Liquid Infant Formula Research Articles

Considerations regarding the use of infant formula products in infant and young child feeding in emergencies (IYCF-E) programs

Infants and young children are vulnerable in emergencies. The Operational Guidance on Infant and Young Child Feeding in Emergencies (OG-IFE) provides direction to governments, aid organisations and individuals on how to support the wellbeing of this population. The importance of breastfeeding in promoting child survival in emergencies cannot be overestimated. Therefore, the primary intervention in infant and young child feeding in emergencies (IYCF-E) is to support exclusive breastfeeding for infants 0-6 months and then continued breastfeeding alongside complementary feeding for children 6-24 months. However, non-breastfeeding children are vulnerable in emergencies and require intensive support. The OG-IFE outlines requirements and protocols to minimise the risks of artificial feeding in emergencies. This paper explains the reasoning behind, and the application of, these requirements. The OG-IFE emphasises that infant formula should not be provided unless breastfeeding is not possible and that except in extraordinary circumstances, individual assessment of the need for infant formula is required. It states that infant formula should be purchased and not donated and that neither follow-on formula nor toddler milks should be used. It notes that whether ready-to-use liquid infant formula or powdered infant formula is most suitable for a program will depend upon factors such as the availability of funds, of products, of water and fuel, and of storage facilities. It says that infant formula labelling should meet the requirements of the International Code of Marketing of Breastmilk Substitutes and be in the language of the recipient population, with appropriate instructions and warnings. It describes how caregivers should be discouraged from using bottles and supported to use easily cleanable cups for feeding infant formula. It notes that infant formula should be provided to infants unable to access breastmilk until they are at least 6 months of age. It also says that caregivers of formula-fed infants should be supported with a package of other resources to support safer feeding that includes: fuel, clean water, equipment for household preparation and feeding of infant formula, one-to-one education and demonstrations on safe preparation of infant formula feeds, and growth and health monitoring of the infant. It stresses that breastfeeding support should be provided alongside any artificial feeding program so as not to displace breastfeeding. Finally, it notes that in order to maximise effectiveness, IYCF-E requires a cross sectorial response with the involvement of various sectors, including child protection, water sanitation and hygiene (WASH), health, HIV, mental health and psychosocial support, education, disability, logistics, shelter, food security and livelihoods, and cash transfer programs.

Physicochemical Properties of Liquid Infant Formula Stored at Different Temperatures.

Changes in the physicochemical properties of ready-to-feed liquid infant formula (LIF) stored at different temperatures (10, 20, 30, and 40°C) for 6 mon, focusing on 5-hydroxymethylfurfural (HMF) content, color, pH, fat globule size distribution, and rheological properties were determined. The HMF content increased with storage time, and LIF stored at 40°C had a higher HMF content than that of LIF stored at 10°C. The lightness (L*) decreased while redness (a*) and yellowness (b*) increased with increasing HMF content. The fat globule size and pH of LIF stored at 10°C did not change. However, in the case of LIF stored at 30°C and 40°C, the fat globule size increased and the pH decreased during storage for 6 mon. LIF stored at 40°C had a higher apparent viscosity (ηa,10) than that of LIF stored at 10°C, and the shear-thinning behavior of LIF stored at higher temperature was stronger than that of LIF stored at low temperature. The physicochemical changes of LIF during storage were accelerated by Maillard reaction (MR) at higher storage temperatures. Therefore, even if LIF is aseptically manufactured, we recommend that sterilized LIF should be stored at low temperature in order to minimize quality changes during storage.

Contamination of dried blood spots - an underestimated risk in newborn screening.

Newborn screening (NBS) is an established screening procedure in many countries worldwide, aiming at the early detection of inborn errors of metabolism. For decades, dried blood spots have been the standard specimen for NBS. The procedure of blood collection is well described and standardized and includes many critical pre-analytical steps. We examined the impact of contamination of some anticipated common substances on NBS results obtained from dry spot samples. This possible pre-analytical source of uncertainty has been poorly examined in the past. Capillary blood was obtained from 15 adult volunteers and applied to 10 screening filter papers per volunteer. Nine filter papers were contaminated without visible trace. The contaminants were baby diaper rash cream, baby wet wipes, disinfectant, liquid infant formula, liquid infant formula hypoallergenic (HA), ultrasonic gel, breast milk, feces, and urine. The differences between control and contaminated samples were evaluated for 45 NBS quantities. We estimated if the contaminations might lead to false-positive NBS results. Eight of nine investigated contaminants significantly altered NBS analyte concentrations and potentially caused false-positive screening outcomes. A contamination with feces was most influential, affecting 24 of 45 tested analytes followed by liquid infant formula (HA) and urine, affecting 19 and 13 of 45 analytes, respectively. A contamination of filter paper samples can have a substantial effect on the NBS results. Our results underline the importance of good pre-analytical training to make the staff aware of the threat and ensure reliable screening results.

Safety assessment of the process '4PET', based on EREMA Basic technology, used to recycle post-consumer PET into food contact materials.

This scientific opinion of the EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF Panel) deals with the safety assessment of the 4PET recycling process (EU register number RECYC0139), which is based on the EREMA Basic technology. The input to this process is hot washed and dried poly(ethylene terephthalate) (PET) flakes originating from collected post‐consumer PET containers, containing no more than 5% PET from non‐food consumer applications. In this technology, post‐consumer washed and dried PET flakes are heated in a continuous reactor under vacuum before being extruded. Having examined the results of the challenge test provided, the Panel concluded that the continuous reactor step (step 2) is the critical step that determines the decontamination efficiency of the process. The operating parameters controlling its performance are well defined and are temperature, pressure and residence time. It was demonstrated that, depending on the operating conditions, the recycling process under evaluation is able to ensure that the level of migration of potential unknown contaminants into food is below a conservatively modelled migration of 0.15 μg/kg food, derived from the exposure scenario for toddlers. The Panel concluded that recycled PET obtained from the process is not of safety concern when the final thermoformed trays and containers and PET beverage bottles manufactured with the recycled pellets and not used for packaging water or ready‐to‐feed liquid infant formulae contain up to 90% recycled post‐consumer PET. These thermoformed trays are not intended to be used and should not be used in microwave and conventional ovens.

The carrageenan controversy

Except for Japanese nori, the production of seaweed hydrocolloids consumes the largest amount of macroalgae annually, and carrageenan is the largest consumer of this group. However, carrageenan has run into rough water with food processors and consumers, especially those who read ingredient labels. Carrageenan is being singled out on the Internet as being unsafe for human consumption, even though it is approved for food use by all major food regulatory agencies worldwide. Most recently, it has been approved for use in liquid infant formula, a particularly sensitive application when it comes to food safety. How did this negative attitude toward carrageenan evolve? It can be traced to a research group at the University of Illinois who claim that carrageenan upregulates inflammatory genes of the intestinal epithelium. There is no evidence that this in vitro model applies in vivo and a growing body of research is showing it does not. Nevertheless, it was picked up by various bloggers feeding on contradictory issues and quickly went viral. This paper describes the evolution of the “carrageenan controversy” and provides information for food producers and consumers on new more robust studies confirming that it is safe to consume foods containing carrageenan. This article also presents actions being taken by carrageenan producers and users, to reduce the noise in the public domain from the controversy.

Protein breakdown and release of β-casomorphins during in vitro gastro-intestinal digestion of sterilised model systems of liquid infant formula

Protein modifications occurring during sterilisation of infant formulas can affect protein digestibility and release of bioactive peptides. The effect of glycation and cross-linking on protein breakdown and release of β-casomorphins was evaluated during in vitro gastro-intestinal digestion (GID) of six sterilised model systems of infant formula. Protein degradation during in vitro GID was evaluated by SDS-PAGE and by measuring the nitrogen content of ultrafiltration (3kDa) permeates before and after in vitro GID of model IFs. Glycation strongly hindered protein breakdown, whereas cross-linking resulting from β-elimination reactions had a negligible effect. Only β-casomorphin 7 (β-CM7) was detected (0.187–0.858mgL−1) at the end of the intestinal digestion in all untreated IF model systems. The level of β-CM7 in the sterilised model systems prepared without addition of sugars ranged from 0.256 to 0.655mgL−1. The release of this peptide during GID was hindered by protein glycation.

Colorimetric detection of melamine based on p-chlorobenzenesulfonic acid-modified AuNPs

A highly selective and sensitive method is developed for colorimetric detection of melamine using gold nanoparticles (AuNPs) functionalized with p-chlorobenzenesulfonic acid. The addition of melamine induced the aggregation of AuNPs, as evidenced from the morphological characterizations and the color changed from red wine to blue, which could also be monitored by the UV–visible spectrometer and even naked eyes. This process caused a significant increase in the absorbance ratio (A650nm/A520nm) of p-chlorobenzenesulfonic acid–AuNPs. Under optimized conditions, the system exhibited a linear response to melamine in the range of 6.0 × 10−7–1.5 × 10−6 mol L−1 with a correlation coefficient of 0.997, and the limit of detection can even be 2.3 nM, which was much lower than some other methods and the safe limits (20 μM in both the USA and EU, 8.0 μM for infant formula in China, 1.2 μM in the CAC (Codex Alimentarius Commission) review for melamine in liquid infant formula). More importantly, the developed method presented excellent tolerance to coexisting common metal ions such as Ca2+, Zn2+, whose concentration is 1000 times of melamine, so that it had been applied to the analysis of melamine in liquid milk and milk powder with the recovery of 97.0–101 % and 100–103 %, respectively, indicating that the proposed method is quite a highly effective means to determine melamine in milk products.

Comparative thermal impact of two UHT technologies, continuous ohmic heating and direct steam injection, on the nutritional properties of liquid infant formula

A continuous pilot plant for liquid sterilization was used to compare ohmic heating and steam injection on liquid infant formula under the same conditions of pre-heating and holding. Samples were collected at different holding times and temperatures and analyzed for reactions of thermal degradation. Two substrates were measured: soluble proteins and vitamin C and different intermediate or advanced products of Maillard reaction were monitored: furosine, carboxymethyllysine (CML), FAST index (Fluorescence of Advanced Maillard products and Soluble Tryptophan) and color (ΔL*, Δa* and Δb*). Pseudo-zero order kinetics was established for the Maillard products or global markers and Arrhenius parameters could be calculated. Equivalent markers contents were obtained after ohmic heating and steam injection showing equivalent quality of the infant formula for both sterilization technologies.

Colorimetric detection of melamine in pretreated milk using silver nanoparticles functionalized with sulfanilic acid

Multiple methods have been published to detect melamine, only a few offer sensitivities below 50 nM with complicated procedures and sophisticated equipments. We demonstrate here a simple, rapid and lower-cost assay with high sensitivity for the melamine detection in milk samples using sulfanilic acid-modified silver nanoparticles (SAA-AgNPs). Due to the special chemical structures, SAA shows similar response to its analogues, which reveals that the selectivity and sensitivity of SAA itself is poor. However, the formation of SAA-AgNPs dramatically improves the selectivity of SAA and only melamine reacts with SAA-AgNPs. The possible mechanism is discussed. The interaction between exocyclic amine of melamine and SAA induces rapid aggregation of SAA-AgNPs accompanied by a naked-eye visible color change, resulting in precise quantification of melamine that can be monitored by a simple UV-visible spectrometer. Metal ions, amino acids and sugars that are common in milk have negligible interference influences. The extinction ratio (A620nm/A390nm) is correlated with the melamine concentration over the range of 0.1–3.1 μM. The detection limit is 10.6 nM, which is much lower than the safety limits (8 μM for infant formula in China, 20 μM in both the USA and EU and 1.2 μM in the CAC review for melamine in liquid infant formula). The method is applied successfully to determine melamine in pretreated milk products, indicating the potential practical use for the products suspected of melamine exposure.

Visual test for melamine using silver nanoparticles modified with chromotropic acid

A simple and low-cost assay for melamine is introduced that is making use of silver nanoparticles (AgNPs) functionalized with chromotropic acid (CTA). The surface of the AgNPs was capped with chromotropic acid which warrants the NPs to remain in stable and dispersed form. The presence of melamine induces the aggregation of the CTA-AgNPs due to the hydrogen bond interaction between CTA and melamine. This is accompanied by a color change from yellow to orange which can be observed with bare eyes. The method allows melamine to be quantified by absorptiometry with a linear response in the concentration range from 0.10 to 1.5 μM (R = 0.9996) and a detection limit of 36 nM which was much lower than the safe limits (20 μM in both the USA and EU, 8 μM for infant formula in China, 1.2 μM in the CAC review for melamine in liquid infant formula). The assay displays high selectivity to melamine over its structural analogs such as cyanuric acid, 2,4,6-trimethy-1,3,5-triazine, and phloroglucinol owing to the fact that only melamine can act as the hydrogen donor to form hydrogen bonds with the sulfo groups of the CTA-capped AgNPs. The method was successfully applied to the determination of melamine in spiked liquid milk and the average recovery was 99 %. Most amino acids and a high content of calcium do not interfere in this assay.

Feeding intolerance in preterm infants fed with powdered or liquid formula: a randomized controlled, double-blind, pilot study

Feeding intolerance (FI) is usually defined as "gastric residual volume of more than 50 % of the previous feeding volume, emesis, abdominal distension or both of these symptoms and a decrease, delay or discontinuation of enteral feedings." We aimed to compare the incidence of FI in preterm infants fed with powdered or liquid infant formula, and in a prospective, double-blind, pilot study, 78 preterm infants were randomized to receive powdered or liquid form of the same preterm infant formula. The primary outcomes were the incidence of FI in both groups. The pH of gastric fluids was measured in the fasting and postprandial periods on the seventh day of life, and gastrointestinal complications were recorded during the hospitalization period. The incidence of FI was significantly higher in infants fed with liquid formula (n = 34) when compared with infants fed with powdered formula (n = 44) [9 (26.5 %) vs 2 (4.5 %), p < 0.01, respectively]. The median fasting gastric fluid pH was significantly lower and postprandial gastric fluid pH was significantly higher than in infants fed with powdered formula (2.9 vs 3.4, p < 0.01 and 6.0 vs 5.9, p < 0.05 respectively). Infants fed with liquid formula regained birth weight significantly later than infants fed with powdered formula (9.5 vs 8.0 days, p < 0.01). Although the exact mechanisms are not clear, increased incidence of FI and delayed growth in the first weeks of life in preterm infants fed with liquid formula might be caused by altered gastric acidity or possible disrupted protein bioavailability due to different production and sterilization processes.

The Study in the Toxic Effects of the Material Bisphenol A at Long Time Exposure

Bisphenol a (BPA), is a chemical that has been used for more than 40 years in the manufacture of many hard plastic food containers such as baby bottles and reusable cups and the lining of metal food and beverage cans, including canned liquid infant formula. Therefore, it is very necessary to study its health risk and ecological risk. In this paper, four typical estrogen acceptor genes (AHR1, ESR1, VTG1 and VTG3) in female zebrafish liver were studied to assess the low dose and chronic effects of bisphenol A (BPA), with the method of quantitative real-time RT-PCR, and the ability of self regulation and repair of these genes were also discussed. The results showed that these genes could be induced even at 15 ug/L BPA, and VTG 3 was the most sensitive gene. VTG 3 and VTG 1 had obvious self repair and adjustment ability when BPA risk was removed. No monotonic dose-effect relationships of BPA were also found at this study.

Survey of total mercury in infant formulae and oral electrolytes sold in Canada

Total mercury (Hg) was measured in 150 infant formula products (as sold) and oral electrolyte solutions purchased in Canada in 2003. Results less than the limit of detection (LOD) were reported as the numeric value of the LOD. Electrolytes contained the lowest concentrations, averaging 0.026 ng/g. Average levels in milk-based ready-to-use, concentrated liquid and powdered concentrate were 0.028, 0.069 and 0.212 ng/g, respectively. In soy-based formulae, the respective mean concentrations were 0.049, 0.101 and 0.237 ng/g. These concentrations cannot be considered on an absolute basis because 76% of sample concentrations fell below the limit of detection. Despite the inability to measure many of the actual background concentrations, the method was sufficiently sensitive to identify clear cases of low-level Hg contamination (up to 1.5 ng/g) of individual lots of powdered formula. Also, all the different lots of one brand of concentrated liquid infant formulae had significantly higher concentrations of Hg than those of all other concentrated liquid products. After dilution with preparation water, the Hg concentrations in all products would be lower than the Canadian Drinking Water Guideline for Hg of 1 ng/mL and too low to impact on health.

Direct SERS detection of contaminants in a complex mixture: rapid, single step screening for melamine in liquid infant formula

Melamine can be detected in infant formula without the need for additional sample preparation or purification using a simple galvanic displacement reaction to fabricate portable silver SERS substrates. The reaction is rapid, inexpensive, and robust enough to perform well on highly heterogeneous common metal objects such as tape and coins.

Concentrations of bisphenol A in the composite food samples from the 2008 Canadian total diet study in Quebec City and dietary intake estimates

A total of 154 food composite samples from the 2008 total diet study in Quebec City were analysed for bisphenol A (BPA), and BPA was detected in less than half (36%, or 55 samples) of the samples tested. High concentrations of BPA were found mostly in the composite samples containing canned foods, with the highest BPA level being observed in canned fish (106 ng g−1), followed by canned corn (83.7 ng g−1), canned soups (22.2–44.4 ng g−1), canned baked beans (23.5 ng g−1), canned peas (16.8 ng g−1), canned evaporated milk (15.3 ng g−1), and canned luncheon meats (10.5 ng g−1). BPA levels in baby food composite samples were low, with 2.75 ng g−1 in canned liquid infant formula, and 0.84–2.46 ng g−1 in jarred baby foods. BPA was also detected in some foods that are not canned or in jars, such as yeast (8.52 ng g−1), baking powder (0.64 ng g−1), some cheeses (0.68–2.24 ng g−1), breads and some cereals (0.40–1.73 ng g−1), and fast foods (1.1–10.9 ng g−1). Dietary intakes of BPA were low for all age–sex groups, with 0.17–0.33 µg kg−1 body weight day−1 for infants, 0.082–0.23 µg kg−1 body weight day−1 for children aged from 1 to 19 years, and 0.052–0.081 µg kg−1 body weight day−1 for adults, well below the established regulatory limits. BPA intakes from 19 of the 55 samples account for more than 95% of the total dietary intakes, and most of the 19 samples were either canned or in jars. Intakes of BPA from non-canned foods are low.

Determination of perchlorate in infant formula by isotope dilution ion chromatography/tandem mass spectrometry

A sensitive and selective isotope dilution ion chromatography/tandem mass spectrometry (ID IC-MS/MS) method was developed and validated for the determination of perchlorate in infant formula. The perchlorate was extracted from infant formula by using 20 ml of methanol and 5 ml of 1% acetic acid. All samples were spiked with 18O4 isotope-labelled perchlorate internal standard prior to extraction. After purification on a graphitised carbon solid-phase extraction column, the extracts were injected into an ion chromatography system equipped with an Ionpac AS20 column for separation of perchlorate from other anions. The presence of perchlorate in samples was quantified by isotope dilution mass spectrometry. Analysis of both perchlorate and its isotope-labelled internal standard was carried out on a Waters Quattro Ultima triple quadrupole mass spectrometer operating in a multiple reaction monitoring (MRM) negative ionisation mode. The method was validated for linearity and range, accuracy, precision, sensitivity, and matrix effects. The limit of quantification (LOQ) was 0.4 µg l−1 for liquid infant formula and 0.95 µg kg−1 for powdered infant formula. The recovery ranged from 94% to 110% with an average of 98%. This method was used to analyse 39 infant formula, and perchlorate concentrations ranging from <LOQ to 13.5 µg l−1.

Emergency preparedness for those who care for infants in developed country contexts.

Emergency management organisations recognise the vulnerability of infants in emergencies, even in developed countries. However, thus far, those who care for infants have not been provided with detailed information on what emergency preparedness entails. Emergency management authorities should provide those who care for infants with accurate and detailed information on the supplies necessary to care for them in an emergency, distinguishing between the needs of breastfed infants and the needs of formula fed infants. Those who care for formula fed infants should be provided with detailed information on the supplies necessary for an emergency preparedness kit and with information on how to prepare formula feeds in an emergency. An emergency preparedness kit for exclusively breastfed infants should include 100 nappies and 200 nappy wipes. The contents of an emergency preparedness for formula fed infants will vary depending upon whether ready-to-use liquid infant formula or powdered infant formula is used. If ready-to-use liquid infant formula is used, an emergency kit should include: 56 serves of ready-to-use liquid infant formula, 84 L water, storage container, metal knife, small bowl, 56 feeding bottles and teats/cups, 56 zip-lock plastic bags, 220 paper towels, detergent, 120 antiseptic wipes, 100 nappies and 200 nappy wipes. If powdered infant formula is used, an emergency preparedness kit should include: two 900 g tins powdered infant formula, 170 L drinking water, storage container, large cooking pot with lid, kettle, gas stove, box of matches/lighter, 14 kg liquid petroleum gas, measuring container, metal knife, metal tongs, feeding cup, 300 large sheets paper towel, detergent, 100 nappies and 200 nappy wipes. Great care with regards hygiene should be taken in the preparation of formula feeds. Child protection organisations should ensure that foster carers responsible for infants have the resources necessary to formula feed in the event of an emergency. Exclusive and continued breastfeeding should be promoted as an emergency preparedness activity by emergency management organisations as well as health authorities. The greater the proportion of infants exclusively breastfed when an emergency occurs, the more resilient the community, and the easier it will be to provide effective aid to the caregivers of formula fed infants.

Enzyme-Linked Immunosorbent Assay Detection of Melamine in Infant Formula and Wheat Food Products

The adulteration of food products with melamine to inflate the nitrogen content necessitates the establishment of analytical methods that can distinguish between proteinaceous ingredients and such adulterants. The specificity and ability to detect melamine by two commercial enzyme-linked immunosorbent assay (ELISA) kits were evaluated along with three protocols for sample preparation. Both ELISAs displayed cross-reactivity with ammeline, but neither was able to detect ammelide or cyanuric acid, indicating either a requirement for the 4,6-diamino-1,3,5-triazine structure or inability to bind 1,3,5-triazine-4,6-diones. The limits of detection for melamine in powder infant formula ranged from 0.2 to 3 microg/g depending on the ELISA kit and the method used to prepare the sample. The limits of detection for melamine in liquid infant formula and wheat products were <1 microg/ml and <2.5 microg/g, respectively. The ELISA kits provide an effective alternative for the analysis of samples suspected of containing melamine without relying on extensive sample preparation or expensive instrumentation.

A rapid, acetonitrile-free, HPLC method for determination of melamine in infant formula

A simple, precise, accurate and validated, acetonitrile-free, reverse phase high performance liquid chromatography (HPLC) method is developed for the determination of melamine in dry and liquid infant formula. The separation is performed on a Kromasil C18 column (150 mm × 3.2 mm I.D., 5 μm particle size) at room temperature. The mobile phase (0.1% TFA/methanol 90:10) is pumped at a flow rate of 0.3 mL min −1 with detection at 240 nm. Melamine elutes at 3.7 min. A linear response ( r > 0.999) is observed for samples ranging from 1.0 to 80 μg mL −1. The method provides recoveries of 97.2–101.2% in the concentration range of 5–40 μg mL −1, intra- and inter-day variation in <1.0% R.S.D. The limit of detection (LOD) and limit of quantification (LOQ) values are 0.1 μg mL −1 and 0.2 μg mL −1, respectively.

Migration of bisphenol A from can coatings to liquid infant formula during storage at room temperature.

Information on migration of bisphenol A (BPA) from can coatings to foods during storage at room temperature is very limited, and the conclusions from the available studies are not always consistent. To investigate the effect of storage time on BPA migration from can coatings to liquid infant formula at room temperature, samples of 21 canned liquid infant formula products from different cans but the same lot as those analyzed for BPA previously were analyzed for BPA again after storage at room temperature for 10 months. Additional migration of BPA from can coatings to liquid formula during the 10-month storage period at room temperature was observed for 9 of the 21 products, with increases in BPA levels ranging from 29.8 to 110%. Significant differences between the 2007 and 2008 results (P = 0.026) were observed for only one brand of product, which had the lowest BPA levels in the 2007 survey. The BPA levels in the milk-based formula products analyzed in 2008 (mean, 6.8 ng/g) were significantly higher (P = 0.00023) than those in the milk-based formula products analyzed in 2007 (mean, 5.0 ng/g), whereas the differences in BPA levels between the soya-based formula products analyzed in 2008 (mean, 5.3 ng/g) and those analyzed in 2007 (mean, 5.8 ng/g) were not significant (P = 0.097). No obvious correlation between the product expiration date and the level of BPA migration from can coatings was observed.