Functional gels from bovine blood proteins as fat substitutes and potential carriers of heme iron

We evaluated technological and physicochemical properties and infrared spectra of heat-induced hydrogels (HGs) and emulgels (EGs) obtained from a composite gellant (DFM) of freeze-dried bovine plasma and red cell fraction. Results showed that 10% W/W of DFM is enough to produce gels of adequate self-support, with syneresis ranging from 3 to 11% and 6–13%, for HGs and EGs, respectively. The color differences were perceptible in all cases, and the opacity related to the assembly of the networks increased with the amount of DMF in both gels. Heat-induced gelation led to heme iron (HFe) retention efficiency higher than 89.45 ± 0.19%. Also, lipid oxidation levels in the EGs were lower than the threshold value. We concluded that 10% of DMF allowed obtaining appropriate gels for their use as fat substitutes and potential heme iron vehicles in food products. However, bioavailability studies are required to better understand their behavior under digestive conditions.Industrial relevanceCurrently, a low proportion of slaughterhouse blood is aimed at human consumption. Plasma is the most widely used fraction of bovine blood, while the red cell fraction has little application for human consumption, despite its incredible nutritional value. Therefore, the results of this study represent a promising alternative for the use of the red cell fraction, which could be applied to the preparation of highly absorbed iron-enriched foods, useful in the prevention or treatment of iron-deficiency anemia. The iron-enriched gels of our study could be used as fat substitutes in the design of low-fat or improved lipid-profile food matrixes (including baked goods and meat products), which implies adding value to a by-product of slaughterhouses and a potential benefit for the industry of reformulated food products.     

畜禽血食用产品及1其研究进展

畜禽血作为畜禽屠宰加工的主要副产物之一,营养价值丰富,应用前景广阔。在传统加工利用上,畜禽血可以制作为血豆腐、血肠等食品,通过微生物发酵、酶解、微胶囊化等新兴加工技术还可开发出各种保健品、功能性食品、调味品、食品添加剂及其他风味食品,如氨基酸口服液、血红素胶囊、血酱油、肉味香精、发色剂、乳化剂、补铁强化饮料等高附加值产品,文章对利用畜禽血开发食用性产品及其研究进展做了概要综述。     

Iron fortification in dairy industry

Iron deficiency is usually the result of insufficient dietary intake of iron, poor utilization of iron from ingested food, or a combination of the two. Direct addition of iron to milk or dairy products might be an effective mean of increasing the dietary intake of iron to the general population. However, iron fortification of milk or dairy products induces several biophysicochemical modifications with important consequences. This report reviews general informations on the iron fortification of milk and dairy products.     

Impact of protein pre-treatment conditions on the iron encapsulation efficiency of whey protein cold-set gel particles

This paper investigates the possibility for iron fortification of food using protein gel particles in which iron is entrapped using cold-set gelation. The aim is to optimize the iron encapsulation efficiency of whey protein by giving the whey protein different heat treatment prior to gelation with iron. The effect of the heat treatment conditions (mild-intermediate-severe) on the iron-induced cold-set gelation process was studied to optimize the gel strength in relation to the iron concentration. Rheology was used to study the protein gel formation, and the stability of the gel particles and iron encapsulation efficiency was determined by measuring the protein and iron content at different pH. Both the iron concentration and the heat treatment conditions appear to affect the gel formation process and gel strength of the iron-induced cold-set gels. With the protein gel particles being stable at a broad pH range, the release of iron from the particles was studied as a function of time. The low release of iron at neutral pH indicated good encapsulation efficiency and capability of whey protein to keep iron bound. At low pH the release of iron increased, as is desired for bio-accessibility. In addition to differences in gel strength, the most relevant result caused by the pre-treatment of the whey protein is revealed in the amount of iron that can be entrapped per protein. It is shown that the amount of iron can be increased going from mild to severe heat treatment conditions. This suggests that the concept of using whey protein particles with iron can effectively be used to fortify food products with iron for human consumption.     

Model of nutritional iron deficiency anemia in rats

Model of alimentary iron deficiency anemia (AIDA) in rats has been created by the use of iron elimination from all diet components as much as possible. It was established that the time of AIDA development depended on iron content in diet. The model can be used for estimation of efficiency of new food products and food supplements enriched with iron.     

浅谈钙盐和铁盐的生物利用性

<正> 过去几年问,食品和饮料工业界中新产品层出不穷,配料的生产技术也不断得到改进,并推出许多营养强化食品和饮料产品。目前采用矿物质来强化食品和饮料趋势的形成,是由于可以让消费者选择的食品种类始终有限,未能满足人体各项所需,从而影响个人的健康状况,长此以往对人体的各项功     

Iron-Lactoferrin Complex Reduces Iron-Catalyzed Off-flavor Formation in Powdered Milk with Added Fish Oil

Abstract: The iron–lactoferrin complex (FeLf) is useful for dietary iron supplementation. However, the effects of FeLf on iron‐catalyzed off‐flavors in lipid‐containing food products have not been reported. In this study, we investigated the effects of FeLf on off‐flavors development during the production and storage of powdered milk with added fish oil. Powdered milk samples were formulated with FeLf or iron (II) sulfate, then stored at 37 °C for 5 mo. A sensory evaluation revealed that FeLf delayed the development of oxidized flavor and reduced metallic taste in the powdered milk compared with iron (II) sulfate. Headspace gas chromatography–mass spectrometry analysis showed that oxidized volatile compounds, such as pentanal, hexanal, heptanal, octanal, 1‐penten‐3‐one, (Z)‐4‐heptenal, (E, E)‐2,4‐heptadienal, and (E)‐2‐octenal, were less developed in the powdered milk containing FeLf than in that containing iron (II) sulfate. Iron and lactoferrin (Lf) were retained in the high‐molecular‐weight (>10000 Da) fraction of the reconstituted FeLf‐containing powdered milk after its manufacture and storage, whereas the antigenicity of Lf was lost after ultrahigh‐temperature processing at 120 °C for 5 s. These results suggest that FeLf reduces the iron‐catalyzed off‐flavors that develop during the production and storage of powdered milk. The stable iron‐holding property of FeLf contributes to the inhibition of oxidized and metallic volatile formation, although the loss of Lf antigenicity did not affect the stability of FeLf and the iron‐catalyzed formation of off‐flavors in the powdered milk. Consequently, FeLf is a suitable candidate for the simultaneous supplementation of a single food with iron and fish oil. Practical Application: The supplementation of food products with iron and fish oil is a useful approach to redressing their inadequate intake in many populations. The iron–lactoferrin complex can protect food products against the off‐flavors caused by iron‐catalyzed lipid oxidation. Our results show that the iron–lactoferrin complex is useful for the simultaneous fortification of foods and nutraceuticals with iron and fish oil because this complex also reduces the formation of iron‐catalyzed off‐flavors in powdered milk enriched with fish oil.     

The effects of heating and chemical treatment on the haem and non-haem iron content of heat-induced porcine blood curd

The effect of heating temperature (40–80°C), time (0–50 min), additions of ascorbic acid (0–5 g litre^?1) and sodium nitrite (0–200 mg litre^?1) on total, non-haem and haem iron of heat-induced porcine blood curd (a famous edible blood food in Taiwan) was investigated. The results show that non-haem iron content increased significantly (P < 0.05) when heated at above 55°C and was enhanced linearly (r = 0.96) with heating time at 80°C, while haem iron decreased relatively. In addition, a non-haem iron increase was observed in ascorbic acid, the maximum found with treatment at 4 g litre^?1. On the contrary, haem iron content increased with the presence of sodium nitrite and there was a significant change with addition above 50 mg litre^?1.     

Intracellular proteins of ethanol-treated yeast cells involved in iron sorption

Iron is essential for human health, but it sometimes causes an unpleasant taste, rusty colour and a decrease in the stability of food products. Previously, we found that ethanol-treated yeast (ETY) cells could remove iron from wine and juice, and reduce the fishy aftertaste induced by iron in wine–seafood pairings. However, the mechanism of iron sorption by ETY cells is undefined; thus, there is no indicator that can be used to estimate the iron sorption capacity of these cells. In this study, we showed that cell wall components are not mainly associated with iron sorption by investigating ETY cells with the cell wall removed. Moreover, plasma membrane permeability was correlated with the iron sorbing capacity of the cells. Microscopic analysis showed that iron accumulated within ETY cells. Proteinase-treated ETY cells had no iron sorbing capacity. On the basis of these results, we conclude that intracellular proteins are involved in iron sorption by ETY cells.     

Evaluation of the effects of specialized therapeutic canned food on the course of iron-deficiency anemia in young children

A total of 25 normal children and 131 children with iron-deficiency anemia (IDA) were investigated, 53 out of 131 IDA patients served as controls and received a standard food ration for children suffering from IDA, the rest received nutrition containing medicinal canned food. The following paraclinical parameters were evaluated in all the children investigated: red blood cell and hemoglobin content, calcium concentration, the content of ascorbic acid and vitamin B1, iron metabolism indices (serum iron, general and latent iron-binding capacity of the blood serum, coefficient of transferrin saturation with iron, serum ferritin). The results of the study have shown a favourable effect of the special-purpose medicinal canned food on IDA course in young children that necessitates their wide production and practical use.     

The use of food enriched with iron and vitamins for iron deficiency correction

The data on the usage of fortified with iron food products for iron deficiency correction are summarized. Efficiency of enrichment with different iron forms (heme, organic and inorganic salts etc.) combining with one or several vitamins and possible undesirable effect of iron excess intake are discussed.     

Influence of food processing on iron availability in vitro from extruded maize-based snack foods

Samples of an extruded maize-based snack food taken at various points during manufacture were digested in vitro under simulated physiological conditions. The proportion of iron diffusing across a semi-permeable membrane was used as an index of bioavailability. Iron diffusibility increased from less than 3 % in raw whole maize to over 20 % in the finished product. Four processing stages were found to be responsible for this enhancement: (I) refining of raw maize, (2) product formulation, (3) extrusion cooking, (4) addition of flavourings. The extrusion cooking process itself was responsible for only a small part of the increase in iron diffusibility. There was a reduction in iron content due to refining, but a small increase in iron content due to product formulation and extrusion cooking. The various factors associated with each stage of snack food manufacture are discussed in relation to their potential influence on iron availability.     

Determination of Iron Species in Samples of Iron-Fortified Food

The paper presents the determination of iron forms in food products. The procedure of sample extraction was developed and optimized, preserving the content of particular forms of iron. The colorimetric method using 2,2′-bipirydyl (measurements at 520 nm) was applied in Fe(II) determinations, while in Fe(III) determinations, the colorimetric method with potassium thiocyanate (measurements at 470 nm) was applied. The total content of iron was determined by the technique of atomic absorption spectrometry, which allowed for the determination of iron content in organic and inorganic complex compounds. Detection limits of 1 mg kg^?1 were obtained for all determined iron forms, with the precision ranging between 0.7 % and 1.5 % for 10 mg kg^?1 concentration. The optimized analytical procedure was applied in the determinations of iron forms in iron-fortified food products.     

IRON CONTENT, SENSORY EVALUATION, AND CONSUMER ACCEPTANCE OF FOOD COOKED IN IRON UTENSILS

The purpose of this study was to determine the effect of cooking food in iron utensils on the iron content, sensory quality, and consumer acceptance/ preference of the food. Hamburger patties and applesauce were cooked in iron and in glass utensils and were analyzed for iron content by atomic absorption spectrophotometry and evaluated by a trained sensory panel, by consumers, and for chroma, pH, and refractometer changes. Cooking hamburger patties and applesauce in iron utensils increased iron in the food, did not affect sensory quality or consumer acceptance/preference of hamburger patties, but affected the color and flavor and decreased consumer acceptance/preference for applesauce.     

Metal content in certain food products

The aim of the researches was the determination of the lead, cadmium, iron, copper and zinc content in selected food products available in everyday life in the city of Cracow. It was found that all food products contain lead and cadmium contaminations. The trace element content in the Polish food products was within the range of values obtained by other authors.     

Application of Liposomes in Some Dairy Products

The application of liposomes as potential carriers to deliver food components is considerably an innovative technology. While the application of liposome technology has been very limited to date, researches indicating the potential of liposomes for improving the flavor of ripened cheese using accelerated methods, the targeted delivery of functional food ingredients, the synergistic delivery of ascorbic acid and tocopherols for promoting antioxidant activity in foods, and the stabilization of minerals (such as iron) in milk have been performed. In the food industry, liposomes and nanoliposomes have been employed to encapsulate flavoring and nutritive agents, and also, they have been suitable candidates to deliver antimicrobials. In this paper, application of lipase, proteinase, nisin, and flavor-containing liposomes in products during the processing (such as cheese maturity) as well as the application of liposomes-encapsulated micronutrients (such as iron) in milk are reviewed.     

Qualitative determination of carbon black in food products

Carbon black (C.I. 77266) is an insoluble pigment produced by the partial combustion of hydrocarbons. The pigment is known by several synonyms, including vegetable carbon, lamp black and carbon ash, that correspond to the raw materials and methods used for its production. Vegetable carbon (E153) is permitted for use in colouring food in the European Union. The US Food and Drug Administration (USFDA) has not approved the use of any type of carbon black for colouring food, although the agency batch certifies the pigment as D&C Black No. 2 for use in colouring certain cosmetics. Since carbon black (as vegetable carbon) may be present in food products offered for import into the United States, the USFDA's district laboratories need a qualitative analytical method for determining its presence. We have developed an extraction method for this purpose. A sample is broken down and dissolved with nitric acid. The resulting solution is filtered and treated with hydrochloric acid to dissolve any black iron oxide also present as a colour additive. A black residue remaining on the filter paper indicates the presence of carbon black in the food. We confirmed the presence of carbon black in residues from several standards and food products using Raman spectroscopy. The limit of detection for this method is 0.0001%.     

Changes in iron,zinc and chelating agents during traditional African processing of maize: Effect of iron contamination on bioaccessibility

The effect of the different unit operations of processing traditionally used to produce four maize foods commonly consumed in Africa on the nutritional composition of the products was investigated, using Benin as a study context. The impact of the processes on lipid, fibre, phytate, iron and zinc contents varied with the process. The lowest IP₆/Fe and IP₆/Zn molar ratios, the indices used to assess Fe and Zn bioavailability were obtained in mawè, a fermented dough. Analysis of maize products highlighted a significant increase in iron content after milling, as a result of contamination by the equipment used. Evaluation of iron bioaccessibility by in vitro enzymatic digestion followed by dialysis revealed that the iron contamination, followed by lactic acid fermentation, led to a considerable increase in bioaccessible iron content. Extrinsic iron supplied to food products by the milling equipment could play a role in iron intake in developing countries.     

Modelluntersuchungen zu Bedingungen der Bildung vonN ε-Carboxymethyllysin in Lebensmitteln

In model experiments with equimolar mixtures of lysinemonohydrochloride and glucose [88% (w/v) water content, 100° C heating temperature] the influence of several conditions (hydrolysis, pH) and ingredients (iron, phosphate, and nitrite) on the formation ofN ^ε-carboxymethyllysine (CML) were evaluated. CML was analysed using a reversed-phase HPLC-method after derivatisation witho-phthaldialdehyde. CML, which is an oxidative derivative of fructoselysine, is also formed during the acid hydrolysis applied for amino acid determination in food products. In model mixtures without hydrolysis only 8–21% CML compared to that in hydrolysed samples was found. Therefore, in food products all hydrolyses for CML must be performed after borohydride reduction in order to destroy fructoselysine. This can be controlled by the determination of furosine. The pH of the model mixtures considerably influenced the formation of CML. At pH 4.0 only 70 mg, at pH 7.0 370 mg, and at pH 9.0 3170 mg CML/kg lysine were determined. The CML concentration also clearly increased with higher concentrations of iron, phosphate, and nitrite. This is explained by a promoting effect on the oxidation of fructoselysine to CML.     

含铁牛血肽改善大鼠缺铁性贫血的效果评价

为开发牛血肽相关功能性产品提供理论依据，作者研究了含铁牛血肽对于大鼠缺铁性贫血的治疗效果。以低铁鼠粮饲喂初离乳雌性SD大鼠3周，建立缺铁性贫血模型。以含铁鼠粮为正常对照，以生血宁为阳性对照，用含铁牛血肽灌胃至血红蛋白质质量浓度达到100 g/L以上。结果表明：含铁牛血肽显著地改善了缺铁性贫血引起的大鼠体质量以及白细胞、红细胞、血红蛋白和红细胞压积等血常规指标的下降，同时改善铁代谢指标血清铁和血清铁蛋白。低剂量牛血肽效果相当于生血宁，中高剂量牛血肽效果优于生血宁，证明饲喂含铁牛血肽可以改善大鼠缺铁性贫血。