Functional sheep milk powder and preparation method thereof
By adding iron fortifiers and functional factors to sheep milk, functional sheep milk powder is prepared, which solves the problems of low bioavailability of iron fortifiers and fat oxidation, and achieves efficient utilization of iron and long-term preservation of milk powder.
Patent Information
- Application Number
- CN202311701113.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-12
- Publication Date
- 2025-11-28
- Estimated Expiration
- 2043-12-12
AI Technical Summary
In the existing technology, iron fortifiers have low bioavailability in sheep milk and promote fat oxidation, resulting in waste of iron nutrients and poor storage of milk powder.
Functional sheep milk powder is prepared by adding iron fortifiers and functional factors, such as ferrous gluconate, sodium iron EDTA, prebiotics, and vitamin C, to sheep milk, followed by homogenization, concentration, and spray drying. This process improves iron bioavailability and reduces fat oxidation.
It improves the utilization of iron fortifiers in sheep milk, slows down the increase of fatty acid value and TBA value, promotes the absorption of ferrous iron, and is suitable for long-term storage.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of milk powder processing, in particular to a functional sheep milk powder and a preparation method thereof. BACKGROUND
[0002] Iron is a trace element necessary for maintaining normal physiological functions of the human body, and is also the most common nutrient deficiency in the world population. When the body's iron content is insufficient, it may lead to iron deficiency anemia, metabolic disorders of electron transfer and oxidation-reduction. Using food as a carrier is a common way to supplement iron, that is, eating iron-fortified food. Commercially available iron-fortified foods include salt, soy sauce, cereal products and dairy products, etc.
[0003] The iron content in sheep milk is about 0.8mg / kg. Although the addition of iron nutritional fortifier to sheep milk increases the iron content, the bioavailability of the iron nutritional fortifier in sheep milk does not correspondingly increase, resulting in the loss and waste of iron nutritional elements. At the same time, iron promotes the oxidation of fat in sheep milk powder, which is not conducive to the storage and preservation of the milk powder.
[0004] Therefore, how to improve the utilization of iron nutritional fortifier in sheep milk and reduce the oxidation of iron nutritional fortifier to fat in sheep milk powder is a problem that needs to be solved by those skilled in the art. SUMMARY
[0005] The purpose of the present application is to provide a functional sheep milk powder and a preparation method thereof to solve the problems existing in the prior art and to efficiently improve the bioavailability of iron nutritional fortifier in sheep milk.
[0006] To achieve the above purpose, the present application provides the following solutions:
[0007] One of the technical solutions of the present application provides a preparation method of a functional sheep milk powder, comprising the following steps:
[0008] After sterilizing the sheep milk, iron nutritional fortifier and functional factors are added and uniformly mixed, and the concentrated milk with a solid content of 45%-52% is prepared by concentration.
[0009] The concentrated milk is spray-dried to obtain the functional sheep milk powder.
[0010] Further, the sheep milk includes fresh sheep milk or reconstituted sheep milk.
[0011] Preferably, the preparation steps of the reconstituted sheep milk are as follows: mixing sheep milk powder and water to obtain a milk emulsion with a concentration of 18%(w / w), which is the reconstituted sheep milk.
[0012] Further, the functional factors include at least one of functional oil, prebiotics and Vc.
[0013] Preferably, the functional oil includes tea seed oil or tomato seed oil, and the addition amount is 3-7.5 g / L.
[0014] Preferably, the prebiotic includes fructo-oligosaccharide or galacto-oligosaccharide, and the addition amount is 3-6 g / L.
[0015] Preferably, the addition amount of Vc is 100-125 mg / L.
[0016] After the prebiotic is fermented by intestinal microorganisms, short-chain fatty acids can be produced to promote the proliferation of intestinal mucosa, and the intestinal pH value can be adjusted to promote the conversion of ferric iron into divalent iron which is more beneficial to the human body, and at the same time, the carbohydrates can be chelated with iron to form a complex, the complex has small molecular weight, good water solubility and stability in an acidic environment, and can pass through the biological membrane to promote the absorption of iron in the gastrointestinal tract of the human body.
[0017] Vc can promote the reduction of ferric iron to divalent iron, and can form a chelate with iron under the low pH condition of the stomach, and can be maintained in the intestinal tract to prevent the interaction of iron with other ligands (such as phytate and other iron absorption inhibitors), thereby increasing the solubility and absorption rate of iron.
[0018] Further, the iron nutritional fortifier includes ferric sodium ethylenediaminetetraacetate or ferrous gluconate, and the addition amount is 10-17.5 mg / L.
[0019] Further, the method further comprises a step of defatting the sheep milk, and the fat content of the defatted sheep milk is ≤0.03 g / 100 mL.
[0020] Preferably, the defatting step comprises: centrifuging the sheep milk at 2-6 ℃ and at 4000-5000 rpm for 10-20 min, filtering through four layers of gauze, and repeating the operation at least twice to complete the defatting of the sheep milk.
[0021] Further, the homogenization is performed at 6000-7000 rpm for 1 min.
[0022] Further, the concentration is performed in a rotary evaporator under the conditions of a rotation speed of 50-60 rpm, a water bath temperature of 50-60 ℃, and a vacuum degree of 0.09 Mpa.
[0023] Further, the spray drying is performed under the conditions of an inlet temperature of 160-180 ℃, an outlet temperature of 80-100 ℃, a feeding speed of 0.8 L / h, a fan of 90%, and a compressor air pressure of 0.3 Mpa.
[0024] The second technical scheme of the present application provides a functional sheep milk powder prepared by the above method.
[0025] The present application discloses the following technical effects:
[0026] Iron nutritional fortifier promotes the oxidative decomposition of fat in sheep milk powder, and the addition of functional factors can effectively delay the increase of fatty acid value and TBA value of iron-fortified sheep milk powder, delay the oxidation of fat, and be more conducive to long-term storage.
[0027] The functional sheep milk powder prepared in the application improves the utilization of iron nutritional fortifier in sheep milk, not only improves the content of absorbable divalent iron, but also improves the proportion of absorbable divalent iron in absorbable iron. BRIEF DESCRIPTION OF DRAWINGS
[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.
[0029] Figure 1 The standard curve of 12 iron nutritional fortifiers in the iron ion concentration range of 0mg / L-12mg / L (a) and 0mg / L-60mg / L (b);
[0030] Figure 2 The dialyzable divalent iron content (a), dialyzable total iron content (b), undialyzable divalent iron content (c), total divalent iron content (d) and ratio of dialyzable divalent iron to dialyzable total iron (e) of 12 iron nutritional fortifiers fortified sheep milk;
[0031] Figure 3 The dialyzable divalent iron content (a), dialyzable total iron content (b), undialyzable divalent iron content (c), total divalent iron content (d) and ratio of dialyzable divalent iron to dialyzable total iron (e) of the functional sheep milk powder prepared in Examples 1-2 and Comparative Examples 1-4;
[0032] Figure 4 The dialyzable divalent iron content (a), dialyzable total iron content (b), undialyzable divalent iron content (c), total divalent iron content (d) and ratio of dialyzable divalent iron to dialyzable total iron (e) of the functional sheep milk powder prepared in Examples 3-4 and Comparative Examples 5-8;
[0033] Figure 5 The dialyzable divalent iron content (a), dialyzable total iron content (b), undialyzable divalent iron content (c), total divalent iron content (d) and ratio of dialyzable divalent iron to dialyzable total iron (e) of the functional sheep milk powder prepared in Examples 5-6 and Comparative Examples 1, 3, 9-10;
[0034] Figure 6Dialyzable divalent iron content (a), dialyzable total iron content (b), undialyzable divalent iron content (c), total divalent iron content (d), and the ratio of dialyzable divalent iron to dialyzable total iron (e) of the functional sheep milk powders prepared for Examples 7-8 and Comparative Examples 5, 7, 11-12;
[0035] Figure 7 Acid value of the functional sheep milk powders prepared for Examples 22-25 (SGTF, SETG, SSGTF, SSETG), Comparative Example 1 (SFG), Comparative Example 3 (SSG), Comparative Example 5 (SE), and Comparative Example 7 (SSE) stored for 6 months;
[0036] Figure 8 TBA value of the functional sheep milk powders prepared for Examples 22-25 (SGTF, SETG, SSGTF, SSETG), Comparative Example 1 (SFG), Comparative Example 3 (SSG), Comparative Example 5 (SE), and Comparative Example 7 (SSE) stored for 6 months. DETAILED DESCRIPTION
[0037] Various exemplary embodiments of the present application will now be described in detail, with reference to the figures. The detailed description is merely illustrative of certain aspects of the application, and does not limit the scope of the application. Rather, the scope of the application is limited only by the claims.
[0038] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. In addition, any numerical values recited herein include all values from the lower to the upper bound of the range, inclusive of the lower and upper bounds. Any numerical value, however, can be expressed as approximately or approximately. Ranges of values and / or amounts are approximations, and are only to the present application. The moduli of these smaller ranges are independently combinable with one another to fall within the scope of the ranges.
[0039] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, the preferred methods and materials are described. All documents mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In case of conflict, the content of the present specification will control.
[0040] Various modifications and changes can be made to the specific embodiments of the present application described herein without departing from the scope or spirit of the application. Other embodiments of the application will be apparent to those of ordinary skill in the art from the description and examples presented herein. The description and examples are illustrative of certain embodiments of the application and are not intended to limit the scope of the application.
[0041] As used herein, "comprise", "comprising", "having", "including", "contain", "containing", "include" and the like are open-ended terms that are intended to mean including but not limited to.
[0042] The sheep milk used in the examples and the comparative examples of the present application is fresh sheep milk or reconstituted sheep milk. During the research process, the influence of replacing fresh sheep milk with reconstituted sheep milk on the test data is minimal. Therefore, the sheep milk used in the examples and the comparative examples of the present application is fresh sheep milk or reconstituted sheep milk, and the two can be replaced equally. The preparation method of the reconstituted sheep milk is as follows: mixing sheep milk powder and water to form a milk emulsion with a concentration of 18% (w / w) to obtain the reconstituted sheep milk. The fresh sheep milk and the reconstituted sheep milk are referred to as whole sheep milk.
[0043] The preparation steps of the defatted sheep milk are as follows: centrifuging fresh sheep milk or reconstituted sheep milk at 2-6°C at 5000 rpm for 20 min, filtering through four layers of gauze, and repeating the operation at least twice to complete the defatting of the sheep milk, which is referred to as defatted sheep milk.
[0044] The concentration in the examples and the comparative examples of the present application is carried out in a rotary evaporator under the conditions of a rotation speed of 50 rpm, a water bath temperature of 60°C, and a vacuum degree of 0.09 Mpa.
[0045] The homogenization in the examples and the comparative examples of the present application is carried out under the condition of 6000 rpm for 1 min.
[0046] The spray drying process parameters in the examples and the comparative examples of the present application are as follows: an inlet temperature of 170±1°C, an outlet temperature of 80-90°C, a feeding speed of 0.8 L / h, a fan of 90%, and a compressor air pressure of 0.3 Mpa.
[0047] The preparation steps of the formula milk powder in the examples and the comparative examples of the present application include:
[0048] After sterilizing the whole sheep milk or the defatted sheep milk, the iron nutritional fortifier and the functional factor are added according to the proportions in Table 1. After homogenization and uniform mixing, the concentrated milk with a solid content of 45%-52% is prepared by concentration. Then, the formula milk powder is obtained by spray drying the concentrated milk.
[0049] The functional factor includes at least one of functional oil, prebiotic, and Vc.
[0050] Example 1
[0051] Preparation of the functional sheep milk powder:
[0052] Ferrous gluconate and prebiotics (fructooligosaccharides or galactooligosaccharides) are added to the whole sheep milk.
[0053] Example 2
[0054] Preparation of functional sheep milk powder:
[0055] Ferrous gluconate and prebiotics (fructooligosaccharides or galactooligosaccharides) were added to skimmed sheep milk.
[0056] Example 3
[0057] Preparation of functional sheep milk powder:
[0058] Ferrous sodium ethylenediaminetetraacetate and prebiotics (fructooligosaccharides or galactooligosaccharides) were added to whole sheep milk.
[0059] Example 4
[0060] Preparation of functional sheep milk powder:
[0061] Ferrous sodium ethylenediaminetetraacetate and prebiotics (fructooligosaccharides or galactooligosaccharides) were added to skimmed sheep milk.
[0062] Example 5
[0063] Preparation of functional sheep milk powder:
[0064] Ferrous gluconate and functional oil (tea seed oil or tomato seed oil) were added to whole sheep milk.
[0065] Example 6
[0066] Preparation of functional sheep milk powder:
[0067] Ferrous gluconate and functional oil (tea seed oil or tomato seed oil) were added to skimmed sheep milk.
[0068] Example 7
[0069] Preparation of functional sheep milk powder:
[0070] Ferrous sodium ethylenediaminetetraacetate and functional oil (tea seed oil or tomato seed oil) were added to whole sheep milk.
[0071] Example 8
[0072] Preparation of functional sheep milk powder:
[0073] Ferrous sodium ethylenediaminetetraacetate and functional oil (tea seed oil or tomato seed oil) were added to skimmed sheep milk.
[0074] Examples 9-13
[0075] Preparation of functional sheep milk powder:
[0076] Ferrous gluconate, functional oil (tomato seed oil) and prebiotics (fructooligosaccharides) were added to whole sheep milk.
[0077] Examples 14-17
[0078] Preparation of functional sheep milk powder:
[0079] Ferrous sodium ethylenediaminetetraacetate, functional oil (tea seed oil) and prebiotic (galactooligosaccharide) were added to whole sheep milk.
[0080] Example 18
[0081] Preparation of functional sheep milk powder:
[0082] Ferrous gluconate and Vc were added to whole sheep milk.
[0083] Example 19
[0084] Preparation of functional sheep milk powder:
[0085] Ferrous gluconate and Vc were added to skim sheep milk.
[0086] Example 20
[0087] Preparation of functional sheep milk powder:
[0088] Ferrous sodium ethylenediaminetetraacetate and Vc were added to whole sheep milk.
[0089] Example 21
[0090] Preparation of functional sheep milk powder:
[0091] Ferrous sodium ethylenediaminetetraacetate and Vc were added to skim sheep milk.
[0092] Example 22
[0093] Preparation of functional sheep milk powder:
[0094] Ferrous gluconate, functional oil (tomato seed oil), prebiotic (fructooligosaccharide) and Vc were added to whole sheep milk. Denoted as SGTF.
[0095] Example 23
[0096] Preparation of functional sheep milk powder:
[0097] Ferrous sodium ethylenediaminetetraacetate, functional oil (tea seed oil), prebiotic (galactooligosaccharide) and Vc were added to whole sheep milk. Denoted as SETG.
[0098] Example 24
[0099] Preparation of functional sheep milk powder:
[0100] Ferrous gluconate, functional oil (tomato seed oil), prebiotic (fructooligosaccharide) and Vc were added to skim sheep milk. Denoted as SSGTF.
[0101] Example 25
[0102] Preparation of functional sheep milk powder:
[0103] Ferrous sodium ethylenediaminetetraacetate, functional oil (tea seed oil), prebiotic (galactooligosaccharide) and Vc were added to skimmed sheep milk. Denoted as SSETG.
[0104] Comparative Example 1
[0105] Preparation of sheep formula milk powder:
[0106] Ferrous gluconate was added to whole sheep milk. Denoted as SFG.
[0107] Comparative Example 2
[0108] Preparation of sheep formula milk powder:
[0109] Ferrous gluconate and prebiotic (isomalto-oligosaccharide, xylo-oligosaccharide or stachyose) were added to whole sheep milk.
[0110] Comparative Example 3
[0111] Preparation of sheep formula milk powder:
[0112] Ferrous gluconate was added to skimmed sheep milk. Denoted as SSG.
[0113] Comparative Example 4
[0114] Preparation of sheep formula milk powder:
[0115] Ferrous gluconate and prebiotic (isomalto-oligosaccharide, xylo-oligosaccharide or stachyose) were added to skimmed sheep milk.
[0116] Comparative Example 5
[0117] Preparation of sheep formula milk powder:
[0118] Ferrous sodium ethylenediaminetetraacetate was added to whole sheep milk. Denoted as SE.
[0119] Comparative Example 6
[0120] Preparation of sheep formula milk powder:
[0121] Ferrous sodium ethylenediaminetetraacetate and prebiotic (isomalto-oligosaccharide, xylo-oligosaccharide or stachyose) were added to whole sheep milk.
[0122] Comparative Example 7
[0123] Preparation of sheep formula milk powder:
[0124] Ferrous sodium ethylenediaminetetraacetate was added to skimmed sheep milk. Denoted as SSE.
[0125] Comparative Example 8
[0126] Preparation of sheep formula milk powder:
[0127] Ferrous sodium ethylenediaminetetraacetate and prebiotics (isomalto-oligosaccharides, xylo-oligosaccharides or stachyose) were added to skim sheep milk.
[0128] Comparative Example 9
[0129] Preparation of sheep formula milk powder:
[0130] Ferrous gluconate and functional oils (milk thistle seed oil, sacha inchi oil, peony seed oil or Acer truncatum seed oil) were added to whole sheep milk.
[0131] Comparative Example 10
[0132] Preparation of sheep formula milk powder:
[0133] Ferrous gluconate and functional oils (milk thistle seed oil, sacha inchi oil, peony seed oil or Acer truncatum seed oil) were added to skim sheep milk.
[0134] Comparative Example 11
[0135] Preparation of sheep formula milk powder:
[0136] Ferrous sodium ethylenediaminetetraacetate and functional oils (milk thistle seed oil, sacha inchi oil, peony seed oil or Acer truncatum seed oil) were added to whole sheep milk.
[0137] Comparative Example 12
[0138] Preparation of sheep formula milk powder:
[0139] Ferrous sodium ethylenediaminetetraacetate and functional oils (milk thistle seed oil, sacha inchi oil, peony seed oil or Acer truncatum seed oil) were added to skim sheep milk.
[0140] The amounts of iron nutrient fortifiers and functional factors in Examples 1 to 25 and Comparative Examples 1 to 12 are shown in Table 1.
[0141] Table 1
[0142]
[0143]
[0144]
[0145] Test Example 1
[0146] Preparation of simulated gastrointestinal fluid and other reagents:
[0147] Simulated gastric juice: 4.0 g pepsin was dissolved in 50 mL 0.01 mol / L HCl and then diluted to 100 mL with 0.1 mol / L HCl.
[0148] Simulated intestinal juice: 0.5 g trypsin and 3.0 g sodium taurocholate were dissolved in 125 mL 0.01 mol / L NaHCO3 and then diluted to 250 mL with 0.1 mol / L NaHCO3.
[0149] PIPES buffer solution: PIPES was dissolved in deionized water to 0.15 mol / L, and then adjusted to pH 6.3 with 1 mol / L HCl.
[0150] HEPES buffer solution: HEPES was dissolved in deionized water to 0.3 mol / L, and then adjusted to pH 9.9 with 1 mol / L NaOH.
[0151] Protein precipitation and iron reduction solution: 100 g trichloroacetic acid and 50 g hydroxylamine hydrochloride were dissolved in a small amount of deionized water, then 100 mL of 1 mol / L HCl solution was added, and finally deionized water was added to 1 L.
[0152] Protein precipitation solution: The preparation method was the same as that of the protein precipitation and iron reduction solution, but hydroxylamine hydrochloride was not added.
[0153] Ferrous color developing agent: 0.25 g o-phenanthroline was dissolved in 0.1 mol / L HCl solution, diluted to 100 mL, and stored in the dark.
[0154] Determination of dialyzable divalent iron content and the ratio of dialyzable divalent iron to total dialyzable iron:
[0155] The prepared functional sheep milk powder was prepared into 18% (w / w) reconstituted sheep milk, 20 mL of reconstituted sheep milk was taken into a test tube and 1 mL of simulated gastric juice was added, and shaken in a 37°C water bath for 2 hours. A dialysis bag containing 20 mL of PIPES buffer was placed in each test tube, and shaken in a constant temperature water bath for 30 minutes. Then the pH of the solution in the test tube was adjusted to 7.0 with 1 mol / L NaHCO3, 5 mL of simulated intestinal juice was added, and the shaking was continued in a 37°C water bath for 2 hours. The dialysis bag was taken out and rinsed with deionized water. The iron in the dialysis bag was considered to be dialyzable iron, and the iron remaining outside the dialysis bag was considered to be undialyzable iron. The dialyzable divalent iron, total dialyzable iron, and undialyzable divalent iron were determined, and the total divalent iron content was calculated.
[0156] 2.0 mL of dialysate in the dialysis bag was taken, and 1.0 mL of protein precipitation solution was added. The measured iron was dialyzable divalent iron (DFe(II)).
[0157] Take dialysis bag inside dialysate 2.0 mL, add 1.0 mL protein precipitation and iron reduction solution, dialysis bag inside Fe 3+ is reduced to Fe 2+ 2+ Commonly considered as dialyzable total iron (D).
[0158] Take dialysis bag outside solution 2.0 mL add protein precipitation solution 1.0 mL, measured by colorimetric analysis of iron is not dialysis divalent iron (NDFe (II)).
[0159] Dialyzable divalent iron DFe (II) + not dialysis divalent iron NDFe (II) is the total divalent iron content. Through the dialyzable divalent iron and dialyzable total iron content, the ratio of dialyzable divalent iron to dialyzable total iron (DFe (II) / D, %) is calculated.
[0160] The standard curve of 12 iron nutritional fortifiers in the iron ion concentration of 0 mg / L ~ 12 mg / L (a) and 0 mg / L ~ 60 mg / L (b) two mass concentration range is shown in Figure 1 . In two different mass concentration range, the linear correlation of iron ion concentration and absorbance is good, the linear correlation coefficient R 2 all reached 0.997 or more, the highest reached 0.9995, so the standard curve of Figure 1 iron ion concentration calculation accuracy is higher.
[0161] Among them, 12 kinds of iron nutritional fortifiers are glycine ferrous, fumarate ferrous, pyrophosphate ferrous, pyrophosphate iron, sodium iron EDTA, ferrous lactate, ferrous sulfate, ferrous chloride, ferrous gluconate, ferrous citrate, ferric chloride, ferric ammonium citrate.
[0162] 12 kinds of iron nutritional fortifiers are added to whole fat sheep milk and skim sheep milk respectively at an addition amount of 12.5 mg / L, mixed thoroughly, then in vitro simulated gastrointestinal digestion test is carried out, DFe (II), D, NDFe (II) of the sample is measured, DFe (II) + NDFe (II), DFe (II) / D of the sample is calculated, the results are shown in Figure 2 .
[0163] Dialyzable divalent iron represents the iron agent that can be dialyzed and exists in the form of divalent iron in in vitro digestion test, the higher the value, the better the iron agent utilization and the better the dialysis ability, as Figure 2 (a) shows that the dialyzable divalent iron content of different iron fortified sheep milk has certain difference, indicating that after most iron nutritional fortifiers are added to sheep milk, the difference of iron absorption is large, and the iron utilization ability of most whole fat iron fortified sheep milk is higher than that of skim, which shows that whole fat milk is more conducive to iron fortification. The higher the dialyzable total iron value of the iron agent, the better the total dialysis ability in in vitro test, as Figure 2 (b) It can be seen that the dialyzable total iron content of different iron-fortified whole sheep milk and skim sheep milk after simulated digestion is different. The undialyzed divalent iron represents the divalent iron remaining after not passing through the dialysis membrane, which still exists in the form of divalent iron, and the higher the value, the better the ability to reduce or maintain the form of divalent iron. According to Figure 2 (c) It can be found that the dialyzable total iron content in sheep milk fortified with different iron nutritional fortifiers is not the same. The total divalent iron is the sum of dialyzable divalent iron and undialyzed divalent iron, which represents the total number of divalent iron with better availability, and the higher the value, the better the ability of sheep milk to reduce or maintain the form of divalent iron, as shown in Figure 2 (d) It can be seen that the range of total divalent iron of different iron-fortified whole sheep milk and skim sheep milk after simulated digestion has differences. The ratio of dialyzable divalent iron to dialyzable total iron represents the concentration of divalent iron in dialyzed iron, and the higher the value, the more stable the divalent iron form under the condition of high dialysis ability, and the value closer to 100% represents the better availability of iron, Figure 2 (e) It can be seen that the ratio of dialyzable divalent iron to dialyzable total iron in sheep milk fortified with different iron nutritional fortifiers is also not the same. DFe(II) and DFe(II) / D are the main reference indexes for the selection of iron nutritional fortifiers, and NDFe(II) and DFe(II)+NDFe(II) are the secondary reference indexes for the selection of iron fortifiers. The DFe(II) / D ratio is not better when it is closer to 100%. The ratio of iron-fortified whole sheep milk with ethylenediaminetetraacetic acid iron is 52.8%, but the dialyzable divalent iron content is 1.97 mg / kg, which shows that the ratio of dialyzable divalent iron to dialyzable total iron of the milk fortified with this iron nutritional fortifier is not high, but the divalent iron content in the total dialyzed iron is high, which is more easily absorbed and utilized by the human body. It can be seen from the analysis that, in combination Figure 2 (a)- Figure 3 (e) It can be seen that the ratio of dialyzable divalent iron to dialyzable total iron in sheep milk fortified with different iron nutritional fortifiers is also not the same. DFe(II) and DFe(II) / D are the main reference indexes for the selection of iron nutritional fortifiers, and NDFe(II) and DFe(II)+NDFe(II) are the secondary reference indexes for the selection of iron fortifiers. The DFe(II) / D ratio is not better when it is closer to 100%. The ratio of iron-fortified whole sheep milk with ethylenediaminetetraacetic acid iron is 52.8%, but the dialyzable divalent iron content is 1.97 mg / kg, which shows that the ratio of dialyzable divalent iron to dialyzable total iron of the milk fortified with this iron nutritional fortifier is not high, but the divalent iron content in the total dialyzed iron is high, which is more easily absorbed and utilized by the human body. It can be seen from the analysis that, in combination
[0164] Table 2 is the dialyzable divalent iron (DFe(II)) and the ratio of dialyzable divalent iron to dialyzable total iron (DFe(II) / D, %) of the functional sheep milk powder prepared in Examples 9-21.
[0165] Table 2
[0166]
[0167] Figure 3 Table 2 is the dialyzable divalent iron (DFe(II)) and the ratio of dialyzable divalent iron to dialyzable total iron (DFe(II) / D, %) of the functional sheep milk powder prepared in Examples 9-21. Figure 3In (a), the prebiotic species had a significant effect on the absorption of ferrous gluconate in sheep milk, and the results varied with the prebiotic. Fructo-oligosaccharides and isomalto-oligosaccharides had similar effects on the absorption of divalent iron in whole sheep milk, at 2.97 mg / L and 3.05 mg / L, respectively, while the addition of xylo-oligosaccharides and stachyose inhibited the absorption of divalent iron in whole sheep milk. The five different prebiotics promoted the absorption of divalent iron in skim sheep milk, with isomalto-oligosaccharides being the most effective, at 3.36 mg / L. Figure 3 In (b), for dialyzable total iron, the addition of galacto-oligosaccharides, fructo-oligosaccharides and isomalto-oligosaccharides to whole sheep milk did not significantly change the dialyzable total iron content, but the dialyzable divalent iron content increased, indicating that the functional factors promoted the reduction of trivalent iron to divalent iron, although they did not increase the absorption of iron. For skim sheep milk, isomalto-oligosaccharides (4.37 mg / L) were the most effective. Figure 3 In (c), the undialyzed divalent iron content was determined, and the results showed that the undialyzed divalent iron content of whole sheep milk fortified with stachyose was the highest, at 2.80 mg / L, followed by fructo-oligosaccharides (2.53 mg / L) and xylo-oligosaccharides (2.50 mg / L), indicating that these three prebiotics were good at reducing iron to divalent iron, but they did not increase the absorption of divalent iron, and they were good at stabilizing divalent iron. Fructo-oligosaccharides (3.14 mg / L) were effective in fortifying skim sheep milk, but undialyzed divalent iron is not the main indicator of iron bioavailability. Figure 3 In (d), the five different prebiotics all increased the total divalent iron content in sheep milk. The total divalent iron content of whole sheep milk fortified with fructo-oligosaccharides was 5.51 mg / L, and the total divalent iron content of skim sheep milk fortified with isomalto-oligosaccharides was the highest, at 5.770 mg / L, followed by fructo-oligosaccharides (5.35 mg / L). Figure 4 In (e), the ratio of dialyzable divalent iron to dialyzable total iron in whole sheep milk and skim sheep milk fortified with the five prebiotics all increased to varying degrees. Isomalto-oligosaccharides fortified whole sheep milk had the best ratio, at 85.4%, which was 25.4% higher than the group with only iron. Stachyose fortified skim sheep milk had the best ratio, which increased from 68.5% to 81%. Considering the effects of the five prebiotics on the fortification of sheep milk with ferrous gluconate, fructo-oligosaccharides were significantly better than the other prebiotics in promoting the absorption of iron in sheep milk fortified with ferrous gluconate.
[0168] Figure 4 The dialyzable divalent iron content (a), dialyzable total iron content (b), undialyzed divalent iron content (c), total divalent iron content (d) and the ratio of dialyzable divalent iron to dialyzable total iron (e) of the functional sheep milk powder prepared in Examples 3-4 and Comparative Examples 5-8 were determined. The results are shown in Table 1. Figure 4(a) and (b) can be seen that for full-fat sheep milk, galacto-oligosaccharides, fructo-oligosaccharides, and isomalto-oligosaccharides can all promote iron absorption, among which galacto-oligosaccharides have the best effect, which can not only significantly increase the dialyzable total iron (7.52 mg / L), but also reduce more trivalent iron to divalent iron, and the proportion of dialyzable divalent iron in dialyzable total iron can reach 65.6%; the dialyzable total iron content of the five prebiotic fortified skim sheep milk has different degrees of decrease, which shows that the prebiotic fortification in skim sheep milk system cannot promote total iron absorption, but galacto-oligosaccharides can improve the ability of divalent iron, and compared with other prebiotics, it has a certain divalent iron absorption promoting effect. Figure 4 (c) The results show that the five prebiotics significantly increase the undialyzed divalent iron of full-fat sheep milk, and the undialyzed divalent iron content of stachydrine fortified full-fat sheep milk is as high as 2.48 mg / L, but its dialyzable divalent iron content is the lowest, which is similar to the effect of stachydrine fortified ferrous gluconate, indicating that stachydrine can reduce the iron in full-fat sheep milk to divalent iron as much as possible, but the absorbable iron is less; the undialyzed divalent iron content of galacto-oligosaccharide fortified skim sheep milk is the highest, reaching 2.36 mg / L, which is significantly higher than that of the group with only iron agent (2.19 mg / L). Figure 4 (d) In full-fat / skim sheep milk, the total divalent iron content of galacto-oligosaccharide fortified is the highest, which is 6.94 mg / L and 6.31 mg / L respectively, indicating that in the sheep milk system, galacto-oligosaccharides can better reduce trivalent iron to divalent iron, and the reduction effect is the best, followed by fructo-oligosaccharides. Figure 5 (e) In the five prebiotic fortified full-fat sheep milk, the ratio of dialyzable divalent iron to dialyzable total iron has different degrees of increase. Among them, the ratio of galacto-oligosaccharide fortified full-fat sheep milk is the best, reaching 65.6%, which is 14.5% higher than that of the group with only iron agent; the ratio of prebiotic fortified skim sheep milk ranges from 50.9% to 62.9%, and the best one is galacto-oligosaccharide, which is significantly different from the group with only iron agent (41%), and is increased by 53.4%. Overall, galacto-oligosaccharides have the best effect on the influence of sodium ethylenediaminetetraacetate fortified sheep milk, and the effect of galacto-oligosaccharides on promoting sodium ethylenediaminetetraacetate fortified sheep milk iron absorption is significantly higher than that of other prebiotics.
[0169] Figure 5 The dialyzable divalent iron content (a), dialyzable total iron content (b), undialyzed divalent iron content (c), total divalent iron content (d), and the ratio of dialyzable divalent iron to dialyzable total iron (e) of the functional sheep milk powder prepared in Examples 5-6 and Comparative Examples 1, 3, 9-10. Figure 5(a) It is known that different oils have different effects on iron absorption after fortifying sheep milk. The dialyzable iron content of defatted sheep milk fortified with oils increased significantly, but the effects were different. The dialyzable iron content of full-fat sheep milk fortified with tea seed oil, tomato seed oil and peony seed oil was similar, with the highest being tomato seed oil at 3.33 mg / L. The dialyzable iron content of defatted sheep milk fortified with oils ranged from 1.60 mg / L to 3.16 mg / L, with the highest being tomato seed oil, which was 118.6% higher than the group with only iron added (1.45 mg / L), followed by tea seed oil at 3.03 mg / L, which was 109.6% higher than the group with only iron added. According to Figure 5 (b) As shown, the dialyzable total iron content of full-fat sheep milk fortified with tea seed oil, tomato seed oil and peony seed oil was the best, and the results were similar to the dialyzable divalent iron content. The dialyzable divalent iron content was 32% higher than the group with only iron added, and the dialyzable total iron content was 6.7% higher than the group with only iron added. The absorption of total iron was less than that of divalent iron, indicating that these three functional factors could promote more iron absorption and were more conducive to the reduction of trivalent iron to divalent iron. The dialyzable total iron content of defatted sheep milk fortified with oils ranged from 2.42 mg / L to 3.93 mg / L, with the best being tomato seed oil. Even the worst, peony seed oil, increased by 14.9%. Among the six oils, peony seed oil fortified full-fat sheep milk was better, while its defatted sheep milk was slightly worse, indicating that the fat content in milk could affect the iron absorption of oil-fortified milk. Figure 5 (c) The undialyzed divalent iron content showed that the highest undialyzed divalent iron content of full-fat sheep milk fortified with oils was meta-bao-fengzi oil at 3.52 mg / L, followed by tea seed oil and peony seed oil at 2.19 mg / L. However, it is worth noting that the dialyzable divalent iron and dialyzable total iron content of meta-bao-fengzi oil were the lowest, indicating that although it could convert more trivalent iron to divalent iron, the absorption was actually reduced, which was not conducive to the functional factor of fortifying sheep milk iron absorption. The highest undialyzed divalent iron content of defatted sheep milk fortified with oils was macadamia oil (3.15 mg / L). Figure 5 (d) In the tea seed oil, peony seed oil and meta-bao-fengzi oil, the total divalent iron content of full-fat sheep milk fortified with oils was similar, at 5.45 mg / L, 5.45 mg / L and 5.62 mg / L, respectively, and the effect was better. The highest total divalent iron content of defatted sheep milk fortified with tomato seed oil was 6.08 mg / L, followed by tea seed oil (5.84 mg / L). Figure 6In (e), the ratio of dialyzable divalent iron to total dialyzable iron in the six different oil and fat fortified whole sheep milk is different to varying degrees. Except for the Junbao Fengzi oil, the ratio of the rest of the oil and fat fortified whole sheep milk is significantly improved, among which the ratio of the tomato seed oil is the highest, reaching 85%, which is 24.8% higher than that of the group with only iron agent (68.1%); the ratio of the tea seed oil fortified skim sheep milk is the highest, reaching 81.7%, followed by the tomato seed oil, 80.4%. Overall, the effect of the tomato seed oil on promoting the iron absorption of the ferrous gluconate fortified sheep milk is significantly higher than that of other functional oils.
[0170] Figure 6 The dialyzable divalent iron content (a), the total dialyzable iron content (b), the undialyzable divalent iron content (c), the total divalent iron content (d), and the ratio of the dialyzable divalent iron to the total dialyzable iron (e) of the functional sheep milk powder prepared for Examples 7-8 and Comparative Examples 5, 7, 11-12. Figure 6 In (a), the dialyzable divalent iron content of the skim sheep milk fortified by the functional oil is similar to that of the whole sheep milk, and the six functional oils can all improve the dialyzable divalent iron content of the skim milk. The dialyzable divalent iron content of the whole sheep milk fortified by the tea seed oil is the highest, reaching 5.80 mg / L, which is 40.3% higher than that of the group with only iron agent (4.13 mg / L); the dialyzable divalent iron content of the skim sheep milk fortified by the oil is 3.50 mg / L-5.66 mg / L, and the tea seed oil is the highest. Figure 6 In (b), the highest dialyzable total iron content of the whole sheep milk fortified by the functional oil is the Mufanggu oil, reaching 8.56 mg / L, followed by the tea seed oil, 7.77 mg / L. Compared with the tea seed oil, the ratio of the dialyzable divalent iron to the total dialyzable iron of the whole sheep milk fortified by the Mufanggu oil reaches 0.62 mg / L, while that of the tea seed oil reaches 0.75 mg / L, indicating that the tea seed oil has stronger trivalent iron ability and is more conducive to iron absorption. The highest dialyzable total iron content of the skim sheep milk fortified by the tomato seed oil is 8.98 mg / L, followed by the tea seed oil, 8.38 mg / L. Figure 6 In (c), the undialyzable divalent iron content of the four different sheep milk fortified by the six functional oils all increases to varying degrees. The highest undialyzable divalent iron content of the whole sheep milk fortified by the oil is the Junbao Fengzi oil, 4.12 mg / L, followed by the Mufanggu oil, 3.68 mg / L. The results are similar to those of the ferrous gluconate fortified by the oil and fat, that is, the Junbao Fengzi oil can promote the reduction of trivalent iron to divalent iron, but cannot make more iron be dialyzed and utilized. The undialyzable divalent iron content of the skim sheep milk fortified by the functional oil is more than 3 mg / L, which is the Mufanggu oil. Figure 6In (d), the total divalent iron content of sheep milk fortified with functional oils increased. The dialyzable divalent iron content of full-fat sheep milk fortified with M. oleifera oil was the highest, reaching 8.96 mg / L, which was 59.4% higher than that of the control group (5.62 mg / L). The total divalent iron content of defatted sheep milk fortified with tomato seed oil was the highest, reaching 8.04 mg / L, which was significantly different from that of the control group. Figure 7 In (e), the ratio of dialyzable divalent iron to total dialyzable iron in sheep milk fortified with functional oils increased. The ratio of dialyzable divalent iron to total dialyzable iron in sheep milk fortified with tea seed oil was the highest, reaching 74.7% for full-fat sheep milk and 67.5% for defatted sheep milk, which was 30.2% and 64.4% higher than that of the group with only iron added, respectively. This may be due to the oxidation of tea seed oil, which reduces the amount of iron nutrient fortifier reduced to divalent iron by gastric acid, reducing the amount of iron nutrient fortifier oxidized to trivalent iron, and maintaining the divalent iron form in the intestinal tract. Overall, tea seed oil had the highest effect on the fortification of sheep milk with sodium iron ethylenediaminetetraacetate, and tea seed oil significantly improved the iron absorption of sheep milk fortified with sodium iron ethylenediaminetetraacetate, which was significantly higher than that of other functional oils.
[0171] Test Example 2
[0172] The acid value of the fat in the sheep milk powder during storage was determined according to the method in GB 5530-2005 / ISO 660:1996 for the acid value and acidity of animal and vegetable fats and oils, and the result was expressed as KOH mg / g of fat.
[0173] Eight functional sheep milk powders and full-fat / defatted sheep milk powders were stored in a sealed and light-proof manner for 6 months, and the oil acid value during storage was determined every month.
[0174] The acid value of the functional sheep milk powders prepared in Examples 22-25 (SGTF, SETG, SSGTF, SSETG), Comparative Example 1 (SFG), Comparative Example 3 (SSG), Comparative Example 5 (SE), and Comparative Example 7 (SSE) was determined according to the above method after storage for 6 months, and full-fat sheep milk (S) and defatted sheep milk (SS) were used as the control group, and the results are shown in Table 1. Figure 7
[0175] As shown in Table 1, the acid value of the functional sheep milk powders prepared in Examples 22-25 (SGTF, SETG, SSGTF, SSETG), Comparative Example 1 (SFG), Comparative Example 3 (SSG), Comparative Example 5 (SE), and Comparative Example 7 (SSE) was determined according to the above method after storage for 6 months, and full-fat sheep milk (S) and defatted sheep milk (SS) were used as the control group, and the results are shown in Table 1. Figure 8 It can be seen that the acid values of the eight kinds of functional sheep milk powder have an upward trend during storage, and the growth rate continues to increase, indicating that the functional sheep milk powder has undergone a certain degree of hydrolysis during storage. There are some heat-resistant esterases remaining in the functional sheep milk powder, which are relatively stable in activity during storage, can hydrolyze milk fat to generate free fatty acids, cause the acid value of sheep milk powder to rise, and the small organic acids produced by the oxidation of fat also have a certain influence on the increase of the acid value of fat. At the same time, it can be observed that the acid value of the functional sheep milk during storage is higher than that of the whole fat / dairy sheep milk powder, indicating that the addition of iron agent and functional factors will accelerate the hydrolysis and oxidation of fat to different degrees. Among them, after six months of storage, the acid value of the corresponding formula milk powder of the two control whole fat / dairy sheep milk powder is the highest in the sheep milk powder only added with iron agent, which is due to the fact that even if the content of metal ions in food is lower than 0.1 ppm, it still has the ability to accelerate the oxidation of fat, among which iron ions and copper ions have the strongest pro-oxidation ability. The acid value of the functional sheep milk powder added with functional factors in the present application is lower than that of the corresponding iron agent only group, which indicates that the functional factors can effectively delay the increase of the acid value of the iron fortified sheep milk powder and inhibit the hydrolysis of fat in the iron fortified sheep milk powder.
[0176] Test Example 3
[0177] The fat TBA value was determined according to GB / T 5009.181-2003.
[0178] Eight kinds of functional sheep milk powder and whole fat / dairy sheep milk powder were sealed and stored in the dark for 6 months, and the TBA value during storage was determined every month.
[0179] The TBA value of the functional sheep milk powder prepared by the above method was determined for 6 months, and the whole fat sheep milk (S) and the skimmed sheep milk (SS) were used as the control group, and the results are shown in Table 1. Figure 8
[0180] It can be seen that the TBA values of the eight functional sheep milk powders showed an upward trend during storage. The TBA value reflects the content of malondialdehyde, a product of fatty acid oxidation in the sample. The greater the TBA value, the higher the content of malondialdehyde, and the more severe the degree of fat oxidation. Among them, the TBA of the functional sheep milk powder increased compared with the whole fat / skim sheep milk powder during storage. One month before storage, the TBA value of the ferrous gluconate sheep milk powder increased slowly, and the difference was not significant. After six months of storage, the TBA value of the group with only iron added was the highest. This may be due to the addition of only iron, which can catalyze the occurrence of fat oxidation. As the degree of fat oxidation increases, more hydroperoxides are degraded into small molecular substances such as malondialdehyde, causing the TBA value to increase. The TBA of the functional sheep milk powder with additional functional factors was lower than that of the corresponding group with only iron added, which indicated that the addition of functional factors can slow down the iron-promoted fat oxidation, and is more conducive to the long-term storage of sheep milk powder.
[0181] The above-described embodiments are merely preferred modes of the present application and are not intended to limit the scope of the present application. Various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art without departing from the design spirit of the present application shall fall within the scope of protection of the present application as defined by the claims.
Claims
1. A method of preparing a functional sheep milk powder, characterized by the steps of The application relates to a method for preparing functional sheep milk powder. The method comprises the following steps: adding an iron nutritional fortifier and a functional factor into sterilized sheep milk, homogenizing the mixture, and concentrating the mixture to obtain concentrated milk with a solid content of 45%-52%; spray-drying the concentrated milk to obtain the functional sheep milk powder; the sheep milk comprises fresh sheep milk or reconstituted sheep milk; the functional factor comprises functional oil and prebiotics; the iron nutritional fortifier comprises iron sodium ethylenediaminetetraacetate or ferrous gluconate, and the addition amount is 10-17.5 mg / L; the functional oil comprises tea seed oil or tomato seed oil, and the addition amount is 3-7.5 g / L; 2. The production method according to claim 1, characterized by, the prebiotics comprises fructo-oligosaccharide or galacto-oligosaccharide, and the addition amount is 3-6 g / L.
3. The production method according to claim 1, characterized by, The reconstituted sheep milk is prepared by mixing sheep milk powder and water to obtain a milk emulsion with a concentration of 18% w / w.
4. The production method according to claim 3, characterized by, The method further comprises a step of defatting the sheep milk. The defatting step comprises the following steps: centrifuging the sheep milk at 4000-5000 rpm at 2-6 DEG C for 10-20 min, filtering the sheep milk through four layers of gauze, and repeating the operation at least twice to complete the defatting of the sheep milk.
5. The functional sheep milk powder prepared by the method according to any one of claims 1-4.
Citation Information
Patent Citations
Fully functional nutritional supplement for pregnant and lying-in women
CN107348483A