Milk-based Infant Formula Research Articles

Analysis of nucleosides and nucleotides in infant formula by liquid chromatography–tandem mass spectrometry

A method for the simultaneous analysis of nucleosides and nucleotides in infant formula using reversed-phase liquid chromatography-tandem mass spectrometry is described. This approach is advantageous for compliance testing of infant formula over other LC-MS methods in which only nucleotides or nucleosides are measured. Following sample dissolution, protein was removed by centrifugal ultrafiltration. Chromatographic analyses were performed using a C18 stationary phase and gradient elution of an ammonium acetate/bicarbonate buffer, mass spectrometric detection and quantitation by a stable isotope-labelled internal standard technique. A single laboratory validation was performed, with spike recoveries of 80.1-112.9% and repeatability relative standard deviations of 1.9-7.2%. Accuracy as bias was demonstrated against reference values for NIST1849a certified reference material. The method has been validated for the analysis of bovine milk-based, soy-based, caprine milk-based and hydrolysed milk protein-based infant formulae.

Relative Bioavailability of a Paediatric Granule Formulation of the HIV Integrase Inhibitor Dolutegravir in Healthy Adult Subjects

This study evaluated the pharmacokinetics of a granule formulation of dolutegravir developed as an alternative to tablets for use in paediatric populations. A randomized, open-label study in healthy adults was carried out. Subjects received five treatments in a crossover design: a single dose of dolutegravir 50 mg as a tablet and dolutegravir 50 mg in 10 g of granule administered directly to mouth or mixed with purified water, water containing high cation concentrations or milk-based infant formula. Study treatments were separated by 7 days. Safety evaluations and serial pharmacokinetic sampling were done during each treatment period. A non-compartmental pharmacokinetic analysis was performed; geometric least-squares mean ratios and 90% CIs were generated for treatment comparison. Palatability was assessed by questionnaire. Plasma dolutegravir exposures in all granule treatment arms exceeded those of tablet formulation. The mean area under the curve from time 0 to infinity (AUC(0-∞)) and maximum concentrations were 55-83% and 62-102% higher, respectively. Pharmacokinetics were similar when dolutegravir was mixed with purified or cation-containing water. Dolutegravir was well tolerated, with no withdrawals due to adverse events. Taste was rated acceptable for all treatments. The exposure of dolutegravir after administration of granule formulation alone, with different types of water and with milk formula, exceeded that of the tablet. The similarity of dolutegravir exposure seen with the granule formulation demonstrates that dolutegravir granule can be given without restriction on the type of liquid or can be administered directly to the mouth (for example, when potable water is not available).

Estimation of Fluoride Intake From Milk-Based Infant Formulas and Baby Foods

The aim of this study was to examine the amount of fluoride ingested from infant formula and baby food in infants aged up to 6 months in South Korea. The fluoride content of 20 commercially available formulas and 8 baby food samples from 4 different brands was measured using a modified microdiffusion method and fluoride ion selective electrode. The amount of fluoride (F) ingested by infants was estimated assuming that the samples were reconstituted with water containing 0, 0.5, 0.8, and 1.0 ppm F. When the reconstituted formulas and baby foods contained 0.8 ppm F water, the infants were estimated to ingest fluoride in the range of 0.018 to 0.298 mg/kg/day. The findings of this study suggest that there is a need for clear guidelines for fluoride consumption by infants that should be followed by manufacturers and parents.

Multicenter validation of a mouse model for cow's milk allergy to assess the allergenicity of hydrolysed cow's milk based infant formulae

Background The EC-directive 2006/141/E requires objective and scientifically verified data to claim hypoallergenicity of hydrolysed formulae. However, no validated animal models are currently available to assess the residual sensitising capacity, although guinea pig assays are frequently used. This study is part of a multi-phase project which aims to validate a recently developed mouse model to assess the potential allergenicity of hydrolysed cow’s milk based infant formulae. The discriminatory power of a mouse allergy model for cow’s milk allergy to distinguish sensitizing properties of cow’s milk products was evaluated in 4 independent research centers. Methods C3H/HeOuJ mice were sensitised by oral administration of whey (WPC80) or extensively hydrolysed cow’ sm ilk (eWH) at weekly intervals for 5 weeks. One week after the last sensitisation, the acute allergic skin response (ear swelling at 1 hr), anaphylactic symptoms and temperature were determined upon intradermal ear injection of whey. Subsequently, mice were challenged orally with 50 mg whey and blood samples were taken after 30 min. Serum was analyzed for whey-specific immunoglobulins and mMCP-1. All protocols, test substances and procedures were standardised. Results All participating research laboratories detected elevated levels of whey-specific IgE/IgG1/IgG2a, serum mMCP-1 (reflection of mast cell degranulation) and acute allergic skin responses in whey sensitised animals. Anaphylactic symptoms and temperature drop were scored in 3 out of 4 research centers. In contrast, none of the evaluated parameters was altered in eWH-sensitized groups as compared to the vehicle control group.

Selenium content of Argentinean infant formulae and baby foods by pseudo-cyclic instrumental neutron activation analysis coupled to Compton suppression

The selenium levels of Argentinean infant formulae and baby food were measured using the 162-keV gamma-ray of 77mSe (t ½ = 17.4 s) by a pseudo-cyclic instrumental neutron activation analysis (PC-INAA) method in conjunction with Compton suppression spectrometry (CSS). For comparison purposes, 5 selected infant formulae were also analyzed for selenium by a radiochemical neutron activation analysis (RNAA) method. The selenium levels for three samples agreed between ±2.8 and 6.5 % while the other two differed by 12 and 17 % which could perhaps be attributed to sample inhomogeneity. The selenium content of cow milk-based infant formulae varied from 42–146 μg kg−1 compared to 52–63 μg kg−1 for soy-based milk formulae. In the case of baby foods, the selenium levels varied from 34 to 74 μg kg−1. The detection limits for selenium by PC-INAA–CSS for all the samples analyzed in this work were between 8.5 and 65 μg kg−1 depending on the major elements present in the samples, while it was 20 μg kg−1 for the RNAA method. The expanded uncertainty (κ = 2) of the PC-INAA–CSS method was 7.0 % at the end of cycle #4 for a sample containing 73.7 μg kg−1 selenium compared to the RNAA value of 24.2 % for a sample of 67.0 μg kg−1 selenium content.

Plasma carotenoid concentrations of infants are increased by feeding a milk‐based infant formula supplemented with carotenoids

Human milk is the gold standard of infant nutrition and is a source of important substances, including carotenoids. Infant formulas are designed to mimic the composition and/or performance of human milk, although currently carotenoids are not routinely added to US infant formulas. The aim of this study was to assess plasma concentrations of β-carotene, lutein and lycopene 56 days after feeding infants milk-based infant formula without (CTRL) or with different concentrations of added carotenoids (L1 and L2). Plasma carotenoid concentrations increased in infants fed carotenoid-supplemented formulas as compared with the control formula with no added carotenoids. At study day 56, infants fed the supplemented formulas (L1 and L2) had mean plasma lutein, β-carotene and lycopene concentrations that were within the range of a concurrent group of human milk-fed infants (HM). Anthropometric measurements were comparable among all study groups. Plasma carotenoid concentrations of infants fed the supplemented formulas were within the range of the HM group and are consistent with reported plasma carotenoid ranges in human milk-fed infants. The experimental formulas were well tolerated and anthropometric measurements were comparable among all study groups.

Complete genome sequence of Cronobacter sakazakii bacteriophage vB_CsaM_GAP161.

Cronobacter sakazakii is an opportunistic pathogen that causes infant meningitis and is often associated with milk-based infant formula. We have fully sequenced the genome of a newly isolated lytic C. sakazakii myovirus, vB_CsaM_GAP161, briefly named GAP161. It consists of 178,193 bp and has a G+C content of 44.5%. A total of 277 genes, including 275 open reading frames and two tRNA-encoding genes, were identified. This phage is closely related to coliphages RB16 and RB43 and Klebsiella pneumoniae phage KP15.

Energy and macronutrient content of familiar beverages interact with pre-meal intervals to determine later food intake, appetite and glycemic response in young adults

The objective was to compare the effects of pre-meal consumption of familiar beverages on appetite, food intake, and glycemic response in healthy young adults. Two short-term experiments compared the effect of consumption at 30 (experiment 1) or 120min (experiment 2) before a pizza meal of isovolumetric amounts (500mL) of water (0kcal), soy beverage (200kcal), 2% milk (260kcal), 1% chocolate milk (340kcal), orange juice (229kcal) and cow’s milk-based infant formula (368kcal) on food intake and subjective appetite and blood glucose before and after a meal. Pre-meal ingestion of chocolate milk and infant formula reduced food intake compared to water at 30min, however, beverage type did not affect food intake at 2h. Pre-meal blood glucose was higher after chocolate milk than other caloric beverages from 0 to 30min (experiment 1), and after chocolate milk and orange juice from 0 to 120min (experiment 2). Only milk reduced post-meal blood glucose in both experiments, suggesting that its effects were independent of meal-time energy intake. Combined pre- and post-meal blood glucose was lower after milk compared to chocolate milk and orange juice, but did not differ from other beverages. Thus, beverage calorie content and inter-meal intervals are primary determinants of food intake in the short-term, but macronutrient composition, especially protein content and composition, may play the greater role in glycemic control.

UPLC-ESI-MS/MS for determining trans- and cis-vitamin K1 in infant formulas: method and applications

A simple and sensitive method of determining vitamin K1 isomers (cis-and trans-forms) was developed for routine monitoring of supplemented infant formulas. The proposed method involves the applications of the lipase hydrolysis and the liquid-to-liquid extraction. After the hydrolysis and extraction procedures, the vitamin K1-enriched extract was directly injected into the ultra-performance liquid chromatography–tandem mass spectrometry system (UPLC-MS/MS). The components were detected using electrospray ionization (ESI) in positive-ion and quantified by multiple-reaction monitoring (MRM) mode. trans-vitamin K1 was separated from the biologically inactive cis-isomer through a C30 column (4.6 × 150 mm, 3 µm), and vitamin K1-d7 was used as an internal standard. Calibration curves were linear over the range of 9.3–464.75 ng ml−1 for trans-vitamin K1 (r2 > 0.999) and 1.71–85.25 ng ml−1 for cis-vitamin K1 (r2 > 0.999). The limit of detection for trans- and cis-vitamin K1 was 0.011 µg 100 g−1 and 0.01 µg 100 g−1. The limit of quantification was 0.037 µg 100 g−1 and 0.031 µg 100 g−1, respectively. The intra- and inter-batch variations (RSD%) were less than 5 %. The proposed method was applied to determine vitamin K1 isomers in milk-based, soy-based and rice-based infant formulas, and the cis-vitamin K1 isomer contributes to 7.05–17.21 % of the total vitamin K1 in certain infant formulas.

Quantitative Analysis of Intestinal Bacterial Populations From Term Infants Fed Formula Supplemented With Fructo‐oligosaccharides

Previous studies of infant formulas supplemented with oligosaccharides reported mixed results regarding the impact on intestinal microbial populations. The objective of this study was to examine the effect of supplementation of an infant formula with fructo-oligosaccharides (FOS) on select groups of intestinal bacteria in term infants. Four groups of infants were enrolled and fed human milk, a commercially available milk-based infant formula, or infant formula supplemented with 2.0 or 3.0 g/L FOS. Dietary intake, stool, and tolerance events were recorded. Fresh stool samples were collected approximately 27 days after feeding the diets (approximately 32 days after birth). Total bacteria, Bacteroides (as commensal bacteria), Bifidobacterium and Lactobacillus, and Clostridium difficile and Escherichia coli were quantified using respective specific real-time PCR assays. The formula feeding groups did not differ in stool consistency and stool frequency or frequency of spit-up or vomit during the entire study. The formula-fed infants tended to have more total bacteria in their stool samples than the human milk-fed infants. The formula-fed infants harbored a greater abundance of C difficile and E coli than the human milk-fed infants, but had a similar abundance of Bacteroides, Bifidobacterium, and Lactobacillus. The FOS supplementation at either dose did not significantly increase the bifidobacterial or lactobacilli populations, or decrease the populations of C difficile, E coli, or Bacteroides. The milk-based formula used in this study supported bifidobacterial and lactobacilli populations comparable with the human milk group; however, this formula did not suppress E coli or C difficile as effectively as human milk.

Analysis of Free and Total Myo-Inositol in Foods, Feeds, and Infant Formula by High-Performance Anion Exchange Chromatography with Pulsed Amperometric Detection, Including a Novel Total Extraction Using Microwave-Assisted Acid Hydrolysis and Enzymatic Treatment

A method for the analysis of free and total myo-inositol in foods, feeds, and infant formulas has been developed and validated using high-performance anion exchange chromatography with pulsed amperometric detection. The option of a free myo-inositol determination or a complete total myo-inositol determination from main bound sources can be achieved. These sources include phytates, lower'phosphorylated forms, and phosphatidylinositol. This approach gives the option for subtraction of myo-inositol from nonbioavailable sources when it is quantified using other methods if a total bioavailable myo-inositol result is desired for nutritional labeling of a product. The free analysis was validated in a milk-based infant formula, giving RSD(R) of 2.29% and RSD, of 2.06%. A mean recovery of 97.9% was achieved from various spike levels of myo-inositol. Certified National Institute of Standards and Technology reference material verified the method's compatibility and specificity. Two different total analyses were validated in a soy-based infant formula and compared. One technique involved using a conventional acid hydrolysis with autoclave incubation for 6 h, while the other used a novel technique of microwave-assisted acid hydrolysis with enzymatic treatment that can minimize extraction to 1 day. The autoclave analysis had RSD(R) of 2.08% and RSDr of 1.55%, along with a mean spike recovery of 102.1% at various myo-inositol spike levels. The microwave/enzyme total analysis had RSD(R) of 4.34% and RSD, of 4.70%, along with a mean spike recovery of 104.2% at various spike levels of myo-inositol. Main sources of myo-inositol including phytic acid and phosphatidylinositol were tested with both total analyses. Mean recoveries of phytic acid and phosphatidylinositol through the autoclave total analysis were 90.4 and 98.3%, respectively. Mean spike recoveries for these same sources in soy- based infant formula through the microwave/enzyme total analysis were 97.2 and 96.3%, respectively. Comparison of soy-based infant formula and corn grain samples with high levels of these main sources showed in similar results, indicating both total analyses are acceptable for use. An additional glycerol kinase step was also developed to remove glycerol from the chromatographic elution window of myoinositol in samples with high levels of glycerol.

Determination of Vitamin B12 in Infant Formula and Adult Nutritionals Using HPLC After Purification on an Immunoaffinity Column: First Action 2011.09

During the "Standards Development and International Harmonization: AOAC INTERNATIONAL Mid-Year Meeting," on June 29, 2011, the method "Determination of vitamin B12 in infant formula and adult nutritionals using HPLC after purification on an immunoaffinity column" was recommended by an Expert Review Panel and adopted as AOAC Official First Action status. The method is applicable for the determination of vitamin B12 in milk-based infant formula. Vitamin B12 is extracted from the sample in sodium acetate buffer in the presence of potassium cyanide. After purification and concentration with an immunoaffinity column (IAC), vitamin B12 is determined by LC with UV detection (361 nm). Data supplied by CLF demonstrated linear response over a wide range of concentrations (1.4-39 microg/100 mL). The analytical range is 0.2-10 microg/100 g, depending on the capacity of the IACs (0.01-0.5 microg), the input weight, and dilutions. Recovery rates were assessed using National Institute of Standards and Technology SRM 1849, and determined to be 95.1%, with SD of 0.34 and CV of 9.0. Measurement uncertainty (UE) was 0.8 microg/100 g, which was calculated from the validation data. It is an expanded measurement uncertainty and was obtained through multiplication with a coverage factor k. LOQ values were reported as 0.10 microg/100 g. The performance characteristics of the method met the standard method performance requirements set forth by the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals; thus, the method was determined to be appropriate for First Action status.

Cost-effectiveness of partially-hydrolyzed formula for prevention of atopic dermatitis in Australia

Objective:To perform an economic evaluation of a specific brand of partially hydrolyzed infant formula (PHF-W) in the prevention of atopic dermatitis (AD) among Australian infants.Methods:A cost-effectiveness analysis was undertaken from the perspectives of the Department of Health and Aging (DHA), of the family of the affected subject and of society as a whole in Australia, based on a decision-analytic model following a hypothetical representative cohort of Australian newborns who are not exclusively breastfed and who have a familial history of allergic disease (i.e., are deemed ‘at risk’). Costs, consequences, and incremental cost-effectiveness ratios (ICER) were calculated for PHF-W vs standard cow’s milk based infant formula (SF), and, in a secondary analysis, vs extensively hydrolyzed infant formula (EHF-Whey), when the latter was used for the prevention of AD.Results:From a representative starting cohort of 87,724 ‘at risk’ newborns in Australia in 2009, the expected ICERs for PHF-W vs SF were AU$496 from the perspective of the DHA and savings of AUD1739 and AU$1243 from the family and societal perspectives, respectively. When compared to EHF-Whey, PHF-W was associated with savings for the cohort of AU$5,183,474 and AU$6,736,513 from the DHA and societal perspectives.Limitations:The generalizability and transferability of results to other settings, populations, or brands of infant formula should be made with caution. Whenever possible, a conservative approach directing bias against PHF-W rather than its comparators was applied in the base case analysis. Assumptions were verified in one-way and probabilistic sensitivity analyses, which confirmed the robustness of the model.Conclusions:PHF-W appears to be cost-effective when compared to SF from the DHA perspective, dominant over SF from the other perspectives, and dominant over EHF-Whey from all perspectives, in the prevention of AD in ‘at risk’ infants not exclusively breastfed, in Australia.

Growth and tolerance of infants fed formula supplemented with polydextrose (PDX) and/or galactooligosaccharides (GOS): double-blind, randomized, controlled trial

BackgroundTo ensure the suitability of an infant formula as the sole source of nutrition or provide benefits similar to outcomes in breastfed infants, advancements in formula composition are warranted as more research detailing the nutrient composition of human milk becomes available. This study was designed to evaluate growth and tolerance in healthy infants who received one of two investigational cow’s milk-based formulas with adjustments in carbohydrate, fat, and calcium content and supplemented with a prebiotic blend of polydextrose (PDX) and galactooligosaccharides (GOS) or GOS alone.MethodsIn this multi-center, double-blind, parallel-designed, gender-stratified prospective study 419 infants were randomized and consumed either a marketed routine cow’s milk-based infant formula (Control; Enfamil® LIPIL®, Mead Johnson Nutrition, Evansville, IN) (n = 142) or one of two investigational formulas from 14 to 120 days of age. Investigational formulas were supplemented with 4 g/L (1:1 ratio) of a prebiotic blend of PDX and GOS (PDX/GOS; n = 139) or 4 g/L of GOS alone (GOS; n = 138). Anthropometric measurements were taken at 14, 30, 60, 90, and 120 days of age. Daily recall of formula intake, tolerance, and stool characteristics was collected during study weeks 1 and 2 and 24-h recall was collected at 60, 90, and 120 days of age. Medically-confirmed adverse events were recorded throughout the study.ResultsThere were no group differences in growth rate from 14 to 120 days of age. Discontinuation rates were not significantly different among study groups. No differences in formula intake or infant fussiness or gassiness were observed. During study weeks 1 and 2 and at 60 days of age stool consistency ratings were higher (i.e. softer stools) for infants in the PDX/GOS and GOS groups versus Control and remained higher at 120 days for the PDX/GOS group (all P < 0.05). The overall incidence of medically-confirmed adverse events was similar among groups.ConclusionsInvestigational routine infant formulas supplemented with 4 g/L of either a prebiotic blend of PDX and GOS or GOS alone were well-tolerated and supported normal growth. Compared to infants who received the unsupplemented control formula, infants who received prebiotic supplementation experienced a softer stooling pattern similar to that reported in breastfed infants.Trial registrationClinicalTrials.gov Identifier: NCT00712608

Perfil de triacilgliceroles y porcentaje de ácido palmítico en la posición sn-2 en sustitutos de leche materna

The aim of this study was to analyze the percentage of palmitic acid at sn-2 position on triacylglycerols in infant formulas. We studied 6 infant formulas in the Argentinean market that are used as breast-milk substitutes during the first six months after delivery: 2 formulas with vegetable oils as basic source of lipids (F1, F2); 1 formula with milk fat and vegetable oils (F3); 1 formula with structured lipids and vegetable oils (F4); 2 formulas for pre-term infants, one with milk fat and other oils (F5), and the other with vegetable oils (F6). Results showed that F1, F2, F3 and F4 presented 14.6%, 14.8%, 48.1% and 44.5%, respectively, of palmitic acid at sn-2 position, whereas formulas F5 and F6 had 49.5% and 14.6%, respectively, of palmitic acid at sn-2 position. Milk-based infant formulas had the highest concentration of palmitic acid at sn-2 position.

The effect of before meal consumption of fluid milks and substitutes on short‐term food intake, appetite and glycemic response in healthy young men and women

We hypothesized that consuming milk before and between meals compared with substitutes or orange juice is better for appetite and glycemic control. Two experiments compared the effect of consuming at 30 (Experiment 1) or 120 min (Experiment 2) before a pizza meal, isovolumetric (500 ml) amounts of water, soy beverage (SB; 200 kcal), 2% milk (M; 260 kcal), 1% chocolate milk (CM; 340 kcal), orange juice (OJ; 229 kcal) and cow's milk‐based infant formula (IF; 368 kcal) on appetite, food intake (FI) and blood glucose (BG) before and after a meal in healthy young men and women. Compared to water, all preloads reduced pre‐meal appetite (P = 0.0008). Pre‐meal ingestion of CM and IF reduced FI by 14% (880 ± 72 kcal) and 12% (905 ± 79 kcal), respectively (P = 0.0007) compared to water (1022 ± 75 kcal) at 30 min, but no preloads reduced FI at 2 h. Blood glucose was higher after CM than other caloric preloads from 0 to 30 min and after CM and OJ from 0 to 120 min (P &lt; 0.0001). Only M reduced post‐meal BG in both experiments (P &lt; 0.0001) and its effects were independent of meal time energy intake. Overall pre‐ and post‐meal BG was lower after M than after CM and OJ, but did not differ from water or IF (P = 0.005). Thus, pre‐meal consumption of 2% milk provided better glycemic response than other beverages, however, calorie content and inter‐meal intervals were primary determinants of their effects on FI.Grant Funding Source: Dairy Farmers of Ontario, Natural Sciences and Engineering Research Council of Canada (NSERC) and Kraft Canada

Food consumption and advanced β cell autoimmunity in young children with HLA-conferred susceptibility to type 1 diabetes: a nested case-control design

Evidence for the role of food consumption during childhood in the development of β cell autoimmunity is scarce and fragmentary. We set out to study the associations of longitudinal food consumption in children with the development of advanced β cell autoimmunity. Children with advanced β cell autoimmunity (n = 232) (ie, with repeated positivity for antibodies against islet cells) together with positivity for at least one of the other 3 antibodies analyzed or clinical type 1 diabetes were identified from a prospective birth cohort of 6069 infants with HLA-DQB1-conferred susceptibility to type 1 diabetes who were born in 1996-2004, with the longest follow-up to the age of 11 y. Repeated 3-d food records were completed by the families and daycare personnel. Diabetes-associated autoantibodies and diets were measured at 3-12-mo intervals. Four control subjects, who were matched for birth date, sex, area, and genetic risk, were randomly selected for each case. In the main food groups, only intakes of cow-milk products (OR: 1.05; 95% CI: 1.00, 1.10) and fruit and berry juices (OR: 1.09; 95% CI: 1.02, 1.12) were significantly, although marginally, associated with advanced β cell autoimmunity. The consumption of fresh milk products and cow milk-based infant formulas was related to the endpoint, whereas no evidence was shown for consumption of sour milk products and cheese. The intake of fat from all milk products and protein from fresh milk products was associated with risk of advanced β cell autoimmunity. Intakes of cow milk and fruit and berry juices could be related to the development of advanced β cell autoimmunity. This trial was registered at clinicaltrials.gov as number NCT00223613.

Excessive Leucine-mTORC1-Signalling of Cow Milk-Based Infant Formula: The Missing Link to Understand Early Childhood Obesity.

Increased protein supply by feeding cow-milk-based infant formula in comparison to lower protein content of human milk is a well-recognized major risk factor of childhood obesity. However, there is yet no conclusive biochemical concept explaining the mechanisms of formula-induced childhood obesity. It is the intention of this article to provide the biochemical link between leucine-mediated signalling of mammalian milk proteins and adipogenesis as well as early adipogenic programming. Leucine has been identified as the predominant signal transducer of mammalian milk, which stimulates the nutrient-sensitive kinase mammalian target of rapamycin complex 1 (mTORC1). Leucine thus functions as a maternal-neonatal relay for mTORC1-dependent neonatal β-cell proliferation and insulin secretion. The mTORC1 target S6K1 plays a pivotal role in stimulation of mesenchymal stem cells to differentiate into adipocytes and to induce insulin resistance. It is of most critical concern that infant formulas provide higher amounts of leucine in comparison to human milk. Exaggerated leucine-mediated mTORC1-S6K1 signalling induced by infant formulas may thus explain increased adipogenesis and generation of lifelong elevated adipocyte numbers. Attenuation of mTORC1 signalling of infant formula by leucine restriction to physiologic lower levels of human milk offers a great chance for the prevention of childhood obesity and obesity-related metabolic diseases.

Multiclass method for fast determination of veterinary drug residues in baby food by ultra-high-performance liquid chromatography–tandem mass spectrometry

A simple and rapid multiresidue method for the determination of different veterinary drug residues in meat-based baby food (MBF) and powdered milk-based infant formulae (PMIF) has been developed. The method involves an extraction procedure based on buffered QuEChERS (quick, easy, cheap, effective, rugged and safe) methodology, without any further clean-up step, followed by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The method has been validated in two baby food matrices (MBF and PMIF) at three different concentration levels, obtaining suitable recoveries and precision (inter and intra-day precision) values. Quantification was carried out using matrix-matched standard calibration. Furthermore, the decision limit (CCα) and the decision capability (CCβ) were evaluated, ranging from 0.5 to 16.2μg/kg and from 1.2 to 22.4μg/kg, respectively. Finally, the method was applied to the analysis of several kinds of baby food samples and traces of some veterinary drugs were detected.

Kinetics of Lysine Loss in an Infant Formula Model System at Conditions Applicable to Spray Drying

The kinetics of lysine loss at conditions applicable to spray drying were established for an infant formula model system. The composition of the model system was derived from the typical composition of milk-based infant formulas. The model system contained skim milk powder, lactose, and whey protein isolate as reactive compounds. The impacts of the water activity, temperature, time, and physical state on lysine loss were evaluated. The samples were equilibrated at water activities of 0.06–0.75 and then heated at 60–90°C for 30 s to 30 min. A maximum in lysine loss of 81% was observed at a water activity of 0.17 at 90°C and 30 min of heating. The water activity range of maximal lysine loss was shifted to higher water activities for lower heating temperatures. In order to study the impact of the physical state on lysine losses, the physical state of the model system was determined across the whole parameter range. For a water activity a w ≤ 0.17 the lactose contained in the model system did not crystallize at any experimental condition. Between water activities of 0.23 and 0.43 the lactose crystallized in the course of heating and the delay of crystallization was influenced by the temperature and the water activity. At water activities of 0.53 and 0.75 the lactose crystallized during the equilibration of the model system, i.e., before heating. The highest lysine losses were determined in the transition zone between the rubbery and the crystalline state.