Comparison of the Availability of Various Iron Fortificants in Bread and Milk Using an In Vitro Digestion/Caco-2 Cell Culture Method

ABSTRACT: The availabilities and dialyzabilities of various iron fortificants in bread and milk were compared using an in vitro digestion/Caco-2 cell culture model. In white bread, availability and dialyzability of electrolytic iron were lower than that of ferrous fumarate, Ferrochel®, and FeSO₄. NaFe(III)EDTA was also lower in availability than ferrous fumarate, Ferrochel®, and FeSO₄ but had the highest dialyzability. In 2% fat milk, NaFe(III)EDTA was again the highest in dialyzability but was similar in availability to ferrous fumarate, encapsulated ferrous fumarate, Ferrochel®, and FeSO₄. The results suggest that iron from NaFe(III)EDTA and electrolytic iron does not completely exchange with intrinsic iron in foods.     

Bioavailability to rats of iron from fortified grain amaranth flour

In this study, fortified and unfortified grain amaranth seed flour and FeSO₄ fortified casein diet as control were evaluated for their iron bioavailability. NaFeEDTA, ferrous fumarate, and FeSO₄-fortified grain amaranth were fed to Sprague Dawley weanling male rats. Iron intake, Hb Fe gain, Fe availability and binding capacity, serum iron, non-haem liver iron and relative biological value (RBV) were determined and values compared with FeSO₄-fortified casein control; all were improved greatly by fortification.
Relative biological values (RBV) were 0.40, 1.55, 1.75, 1.67 and 1.00 for animals receiving unfortified amaranth diet, those fed diet fortified with NaFeEDTA, ferrous fumarate, FeSO₄ and casein fortified with FeSO₄ respectively. RBV of the unfortified cereal was 40% of control suggesting perhaps low iron absorption from the amaranth cereal.
Based on the results of this study, amaranth cereal is ideal as a food vehicle for iron fortification. The iron fortificant of choice is ferrous fumarate.     

Bioavailability of Elemental Iron Powders in Bread Assessed with an In vitro Digestion/Caco-2 Cell Culture Model

ABSTRACT: Iron fortification of staple foods is arguably the most widely used strategy for increasing the iron intake of populations. Although FeSO₄ is a bioavailable form of iron, elemental iron powders are often used to fortify products with a long shelf-life, such as wheat flours, to avoid problems associated with the reactive nature of FeSO₄. Therefore, the objectives of this study were to compare the bioavailabilities of elemental iron powders manufactured with different production methods in wheat flour breads and to determine the effects of added ascorbic acid and baking, using an in vitro digestion/Caco-2 cell culture model. Two types of wheat flour (low-extraction and high-extraction) were fortified with 10 different commercial elemental iron powders and baked into breads. Iron bioavailabilities from the resulting breads, with and without added ascorbic acid, were evaluated using FeSO₄ as the control. Depending on the type of wheat flour, bioavailabilities of several powders were comparable to FeSO₄, but there was no consistent trend as to which production method produced the most bioavailable powder. In general, ascorbic acid enhanced, whereas the baking process reduced iron bioavailability from bread. Our results suggest that some elemental iron powders are potential alternatives to FeSO₄. Human studies are warranted before any of these powders are selected for national fortification programs.     

Sensory Trial to Assess the Acceptability of Zinc Fortificants Added to Iron-fortified Wheat Products

ABSTRACT: We studied the sensory acceptability of products made from iron- and zinc-fortified wheat flour. Subjects tasted bread and noodles fortified with 30 mg of iron as FeSO₄/kg flour or iron and either 60 or 100 mg of zinc/ kg flour as either ZnSO₄ or ZnO. Subjects rated their degree of liking (DOL) for flavor, texture, and overall acceptability, using a 9-point hedonic scale. All products were generally well liked, although noodles fortified with iron and ZnO had slightly lower DOL scores than noodles fortified with iron only or iron and ZnSO₄. We conclude that foods prepared from zinc-fortified wheat flour should be well accepted.     

Optimization of the fermentation medium for alpha-galactosidase production from Aspergillus foetidus ZU-G1 using response surface methodology

ABSTRACT:  The optimization of fermentation medium for alpha-galactosidase production by Aspergillus foetidus ZU-G1 was investigated in shaker flask fermentation. A one-factor-at-a-time experiment was used to screen the preferable nutriment (carbon sources, nitrogen sources, and essential elements) for alpha-galactosidase production. A fractional factorial design was used to screen the main 5 factors, soybean meal, wheat bran, KH₂PO₄, FeSO₄·7H₂O, and the medium initial pH, that affected the production of alpha-galactosidase. The central composite experimental design was further adopted to derive a statistical model for optimizing the composition of the fermentation medium. The experimental results showed that the optimum fermentation medium for alpha-galactosidase production by Aspergillus foetidus ZU-G1 was composed of 3.2% soybean meal (w/v), 2% wheat bran (w/v), 0.1% KH₂PO₄ (w/v), and 0.05% FeSO₄·7H₂O (w/v); initial medium pH was 6.31. The results further predicted that alpha-galactosidase activity reached 64.75 U/mL after 96-h incubation in this medium, which was approximately 7 times higher than that incubated in the nonoptimized medium. The time course of alpha-galactosidase production in the optimized medium composition was also carried out to validate the model.     

EFFECTS OF LOW CONCENTRATIONS OF H2O2 ON LIPID OXIDATION AND OF STORAGE AND pH ON NONHEME IRON CONTENT OF RAW BEEF MUSCLE

Ground beef samples were prepared from semimembranosus muscles, and beef muscle residue devoid of heme pigments was prepared by repeated washing of the ground muscle with distilled-deionized water. When ground muscle, or muscle residue samples treated with metmyoglobin-H₂O₂ (4 mg metmyoglobin/g muscle residue; 1:0.1 to 1:1 for molar ratio of metmyoglobin to H₂O²) were stored at 4°C for 0 or 6 days, no changes in nonheme iron content were observed. Similarly, nonheme iron content of stored samples was not affected by pH (5.5, 6.0 or 6.5). While metmyoglobin-H₂O² added to water-extracted beef muscle residue catalyzed the oxidation of the indigenous lipids, treatment of the residue with H₂O² alone had no effect on the oxidation.     

EXTRACTION OF VICTORIA AND RED GLOBE GRAPE SEED OILS USING SUPERCRITICAL CARBON DIOXIDE WITH AND WITHOUT ETHANOL

SFE of the oils of two varieties of grape seeds (Victoria and Red Globe) was performed in a flow apparatus at 40C and 250 bar. The effect of the solvent on the extraction yield was studied using CO₂ and CO₂ modified with ethanol, and the yield of extraction was compared with conventional extraction methods (Bligh and Dyer and Soxhlet using hexane). SC CO₂  +  ethanol extracted higher lipid amounts from both varieties, compared with SC CO₂ extraction. The comparison between SFE and conventional extraction methods showed that the highest extraction yield was obtained with SC CO₂  +  ethanol (10%, w/w) (14.7 and 11.8% for Red Globe and Victoria grape seeds, respectively), while pure SC CO₂ afforded the lowest lipid yields. The fatty acid compositions of the oils obtained by SFE were analyzed. Fractions containing higher proportions of PUFAs were obtained at lower solvent/dry grape seed ratios, while fractions richer in SFAs and MUFAs were obtained at higher solvent/dry grape seed ratios.

PRACTICAL APPLICATIONS

SFE could fractionate grape seed oil and afford various grades of oil containing different proportions of fatty acids. The highest grape seed lipid yield obtained was with SC CO₂ + ethanol, making this solvent a promising and powerful one for grape seed oil extraction, showing a great advantage compared with conventional extraction methods.     

Fe3O4@ZrO2磁纳米粒子在酪蛋白磷酸肽富集中的应用

本实验将制备好的Fe₃O₄@ZrO₂磁性纳米粒子作为载体,对经胰蛋白酶消化后的酪蛋白磷酸肽（Casein Phosphopeptides,CPP）进行高效地选择性富集。实验以CPP的N/P（摩尔比）以及磁纳米粒子吸附量为评价指标,进行单因素实验以便选取较优的实验因素,分析酪蛋白水解度、吸附pH、吸附时间、吸附温度及肽溶液初始浓度这五个因素对Fe₃O₄@ZrO₂磁性纳米粒子选择性吸附CPP的能力的影响,优化CPP富集的技术参数。结果表明,磁性材料最佳富集工艺系数为:酪蛋白的水解度为22%,反应pH=4.5,吸附温度为30 ℃,吸附时间为50 min,肽溶液初始浓度为50 mg/mL;在此条件下,可得到N/P（摩尔比）为4.87的CPP,磁纳米粒子的吸附量为94.37 mg/g,且用NaOH(pH13)溶液进行解析,CPP的洗脱率可达95%以上。综上,Fe₃O₄@ZrO₂磁性纳米粒子呈现出优异的选择性富集CPP的潜力,对高质量高纯度CPP 的生产具有重要的指导意义。     

Shelf life of Turkish whey cheese (Lor) under modified atmosphere packaging

In this study, the shelf life of Lor cheese stored under different atmosphere compositions was assessed and compared. Lor cheeses were held in four different atmospheres containing: vacuum packaging (VP), 40% CO₂/60% N₂, 60% CO₂/40% N₂ and 70% CO₂/30% N₂ (modified atmosphere packaging). Control cheeses were stored in air. All cheese samples were kept in the refrigerator at 4°C for 45 days and investigated for physicochemical, microbiological and sensory properties. The acidity index value was significantly higher ( P  < 0.05) in the control and vacuum packaged samples than in those stored for the same period under CO₂. Microbiological results showed that modified atmosphere packaging delayed microbial growth compared with air and VP samples. Of the three modified atmospheres, gas mixtures 60% and 70% CO₂ were the most effective for inhibition of growth of micro-organisms. Sensory evaluation (odour and taste) results showed that Lor cheese packaged under modified atmosphere packaging (60% CO₂/40% N₂ and 70% CO₂/30% N₂ ) retained good characteristics for 45 days of storage, while vacuum and control samples were sensorily unacceptable after 10 days of storage.     

Effect of different extraction and precipitation methods on yield and quality of pectin

An experimental study has been conducted to determine the combined effects of different extraction conditions and precipitation method on the yield and quality of high methoxyl pectin from lemon peels. Pectin was extracted using different mineral acids (HCl, HNO₃ and H₂SO₄) at four concentration levels (0.025; 0.05; 0.1 and 0.2  m ), at 70 °C for 4 h. The soluble pectin was precipitated by iso-propanol or by an aluminium sulphate, Al₂(SO₄)₃, solution at pH 4. The extraction with HCl and HNO₃, at the highest concentrations investigated, followed by aluminium precipitation led to the best results in terms of yield (22–25%), quality and gelling power of pectin with a remarkable decrease of alcohol consumption as compared to the alcoholic precipitation under the same extracting conditions.     

Relative Bioavailability of Dietary Iron from Three Processed Soy Products

The relative bioavailability of iron from soy flour (SF), freeze-dried soy beverage (SB) and soy concentrate (SC) was determined utilizing a hemoglobin repletion bioassay. Weanling male rats were fed a low iron depletion diet (3.5 ppm Fe) for 4 wk. For the next 2 wk groups of rats were fed repletion diets containing 0, 6, 12, or 18 ppm added iron from ferrous sulfate, SF, SB, or SC. Slope ratio analysis revealed that the relative iron bioavailabilities from SC (92%) and SF (81%) were not different from the reference standard, ferrous sulfate added to a casein-based diet, whereas that from SB (66%) was significantly less (P<0.01) than the inorganic source of iron. Analysis of results at individual iron levels suggested an iron bioavailability of SC>SF>SB.     

Zinc and iron bioavailability of genetically modified soybeans in rats

ABSTRACT:  The aim of this work was to evaluate zinc and iron bioavailability of UFV-116, a new variety without 2 lipoxygenases, with better taste and flavor than a commercial variety OCEPAR 19, containing all 3 isozymes. To evaluate zinc absorption using ⁶⁵Zn whole body retention and femur ⁶⁵Zn uptake, rats were given 3 g of a ⁶⁵ZnCl₂ labeled test meal (0.25 μCi). The 2 varieties were tested at the level of 9 and 30 ppm of zinc as defatted soy flour. Two other groups (control) received egg white as source of protein and ZnS0₄.H₂0 as the zinc source. To evaluate iron absorption, using ⁵⁹Fe whole body retention, animals were given a 3 g ⁵⁹FeCl₃ labeled test meal (0.2 μCi). The 2 varieties were tested at 12 and 25 ppm iron as defatted soy flour. Whole fat soy flour of variety 1 (UFV-116) was higher ( P < 0.05) in Ca, K, Mg, phytic acid, and oxalate than variety 2 (OCEPAR-19). No difference was observed among the soybean varieties ( P > 0.05) for femur ⁶⁵Zn retention, at different levels of zinc. However, whole body retention was lower ( P < 0.05) for UFV-116 than for OCEPAR-19. Femur ⁶⁵Zn uptake was correlated with the whole body retention; however, whole body retention was more sensitive. Whole body ⁵⁹Fe retention from UFV-116 was lower ( P < 0.05) than from OCEPAR-19. Zinc and iron bioavailability was lower for UFV-116, possibly due to its higher content of antinutrient factors, especially phytate.     

RHEOLOGICAL BEHAVIOUR OF SHEARED JAMS. RELATION WITH FRUIT CONTENT

Eight samples of jam were sheared to destroy gel structure and their flow behaviour was analysed in a concentric cylinder viscometer. Jams were prepared from 4 different fruits—strawberry, peach, plum, and apricot—at 50% and 30% fruit content approximately. Flow of sheared jam showed time dependence, which could be quantified by the Weltmann model and which was eliminated by shearing samples for 8 min at 300 rpm. Casson's yield stress values were obtained at two ranges of shear rates: 0.08–1.01 s⁻¹ (O₀₁) and 2.58–387.30 s⁻¹ (o₀₂). o₀₂ values were about double the o₀₁ values. Flow was adequately described by the Herschel and Bulkley model, introducing either of the yield stress values (o₀₁ or o₀₂). Significant differences were found for some of the rheological parameters studied (Weltmann A and B constants, o₀₁, o₀₂, K₁, and n₁) between samples containing 50% and 30% fruit. These results demonstrate the role played by fruit particles in the rheological behaviour of this type of product and suggest the possibility of using rheological parameters as indices of fruit content in jams.     

INFLUENCE OF MODIFIED ATMOSPHERE PACKAGING ON GROWTH OF CLOSTRIDIUM PERFRINGENS IN COOKED TURKEY

Clostridium perfringens containing samples of sterile ground turkey were studied to assess growth under modified atmosphere conditions. Samples were packaged under various atmospheres (CO₂/O₂/N₂: 75/5/20, 75/10/15, 75/20/5, 25/20/55, 50/20/30), stored at 4, 15 and 28C, and sampled periodically for growth. Diluted samples were plated on Shahidi Ferguson perfringens agar (Difco Laboratories, Detroit, MI) to determine vegetative cell counts. Temperature abuse (cyclic and static) of the turkey product was also investigated. The results showed that the growth of C. perfringens was slowest under 25–50% CO₂/20% O₂/balance N₂ at 15 and 28C. There was no growth at 4C for up to 28 days. Temperature abuse (28C storage) of refrigerated products for 8 h did not permit C. perfringens growth. Use of 25–50% CO₂/20% O₂/balance N₂ may extend the shelf-life of turkey, but in the absence of proper refrigeration, it cannot be relied upon to eliminate the risk of C. perfringens food poisoning .     

Protein Solubility, Water Retention, and Fat Binding of Corn Germ Protein Flour Compared with Milk Proteins

Protein solubility (PS), water retention (WR), and fat binding (FB) of corn germ protein flour (CGPF), nonfat dry milk (NFDM), whey protein concentrate (WPC), and sodium caseinate (SC) were comparatively studied using response surface methodology. PS and WR of all samples were affected by pH except for WR of CGPF. PS and WR of all samples were not affected by incubation temperature except of WR of CGPF. Incubation temperature influenced FB of CGPF and WPC but not of NFDM and SC. Sample concentration significantly affected FB of all samples. CGPF was an effective protein source in terms of WR and FB. For FB, SC > CGPF = NFDM > WPC and for PS, WPC=NFDM=SC > CGPF.     

The Effect of Brine Ingredients on Carrot Texture during Thermal Processing in Relation to Pectin Depolymerization due to the β-Elimination Reaction

ABSTRACT:  Thermal texture degradation of carrots was studied at a temperature of 100 °C in aqueous solutions containing sodium chloride, citric acid, ascorbic acid, and ethylenediaminetetraacetic acid (EDTA) at different concentrations. To enhance the texture of the final product, the carrot samples were pretreated at 65 °C for 30 min in an aqueous calcium chloride solution (5 g/L). For all case studies considered, the pH of the solutions was adjusted to pH = 6.0. In parallel, both the changes in degree of esterification (DE) and the progress of the β-elimination reaction of carrot pectin under the same conditions were investigated. The kinetic parameters for texture degradation (rate constant k_t and final texture value [TP_∞/TP₀]) were estimated using a fractional conversion model. The results indicate that both the rate constant for texture degradation ( k_t ) and the rate constant for the β-elimination reaction ( k_b ) increased with increasing additive concentration, while the final texture values (TP_∞/TP₀) and DE decreased with increasing additive concentration in all systems studied. A high correlation was observed between the relative rate constant for texture degradation and the relative rate constant for the β-elimination reaction on the one hand, and the relative final texture value and the relative rate constant for the β-elimination reaction on the other hand, suggesting that the influence of the solutes on texture degradation can be explained by their influence on the β-elimination reaction.     

Mineral and water soluble vitamin content in the Kombucha drink

Summary Biologically active substances (water soluble vitamins and minerals) were analyzed in 'Kombucha'—a curative liquor, produced by the so-called 'Kombucha cultivation' (Macedonian collection of microorganisms, No 734) in sweet black tea decoct. The water soluble vitamins in the Kombucha drink were separated and identified using thin layer chromatography (TLC) and quantified by the comparison of their chromatographic UV spectra with the reference compounds. Four soluble vitamins have been determinated to have the following concentrations: vitamin B₁ 0.74 mg ml⁻¹, vitamin B₆ 0.52 mg ml⁻¹, vitamin B₁₂ 0.84 mg ml⁻¹ and vitamin C 1.51 mg ml⁻¹. Mineral elements of nutritional and toxicological importance were determined in dissolved ash using atomic absorption chromatography (AAS). Mineral composition content involved determination of the essential elements: zinc, copper, iron, manganese, nickel and cobalt. Investigations of some toxic elements showed that lead and chromium were present in very small amounts, whereas cadmium was not found.     

RHEOLOGICAL INDICES OF FRUIT CONTENT IN JAMS: EFFECT OF FORMULATION ON FLOW PLASTICITY OF SHEARED STRAWBERRY AND PEACH JAMS

The effect of formulation factors on Casson yield values measured at low shear rates (0.08 ≤γ≤ 1.01s^-1) (σ₀₁) and at medium shear rates (2.58 ≤γ≤ 387.30s^-1) (σ₀₂) was analyzed in previously sheared strawberry and peach jams. Twenty three samples of each fruit jam were prepared according to a second order composite rotatable design. Composition ranges were: fruit content, 25–55%; soluble solids content, 60–70° Brix; added pectin in strawberry jams, 0.3–0.7% and in peach jams, 0.1–0.5%. Variation of σ₀₁ values in strawberry jams depended mainly on the interactions between fruit and soluble solids and between fruit and pectin, while in peach jams, it depended on fruit-soluble solids and soluble solids-pectin interactions. Patterns of change of σ₀₂ values with composition were similar to those observed for σ₀₁ in both strawberry and peach jams. Predictive power of σ₀₁ and σ₀₂ values for estimation of fruit content was low, but taken in conjunction with soluble solids content and total pectin values, 79.5% of the variability of fruit content in strawberry jams and 91.1% of same in peach jams could be explained.     

Quality Changes of Deepwater Pink Shrimp (Parapenaeus longirostris) Packed in Modified Atmosphere

ABSTRACT: The storage of deepwater pink shrimp ( Parapenaeus longirostris ) in modified atmosphere was studied. Two gas mixtures were tested (40% CO₂/30% O₂/30% N₂ and 45% CO₂/5% O₂/50% N₂), combined with sulfites-based pretreatment, in comparison with air storage. The quality of shrimp was evaluated by sensory (black spot presence) and chemical analyses (pH value and nucleotides breakdown products). Generally, both atmospheres preserved the shrimp quality up to 9 d compared with 4 to 7 d of ice storage (only with pretreatment), although it seems that atmosphere containing 45% CO₂/5% O₂/50% N₂ was the most effective.     

The effect of ascorbic acid on oxidative browning of white wines and model wines

The effects of ascorbic acid addition to white wines and model wines were either anti-oxidative or pro-oxidative, and depended, inter alia , on the duration of storage. Soon after its addition, ascorbic acid decreased the redox potential and brown colour of model wines and white wines. However, with time, these effects were reversed, and redox potential, SO₂ consumption and browning were greater in samples with added ascorbic acid. The point at which the net effect of ascorbic acid addition was to increase browning occurred earlier at higher SO₂ levels. Under a variety of accelerated (45®), or prolonged (ranging from three months to five years) storage conditions, the browning of model wines and white wines was invariably enhanced by ascorbic acid addition, and this enhancement took place whether or not SO₂ was present. The addition of SO₂ alone, rather than ascorbic acid alone or SO₂ plus ascorbic acid, appears to be the most effective and least expensive way of protecting white wine from browning during bottle conservation.