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1.
To establish the naturally occurring range of insulin-like growth factor-I concentrations in bovine milk, samples from individual cows (n = 409) managed on five Missouri dairy herds were assayed. Parity, stage of lactation, and farm affected milk insulin-like growth factor-I concentration. Milk insulin-like growth factor-I concentration was higher in early lactation than mid and late lactation with concentrations in multiparous cows exceeding those in primiparous cows. Insulin-like growth factor-I concentration was negatively correlated to milk production the day of sample collection (r = -.15) and not correlated to predicted 305-d milk yields. Unprocessed bulk tank milk samples (n = 100) from a commercial processing plant had a mean concentration of insulin-like growth factor-I in milk of 4.32 ng/ml with a range of 1.27 to 8.10 ng/ml. This distribution was similar to the range detected in samples from individual cows, but values were lower than those reported for human milk. Concentration of insulin-like growth factor-I in milk was not altered by pasteurization (at 79 degrees C for 45 s). However, insulin-like growth factor-I was undetectable in milk heated to temperatures (121 degrees C for 5 min) required for infant formula preparation or in commercially available infant formula. These data indicated that insulin-like growth factor-I is a normal but quantitatively variable component of bovine milk that is not destroyed by pasteurization but is undetectable in infant formula. Concentration of insulin-like growth factor-I in bovine milk is lower than concentrations reported for human milk yet similar to those reported for human saliva.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
ABSTRACT: Iron, zinc, and calcium dialyzability from preterm and term starting infant formulas were determined after in vitro digestion, using special gastric conditions prevailing in preterm and newborn infants. Mineral dialyzability was studied using pH 2.0,3.5, and 4.5 for gastric digestion. The effect of gastric pH was more important on iron dialyzability (FeD) and zinc dialyzability (ZnD) than on calcium dialyzability (CaD). The effect on iron dialyzability was remarkable in fluid formulations with high digestibility: FeD was 18% to 20% when gastric digestion was made at pH 2, decreasing to 3% when made at pH 4.5. In most powder infant formulas with the lowest digestibility, FeD remained close to 10% despite variations in gastric digestion pH. Percent zinc dialyzability (ZnD%) steadily decreased when gastric digestion pH increased. At each pH, percent iron dialyzability (FeD%) and ZnD% from human milk were higher than those from infant formulas. Evaluation of mineral dialyzability from these infant formulas, using a gastric digestion pH prevailing in preterm and newborn infants, can provide valuable information on mineral availability.  相似文献   

3.
Human milk contains n-3 and n-6 LCPUFA (long chain polyunsaturated fatty acids), which are absent from many infant formulas. During neonatal life, there is a rapid accretion of AA (arachidonic acid) and DHA (docosahexaenoic acid) in infant brain, DHA in retina and of AA in the whole body. The DHA status of breast-fed infants is higher than that of formula-fed infants when formulas do not contain LCPUFA. Studies report that visual acuity of breast-fed infants is better than that of formula-fed infants, but other studies do not find a difference. Cognitive development of breast-fed infants is generally better, but many sociocultural confounding factors may also contribute to these differences. The effect of dietary LCPUFA on FA status, immune function, visual, cognitive, and motor functions has been evaluated in preterm and term infants. Plasma and RBC FA status of infants fed formulas supplemented with both n-3 and n-6 LCPUFA was closer to the status of breast-fed infants than to that of infants fed formulas containing no LCPUFA. Adding n-3 LCPUFA to preterm-infant formulas led to initial beneficial effects on visual acuity. Few data are available on cognitive function, but it seems that in preterm infants, feeding n-3 LCPUFA improved visual attention and cognitive development compared with infants receiving no LCPUFA. Term infants need an exogenous supply of AA and DHA to achieve similar accretion of fatty acid in plasma and RBC (red blood cell) in comparison to breast-fed infants. Fewer than half of all studies have found beneficial effects of LCPUFA on visual, mental, or psychomotor functions. Improved developmental scores at 18 mo of age have been reported for infants fed both AA and DHA. Growth, body weight, and anthropometrics of preterm and term infants fed formulas providing both n-3 and n-6 LCPUFA fatty acids is similar in most studies to that of infants fed formulas containing no LCPUFA. A larger double-blind multicenter randomized study has recently demonstrated improved growth and developmental scores in a long-term feeding study of preterm infants. Collectively, the body of literature suggests that LCPUFA is important to the growth and development of infants. Thus, for preterm infants we recommend LCPUFA intakes in the range provided by feeding of human milk typical of mothers in Western countries. This range can be achieved by a combination of AA and DHA, providing an AA to DHA ratio of approximately 1.5 and a DHA content of as much as 0.4%. Preterm infants may benefit from slightly higher levels of these fatty acids than term infants. In long-term studies, feeding more than 0.2% DHA and 0.3% AA improved the status of these fatty acids for many weeks after DHA; AA was no longer present in the formula, enabling a DHA and AA status more similar to that of infants fed human milk. The addition of LCPUFA in infant formulas for term infants, with appropriate regard for quantitative and qualitative qualities, is safe and will enable the formula-fed infant to achieve the same blood LCPUFA status as that of the breast-fed infant.  相似文献   

4.
为研究益生菌粉对婴儿配方奶粉渗透压带来的影响.对市售23款婴儿配方奶粉渗透压及其中6款婴儿配方奶粉冲调液强化益生菌粉后的渗透压进行了分析,并分析了相应冲调液5℃冷藏24 h的渗透压变化.结果表明市售婴儿配方和早产/低出生体重婴儿配方的渗透压范围为280~320 mOsm/kg·H2O,与母乳的渗透压水平范围一致,而乳蛋...  相似文献   

5.
Heat effects induced during the storage of enteral formula under laboratory and industrial conditions were evaluated using the following indicators: furosine; loss of available amino groups, measured by decrease in o-phthaldialdehyde (OPA) reactivity; fluorescence associated with the Maillard reaction (345 nm excitation, 415 nm emission); and colour (absorbance at 420 nm). The storage of formulas A and B (with different protein content) at 4, 20 and 30°C during 12, 24 and 36 weeks produced an increase in furosine values. Under industrial storage conditions at 55°C for between 1 and 12 weeks the behaviour of furosine differed between the two types of formulas. In Formula A (lesser protein content), there was a decrease in furosine level after the third week, whereas in formula B (greater protein content) a decrease was observed after the eighth week.
The loss of OPA reactivity reached 18% and 22%, respectively, for formula B and formula A stored at 30°C for 36 weeks. In adverse storage conditions (55°C), the loss of OPA reactivity reached 50%.
Fluorescence intensity (FI) and absorbance at 420 nm increased at all time/temperatures assayed. It reached values of 22.5 and 27.5 for FI and 0.161 and 0.173 for A420, respectively, for formula A and B, stored for 36 weeks at 30°C.
Furosine, loss of OPA reactivity, fluorescence intensity and colour are useful indicators of nonenzymatic browning during storage of enteral formulas.  相似文献   

6.
Non-enzymatic browning indicators were used to study thermal damage of protein during the processing of four types of infant formulas. The indicators analysed were furosine, available lysine, pyrraline, and fluorescence intensity. The infant formulas were prepared in industrial and pilot plants under the same conditions (formulation and processing) by a Spanish dietary product company. The furosine and fluorescence intensity increased in all formulas and stages of manufacture. Furosine content ranged from 55 to 1937 mg/100 g of protein. Available lysine loss during processing ranged from 10% to 35%, although available lysine values were higher than 5 g/100 g of protein. The fluorescence intensity indicator showed higher sensitivity for partially hydrolysed formulas. No pyrraline was detected in any of the formulas. Fluorescence intensity, furosine, and available lysine are proposed as useful indicators for monitoring heat damage of protein during the manufacture of infant formulas.  相似文献   

7.
Goat milk is used as an alternative to cow milk for the production of infant formulas. However, little is known about the protein quality and, specifically, about the digestible AA pattern of goat milk formulas compared with their cow milk counterparts. In this study, the true ileal AA digestibility of a goat milk infant formula was compared with a premium cow milk infant formula. The 3-wk-old piglet was used as a model for the 3-mo-old infant. Both milk formulas were prepared as described by the manufacturer, with titanium dioxide added as an indigestible marker. The formulas were fed to the piglets over a 2-wk trial period. Digesta from the terminal ileum were collected post euthanasia and analyzed for AA content, along with samples of the formulas. True AA digestibility was determined after correcting for endogenous AA loss at the terminal ileum of pigs fed an enzyme-hydrolyzed casein-based diet, followed by ultrafiltration (5,000 Da) of the digesta. Total urine and feces collection was also undertaken to determine the nitrogen retention from the diets. The true ileal AA digestibility was similar between the goat and cow milk infant formulas for all AA except Gly and Trp. There was no significant difference in the nitrogen retention of piglets fed the two different formulas. The goat milk infant formula and the premium cow milk infant formula were similar in terms of protein quality.  相似文献   

8.
Understanding the differences between the protein system of human milk and bovine milk is critical in the development of infant formulae. In this study, the proteins of bovine milk and a bovine-based whey-dominant infant formula were compared with those of human milk for infants born prematurely (pre-term) or at full term (term). The protein distribution of infant formula differed significantly from that of either type of human milk. A proteomic comparison between pre-term and term human milk showed a reduction of levels of β-casein and αs-casein and appearance of additional products, corresponding to low molecular weight hydrolysis products of the caseins, in pre-term milk. Pre-term milk samples also had higher total nitrogen concentration and plasmin activity, consistent with the proteomic data. These results suggest the operation of a physiological mechanism that may adjust enzyme and/or protein expression to modify protein digestibility, and may facilitate design of infant formulae, closer to maternal milk, particularly for premature infants.  相似文献   

9.
Pasteurization of milk ensures safety for human consumption by reducing the number of viable pathogenic bacteria. Although the public health benefits of pasteurization are well established, pro-raw milk advocate organizations continue to promote raw milk as "nature's perfect food." Advocacy groups' claims include statements that pasteurization destroys important vitamins and that raw milk consumption can prevent and treat allergies, cancer, and lactose intolerance. A systematic review and meta-analysis was completed to summarize available evidence for these selected claims. Forty studies assessing the effects of pasteurization on vitamin levels were found. Qualitatively, vitamins B12 and E decreased following pasteurization, and vitamin A increased. Random effects meta-analysis revealed no significant effect of pasteurization on vitamin B6 concentrations (standardized mean difference [SMD], -2.66; 95% confidence interval [CI], -5.40, 0.8; P = 0.06) but a decrease in concentrations of vitamins B1 (SMD, -1.77; 95% CI, -2.57, -0.96; P < 0.001), B2 (SMD, -0.41; 95% CI, -0.81, -0.01; P < 0.05), C (SMD, -2.13; 95% CI, -3.52, -0.74; P < 0.01), and folate (SMD, -11.99; 95% CI, -20.95, -3.03; P < 0.01). The effect of pasteurization on milk's nutritive value was minimal because many of these vitamins are naturally found in relatively low levels. However, milk is an important dietary source of vitamin B2, and the impact of heat treatment should be further considered. Raw milk consumption may have a protective association with allergy development (six studies), although this relationship may be potentially confounded by other farming-related factors. Raw milk consumption was not associated with cancer (two studies) or lactose intolerance (one study). Overall, these findings should be interpreted with caution given the poor quality of reported methodology in many of the included studies.  相似文献   

10.
Information about lipid oxidation in fresh and stored human milk compared with infant formulas is scarce. We aimed to assess n-6 and n-3 PUFA oxidation in these milks by measuring the 4-hydroxynonenal (4-HNE) and 4-hydroxyhexenal (4-HHE) content. Human milk samples (n = 4), obtained from volunteer mothers, were analyzed fresh and after 1 wk at 4 degrees C or 24 h at 18 degrees C. Vitamin E and malondialdehyde (MDA) were measured by HPLC and fatty acid profile by GC. The 4-HHE and 4-HNE contents were measured by GC-MS. Infant formulas (n = 10) were tested; their fat droplet size was measured by laser light scattering and observed by confocal laser scanning microscopy. Human milk samples contained 31.0 +/- 6.3 g/L of lipids and 1.14 +/- 0.26 mg/L of vitamin E. Fat droplets were smaller in infant formulas than reported in human milk. The (4-HHE/n-3 PUFA) ratio was 0.19 +/- 0.01 microg/g in fresh human milk (unchanged after storage) versus 3.6 +/- 3.1 microg/g in dissolved powder formulas and 4.3 +/- 3.8 microg/g in liquid formula. (4-HNE/n-6 PUFA) was 0.004 +/- 0.000 microg/g in fresh milk (0.03 +/- 0.01 microg/g after storage) versus 1.1 +/- 1.0 microg/g in dissolved powder formulas and 0.2 +/- 0.3 microg/g in liquid formula. Infant formulas also contained more MDA than human milk. n-3 PUFA were more prone to oxidation than n-6 PUFA. Whether threshold levels of 4-HHE and 4-HNE would be of health concern should be elucidated.  相似文献   

11.
Pulsed electric fields (PEF) technology was used to pasteurize raw milk under selected treatments. Processing conditions were: temperature 20, 30, and 40 °C, electric field 30.76 to 53.84 kV/cm, and pulse numbers 12, 24, and 30 for skim milk (SM), and 12, 21, and 30 for whole milk (WM) (2 μs pulse width, monopolar). Physicochemical parameters (pH, electrical conductivity, density, color, solids nonfat [SNF]) and composition (protein and fat content) were measured after processing. Shelf life of SM and WM was assessed after processing at 46.15 kV/cm, combined with temperature (20 to 60 °C) and 30 pulses. Mesophilic and psychrophilic loads and pH were evaluated during storage at 4 and 21 °C. Results showed minor variations in physicochemical properties after processing. There was an interesting trend in SM in SNF, which decreased as treatment became stronger; similar behavior was observed for fat and protein, showing a 0.18% and 0.17% decrease, respectively, under the strongest conditions. Protein and fat content decreased in WM samples treated at 40 °C, showing a decrease in protein (0.11%), and an even higher decrease in fat content. During storage, PEF-treated milk samples showed higher stability at 4 °C with minor variations in pH; after 33 d, pH was higher than 6. However samples at 21 °C showed faster spoilage and pH dropped to 4 after 5 d. Growth of mesophilic bacteria was delayed in both milks after PEF processing, showing a 6- and 7-log cycles for SM and WM, respectively, after day 25 (4 °C); however, psychrophilic bacteria grew faster in both cases. PRACTICAL APPLICATION: Pulsed electric fields (PEF) technology in the pasteurization of liquid food products has shown positive results. Processing times can be reduced considerably, which in turn reduces the loss of nutrients and offers important savings in energy. PEF has been used successfully to pasteurize some liquid foods, but it is still not used commercially in milk pasteurization, although several trials have shown the positive effects of PEF milk pasteurization, which could allow for its future use at the industrial level.  相似文献   

12.
《Journal of dairy science》2022,105(8):6548-6562
Ultrasonic technology presents a promising novel tool in the food industry for the processing of milk and dairy products. In this study, we investigated the effects of ultrasonication (US) as an alternative to thermal pasteurization for stabilization of the bioactive properties of camel milk. Camel and bovine milk samples were subjected to US at 6 different power levels (US1–US6), and 1 set of each type of milk was concurrently subjected to flash heat pasteurization (FHP) for comparative analysis (100 mL; n = 4). The microbiological and bioactive parameters of the samples were analyzed during 7 d of storage at 4°C. In both milk types subjected to US ≥ 140 W (US3), the bacterial load was reduced by almost 4 log cycles and complete reduction of microbial load was achieved with US = 170 W and US = 210 W (US5 and US6 treatments, respectively). No significant changes in protein patterns were observed with either FHP or US treatment. In addition, bioactive properties (cholesteryl esterase and pancreatic lipase inhibition) were either enhanced or retained at US3 or higher. 2,2′-Azino-bis-3-ethylbenzthiazoline-6-sulfonic acid and ferric reducing antioxidant power activities in camel milk were decreased after FHP treatment but increased or retained upon US, particularly at US3 and US4 (160 W). Overall, under our experimental conditions, US4 was effective in completely reducing the microbial count, while concomitantly retaining different bioactive properties of both camel and bovine milk. These outcomes highlight the potential of US at 160 W as an efficient nonthermal alternative processing method for milk.  相似文献   

13.
李晓东  潘悦  刘璐  朱启鹏 《食品科学》2021,42(21):372-379
乳脂肪球膜(milk fat globule membrane,MFGM)是包裹在天然乳脂肪球外部的3 层膜状结构,然而牛乳基和大豆基婴儿配方奶粉缺少MFGM,脂肪球结构与母乳存在较大差异,因此添加外源MFGM以及制备与母乳脂肪球结构接近的婴儿配方奶粉成为了近期的研究焦点。本文综述了MFGM的相关特性和生产开发途径,以及牛乳MFGM在仿母乳脂肪球结构乳液和婴儿配方奶粉中的应用。体外模拟婴儿胃肠道消化实验以及啮齿动物体内实验结果表明,仿母乳脂肪球结构乳液和婴儿配方奶粉能够促进婴儿脂肪消化并且改善脂质代谢过程。  相似文献   

14.
Huri Ilyasoglu  Beraat Ozcelik 《LWT》2011,44(4):999-1004
The aim of this study was to synthesize human milk fat substitute (HMFS) enriched with medium-chain fatty acids (MCFAs) by Lipozyme® RM IM-catalyzed acidolysis. The reaction substrates (tripalmitin, hazelnut oil fatty acids and Neobee® fatty acids) were specially chosen to mimic human milk fats and to enrich HMFS with MCFAs. Substrate molar ratio, reaction temperature and enzyme content were used to model and to optimize the reaction conditions via response surface methodology. The experiment was carried out at the optimal condition generated from the model yielded structured lipids with caprylic acid (12.8 g/100 g), capric acid (10.6 g/100 g) and palmitic acid (30 g/100 g). These values were found similar to the values predicted by the model (15.9 g/100 g, 14.1 g/100 g and 33.3 g/100 g). It can be concluded that the potential use of the structured lipids (SLs) produced in infant formulas provide energy source delivering a reduced calorie value for newborn, term and preterm infants.  相似文献   

15.
Donor human milk is the first alternative for preterm infants when mother's own milk is not available. Most available human milk banking guidelines recommend classical holder pasteurization to ensure safety by eliminating potential infectious microorganisms. Processing by heat treatment, however, negatively affects functionality and availability of bioactive components naturally present in human milk. Here we compared the effect of five different processing methods on the ability of human milk to induce blood plasma clotting, which was recently described as a bioactive function present in human milk. From thirty lactating women, milk samples were collected, and all milk samples were subjected to holder pasteurization (30 min at 62.5 °C), high-temperature-short-time pasteurization (15 s at 72 °C), high-pressure processing (5 min at 500 MPa), ultraviolet-C irradiation (4863 J/L), or thermo-ultrasonication (6 min at 60 W, at 40 °C). All methods significantly reduced the ability of milk to trigger blood plasma clotting compared to untreated milk, but ultraviolet-C irradiation and high-pressure processing were best at preserving this activity. Taken together, measuring the ability of milk to induce blood plasma clotting may offer a new tool to monitor the effect of human milk processing.  相似文献   

16.
Two commercially available soybean protein isolates were compared with regard to their allergenicity and their subcomponent differences. Isolate (A) is used in commercially prepared liquid infant formulas and isolate (B) in powdered infant formulas. Sera from four children with soy protein hypersensitivity and from five infants with soy protein-induced enterocolitis were used for in vitro testing. ELISA results show that specific IgE and IgG antibodies to isolate (A) were significantly higher than to isolate (B) in all groups. In SDS polyacrylamide gel electrophoresis, isolate (A) has bands representing the subunits of 7S (B-conglycinin) and the acidic and basic subunits of 11S; isolate (B) had only much smaller molecular weight compounds. Thus, there may be a difference in the allergenicity of liquid and powdered infant formulas.  相似文献   

17.
Milk samples were collected from 35 mothers delivering preterm infants and from 35 mothers delivering term infants at 3 time intervals over the first 3 weeks of lactation. The samples were collected by manual expression from both breasts into polyethylene containers and were frozen at ?20 °C and stored for analysis. The protein content of preterm milks during the first and second weeks is higher than that of term milk (P < 0.05) The fat and lactose contents during the first week are slightly more in term milk than in preterm milk. During the third week the fat content of preterm milk is higher but its lactose content was lower. All these differences are not significant. These results are discussed.  相似文献   

18.
This study evaluated the ability of spore-forming Bacillus spp. to resist milk pasteurization conditions from 72 to 150 degrees C. Spores from the avirulent surrogate Sterne strain of Bacillus anthracis, as well as a representative strain of a common milk contaminant that is also a pathogen, Bacillus cereus ATCC 9818, were heated at test temperatures for up to 90 min in dH2O, brain heart infusion broth, or skim milk. In skim milk, characteristic log reductions (log CFU per milliliter) for B. anthracis spores were 0.45 after 90 min at 72 degrees C, 0.39 after 90 min at 78 degrees C, 8.10 after 60 min at 100 degrees C, 7.74 after 2 min at 130 degrees C, and 7.43 after 0.5 min at 150 degrees C. Likewise, log reductions (log CFU per milliliter) for viable spores of B. cereus ATCC 9818 in skim milk were 0.39 after 90 min at 72 degrees C, 0.21 after 60 min at 78 degrees C, 7.62 after 60 min at 100 degrees C, 7.37 after 2 min at 130 degrees C, and 7.53 after 0.5 min at 150 degrees C. No significant differences (P < 0.05) in thermal resistance were observed for comparisons of spores heated in dH2O or brain heart infusion broth compared with results observed in skim milk for either strain tested. However, spores from both strains were highly resistant (P < 0.05) to the pasteurization temperatures tested. As such, pasteurization alone would not ensure complete inactivation of these spore-forming pathogens in dH2O, synthetic media, or skim milk.  相似文献   

19.
Infant formula is used as a supplement for newborns. Although bovine milk-based infant formulas dominate the market, caprine milk-based infant formula has attracted increasing attention because of its lower allergenicity. This study compared the digestive peptidome of bovine and caprine milk serum proteins by using in vitro infant simulating conditions. The result showed that the degradation pattern of milk proteins was similar, whereas the digestive rates of milk proteins differed between bovine and caprine milks. Several proteins, such as α-lactalbumin (LALBA), β-lactoglobulin (LGB), serum amyloid A protein (SAA1), glycosylation-dependent cell adhesion molecule 1 (GLYCAM1), and lactotransferrin (LTF), released more peptides during digestion of caprine milk serum than during digestion of bovine milk serum; however, more peptides derived from αS1-casein (CSN1S1) were found in bovine digesta. In addition, antimicrobial-related peptides were mostly only found in caprine intestinal digesta. The results of this study may be useful in understanding the digestion characteristics of milk serum proteins and providing guidance on the improvement of infant formula.  相似文献   

20.
A preparation of Bacillus anthracis (Sterne strain) spores was used to evaluate commercially available reagents and portable equipment for detecting anthrax contamination by using real-time PCR and was used to assess the fate of spores added directly to bulk tank milk. The Ruggedized Advanced Pathogen Identification Device (RAPID) was employed to detect spores in raw milk down to a concentration of 2,500 spores per ml. Commercially available primers and probes developed to detect either the protective antigen gene or the lethal factor gene both provided easily read positive signals with the RAPID following extraction from milk with a commercially available DNA extraction kit. Nucleotide sequence analysis of the vrrA gene with the use of DNA extracted from spiked milk provided molecular data that readily identified the spores as B. anthracis with a 100% BLAST match to the Sterne and Ames strains and easily distinguished them from B. cereus. Physical-fate and thermal-stability studies demonstrated that spores and vegetative cells have a strong affinity for the cream fraction of whole milk. A single treatment at standard pasteurization temperatures, while 100% lethal to vegetative cells, had no effect on spore viability even 14 days after the treatment. Twenty-four hours after the first treatment, a second treatment at 72 degrees C for 15 s reduced the viability of the population by ca. 99% but still did not kill all of the spores. From these studies, we conclude that standard pasteurization techniques for milk would have little effect on the viability of B. anthracis spores and that raw or pasteurized milk poses no obstacles to the rapid detection of the spores by molecular techniques.  相似文献   

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