-Dawley rats. Another group received an intraperitoneal (IP) injection of ⁴⁵Ca. An eighth group was fed a casein metal extrinsically labeled with ⁴⁵Ca. The absorption of calcium from legumes by rats averaged 47.1 ± 7.5% of IP dose. Average phytate content of the legumes was 1.7% and oxalate 0.37%. Raw legumes had an average of 15000 TIA units/g of whole bean, which were completely removed by cooking. Calcium absorption was unaffected by TIA or tannin content. Reduced availability of bean calcium was likely due to phytate and/or oxalate present in legumes.     

Distribution of 45Ca between soluble and colloidal phases of buffaloes' milk as affected by processing

The distribution of ⁴⁵Ca between the soluble and colloidal phases of skimmed buffaloes' milk, and the effects of five processing treatments, was determined by the rennet coagulation technique. The five processing treatments consisted of pasteurisation (at 71.8°C for 15 s), pre-warming (at 96°C for 5 min), sterilisation (at 121.5°C for 15 min), and cooling (for 24 h at 4–6 and 0°C). The proportion of ⁴⁵Ca in the soluble phase of raw milk was about 44% (in vitro) and 37% (in vitro), while that of original Ca was about 21% (control). In vitro, pasteurisation, pre-warming and sterilisation progressively decreased the amount of ⁴⁵Ca incorporated into the soluble phase to about 39, 31 and 27%, respectively. The decline of incorporated ⁴⁵Ca was statistically significant (P < 0.01) for the prewarming and sterilisation of milk. In vitro, the decline of incorporated ⁴⁵Ca or the transfer of ⁴⁵Ca from the soluble to the colloidal phase due to the heat treatment, was small, irregular and not significant. Changes due to cooling were not significant for any of the experiments. Significantly different results were observed for the partitioning of Ca when comparisons were made between in-vitro introduced ⁴⁵Ca and original Ca, and between in-vivo incorporated ⁴⁵Ca and original Ca.     

Absorbability of Calcium From Common Beans

Absorption of calcium from white, red, and pinto beans, labeled with ⁴⁵Ca, was measured in 24 women in a three-way randomized design using a calcium load of 72 mg and milk as the referent. Fractional absorption for the three beans averaged 0.219 ± 0.047 and did not differ by type. Milk calcium absorption at the same load was more than two times higher, 0.451 ± 0.088 (P < 0.001). Oxalate content averaged 0.34%, and phytate averaged 1.7%, a stoichiometric excess relative to calcium. To evaluate the relation of phytate to reduced absorbability, labeled pinto beans were pre-treated with phytase and fed to 10 subjects. Fractional absorption rose, averaging 0.318 ± 0.071, (P <0.01 vs. untreated beans), but was significantly below that of milk. The difference was partly accounted for by phytate, with the remainder probably due to relatively high oxalate.     

Content and in vitro availability of Fe,Zn, Mg,Ca and P in homogenized fish-based weaning foods after bone addition

The aim of the present study was to compare the Fe, Zn, Mg, Ca and P contents and their in vitro availability in five fish-based infant weaning foods, as a function of the fish bone added with the muscle. The weaning foods studied were: sole without bone (S); hake without bone (H); sole with bone and hake without bone (SBH); sole with bone (SB); and hake with bone (HB). Low levels of Fe and Zn and low percentages of these dialysed minerals were found in all the weaning foods assayed. The incorporation of bone increased the Ca and P contents, particularly in HB weaning food (92.8 ± 0.44 mg 100 g⁻¹ for Ca and 274 ± 1.93 mg 100 g⁻¹ for P). The amounts of Ca and P dialysed were also higher in the weaning foods with bone.     

Effects of shortage of calcium and other cations on 45Ca mobility,growth and nutritional disorders of tomato plants (Lycopersicon esculentum)

Calcium mobility in tomato plants grown in sand- and water-cultures with little calcium and other cations was studied using ⁴⁵Ca as a tracer. Radioautographs and ⁴⁵Ca activity measurements of plant parts showed that ⁴⁵Ca was “fixed” near the base (root or stem) of plants grown in low-Ca nutrient solutions, compared with plants grown with adequate Ca in which ⁴⁵Ca was readily translocated to the tops. When plants were grown with little Ca and other cations (i.e. low K, Mg and micronutrients), ⁴⁵Ca was also readily translocated to the tops. Calcium stress during the fruiting stage caused serious blossom-end rot of fruits, indicating that Ca absorbed by plants before fruiting was not readily available subsequently for fruit development. Leaf total-Ca is not a reliable index for predicting fruit-Ca deficiency in tomatoes.     

Constitution of leguminous seeds: VII.—Ease of cooking field peas (Pisum sativum L.) in relation to phytic acid content and calcium diffusion

Cooking tests (single pea puncture), phytic acid analyses, water absorption and ⁴⁵Ca diffusion experiments have been performed on individual peas selected from two samples of field peas (Pisum sativum L.). One sample (Avion brand) was judged by the supplier to have good cooking qualities and the other sample (3CW brand to have poor cooking qualities. The rapid rate of cooking of the interior of the pea, compared with that of the periphaeral region was not associated with a higher phytic acid content. There was no consistent difference between the distribution of ⁴⁵Ca in Avion and 3CW peas that had been soaked in water containing ⁴⁵Ca. There was a significant (1 % level) difference between the average loss of solids of Avion and 3CW peas that had been soaked at 25°. Pea plants were injected with ⁴⁵Ca ind the peas were harvested. Autoradiograms of the radioactive peas demonstrated the movement of calcium in the seed coats and in the cotyledons during cooking.     

In vitro bioavailability of calcium and iron from selected green leafy vegetables

The objective of the present investigation was to analyze the relative influence of oxalic acid, phytic acid, tannin and dietary fiber on in vitro availability of iron and calcium from green leafy vegetables (GLV). Thirteen GLV were selected and analyzed for iron, calcium, oxalic acid, phytic acid, tannin and dietary fiber contents using standard methods. The bioavailability of calcium and iron in the GLV was estimated by equilibrium dialysis. Oxalic acid content was less than 1 g kg^?1 in four greens and ranged between 1.22 to 11.98 g kg^?1 in the remaining. Dietary fiber ranged from 19.5 to 113.7 g kg^?1. Tannin content ranged between 0.6138 and 2.1159 g kg^?1 with the exception of two GLV that had 0.1332 and 14.8619 g kg^?1. Four GLV were found to have approximately 40% bioavailable iron, while the others were in the range of 6–30%. In vitro available calcium was less than or equal to 25% in eight GLV and between 34% and 52% in five GLV. Multiple regression analysis revealed that these factors together accounted for 53% (r² = 0.53) and 45% (r² = 0.45) inhibition of iron and calcium absorption, respectively. These findings infer that calcium and iron availability is influenced by the constituents present in the GLV. Copyright © 2006 Society of Chemical Industry     

Effects of psyllium and cellulose fibres on thermal,structural, and in vitro digestion behaviour of wheat starch

The study investigated the effects of adding different types of fibre (psyllium and cellulose) on in vitro digestion behaviour of wheat starch with its thermal and structural properties. Psyllium and cellulose fibres interfered with the wheat starch differently. Psyllium fibre hindered starch gelatinisation, restricted the loss of starch crystallinity, and decreased the accessibility of enzymes to starch. In contrast, cellulose fibre had no significant effect on gelatinisation and loss of crystallinity but limited the digestive enzyme mobility. The impact of psyllium was more pronounced than cellulose on reducing starch digestibility. Rapidly digestible starch fractions of the cooked starch reduced from between 57.90 ± 0.60–69.72 ± 0.46 (% in starch) to between 28.06 ± 0.36–46.34 ± 1.10 (% in starch) and 53.23 ± 0.36–66.71 ± 0.24 (% in starch) for psyllium and cellulose fibre, respectively. This information could be helpful to design foods containing starch with reduced digestibility for a healthy diet.     

The chemical composition,the nutritive value and the functional properties of malt sprout and its components (acrospires,rootlets and husks)

The components of malt sprouts were effectively separated by manual winnowing into acrospires (15·3%), rootlets (40·1%) and husks (43·7%). The bitter taste was located in the acrospires. Percent recovery of protein and fibre was, respectively, 95·2 and 87·2 of malt sprouts. The acrospires were rich in protein (30·3%) and sugars (45·7%) but low in calcium (1·94 g kg⁻¹), fibre content (4·6%) and essential amino acids. They had moderate functional properties. The rootlets were rich in calcium (19·9 g kg⁻¹) and in protein (31·9%), which had a good nutritive value (low in phytic acid and polyphenols content). They had a moderate fibre content (10·7%). Consequently, they had the highest water absorption, oil absorption and emulsification capacities. The rootlets had relatively low foam capacity but the highest foam stability. The husks were rich in fibre content (25%) but moderate in protein content (12·4%), which was rich in essential amino acids. The husks were relatively low in calcium (11·83 g kg⁻¹) and phosphorus (6·53 g kg⁻¹) contents and in vitro protein digestibility (68·9%). Their functional properties were influenced by high fibre and moderate protein contents. The first limiting amino acids were sulphur-containing ones in the malt sprouts, the acrospires and the rootlets, but it was leucine in the husks. © 1997 SCI.     

Calcium Absorption from Commonly Consumed Vegetables in Healthy Thai Women

ABSTRACT: The absorbability of calcium from ivy gourd, a green leafy vegetable (Coccinia grandix Voigt.) and winged bean young pods (Psophocarpus tetragonolobus [L] DC) were measured in 19 healthy adult women aged 20 to 45 y, in a 3‐way, randomized‐order, crossover design with an average calcium load of 100 mg and milk as the referent. The test meals were extrinsically labeled with 44Ca and given with rice as breakfast after an overnight fast. Absorption of calcium was determined on a blood sample drawn 5 h after ingestion of the test meal. Fractional calcium absorption (X± SD) was 0.391 ± 0.128 from winged beans, 0.476 ± 0.109 from ivy gourd, and 0.552 ± 0.119 from milk. The difference in fractional calcium absorption for these 2 vegetables was significant (P < 0.05) and the fractional calcium absorption from these 2 vegetables were both significantly lower than from milk. The difference was partly accounted for by the phytate, oxalate, and dietary fiber content of the vegetables. However, calcium bioavailability of these 2 vegetables, commonly consumed among Thais, was relatively good compared to milk (71% to 86% of milk) and could be generally recommended to the public as calcium sources other than milk and Brassica vegetables.     

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.     

Thermo‐physical properties of composite bread dough with maize and cassava flours

Composite wheat–cassava and wheat–maize flours were produced in ratio 100:0. 60:40, 50:50, 40:60 and 0:100 respectively. Thermo‐physical properties of bread dough were determined. For wheat –cassava composite bread dough, moisture content ranged between 44.02 ± 2.04 to 51.31 ± 2.99% dry basis (db), density (1035.2 ± 20.4 to 975.6 ± 12.6 kg m^?3), specific heat capacity (2.51 ± 0.61 to 3.01 ± 0.42 kJ kg^?1 K) and thermal conductivity (0.362 ± 0.13 to 0.473 ± 0.12 W mK^?1). While wheat–maize mixture gave 44.14 ± 1.94 to 45.09 ± 1.26%(db) of moisture content, 981.4 ± 16.3–960.4 ± 22.5 kg m^?3 density, 1.77 ± 0.17–2.61 ± 0.63 kJ kg^?1 K specific heat capacity and 0.36 ± 0.07–0.39 ± 0.02 W mK^?1 thermal conductivity. Effects of substitutions was significant on moisture content and thermal conductivity of dough while non significant influence was recorded on density and specific heat capacity at P < 0.05.     

Deoxynivalenol in wheat,maize, wheat flour and pasta: surveys in Hungary in 2008–2015

Among Fusarium mycotoxins, deoxynivalenol (DON) is the most common contaminant in case of cereals and cereal-based foods in Hungary. In this study, Hungarian wheat (n = 305), maize (n = 108), wheat flour (n = 179) and pasta (n = 226) samples were analysed (N = 818). The samples were collected during 2008–2015 in Hungary. Applied methods of analysis were enzyme-linked immunosorbent assay and liquid-chromatography coupled with a mass spectrometer. Results were compared and evaluated with Hungarian weather data. Among cereal samples, in 2011, wheat was contaminated with DON (overall average ± standard deviation was 2159 ± 2818 µg kg^?1), which was above the maximum limit (ML). In case of wheat flour and pasta, no average values above ML were found during 2008–2015, but higher DON contamination could be observed in 2011 as well (wheat flour: 537 ± 573 µg kg^?1; pasta: 511 ± 175 µg kg^?1).     

Monitoring of free glutamic acid in Malaysian processed foods,dishes and condiments

A study to quantify the free glutamic acid content of six processed foods, 44 dishes and 26 condiments available in Malaysia was performed using high-performance liquid chromatography with a fluorescence detector (HPLC-FRD). Recovery tests were carried out with spiked samples at levels from 6 to 31 mg g^?1. High recovery in different matrices was achieved ranging from 88% ± 13% to 102% ± 5.12%, with an average of 97% ± 8.92%. Results from the study revealed that the average free glutamic acid content ranged from 0.34 ± 0.20 to 4.63 ± 0.41 mg g^?1 in processed foods, while in prepared dishes it was as low as 0.24 ± 0.15 mg g^?1 in roti canai (puffed bread served with curry or dhal) to 8.16 ± 1.99 mg g^?1 in dim sum (a small casing of dough, usually filled with minced meat, seafood, and vegetables, either steamed or fried). Relatively, the content of free glutamic acid was found to be higher in condiments at 0.28 ± 0 mg g^?1 in mayonnaise to 170.90 ± 6.40 mg g^?1 in chicken stock powder.     

Production of a root‐specific flavour compound, 2‐hydroxy‐4‐methoxy benzaldehyde by normal root cultures of Decalepis hamiltonii Wight and Arn (Asclepiadaceae)

The flavour compound 2‐hydroxy‐4‐methoxy benzaldehyde from normal roots of swallow root (Decalepis hamiltonii) raised in vitro was extracted with dichloromethane, evaporated to dryness and dissolved in ethanol for qualitative (TLC) and quantitative (GC‐MS) analysis. Maximum root biomass and the maximum content of flavour compound (40 ± 2.1 µg g^?1 dry weight) were recorded after 45 days of growth on Murashige and Skoog medium containing 1.0 mg l^?1 α‐naphthaleneacetic acid. Copyright © 2004 Society of Chemical Industry     

Formulation,characterisation and sensory evaluation of Bio-Cal instant jelly fortified with chicken bone-based nano-biogenic hydroxyapatite

This study was aimed to develop Bio-Cal instant jelly enriched with nano-biogenic hydroxyapatite (HAp) that was extracted from chicken bone bio-waste. For HAp preparation, collected sample was proceeded for washing, drying, grinding, sieving, sintering (750°C) and ultra-sonication. Resultant HAp was characterised by spectroscopy techniques. The Fourier transform infrared spectroscopy (FTIR) peak of PO₄³- was visible at 1019.76 cm⁻¹ in nano-biogenic HAp that corresponds to existence of calcium salt. Particle size ranged from 100 to 800 nm, whereas calcium content was found 26.9 ± 0.09 ppm by Atomic absorption spectroscopy (AAS). Scanning electron microscopy (SEM) confirmed irregular agglomerated nano-sized crystals while X-Ray diffraction (XRD) presented crystalline behaviour at 2θ with intensity 213 a.u. The Ca/P ratio based on Laser-induced breakdown spectroscopy (LIBS) analysis was 1.82. HAp was further used to develop Bio-Cal instant jelly with four different formulations; 0%, 0.33%, 0.66% and 1%. Texture profile analysis (TPA) was done to determine cohesiveness, adhesiveness and elasticity of jelly, whereas viscosity ranged from 0.68 ± 0.01 to 0.89 ± 0.01 mm. pH of all formulations lied within the range of 5.52 ± 0.04 to 5.57 ± 0.01. The best acceptability of jelly was seen in ‘nano-biogenic HAp-A₁’ formulation with mean 7.87 ± 0.35 that may play significant role in minimising calcium risk among end-users.     

Content of strontium,lithium and calcium in selected milk products and in some marine smoked fish

The strontium, lithium and calcium contents have been determined in 87 samples of five kinds of milk‐fermented products, as well as in 93 samples of ten kinds of marine smoked fish. The samples were purchased on the local market. The representative samples were dry ashed in quartz crucibles and the ash was treated with suitable amounts of conc. HCl and a few drops of conc. HNO₃. The obtained sample solution was then used for the determination of Sr, Li and Ca by the flame atomic absorption spectrometry (AAS) method. Ca and Li were determined using the air‐acetylene flame and Sr with nitrous oxide‐acetylene flame, according to the manufacturer's recommendations. The contents of Sr in the fermented milk products ranged from 0.21 to 0.79 (mean 0.44 ± 0.07) and in the marine smoked fish from 0.02 to 4.63 (mean 1.16 ± 0.24) mg/kg of the edible form of both products. Li contents in the milk products ranged from 0.01 to 0.50 (mean 0.07 ± 0.04) and in the smoked fish from 0.00 to 0.58 (mean 0.11 ± 0.08) mg/kg. The calcium was highest in the milk products and ranged from 1 010 to 2 020.0 (mean 1 377 ± 143) mg/kg. In the smoked fish calcium varied strongly and ranged from 40 to 1 052 (mean 303 ± 53) mg/kg of the edible form. The calculated average ratio of strontium to calcium (mg Sr/1 g Ca) in the milk beverages and yogurts amounted 0.32 and in the smoked fish was 12 times as high and amounted 3.84. The main purpose of this work was to present Ca, Sr and Li together. This is justified because Sr and to some extent also Li are able to modulate Ca metabolism and vice versa.