Rapid authentication of characteristic milk powders by recombinase polymerase amplification assays

The authentication of dairy species has great significance for food safety. This study focused on a more rapid method for identifying major dairy species, and specific recombinase polymerase amplification (RPA)-based assays for cattle, goat, sheep, camel and donkey were developed. Through the developed RPA-based assays, goats and sheep could be simultaneously identified and bovine families could be differentiated. The performances of the RPA assays were validated using 37 milk powder samples, of which 16.2% (6/37) were suspected of being adulterated and 24.3% (9/37) were potentially at risk of being wrongly identified as adulteration. The effectiveness of the developed assays for crude DNA detection was also validated by a rapid nucleic acid extraction kit, and results showed that the presence of large amounts of protein and fat did not affect the qualitative results. Therefore, these assays could combine with the rapid nucleic acids extraction methods for being used in field detection.

Rapid classification of whole milk powder and skimmed milk powder by laser-induced breakdown spectroscopy combined with feature processing method and logistic regression

Whole milk powder and skimmed milk powder are suitable for different groups of people due to their differences in composition. Therefore, a rapid classification method for whole milk powder and skimmed milk powder is urgently needed. In this paper, a novel strategy based on laser-induced breakdown spectroscopy (LIBS) and feature processing methods combined with logistic regression (LR) was constructed for the classification of milk powder. A LR classification model based on mini-batch gradient descent (MGD) was employed first. As indicated by the research results, the accuracy of the MGD-LR model for the milk powder samples in the test set is 96.33% and the modeling time is 33.07 s. The modeling efficiency is low and needs to be improved. Principal components analysis (PCA) and mutual information (MI) were used as feature processing methods to reduce the high dimensional LIBS data into fewer features for improving the modeling efficiency of the classification model. The research results indicate that the accuracy of the PCA-MGD-LR model and the MI-MGD-LR model for the test set of milk powder samples was 99.33% and 99.67%, respectively. Compared with MGD-LR model, the modeling efficiency of PCA-MGD-LR and MI-MGD-LR models has increased by 89.7% and 74.8%, respectively. The results fully demonstrate the feasibility of rapid milk powder classification based on LIBS and feature processing methods combined with LR, and it will provide a new technology for the identification and classification of milk powder.

Crystal size, a key character of lactose crystallization affecting microstructure, surface chemistry and reconstitution of milk powder

Lactose crystallization during storage deteriorates reconstitution performance of milk powders, but the relationship between lactose crystallization and reconstitution is inexplicit. The objective of this study is to characterize crystalline lactose in the context of formulation and elucidate the complex relationship between lactose crystallization and powder functionality. Lactose in Skim Milk Powder (SMP), Whole Milk Powder (WMP) and Fat-Filled Milk Powder (FFMP) stored under 23 %, 53 % and 75 % Relative Humidity (RH) at 25  ℃ for four months was compared. Lactose, surface chemistry and microstructure of FFMP stored at 25 ℃ and 40 ℃ at 23 % to 75 % RH for four months were also analyzed and interpreted. At the same RH, FFMP crystallized in the same pattern as WMP. At 53 % RH, FFMP and WMP differentiated from SMP in terms of lactose morphology as well as the ratio between anhydrous α-lactose and anhydrous β-lactose. Lactose remained amorphous at 23 % RH, crystallized predominantly to α/β-lactose (1:4) at 40 to 58 % RH and to α-lactose monohydrate at 75 % RH. The crystallinity index was similar for all powders containing crystalline lactose. The estimated crystallite size increased from approx. 0.1 to 20 µm with increasing RH and temperature. When amorphous lactose crystallized into crystals below approx. 0.1 µm at 25 °C and 43 % RH, the microstructure and surface lipid were comparable to that of the reference powder. This powder reconstituted into a stable suspension system comparable to that of reference (well performing) powders. These results demonstrate that crystallite size is the key property linking lactose crystallization and reconstitution. Our finding thus indicates limiting crystallite size is important for maintaining desired product quality.

Flow of spore-forming bacteria between suppliers of dairy powders and users in some developing countries: challenges and perspectives

Abstract

Spore-forming bacteria are common contaminants of milk powder and processing lines and a major concern for the dairy industry. This dairy-associated microflora was studied extensively and well characterized in developed countries (exporters of milk powder), compared to developing countries (importers). Thereby, the quality issues affecting dairy powders and derived products are not fully controlled in developing countries. That is the case in Algeria, where recombined or reconstituted pasteurized milk is of low quality, reduced shelf-life, and the related dairies faced recurrent contaminations due to spores and biofilms. The transfer of spore-forming bacteria from exporters of dairy powders to importers in developing countries is an interesting topic, not thoroughly investigated. In addition, milk powder-based products are growing worldwide and their attributes, processes and technologies need to be better understood and controlled. This review analyzes issues affecting milk powder quality, based on few studies from developing countries in comparison with current knowledge, and emphasis on the case in Algeria. It provides information on how spore-forming bacteria and their biofilms affect the quality and shelf-life of recombined pasteurized milk produced in Algeria and compromise hygiene conditions in local dairy plants. Challenges and perspectives for better management of spore transfer from exporters of dairy powders to importers in developing countries are thereby outlined.

Highlights

The presence of spore-forming bacteria in milk powder is a serious safety issue.Spores are not well known, characterized and controlled in importers from developing countries.Spores cause recurrent contamination of pasteurized milk and biofilm issues in Algerian dairies.Challenges are how to reduce the flow of spores in milk powder trade.Perspectives on identification targeting predominant spores and improvement of biofilm removal.

Microplastics in infant milk powder

Microplastics can be found almost everywhere and extensively expose to human. Infants are vulnerable, and the potential risks of microplastics may be greater for infants, however, infants' microplastic exposure is still poorly understood. Since milk powder makes up a significant portion of many infants' diets, we investigated microplastic pollution in infant milk powder and calculated the microplastic exposure from milk powder, feeding bottles and milk powder preparation. On one hand, we studied 13 different types of milk powder with different packaging, processing systems, and milk sources. The boxed milk powder (7 ± 3 items/100 g) was more polluted with microplastics than the canned milk powder (4 ± 3 items/100 g). The inner packaging of the boxed milk powder was plastic and aluminum foil laminated, it emitted 8 ± 2 to 17 ± 1 items/100 g of microplastics, and might be a main source of microplastics in boxed milk powder. On the other hand, we found that when infants consume milk powder, the microplastic exposure from milk powder itself is little, exposure from feeding bottles is 6.8 times higher than that from milk powder and milk powder preparation is 1.7 times higher.

Plasma-activated milk powder as a sodium nitrite alternative in pork sausages

This study investigated the effect of plasma activated milk powder containing 1.3 g/kg nitrite as an alternative to sodium nitrite in stored pork sausages. Control samples (NC) did not contain a nitrite source, while the recipes of other treatments contained 100 ppm sodium nitrite (PC), 5% plasma activated milk powder (PAMP), and 5% plasma activated milk powder with 0.05% ascorbic acid (PAMP+AA). The obtained results showed both experimental groups were characterized by higher values of residual nitrite, nitrosylhemochrome and redness as well as similar or lower values of thiobarbituric acid reactive substances and total aerobic plate count compared to PC group after the storage period. Using ascorbic acid promoted reduction of nitrite content and extended the color stability of the samples compared to PAMP group without deteriorating the oxidative and microbiological quality of the product. Finally, sausages cured using the proposed alternative method exhibited higher cooking yield, lighter color, better texture, and different aroma profile (PCA) than those with sodium nitrite.

Green vortex-assisted emulsification microextraction using a ternary deep eutectic solvent for extraction of tetracyclines in infant formulas

A novel green alternative vortex-assisted emulsification liquid-liquid microextraction based on a new hydrophobic deep eutectic solvent (DES) was developed to extract tetracyclines in infant formulas. Five new ternary DESs were synthesized and tested in this regard. Among them [thymol]:[ethylene glycol]:[benzyl alcohol] (2:2:1) DES demonstrated the highest extraction efficiency. The analyzes were performed by HPLC. The DES was characterized by attenuated total reflectance-FTIR, nuclear magnetic resonance spectroscopy, and octanol-water partition coefficient. The effect of type, mole ratio, and volume of DES, dispersing agent, pH, and ionic strength was studied. The limits of quantification and linear range were 3-9.32 and 3-500 μg kg^-1, respectively. The method was applied to detect tetracyclines in infant formulas, and the recoveries were obtained as 68.9-102.0 % with relative standard deviations < 9 %. The procedure greenness was assessed using the Analytical Eco-Scale. This paper represents the first application of a novel ternary DES to analyze tetracyclines in infant formulas.

A novel polymeric fluorescence sensor based on acrylated citric acid for detection of melamine adulteration: Application in milk powder

Melamine selective acrylate citric acid (ACA) based polymeric membrane sensor was prepared by radical polymerization method and the sensor was characterized. The sensor showed a selective fluorescent response to melamine (λ_ex/λ_em = 388/425 nm). The sensor response is linear in the concentration range of 3.96 × 10^-9 to 7.93 × 10^-8 mol L^-1, the optimum pH value is 6.0 and response time is less than 1 min. Limit of detection (LOD) and limit of quantification (LOQ) were calculated as 2.32 × 10^-10 mol L^-1 and as 7.74 × 10^-10 mol L^-1, respectively. The sensor showed great selectivity towards melamine in the presence of a large number of molecules and ions. The performance of sensor was also confirmed by determining of melamine in milk powder sample and the results were compared with HPLC results and acceptable results were obtained. As a conclusion, the results revealed that the proposed sensor is an interesting alternative for melamine determination.

Probabilistic Health Risk Assessment of Trace Elements in Baby Food and Milk Powder Using ICP-OES Method

This study was conducted to evaluate the concentration and health risk of trace elements in milk powder and baby food samples marketed in Iran using inductive couple plasma/optical emission spectroscopy (ICP-OES) method. The limit of detection (LOD) and limit of quantification (LOQ) were ranged from 1.80 × 10^-5 to 2.17 × 10^-3 and 6.00 × 10^-5 to 7.22 × 10^-3 mg/kg, respectively, with recoveries ranged from 92 to 105%. Zinc (Zn) was found in a high mean concentration (8.49 × 10^-1 ± 3.93 × 10^-2 mg/kg) in milk powder, and iron (Fe) was found in the highest mean concentration (2.04 ± 3.61 × 10^-2 mg/kg) in baby food. The Monte Carlo simulation results for the infants revealed that the rank order of the hazard quotient (HQ) index was mercury (Hg) > nickel (Ni) > arsenic (As) > cadmium (Cd) > aluminum (Al). Further, the result of non-carcinogenic and probability of carcinogenic risk was lower than the limits of safe risk (HQ > 1 and cancer risk (CR) > 1 × 10^-4). In conclusion, the toxic elements content in the tested products was sufficiently low, and all of the milk powder and baby food sold in Iran could be considered safe for infants and children.

Microstructural and rheological behavior of buffalo milk chocolates

The development of products with buffalo milk has increased due to its peculiar characteristics, such as taste and high content of total solids, which has attracted consumers and the food industry.In this context, the objective was to develop and evaluate the microstructural properties of chocolates with different concentrations of buffalo milk powder (0%, 5%, 10%, 15% and 20%) through polymorphism, microscopy and rheological studies. For the polymorphism, the X-ray diffraction technique (XRD) was performed, while the crystal morphology was observed by scanning electron microscopy (SEM). The addition of levels of more than 10% buffalo milk caused notable changes in XRD diffractograms, demonstrating the appearance of different polymorphic forms. Microscopy analysis revealed changes in the structure of the matrix with an increase in the concentration of buffalo milk, presenting more continuous surfaces, associated with milk proteins, which have emulsifying capacity. The Herschel-Bulkley model adequately described the flow behavior of the formulations. There was an increase in all rheological properties (yield stress, viscosity, thixotropy and loss tangent (tang δ)) in chocolates with higher concentrations of milk. For that, the composition of the milk influences the degree of structuring of the chocolate. Considering this technological information, it is important to highlight that the production of buffalo milk chocolates shows potential for technological innovation.

Development of multi-species biofilm formed by thermophilic bacteria on stainless steel immerged in skimmed milk

Thermophilic bacteria, such as Bacillus licheniformis, Geobacillus stearothermophilus, Bacillus Subtilis and Anoxybacillus flavithermus, are detected frequently in milk powder products. Biofilms of those strains act as a major contamination to milk powder manufactures and pose potential risks in food safety. In this study, we explored the developing process of multi-species biofilm formed by the four thermophilic bacteria on stainless steel immerged in skimmed milk. The results showed that the thermophilic strains possessed strong capacities to decompose proteins and lactose in skimmed milk, and the spoilage effects were superimposed from multiple strains. B. licheniformis was the most predominant species in the mixed-species biofilm after 12-h incubation. From 24 h to 48 h, G. stearothermophilus occupied the highest proportion. Within the multi-species biofilm, competitive relation existed between B. licheniformis and G. stearothermophilus, while synergistic impacts were observed between B. licheniformis and A. flavithermus. The interspecies mutual influences on biofilm development provided important evidences for understanding colonization of the predominant thermophilic bacteria during milk powder processing.

Selective extraction and determination of Cr(VI) in food samples based on tandem electromembrane extraction followed by electrothermal atomic absorption spectrometry

In this study, electromembrane extraction (EME) combined with micro-EME (µ-EME) was used for the selective extraction of Cr(VI) from food samples (milk powder, Ocimum basilicum, and fish samples). Electrothermal atomic absorption spectrometry was used for the quantification of Cr(VI). Under the optimized extraction conditions, the extraction recovery of Cr(VI) was 73.7%. This proposed method provided a linear range from 0.01 to 5.0 ng/mL and the limit of detection (LOD) and limit of quantification (LOQ) were 0.003 and 0.010 ng/mL. The %RSD (n = 5) was in the range of 11.2-11.8% at 0.05, 1.0 and 2.5 ng/mL of Cr(VI), and the enrichment factor was 584. The accuracy of the method was evaluated by analysis of SRM 2700 as a certified reference material (CRM) and result was in good agreement with the certified value.

Fate of Salmonella and Enterococcus faecium during Pilot-Scale Spray Drying of Soy Protein Isolate

ABSTRACT

Outbreaks and recalls associated with microbial contamination of powdered foods have raised concern for the safety of the spray-drying process and its products. However, little research on the fate of bacteria during the spray-drying process has been done, leaving much unknown about the risks of contamination in spray dryers. Therefore, quantifying the contamination levels of Salmonella and Enterococcus faecium (as a surrogate) in various locations within a pilot-scale spray dryer can help illustrate the distribution of bacterial contamination, including in the final product. A 10% (w/w) dispersion of water and soy protein isolate was mixed with tryptic soy broth containing yeast extract inoculated with Salmonella enterica serovar Enteritidis phage type 30 (PT30) or E. faecium strain NRRL B-2354. This dispersion was spray dried using a pilot-scale tall-form cocurrent spray dryer at an inlet air temperature of 180, 200, or 220°C. After drying, samples of powder from eight locations within the system were collected or surface swabbed, plated, and enumerated. Spray drying achieved 2.40 to 4.15 and 2.33 to 2.83 log reductions in the concentrations of Salmonella and E. faecium, respectively, in the final powder product accumulated in the dryer's collectors. Salmonella and E. faecium were found in various concentrations in all locations within the spray dryer after a complete drying cycle. Differences in inlet air temperature between 180 and 220°C had no significant effect on the inactivation levels. As a surrogate, E. faecium was more resistant to spray drying than Salmonella. Overall, spray drying is capable of significant bacterial reduction in the final powder product, which can be combined with other hurdle technologies. However, adequate cleaning and sanitization procedures must be taken into consideration to prevent cross-contamination.

HIGHLIGHTS

Contribution of packaging materials to MOSH and POSH contamination of milk powder products during storage

Mineral oil hydrocarbons (MOH) in milk powders, particularly in infant formulas, have been and continue to be a major concern to the public worldwide. These contaminants are likely derived from environmental pollution, manufacturing process and packaging materials. In this study, 23 Chinese commercial milk powder products packaged in four types of materials, i.e. metal cans, paper containers, paperboard boxes with internal bags, and aluminium foil-plastic bags, were collected and stored for 1 year. The total and surface MOH in these samples were detected and compared before and after storage to understand the MOH migration during storage, despite no mineral oil saturated hydrocarbons (MOAH) were detected. The contents of mineral oil saturated hydrocarbons (MOSH) and polyolefin oligomeric saturated hydrocarbons (POSH) in metal cans were the least among the four packages and changed little during storage, which suggested that little MOH migration occurred in metal material. Despite all the food contact materials in the other three packagings were the aluminium foil-plastic composite, the similar low migration occurred in the aluminium foil-plastic bags and internally contained composite bag(s) in paperboard boxes. However, both total and surface MOSH and POSH easily migrated from the paper-plastic-aluminium composite of paper containers during storage. These findings are helpful for the selection of packaging materials in manufacturing milk powder products or other foods.

Revisiting the dynamics of proteins during milk powder hydration using asymmetric flow field-flow fractionation (AF4)

The dynamics of β-casein and casein micelles in the reconstitution of skim milk were revisited in this study. β-casein migrates into casein micelles upon an increase in temperatures due to an increase in the hydrophobic effect and lower calcium-phosphate cluster solubility. This process can be reversed upon cooling. These phenomena are well known in fresh milk and are not yet clearly established for reconstituted milk powder. As milk powder is commonly used as a functional ingredient in food products, it is of interest to investigate the migration of casein micelle β-casein to and from the serum phase in reconstituted milk. This study aimed to use asymmetrical flow field flow fractionation (AF4) in combination with various detectors to revisit the dynamics of β-casein when reconstituting skim milk at different temperatures. Fluorescence-labelled β-casein was added to fresh and reconstituted skim milk and rapid transport of β-casein into the outer shell of the casein micelles could be observed already after 5 ​min of reconstitution at 50 ​°C. This process stabilized after approximately 5 ​h, which indicates that an equilibrium of β-casein between the serum and the micellar phase was reached. Similar results were found for fresh milk. The apparent density of the casein micelles in the skim milk samples was also found to increase during reconstitution at 50 ​°C. During cold reconstitution of milk powders, the migration of β-casein to the serum was not observed. The results suggest that β-casein was already present in the serum phase upon reconstitution at 6 ​°C. When a sample was reconstituted for 180 ​min at 50 ​°C, the migration of β-casein back into the serum was observed upon cooling the same sample to 6 ​°C. The size of casein micelles in reconstituted milk at 6 ​°C was larger compared to reconstitution at 50 ​°C. With AF4 and the multi-detector approach, the change in concentration and size of casein micelles can be readily investigated and the migration of β-casein can be tracked simultaneously. Therefore, the method is a valuable tool for studies of the properties and changes in various milk samples.

Fast and simple determination of estrogens in milk powders by magnetic solid-phase extraction using carbon nitride composites prior to HPLC

A graphitic carbon nitride (g-C₃N₄/Fe₃O₄)-based magnetic solid-phase extraction (MSPE) approach was established for fast and simple analysis of estrogens in milk powders. The composites were characterized by X-ray diffractometer, scanning electron microscope, and Brunauer-Emmett-Teller surface area and pore size distribution analyzer. Compared with the bulk g-C₃N₄, g-C₃N₄/Fe₃O₄ gave a narrower distribution of mesopores and provided an enhanced surface area from 77.1 to 113.7 m²/g. Polar analytes of estrogens were selected as model compounds and the extraction of four estrogens was achieved in n-hexane using 15 mg of adsorbent within only 2 min. Possible extraction mechanism of g-C₃N₄/Fe₃O₄ for these estrogens was explored in terms of the polarity of the analytes and the adsorption performance of the adsorbent. The hydrophobicity and the hydrogen-bond interaction between the estrogens and g-C₃N₄ were responsible for the efficient adsorption. Combined with HPLC, MSPE with the prepared adsorbent gave the enhancement factors of 20 to 24 and the linear ranges of 2-200 μg/kg for 17β-estradiol and 17α-ethinylestradiol, 1.5-150 μg/kg for estrone, and 3-300 μg/kg for hexestrol. The detection limits and quantification limits for the estrogens in milk powders were 0.5-0.9 μg/kg and 1.5-3.0 μg/kg, respectively. The recoveries varied from 75.1 to 97.2%, with the intra-day and inter-day precisions ≤ 14.2%. Furthermore, the enrichment of the analytes and the clean-up of fat and protein interferences were achieved simultaneously with one-step g-C₃N₄-based MSPE. The present method was convenient, fast, and sensitive, and therefore could be successfully applied for the determination of estrogens in milk powders. Graphical abstract.

and Salmonella in Milk Powder Manufacturing Facilities in the United States

ABSTRACT

The U.S. Food and Drug Administration (FDA) conducted a sampling assignment in 2014 to ascertain the prevalence of Cronobacter spp. and Salmonella in the processing environment of facilities manufacturing milk powder. Cronobacter was detected in the environment of 38 (69%) of 55 facilities. The average prevalence of Cronobacter in 5,671 subsamples (i.e., swabs and sponges from different facility locations) was 4.4%. In the 38 facilities where Cronobacter was detected, the average prevalence of positive environmental subsamples was 6.25%. In 20 facilities where zone information of the sampling location was complete, Cronobacter was most frequently detected in zone 4, followed by zone 3, then zone 2, with zone 1 yielding the lowest percentage of positive samples. The prevalence of Cronobacter across the zones was statistically different (P < 0.05). There was no significant association between product type (i.e., lactose, whey products, buttermilk powder, and nonfat dried milk) and prevalence of Cronobacter in the facility. Salmonella was detected in the environment of three (5.5%) of the 55 facilities; all three facilities produced dried whey product. The overall prevalence of Salmonella in 5,714 subsamples was 0.16%. In facilities in which Salmonella was detected, the average prevalence was 2.5%. Salmonella was most frequently detected in zone 4, followed by zone 3. Salmonella was not detected in zone 1 or zone 2. The disparity between Salmonella and Cronobacter prevalence indicates that additional measures may be required to reduce or eliminate Cronobacter from the processing environment.

HIGHLIGHTS

Temporal dynamics of the fecal microbiota in veal calves in a 6-month field trial

BACKGROUND

Little is known about maturation of calves' gut microbiome in veal farms, in which animals are confined under intensive-farming conditions and the administration of collective antibiotic treatment in feed is common. We conducted a field study on 45 calves starting seven days after their arrival in three veal farms. We collected monthly fecal samples over six months and performed 16S rRNA gene sequencing and quantitative PCR of Escherichia coli to follow the dynamics of their microbiota, including that of their commensal E. coli populations. We used mixed-effect models to characterize the dynamics of α-diversity indices and numbers of E. coli, and searched for an effect of collective antibiotic treatments on the estimated parameters. On two farms, we also searched for associations between recommended daily doses of milk powder and bacterial abundance.

RESULTS

There was high heterogeneity between calves' microbiota upon their arrival at the farms, followed by an increase in similarity, starting at the first month. From the second month, 16 genera were detected at each sampling in all calves, representing 67.5% (± 9.9) of their microbiota. Shannon diversity index showed a two-phase increase, an inflection occurring at the end of the first month. Calves receiving antibiotics had a lower intercept estimate for Shannon index (- 0.17 CI95%[-0.27; - -0.06], p = 0.003) and a smaller number of E. coli/ gram of feces during the treatment and in the 15 days following it (- 0.37 log10 (E. coli/g) CI95%[- 0.66; - 0.08], p = 0.01) than unexposed calves. There were moderate to strong positive associations between the dose of milk powder and the relative abundances of the genera Megasphaera, Enterococcus, Dialister and Mitsuokella, and the number of E. coli (rs ≥ 0.40; Bonferroni corrected p < 0.05).

CONCLUSIONS

This observational study shows early convergence of the developing microbiota between veal calves and associations between the dose of milk powder and members of their microbiota. It suggests that administration of collective antibiotic treatment results in a reduction of microbial diversity and size of the E. coli population and highlights the need for additional work to fully understand the impact of antibiotic treatment in the veal industry.

Fractal analysis of the microstructure of milk powders produced at various temperatures

The quality of milk powder is largely determined during it manufacture process by the morphological characteristics of powder particles. Considering that, the main research objective of this study was to determine whether parameters of the production process contribute to differences in the microstructure of the manufactured powders, and by this means affect their functional traits. To diversify the milk powder production process, various temperatures of the inlet air were used during drying, i.e. 140, 150 and 160 °C. An image fractal analysis was employed and powder particle sizes were compared with respective results achieved in the instrumental analysis using the laser diffraction method. Values of fractal dimensions decreased slightly along with drying temperature increase, what demonstrates that the technological parameters are reflected in the microstructure of milk powders produced. Although particle sizes determined with both methods fitted within the same range of values, the contribution of particular fractions slightly differed and the choice of the appropriate approach may not always be unambiguous. Finally, the fractal dimension is a precise parameter which provides the accurate and explicit characteristics of milk powder microstructure and as such should be recommended for the characterization of irregular structures of different food products.

The effect of phosphate on the heat resistance of spores of dairy isolates of Geobacillus stearothermophilus

In this study, we show that phosphate decreases the spore heat resistance by accelerating the rate of loss of cations from spores. Heat resistance of spores of Geobacillus stearothermophilus A1, D1, P3 and ATCC 12980 were determined in distilled water containing varying concentrations (0.1, 1 and 2% w/v) of di‑sodium phosphate. The average decimal reduction times (D value) for strains A1, D1, P3 and ATCC 12980 in distilled water were 5.8, 6.8, 5.7 and 9 min at 110 °C respectively. On the addition of 0.1, 1 and 2% w/v of di‑sodium phosphate, the average D₁₁₀ values of all the strains in distilled water were lowered by 50, 61 and 70% respectively. Addition of 0.05% w/v of Na-EDTA to distilled water resulted in lowering of the average D₁₁₀ value of all the strains by 55%. Heat resistance of spores of A1, D1, P3 and ATCC 12980 was found to be associated with the Dipicolinic Acid (DPA) content whose concentrations were 0.25, 0.30, 0.27 and 1.6 pg per spore respectively. Analysis by atomic absorption spectroscopy revealed that the phosphate present in the heating medium causes excess release of calcium from spores with 2% w/v phosphate being highly effective, thus confirming the chelating effect of phosphate. This study provides insight into the heat resistance and the increased heat sensitivity of spores of G. stearothermophilus A1, D1 and P3 in the presence of phosphate, which can be used in the design of Cleaning in Place (CIP) systems involving phosphate based cleaning agents to combat biofilms and spores in the dairy industry.

Polycyclic aromatic hydrocarbons in infant formulae, follow-on formulae, and baby foods in Iran: An assessment of risk

Twenty-seven samples of infant formulae and follow-on formulae and fifteen samples of baby food from Iranian markets were analyzed for concentrations of four polycyclic aromatic hydrocarbons (PAH4) determined by use of gas chromatography coupled to mass spectrophotometry. An assessment of risks posed to infants and toddlers was conducted by calculating the margin of exposure and incremental lifetime cancer risk (ILCR) by use of the Monte Carlo Simulation Method. Benzo (a) anthracene, was not detected in any of the samples, while approximately 64.3% samples contained detectable amounts of benzo (a) pyrene, while chrysene was observed in three samples and benzo (b) fluoranthene was detected in one sample. One of the samples contained 1.43 μg PAH4/kg, which was greater than the maximum tolerable limit (MTL; 1 μg/kg) stated in Commission Regulation (EU) 2015/1125. Accordingly, the 95% ILCRs in the infants/toddlers due to ingestion of milk powder and baby foods were determined to be 1.3 × 10^-6 and 7.3 × 10^-7, respectively. Also, the 95th centiles of the MOEs, due to ingesting milk powder or baby foods by infants/toddlers were estimated to be 3.6 × 10⁴ and 7.2 × 10⁴, respectively. In Iran, infants and toddlers are not at serious health risk (MOE ≥ 1 × 10⁴ and ILCR < 1 × 10^-4).

Evaluation of Cronobacter sakazakii inactivation and physicochemical property changes of non-fat dry milk powder by cold atmospheric plasma

Cronobacter sakazakii can cause life-threatening infections in neonates. Exposure to contaminated powdered food, especially milk powder, is a major route for C. sakazakii infection. Cold atmospheric plasma (CAP) is well known as a non-thermal method for inactivating microbial pathogens. This study evaluates the effectiveness of CAP on C. sakazakii in non-fat dry milk (NFDM) powder using a fluidized reaction system. The CAP treatments for 20-120 s led to 1.17-3.27 log₁₀ reductions of C. sakazakii. C. sakazakii inactivation increased with increasing flow rate from 8 to 20 L/min. In terms of quality attributes of NFDM after the CAP treatments, no noticeable color changes (ΔE < 1.5) were observed. Moreover, no significant changes in crystallinity, amino acid composition, or phenolic content occurred following a 120s-CAP treatment. These results indicate that this fluidized reaction system combined with CAP can provide an effective antimicrobial activity with minimal effects on some physicochemical properties of NFDM powder.

Rheological properties of fresh and reconstituted milk protein concentrates under standard and processing conditions

As the processability of fresh and reconstituted milk protein concentrates crucially depends on their rheological properties, a considerable amount of studies focuses on this topic. By means of a direct comparison, we are the first to clearly show that distinct rheological differences can exist between fresh and reconstituted milk protein concentrates under standard and processing conditions. We show that reconstituted milk protein concentrates made from commercial milk protein powders exhibit higher viscosities than fresh ones. Furthermore, we found that during intense shearing, the reconstituted milk protein concentrates undergo a loss of structure, which manifests itself in a significant viscosity decrease. The inverse effect can be observed for fresh milk protein concentrates. Besides these differences, the reconstituted milk protein concentrates exhibit gel-like properties above a certain protein content. We attribute these observations to protein-protein interactions in the milk protein powder, which are induced by manufacturing and/or storing conditions. Our results demonstrate that rheological properties of fresh and reconstituted milk protein concentrates are quantitatively not invariably interchangeable. Thus, the purpose of this article is to emphasize the necessity for researchers and engineers to take into account the rheological particularities of different milk protein concentrates prior to usage.

Method optimization for heavy metal determination in milk powder: application to milk samples from Greece

The scope of this study was the development, optimization and validation of an analytical method for the determination of selected heavy metals and trace elements (As, Hg, Se, Cd, Cu, Pb, Mn, Fe, Ni, Zn, Cr) in milk powder, using microwave-assisted digestion. A statistical experimental design approach using central composite design (CCD) was carried out, to investigate the effects of three independent pretreatment variables (final digestion temperature (°C), HNO₃ concentration (in % w/v), microwave hold time) on the heavy metal recovery of spiked undigested milk powder sample and to calculate the variable factor values which produce the optimum recovery. CCD results revealed that the optimum digestion conditions, with respect to maximum recovery were as follows: temperature 190 °C, HNO₃ 56.8% w/v, and digestion time of 8.47 min. The method was fully validated. Recoveries for all metals ranged between 92 and 108% while intra-day repeatability was below 6.59% (rsd). A certified reference material (ERM BD 150) that included 8 out of the total 11 heavy metals of the present study (Hg, Se, Cd, Cu, Pb, Mn, Ni, and Zn) was used to test the accuracy of the method where acceptable recovery values ranging between 96 and 107% were obtained. High heavy metal recoveries, short digestion time, and low acid consumption were the advantages of the pretreatment method. The analytical process was successfully applied for the determination of heavy metals in different milk samples from the Greek market. Heavy metal concentrations for Ni, Cr, Pb, Cd, Se, Mn, and Cu measured in this study reached 307, 102, 8.01, 5.96, 60.2, 519, and 438 μg/kg wet weight (ww), respectively. Zn and Fe were found at concentrations ranging 3.21-8.39 and 0.170-10.1 mg/kg ww, respectively. Risk assessment based on the WHO tolerable daily intake levels and the calculated target hazard quotients revealed that the consumption of the selected milk samples is considered safe.

Heavy metal content and element analysis of infant formula and milk powder samples purchased on the Tanzanian market: International branded versus black market products

Milk powder is a food for malnourished African children and for healthy infants of women with HIV/AIDS. High demand and low purchasing power has resulted in a huge informal, black market in Sub-Saharan Africa. Forty-three milk powder batches were analyzed for 43 chemical elements using ICP-MS One sample (2.3%) was contaminated at a lead concentration of 240 µg/kg dry weight exceeding the European threshold (130 µg/kg dry weight). Macroelement contents revealed a trend decreasing in concentration through skimmed, full cream products to infant formulae. Concentration ranges by dry weight differed in respect of uncertainty intervals of  ±10%. Median Ca, K and P concentrations declined from 11.14 g/kg to 3.21 g/kg, 14.11 g/kg to 4.95 g/kg and 9.12 g/kg to 2.75 g/kg dry mass, respectively. Milk powder samples obtained from the Tanzanian black market were comparable in respect of nutritional and chemical content to international branded full cream products.

Physical characterization of whole and skim dried milk powders

The lack of updated knowledge about the physical properties of milk powders aimed us to evaluate selected physical properties (water activity, particle size, density, flowability, solubility and colour) of eleven skim and whole milk powders produced in Europe. These physical properties are crucial both for the management of milk powder during the final steps of the drying process, and for their use as food ingredients. In general, except for the values of water activity, the physical properties of skim and whole milk powders are very different. Particle sizes of the spray-dried skim milk powders, measured as volume and surface mean diameter were significantly lower than that of the whole milk powders, while the roller dried sample showed the largest particle size. For all the samples the size distribution was quite narrow, with a span value less than 2. The loose density of skim milk powders was significantly higher than whole milk powders (541.36 vs 449.75 kg/m³). Flowability, measured by Hausner ratio and Carr's index indicators, ranged from passable to poor when evaluated according to pharmaceutical criteria. The insolubility index of the spray-dried skim and whole milk powders, measured as weight of the sediment (from 0.5 to 34.8 mg), allowed a good discrimination of the samples. Colour analysis underlined the relevant contribution of fat content and particle size, resulted in higher lightness (L*) for skim milk powder than whole milk powder, which, on the other hand, showed higher yellowness (b*) and lower greenness (-a*). In conclusion a detailed knowledge of functional properties of milk powders may allow the dairy to tailor the products to the user and help the food processor to perform a targeted choice according to the intended use.

Polycyclic aromatic hydrocarbons in milk powders marketed in Uruguay

Polycyclic aromatic hydrocarbons (PAHs) occurrence in forty-four samples of milk powder, marketed in Uruguay, was determined. A high-performance liquid chromatography (HPLC) method was applied with fluorescence detector (FLD) and UV-VIS diodes array detector (DAD). Milk powder was fortified with PAHs at three levels producing average recovery higher than 78.6% for all levels. The highest concentration of benzo(a)pyrene (BaP) was 2.85 μg kg^-1 in milk powder. Contamination of samples expressed as the sum of 16 analysed PAHs varied between 5.77 and 427.28 μg kg^-1 and as PAH4 (BaP, chrysene, benzo(a)anthracene and benzo(b)fluoranthene) was between below LOD and 11.54 μg kg^-1. Only one sample exceeded the maximum limit for BaP, but 84% of the commercial milk powders did not comply with the European Union maximum limit for PAH4.

Detection of Mycobacterium avium subspecies paratuberculosis in powdered infant formula using IS900 quantitative PCR and liquid culture media

Mycobacterium avium subspecies paratuberculosis (MAP) has been implicated in Crohn's disease in humans resulting in public concern over the presence of MAP in powdered infant formula, which could contribute towards early human exposure to MAP or MAP components. Testing of representative powdered infant formula samples using effective tests is required to provide information on contamination of infant formula with MAP, so that consumers can make informed decisions. This study aimed to test representative powdered infant formula samples for the presence of MAP using a quantitative PCR and liquid culture method. For this purpose, an efficient DNA extraction method was developed and an optimum decontamination protocol for culture method was identified. A total of 122 powdered infant formula samples were tested, comprising 72 brands produced by 12 manufacturers from 9 countries. Powdered infant formula samples were reconstituted and centrifuged to separate the casein pellet, cream layer and whey fraction. A sensitive qPCR test was performed on DNA extracted from the casein pellet. In addition, the cream layer and casein pellet were cultured in liquid media, following decontamination with the optimum protocol. Of the 122 samples tested, 6 were positive for MAP DNA but none were positive for growth in culture at 12 and 20 weeks. The limit of detection of the quantitative PCR was less than 5 MAP organisms per 1.5g milk powder. The methods developed in the study could be used for quality assurance testing for infant formula and calf milk replacers. The low contamination level of MAP and absence of viable forms in our study suggests a relatively low risk of exposure of infants to MAP components.

Environmental impacts of milk powder and butter manufactured in the Republic of Ireland

The abolition of the milk quota system that was in place in Europe was abolished in 2015, which instigated an immediate increase in milk production in many European countries. This increase will aid in addressing the world's ever growing demand for food, but will incur increased stresses on the environmental impact and sustainability of the dairy industry. In this study, an environmental life cycle assessment was performed in order to estimate the environmental impacts associated with the manufacture of milk powder and butter in the Republic of Ireland. A farm gate to processing factory gate analysis, which includes raw milk transportation, processing into each product and packaging, is assessed in this study. Operational data was obtained from 5 dairy processing factories that produce milk powder (4 of which also produce butter). Results for each environmental impact category are presented per kilogram of product. Energy consumption (raw milk transportation and on-site electrical and thermal energy usage) contributes, on average, 89% and 78% of the total global warming potential, for milk powder and butter respectively, for the life cycle stages assessed. Similarly, energy consumption contributes, on average, 86% and 96% of the total terrestrial acidification potential for milk powder and butter respectively, for these life cycle stages. Emissions associated with wastewater treatment contribute approximately 10% and 40% to the total freshwater eutrophication potential and marine eutrophication potential, respectively, for both milk powder and butter production. In addition, packaging materials also has a significant contribution to these environmental impact categories for butter production. Results were also presented for three milk powder products being manufactured by the factories surveyed: skim milk powder, whole milk powder and full fat milk powder. The analysis presented in this paper helps to identify opportunities to reduce the environmental impacts associated with post-farm processing of milk powder and butter.

Time resolved fluorescence of cow and goat milk powder

Milk powder is an international dairy commodity. Goat and cow milk powders are significant sources of nutrients and the investigation of the authenticity and classification of milk powder is particularly important. The use of time-resolved fluorescence techniques to distinguish chemical composition and structure modifications could assist develop a portable and non-destructive methodology to perform milk powder classification and determine composition. This study goal is to differentiate milk powder samples from cows and goats using fluorescence lifetimes. The samples were excited at 315nm and the fluorescence intensity decay registered at 468nm. We observed fluorescence lifetimes of 1.5±0.3, 6.4±0.4 and 18.7±2.5ns for goat milk powder; and 1.7±0.3, 6.9±0.2 and 29.9±1.6ns for cow's milk powder. We discriminate goat and cow powder milk by analysis of variance using Fisher's method. In addition, we employed quadratic discriminant analysis to differentiate the milk samples with accuracy of 100%. Our results suggest that time-resolved fluorescence can provide a new method to the analysis of powder milk and its composition.

Determination of whey adulteration in milk powder by using laser induced breakdown spectroscopy

A rapid and in situ method has been developed to detect and quantify adulterated milk powder through adding whey powder by using laser induced breakdown spectroscopy (LIBS). The methodology is based on elemental composition differences between milk and whey products. Milk powder, sweet and acid whey powders were produced as standard samples, and milk powder was adulterated with whey powders. Based on LIBS spectra of standard samples and commercial products, species was identified using principle component analysis (PCA) method, and discrimination rate of milk and whey powders was found as 80.5%. Calibration curves were obtained with partial least squares regression (PLS). Correlation coefficient (R(2)) and limit of detection (LOD) values were 0.981 and 1.55% for adulteration with sweet whey powder, and 0.985 and 0.55% for adulteration with acid whey powder, respectively. The results were found to be consistent with the data from inductively coupled plasma - mass spectrometer (ICP-MS) method.

Microwave-assisted wet digestion with H2O2 at high temperature and pressure using single reaction chamber for elemental determination in milk powder by ICP-OES and ICP-MS

In this work a green digestion method which only used H2O2 as an oxidant and high temperature and pressure in the single reaction chamber system (SRC-UltraWave™) was applied for subsequent elemental determination by inductively coupled plasma-based techniques. Milk powder was chosen to demonstrate the feasibility and advantages of the proposed method. Samples masses up to 500mg were efficiently digested, and the determination of Ca, Fe, K, Mg and Na was performed by inductively coupled plasma optical emission spectrometry (ICP-OES), while trace elements (B, Ba, Cd, Cu, Mn, Mo, Pb, Sr and Zn) were determined by inductively coupled plasma mass spectrometry (ICP-MS). Residual carbon (RC) lower than 918mgL(-1) of C was obtained for digests which contributed to minimizing interferences in determination by ICP-OES and ICP-MS. Accuracy was evaluated using certified reference materials NIST 1549 (non-fat milk powder certified reference material) and NIST 8435 (whole milk powder reference material). The results obtained by the proposed method were in agreement with the certified reference values (t-test, 95% confidence level). In addition, no significant difference was observed between results obtained by the proposed method and conventional wet digestion using concentrated HNO3. As digestion was performed without using any kind of acid, the characteristics of final digests were in agreement with green chemistry principles when compared to digests obtained using conventional wet digestion method with concentrated HNO3. Additionally, H2O2 digests were more suitable for subsequent analysis by ICP-based techniques due to of water being the main product of organic matrix oxidation. The proposed method was suitable for quality control of major components and trace elements present in milk powder in consonance with green sample preparation.

The impact of atomization on the surface composition of spray-dried milk droplets

The dominant presence of fat at the surface of spray-dried milk powders has been widely reported in the literature and described as resulting in unfavourable powder properties. The mechanism(s) causing this phenomenon are yet to be clearly identified. A systematic investigation of the component distribution in atomized droplets and spray-dried particles consisting of model milk systems with different fat contents demonstrated that atomization strongly influences the final surface composition. Cryogenic flash-freezing of uniform droplets from a microfluidic jet nozzle directly after atomization helped to distinguish the influence of the atomization stage from the drying stage. It was confirmed that the overrepresentation of fat on the surface is independent of the atomization technique, including a pressure-swirl single-fluid spray nozzle and a pilot-scale rotary disk spray dryer commonly used in industry. It is proposed that during the atomization stage a disintegration mechanism along the oil-water interface of the fat globules causes the surface predominance of fat. X-ray photoelectron spectroscopic measurements detected the outermost fat layer and some adjacent protein present on both atomized droplets and spray-dried particles. Confocal laser scanning microscopy gave a qualitative insight into the protein and fat distribution throughout the cross-sections, and confirmed the presence of a fat film along the particle surface. The film remained on the surface in the subsequent drying stage, while protein accumulated underneath, driven by diffusion. The results demonstrated that atomization induces component segregation and fat-rich surfaces in spray-dried milk powders, and thus these cannot be prevented by adjusting the spray drying conditions.

Leaf concentrate compared with skimmed milk as nutritional supplementation for HIV-infected children: a randomized controlled trial in Burundi

OBJECTIVE

The effectiveness of leaf concentrate powder (LCP) as a nutritional supplement was established in trials conducted among adolescent girls and pregnant women in India. Here we evaluate LCP, compared with skimmed milk powder (SMP), as a supplement for antiretroviral-naïve children living with HIV in a sub-Saharan African country.

DESIGN

Randomized controlled, two-arm, 6-month trial comparing effects of isoproteic (5 g) LCP (10 g daily) and SMP (15 g daily) on HIV-1 viral load, CD4+ cell count/percentage, weight/height-for-age, general blood parameters, diarrhoea, respiratory and HIV-related opportunistic infections.

SETTING

Bujumbura and Kirundo, Burundi.

SUBJECTS

Eighty-three HIV-positive, antiretroviral-naïve children aged 5-14 years: median (range) CD4+ count, 716 (361-1690) cells/mm3; log10 HIV-1 viral load, 4·39 (1·79-6·00).

RESULTS

LCP was equivalent to SMP in relation to HIV-specific blood parameters and did not demonstrate superiority over SMP in relation to Hb. Three children in each arm (LCP, 7·1 % (3/42); SMP, 7·3 % (3/41)) proceeded to antiretroviral therapy because their CD4+ counts fell below 350 cells/mm3. Children in the LCP group reported higher levels of appetite and overall health at 6 months. There were no differences in clinical events or any other outcome measures. LCP was less palatable than SMP to the children in this population, but there were few negative perceptions of appearance, texture and taste.

CONCLUSIONS

LCP appears to be equivalent to SMP as a nutritional supplement in this population, despite slightly lower palatability. In relation to viral load and CD4+ count, equivalence may indicate no effect in either group. Effectiveness relative to no supplementation remains to be determined.

Rapid detection of whey in milk powder samples by spectrophotometric and multivariate calibration

A rapid method for the detection and quantification of the adulteration of milk powder by the addition of whey was assessed by measuring glycomacropeptide protein using mid-infrared spectroscopy (MIR). Fluid milk samples were dried and then spiked with different concentrations of GMP and whey. Calibration models were developed using multivariate techniques, from spectral data. For the principal component analysis and discriminant analysis, excellent percentages of correct classification were achieved in accordance with the increase in the proportion of whey samples. For partial least squares regression analysis, the correlation coefficient (r) and root mean square error of prediction (RMSEP) in the best model were 0.9885 and 1.17, respectively. The rapid analysis, low cost monitoring and high throughput number of samples tested per unit time indicate that MIR spectroscopy may hold potential as a rapid and reliable method for detecting milk powder frauds using cheese whey.

Rapid screening of mycotoxins in liquid milk and milk powder by automated size-exclusion SPE-UPLC-MS/MS and quantification of matrix effects over the whole chromatographic run

An automated, size-exclusion solid phase extraction (SPE)-UPLC-MS/MS protocol without pre-treatment of samples was developed to screen for four mycotoxins (OTA, ZEN, AFB1, and AFM1) in liquid milk and milk powder. Firstly, a mixed macropore-silica gel cartridge was established as a size-exclusion SPE column. The proposed methodology could be a candidate in green analytical chemistry because it saves on manpower and organic solvent. Permanent post-column infusion of mycotoxin standards was used to quantify matrix effects throughout the chromatographic run. Matrix-matched calibration could effectively compensate for matrix effects, which may be caused by liquid milk or milk powder matrix. Recovery of the four mycotoxins in fortified liquid milk was in the range 89-120% and RSD 2-9%. The LOD for the four mycotoxins in liquid milk and milk powder were 0.05-2 ng L(-1) and 0.25-10 ng kg(-1), respectively. The LOQ for the four mycotoxins in liquid milk and milk powder were 0.1-5 ng L(-1) and 0.5-25 ng kg(-1), respectively.

Development of a Multiplex-PCR assay for the rapid identification of Geobacillus stearothermophilus and Anoxybacillus flavithermus

The presence of thermophilic bacilli in dairy products is indicator of poor hygiene. Their rapid detection and identification is fundamental to improve the industrial reactivity in the implementation of corrective and preventive actions. In this study a rapid and reliable identification of Geobacillus stearothermophilus and Anoxybacillus flavithermus was achieved by species-specific PCR assays. Two primer sets, targeting the ITS 16S-23S rRNA region and the rpoB gene sequence of the target species respectively, were employed. Species-specificity of both primer sets was evaluated by using 53 reference strains of DSMZ collection; among them, 13 species of the genus Geobacillus and 15 of the genus Anoxybacillus were represented. Moreover, 99 wild strains and 23 bulk cells collected from 24 infant formula powders gathered from several countries worldwide were included in the analyses. Both primer sets were highly specific and the expected PCR fragments were obtained only when DNA from G. stearothermophilus or A. flavithermus was used. After testing their specificity, they were combined in a Multiplex-PCR assay for the simultaneous identification of the two target species. The specificity of the Multiplex-PCR was evaluated by using both wild strains and bulk cells. Every analysis confirmed the reliable identification results provided by the single species-specific PCR methodology. The easiness, the rapidity (about 4 h from DNA isolation to results) and the reliability of the PCR procedures developed in this study highlight the advantage of their application for the specific detection and identification of the thermophilic species G. stearothermophilus and A. flavithermus.

Determination of flavor enhancers in milk powder by one-step sample preparation and two-dimensional liquid chromatography

Maltol, ethyl maltol, vanillin, and ethyl vanillin are important food additives as flavor enhancers. To quantify the four additives in milk powder, a novel 2D liquid chromatographic (2DLC) method was developed in this article. In such a 2DLC system, the target fractions eluted from the first dimensional column (C4) are stored onto the trapping column (C8) for subsequent analysis; after that, they were switched into the second dimensional column (C18) by a two-position six-port switching valve. A one-step sample preparation method was used prior to 2DLC chromatographic analysis, which was easy and convenient. After optimization of all experimental parameters, the new method was validated in terms of linearity, LODs, and LOQs, intra- and interday precision, and accuracy. A conventional single-dimensional liquid chromatographic method was also proposed in this work for comparison. In order to evaluate the applicability of the new 2DLC method, five brands of commercial milk powder samples (n = 8) were analyzed. Vanillin and ethyl vanillin were detected in two samples, respectively. It is showed that the 2DLC method is effective in quality control programs of milk powder products.

Fast determination of myo-inositol in milk powder by ultra high performance liquid chromatography coupled to tandem mass spectrometry

A simple and fast method has been developed and validated for the determination of myo-inositol in milk powder samples, using solid-liquid extraction with water (0.01% formic acid, v/v):methanol (1:1, v/v). The determination was carried out by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) using an electrospray ionisation source (ESI) in positive mode. Chromatographic separation was carried out using as mobile phase water (0.01% formic acid, v/v) and methanol in gradient mode. Data acquisition under MS/MS was achieved by applying selected reaction monitoring, using 181.0→109.0 and 181.0→81.0 for quantification and confirmation purposes, respectively. The technique provides a sensitive and selective determination of myo-inositol in the analysed samples, with a run time of 4min. The limit of detection and quantification were 0.2 and 0.5mgkg(-1), respectively. The method was applied to six fortified commercial milk powder samples containing myo-inositol amounts ranging from 290 to 2200mgkg(-1).