Effect of Heat Treatment on Bioavailability of Meat and Hemoglobin Iron Fed to Anemic Rats

Efficiency of converting dietary iron from meat, bovine hemoglobin (HB) and ferrous sulfate into hemoglobin was investigated in anemic rats. Raw or autoclaved HB, and raw, autoclaved, boiled, or baked beef round, and ferrous sulfate were mixed into diets to give 36 mg Fe/kg diet. Heat treatments increased the efficiency of converting both HB and meat iron into hemoglobin by the anemic rats. Efficiencies of conversion were 23, 30, 33, 37, 37, 36 or 60 (LSD 0.05/0.01 = 4/6), respectively, for raw HB, autoclaved HB, raw meat, autoclaved meat, boiled meat, baked meat or ferrous sulfate. An in vitro measurement of iron availability in meat correlated poorly with bioavailability determined in rats. Cooking did not significantly affect the bioavailability of meat iron.     

Preparation,characterization, bioavailability in vitro and in vivo of tea polysaccharides–iron complex

The task of this study was to prepare a complex of tea polysaccharides (TPS) with ferric iron and research its bioavailability in vitro and in vivo. Optimum condition for preparing tea polysaccharides–iron complex (TPIC) was as follows: TPS and FeCl₃ with a weight ratio of 1:2.4, reacted in a water bath at 60 °C for 3 h, generating an iron content for TPIC of 14.60 %. The digestion in vitro experiment showed that availability of TPIC was sufficient. Then, iron bioavailability in vivo of TPIC was evaluated by the rat hemoglobin-repletion bioassay with ferrous sulfate (FeSO₄) as the positive control. Results indicated that at the end of 21 days’ iron regeneration phase, the values of hemoglobin (Hb) concentration, free erythrocyte protoporphyrin (FEP), serum iron (SI) concentration, and mean cell hemoglobin (MCHC) of rats supplemented with FeSO₄ and TPIC increased quickly to those of normal ones. If the bioavailability of FeSO₄ was given 100 % with Hb concentration, SI concentration and MCHC as the evaluation index, respectively, bioavailability of TPIC were in the range of 101.85–116 %. These results demonstrate that TPIC is a good iron supplement source for increasing uptake and bioavailability in the body.     

Bioavailability of Iron Produced by the Corrosion of Steel in Apples

The bioavailability of iron formed by the corrosion of low-carbon steel (99% Fe) in contact with Red Delicious apples was measured in a rat model using a depletion-repletion experiment. The percentage of ingested iron converted to hemoglobin iron (Conversion Efficiency) was 74, 57, and 56%, respectively, for daily doses of 110, 190, and 285 μg of this iron. (Conversion Efficiency for FeSO₄ was 46-50%). When compared with FeSO₄= 100, the relative biological value of this iron was found to range from 93–153. Ingestion of one Red Delicious apple that has been exposed to eight large iron nails for 24 hr could provide 10–15 mg iron having good bioavailability.     

Meat fats in nutrition

This article reviews the fat content and fatty acid composition of meats in the human diet and discusses nutritional facts related to meat, meat products and other meat-containing foods as sources of dietary fats. Meat is an increasingly important source of high-value animal protein worldwide. Meat fat comprises mostly monounsaturated and saturated fatty acids, with oleic (C18:1), palmitic (C16:0), and stearic acid (C18:0) being the most ubiquitous. Meat and meat products are considerable sources of cholesterol in the diet. In most industrialized countries, a high meat intake contributes to a higher than recommended total and saturated fat and cholesterol intake. Another concern is that meat may replace sources of other important nutrients in the diet. Therefore, the advice to consumers is to prefer lean meats and low-fat meat products and use meat in moderation only.     

Effects of Meat and Selected Food Components on the Valence of Nonheme Iron during In Vitro Digestion

Our objective was to determine whether meat and other dietary factors have the capacity to reduce nonheme ferric iron to the ferrous form during digestion. Beef, selected organic acids, selected purified proteins, red blood cells, whole blood, or blood plasma was mixed with FeCl₃ and subjected to simulated gastrointestinal digestion. Ferrozine was used to monitor the formation of dialyzable Fe(II). Ascorbic acid, glutathione and cysteine produced large increases in Fe(II) while meat (raw and cooked), hemoglobin and red blood cells yielded smaller increases. Casein, plasma, bovine serum albumin and egg albumin did not affect Fe(II) formation. Our Results suggest dietary factors which enhance iron absorption in vivo promote Fe(III) reduction in the intestinal lumen.     

Bioavailability of Iron in Fermented Soybeans

Hemoglobin depletion-repletion assay was used for determining iron bioavailability. The relative biological value (RBV) of iron in boiled nonfermented soybeans was the lowest among the products evaluated. The RBV of iron increased from 60.1% in boiled nonfermented soybeans to 86.7% by lactic acid producing microorganisms and to 87.5% by Rhizopus oligosporus fermentation (FeSO₄= 100%). Results of this research suggested that fermentation by lactic acid producing organisms and Rhizopus oligosporus increased the RBV of iron.     

Color, Pigment and Iron Content of Meat Loaves with Blood, Blood Emulsion, or Mechanically Deboned Meat Added

The hemoglobin, myoglobin, and iron content in slaughter-house blood, a blood emulsion, mechanically deboned meat (MDM) and meat minces with these raw materials added, were determined. Blood and blood emulsion were added in the range 0-5%. MDM was added as a substitute for ground beef. The pigment and iron content in the minces were compared with the surface color of heated meat loaves produced. Minces containing blood yielded lighter meat loaves upon heating (i.e. a higher lightness L* was observed) than did minces containing blood emulsion or MDM, even if the amounts of extractable hemoglobin and myoglobin in the minces were equal. At equal concentrations of iron, minces with blood and MDM gave lighter meat loaves than did minces to which blood emulsion had been added.     

Effect of irradiation of frozen meat/fat trimmings on microbiological and physicochemical quality attributes of dry fermented sausages

Lipid oxidation is a major factor in meat quality. In order to relate human perceptions of lipid oxidation, as determined by a trained taste panel, to a chemical measurement of oxidation, we studied meat from animals with a wide range of potential oxidation through differences in their PUFA composition and by displaying the meat in high oxygen modified atmosphere packs for varying lengths of time. Meat was obtained from 73 Angus- and Charolais-cross steers from different trials that had been raised on 10 different diets: grass silage (high in C18:3, n-3), cereal concentrate (high in C18:2, n-6), three diets with 3% added fat consisting of three levels of protected lipid supplement (high in C18:2, n-6 and C18:3, n-3, ratio 1:1), a control with Megalac^® (relatively saturated), three diets with three levels of inclusion of protected fish oil (high in C20:5 n-3 and C22:6 n-3) plus a constant amount of unprotected fish oil and a final diet with an unprotected fish oil control. The longissimus dorsi muscle was excised from the left carcass side, aged vacuum packaged for 10–13 days depending on the projects and frozen for less than eight months. TBARS and sensory analyses were performed on steaks displayed for 0, 4 or 9 days under simulated retail conditions, exposed to light in modified atmosphere packaging (CO₂:O₂; 25:75). Meat oxidation increased throughout display for each of the diets, as shown by a rise in TBARS values. This increase was not linear, differences between 0 and 4 days of display were smaller than between 4 and 9 days of display. The lowest TBARS and lowest increment occurred in the two control diets and the grass-fed animals, probably due to the more saturated fat of meat from animals fed the control diets and the higher content of vitamin E. Sensory attributes were also influenced by time of display. Positive attributes, such as beef flavour or overall liking, decreased throughout display, whereas negative attributes, such as abnormal and rancid flavours, increased.     

Protective effects of a synthetic soybean isoflavone against oxidative damage in chick skeletal muscle cells

The antioxidant and protective properties of a synthetic soybean isoflavone (SI) were investigated using chick skeletal (leg) muscle cells (SMC) isolated from 20-day-old Linnan yellow broiler chick embryo. Skeletal muscle cells were cultured in Dulbecco’s modified Eagle’s medium treated with 0, 12.5, 25, 50, 75 and 100 μM SI, respectively, under 80 μM H₂O₂/FeSO₄ conditions. After 24 h of incubation, SI reduced the loss of SMC under oxidative stress by H₂O₂/FeSO₄. The addition of SI significantly promoted SMC proliferation (P < 0.01). Upon treatment with 25, 50, 75 and 100 μM SI, the activity of total superoxide dismutase in the supernatant of the media was enhanced by 17.0%, 13.0%, 13.3% and 11.9%, respectively (P < 0.05). Compared to the control, the activity of glutathione peroxidase was significantly increased only at 25 μM concentration of SI (P < 0.05), and the increment was 90.7%. The activity of catalase was increased by 49.2% and 49.1%, respectively, at 75 and 100 μM SI (P < 0.01). The concentration of creatine kinase in the media was decreased by 61.6% and 60.6%, respectively, at 75 and 100 μM SI (P < 0.01). The addition of SI did not affect the activity of lactate dehydrogenase in the media. In conclusion, the SI protected skeletal muscle cells from oxidative damage, attributed to its antioxidant activity.     

Effects of dietary rosemary extract on lamb spoilage under retail display conditions

A dietary rosemary extract (RE) was tested to extend the shelf life of raw lamb meat. Lambs were supplemented with 0.6 mg kg⁻¹ RE during fattening (from 13 to 25 kg live weight). Meat spoilage (total viable counts, psycrophilic bacteria, Enterobacteriaceae, molds and yeasts), TBARS, CIE L*a*b* color and the sensory traits of lamb cuts were analyzed on days 0, 7, 14 or 21 under retail display conditions (70/30 O₂/CO₂ atmosphere, 2 °C temperature and 1600 lx lighting). Supplementation of the lamb diet with RE was effective (P < 0.05) in prolonging the time chilled-packed lamb cuts could be kept under retail display conditions. Dietary rosemary clearly inhibited lipid oxidation and rancidity, and was moderately efficient in preventing sensory deterioration and microbial spoilage. Although the results concerning meat preservation were limited, the dietary use of rosemary extracts in lambs seems to be promising as a nutritional strategy for improving meat quality.     

Possible role of volatile amines as quality-indicating metabolites in modified atmosphere-packaged chicken fillets: Correlation with microbiological and sensory attributes

The present work evaluated the possible role of volatile amines as indicator(s) of poultry meat spoilage. Fresh chicken meat (breast fillet) was packaged in four different atmospheres: air (A), vacuum (VP) and two modified atmospheres (MAs), namely M1, 30%/65%/5% (CO₂/N₂/O₂) and M2, 65%/30%/5% (CO₂/N₂/O₂). All chicken samples were kept under refrigeration (4 ± 0.5 °C) for a period of 15 days. Of the four treatments, the VP and M1 and M2 gas mixtures were the most effective for delaying the development of aerobic spoilage microbial flora. Pseudomonas spp. in chicken samples stored under M2 gas mixture and VP were significantly lower than all the other samples after 15 days of storage. Of the remaining bacterial species examined, lactic acid bacteria (LAB), Brochothrix thermosphacta, were dominant in the microbial association of both aerobically- and MA-packaged chicken, while yeasts contributed to a much lesser extent in the final microbial flora of chicken meat. On the basis of microbiological data (TVC), shelf-life extensions of 2, 4 and 9–10 days were achieved by VP and M1 and M2 gas mixtures. Results of the present work showed that the limit of sensory acceptability (a score of 6) was reached for the aerobically, vacuum-packaged and M1 gas mixture chicken samples approximately on days 6–7 and 9–10, respectively. Based on sensory (taste) analysis and with regard to chicken spoilage and freshness, TMA-N and TVB-N limit values of acceptability, namely 10.0 mg N/100 g and 40 mg N/100 g for chicken samples stored in air, may be proposed as the upper limit values for spoilage initiation of fresh chicken meat stored aerobically. Interestingly, the M2 gas mixture sample did not reach these limit values throughout the 15 day storage period. The formation of volatile amines during chill storage of chicken meat, under the packaging conditions examined in the present study, seemed to be in good agreement with the increase in microbiological count (TVC) and sensory taste score except for the M2 gas mixture.     

In vitro iron absorption of α-lactalbumin hydrolysate-iron and β-lactoglobulin hydrolysate-iron complexes

To study the feasibility of promoting iron absorption by peptides derived from α-lactalbumin and β-lactoglobulin, the present work examined the transport of iron across Caco-2 monolayer cell as in vitro model. Caco-2 cells were seeded in bicameral chambers with α-lactalbumin hydrolysate-Fe (α-LAH-Fe) complex and β-lactoglobulin hydrolysate-Fe (β-LGH-Fe) complex, α-LAH and iron mixture, β-LGH and iron mixture, FeSO₄ and ascorbic acid mixture, and FeSO₄. In addition, the cytotoxicity of α-LAH-Fe and β-LGH-Fe complexes were measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The iron absorption and ferritin content were assessed using the coupled in vitro digestion/Caco-2 cell model. Results support that peptide-iron complexes can promote ferritin formation and it is possible to apply β-LGH-Fe complexes as iron-fortified supplements with high iron absorbability.     

Extrusion and iron bioavailability in chickpea (Cicer arietinum L.)

The effect of extrusion cooking (14% moisture and 130°C processing temperature) and of home-cooking on chickpea iron bioavailability was studied by the hemoglobin regeneration method in anemic rats. The iron pool was calculated from hemoglobin concentration and animal weight, and iron bioavailability from the relationship between iron pool gain (Δ pool) and mg of ingested iron. Iron bioavailability relative to ferrous sulfate was calculated by the following equation: Y=63.989 e^−0.0458X [Y= % absorbed; X=ingested Fe (mg)] on the basis of the results of control groups. The results showed that there was no significant difference between groups (extruded and cooked) in terms of mean percentage of iron bioavailability relative to Fe₂SO₄. We conclude that chickpea is a good source of iron and extrusion cooking is a process comparable to home-cooking in terms of iron bioavailability.     

Effect of Crystalline Structure on Oxidation of Fish Oil in Stearin:Fish Oil Mixtures

Effects of incorporation of stearin fraction into fish oil on crystallisation behaviour and oxidative stability of fish oil were examined. The stearin fraction (S₂₅) was obtained from step-wise dry fractionation of anhydrous milk fat at 25 °C. Analysis of fatty acid composition by gas chromatography showed that unsaturated fatty acids (89.3 %) were enriched in the fish oil whereas the S₂₅ typically comprises of saturated fatty acids (79.4 %). A series of S₂₅:fish oil mixtures (0:100, 25:75, 50:50, 75:25; 90:10 and 100:0) was prepared by mixing the S₂₅ and fish oil at 50 °C under flushing of nitrogen gas. Crystallisation and thermal properties and crystal structures of the mixtures were investigated by differential scanning calorimetry and small- and wide-angle X-ray scattering, respectively. The crystallisation/melting temperatures and crystallisation/melting enthalpies of the mixtures increased with increasing ratios of S₂₅ blended into fish oil. All mixtures showed similar crystal structures (double- and triple-chain length) and crystal polymorphs (α, β’ and β) at 4 °C. A decrease in S₂₅ fraction in the mixtures caused a higher proportion of triple-chain length crystal packing and β polymorph. Measurement of peroxide values of the mixtures upon storage at 8 °C for 42 days showed that blending as low as 25 % S₂₅ sufficiently delayed the lipid oxidation of fish oil by about two-fold and the rancidity threshold to 16 days instead of 9 days for fish oil only. This study demonstrates that mobility of oxygen and triacylglycerol (TAG) molecules in fish oil can be restricted by crystalline state of milk fat, in turn, limiting the propagation of oxidative reaction in fish oil.     

Palatability and Texture of Ground Meat Patties Made with Varying Amounts of Pork and Turkey

Meat mixtures were prepared containing pork lean and turkey lean in ratios of 0/100, 33/67, 100/0 and a constant fat content. Blends were prepared with and without a commercial seasoning-antioxidant mixture (SA) and evaluated after 0, 3, 6 or 9 days (4°C) storage or 0, 14 or 28 days (-20°C) storage. Flavor intensity scores for blends containing up to 67% turkey were not different (P > 0.05); however, 100% turkey patties had lower flavor intensity scores. Off-flavor and firmness scores were not affected by blend for products containing between 33% and 100% pork lean, while storage had no effect on off-flavor in products containing SA. Juiciness was not affected by blend or storage. Results indicate acceptable patties can be made from blends of pork and turkey containing relatively high levels of turkey.     

Meat Production and Consumption: Environmental Consequences

Meat production is projected to double by 2020 due to increased, per capita global consumption of meat and population growth. The livestock sector is one of the most significant contributors to urgent environmental problems. In Europe, food consumption is responsible for approximately 30% of total greenhouse gas (GHG) emissions. Meat generally has a considerably higher carbon footprint than plant-based food. This is especially true for beef, due to the emissions of methane (CH₄) from enteric fermentation in ruminants.     

Iron bioavailability from Amaranthus species: 2—Evaluation using haemoglobin repletion in anaemic rats

Initial screening of 46 lines from 12 species of Amaranthus indicated wide variation in total iron (Fe) and small but significant differences in bioavailable Fe when estimated by an in vitro assay. To verify if differences in bioavailable Fe detected by in vitro assay were biologically significant, one line from each species A tricolor, A hypochondriacus and A cruentus was evaluated using a haemoglobin (Hb) repletion assay with anaemic rats. Anaemic rats were fed treatment diets in which almost all Fe was provided by amaranth lines, and Hb gains were compared to those of rats fed control FeSO₄ diets. Slope ratio analysis indicated that Fe supplied by A hypochondriacus had a greater relative bioavailability (61%) than from A tricolor (44%), when compared to FeSO₄ (100%). However, A tricolor contained a higher concentration of total Fe (690 ppm) in the leaf material. When the same amount of amaranth was added to individual diets (30 g kg⁻¹ diet), analysis of Hb repletion efficiency (HRE) indicated that A tricolor supported the largest Hb gain of the three lines, despite having the lowest relative bioavailability compared to A hypochondriacus and A cruentus. Despite a lack of correlation between total and bioavailable Fe, these results suggest future efforts should focus initially on enhancing total Fe concentration of green leafy vegetables (GLVs), until the forms of bioavailable Fe in these plant materials are identified. Rat bioassay did confirm relative differences in bioavailable Fe estimated by the in vitro assay, supporting use of the in vitro assay in breeding programmes focused on improving Fe nutritional quality of GLVs. © 1998 Society of Chemical Industry     

Effect of Feeding Three Levels of Riboflavin, Niacin and Vitamin B6 to Male Chickens on the Nutrient Composition of Broiler Breast Meat

Sixty day-old male chicks were fed three rations differing in riboflavin (R), vitamin B₆, and niacin (N) content. The three rations were: (1) an adjusted basal ration containing R, B₆ and N 10% above National. Research Council recommendations, (2) a ration containing 75% of the 3 vitamins as in (1), and (3) with 125% of the 3 vitamins as in (1). Birds were grown for 51 days and the breast meat harvested and analyzed for proximate composition, 3 vitamins and 9 minerals. No significant differences in the nutrient content of meat were found attributable to the dietary treatments. Results indicated that broiler meat composition was fairly constant even though birds consumed wide differences in R, B₆ and N.     

Effect of elevated accumulation of iron in ferritin on the antioxidants content in soybean sprouts

Cultivation of soybean sprouts in abiotic stress conditions, resulted from the presence of 5–25?mM FeSO₄ in the culture media, causes a strong overexpression of ferritin. Accumulation of ferritin iron in sprouted seeds germinated in the 20?mM solution of FeSO₄ was 67 times higher than in sprouts germinated in distilled water. The cultivation conditions also influence on another antioxidant content—mainly β-carotene content, which increased 28 times (in sprouts cultured in 10?mM FeSO₄ solution) in comparison to the content in dry seeds. Obtained in stress conditions sprouted seeds contain less tocochromanoles than raw seeds. However, their total tocochromanol content was higher than in sprouted seeds cultured in distilled water in every examined concentration of Fe²⁺. A total antioxidant activity is increased only during culturing in 0–10?mM media, and it is positively correlated to the total phenolic compounds content (r?=?0.8498). We concluded that germination in high abiotic stress also causes the increase in different antioxidants content, not only in ferritin, which is directly involved in the process of iron detoxification.     

Influence of An Addition of Textured Milk Proteins Upon Physicochemical Properties of Meat Mixtures

Meat systems consisted of beef haunch (pH 5.63) in which textured milk proteins were substituted at: 0, 10, 20, 30, 40, 50, 75, and 100%. The effects of these substitutes on the physicochemical properties of ground meats were measured for products containing no salt, sodium chloride (2%), polyphosphate mixture Hamine (0.5%) and sodium chloride and Hamine together (2%+ 0.5%). Measurements included: water absorption capacity, water-holding capacity, thermal shrinkage, consistency, viscosity, fat absorption capacity, emulsifying capacity, emulsion stability, and active acidity. Addition of textured milk proteins improved the technological adaptability of ground beef, optimum substitution depending on the type of salt. In order to improve the physicochemical properties of beef, substitution of 30% meat by textured milk proteins with addition of 2% sodium chloride, is recommended.