Whole Milk Powder Research Articles

Determination of Nitrite in Milk- and Soy-Based Nutritional Ingredients by Derivatization with 2,3-Diaminonaphthalene and Fluorescence Spectrometry.

Nitrite (NO2-) is an inorganic anion that can be found in various powdered milk- and soy-based nutritional ingredients as an incidental contaminant. Reliable determination of NO2- in nutritional ingredients is of paramount importance to ensure the safety of finished products. The derivatization reaction of NO2- with 2,3-diaminonaphthalene with the formation of fluorescent 2,3-naphtotriazole has been adapted to milk- and soy-based nutritional ingredients. The sample preparation consisted of protein precipitation with Carrez solution, simple pass-through cleanup of extracts utilizing a carbon black-based cartridge and derivatization, followed by batch fluorometry. The method was validated in six representative ingredient matrixes-i.e., whole-milk powder, nonfat dry milk, milk protein concentrate, whey protein concentrate, sodium caseinate, and soy protein isolate. Recovery values were 82-109%, whereas within-day and intermediate precision were 0.6-5.2 and 3.6-11% (RSDs), respectively. The method LOQ was 0.1 or 0.2 µg/g sodium nitrite (NaNO2), depending on the ingredient matrix. Surveyed NO2- concentration levels in 25 lots of 10 types of nutritional ingredients ranged from between less than 0.1 to 29 µg/g NaNO2. This method is proposed as a more sensitive and rugged alternative to the widely used ion chromatographic and colorimetric approaches.

Rheological, sensory, and microstructural properties of fresh and frozen/thawed mashed potatoes enriched with different proteins

ABSTRACTIn this study, the effect of the addition of soybean protein isolate (SPI), whey protein isolate (WPI), whole milk powder (WMP), and sodium caseinate (SC) on the rheological, physical, sensory, and structural properties of fresh and frozen/thawed mashed potatoes formulated with added cryoprotectants [kappa-carrageenan (κ-C) and xanthan gum (XG)] was compared. Steady shear flow rate curves indicated a non-Newtonian fluid and exhibited typical shear thinning (pseudoplastic) behavior (n < 1) with all added proteins. The results showed that there is no significant change in the apparent viscosity (ηapp) of fresh mashed potatoes (FMP) and frozen/thawed mashed potatoes (F/TMP) with added WMP and SC at a concentration of 5 g/kg. While the addition of SPI at a concentration of 10 g/kg increased the ηapp and pseudoplasticity, which indicates that the SPI behaves as harder fillers. Based on the sensory evaluation results, WPI and WMP could incorporate to FMP without losing the sensory quality of the product. F/TMP samples with addition of SPI were judged more acceptable than other processed samples, evidencing the ability of this protein to reduce the influence of freeze/thaw process.

The effect of homogenization pressure on the flavor and flavor stability of whole milk powder

Flavor is one of the key factors that can limit the application and shelf life of dried dairy ingredients. Many off-flavors are caused during ingredient manufacture that carry through into ingredient applications and decrease consumer acceptance. The objective of this research was to investigate the effect of homogenization pressure on the flavor and flavor stability of whole milk powder (WMP). Whole milk powder was produced from standardized pasteurized whole milk that was evaporated to 50% solids (wt/wt), homogenized in 2 stages with varying pressures (0/0, 5.5/1.4, 11.0/2.8, or 16.5/4.3 MPa), and spray dried. Whole milk powder was evaluated at 0, 3, and 6 mo of storage at 21°C. Sensory properties were evaluated by descriptive analysis. Volatile compounds were analyzed by sorptive stir bar extraction with gas chromatography-mass spectrometry. Fat globule size in condensed whole milk and particle size of powders were measured by laser diffraction. Surface free fat, inner free fat, and encapsulated fat of WMP were measured by solvent extractions. Phospholipid content was measured by ultra-high-performance liquid chromatography-evaporative light scattering. Furosine in WMP was analyzed by ultra-high-performance liquid chromatography-mass spectrometry. Increased homogenization pressure decreased cardboard and painty flavors, volatile lipid oxidation compound concentrations, fat globule size in condensed milk, surface free fat, and inner free fat in WMP. Encapsulated fat increased and phospholipid-to-encapsulated fat ratio decreased with higher homogenization pressure. Surface free fat in powders increased cardboard flavor and lipid oxidation. These results indicate that off-flavors were decreased with increased homogenization pressures in WMP due to the decrease in free fat. To decrease off-flavor intensities in WMP, manufacturers should carefully evaluate these parameters during ingredient manufacture.

Dairy product production and lactose demand in New Zealand and Ireland under different simulated milk product-processing portfolios

Abstract Maximising dairy industry profitability involves maximising product returns for a specific set of costs or minimising costs for a certain level of output. A strategy currently utilised by the New Zealand dairy industry to optimise the value of exports is to incorporate imported lactose along with local milk to maximise the production of whole milk powder (WMP) while complying with the Codex Alimentarius (Codex) standards, in addition to increasing the exported product for every litre of milk. This study investigated the impact of different product portfolio strategies on lactose requirements for the Irish and New Zealand dairy industries for current and predicted 2020 milk output projections. A mass balance processing sector model that accounts for all inputs, outputs and losses involved in dairy processing was used to simulate the processing of milk into WMP, skim milk powder (SMP), cheese, butter and fluid milk of different proportions. All scenarios investigated projected an increase in production and revenue from 2012 to 2020. Higher cheese production reduced industry lactose demand through whey processing, while scenarios reliant on an increase in the proportion of WMP were associated with increased lactose deficits.

Studies on physico-chemical properties of whole milk powdermanufactured or sold in Maharashtra, India

Twenty-five samples of spray dried whole milk powder (WMP) of different brands were procured from five regions of Maharashtra namely Vidarbha, North Maharashtra, Western Maharashtra, Marathwada and Mumbai. These samples were analyzed for the chemical composition, physico-chemical properties and microbiological quality to access their suitability in terms of national and international standards. The moisture, fat and protein content in WMP obtained from different regions varied significantly.Wide variation in the physical properties like scorched particles, wettability, dispersibility and solubility index was observed in WMP. The NPN, true protein content, titratable acidity and lactate content and free fat content of WMP samples were varied significantly. The standard plate count and coliform count of WMP samples were lower than that of the standard prescribed by BIS and PFA. In the present study except few, all the samples meet the requirements of national and international standards.

Grau de Concorrência e Poder de Mercado nas Exportações de Leite em Pó para o Brasil

Resumo: Há indícios de que Argentina e Uruguai atuem como oligopolistas e exerçam poder de mercado nas exportações de leite em pó para o Brasil. As firmas dos dois países supracitados exportam quase a totalidade destes derivados para o território brasileiro, ao passo que há uma regionalização do comércio internacional destes produtos, restringindo a concorrência com outros países. O objetivo central do presente trabalho é verificar o grau de concorrência nas exportações de leite em pó integral e desnatado para o Brasil pela existência do poder de mercado praticado pelos países exportadores. Para isto, utiliza-se o modelo de demanda residual, estimado por mínimo quadrado de dois estágios (MQ2E), seemingly unrelated regressions (SUR) e mínimo quadrado de três estágios (MQ3E). Os resultados indicam que o Uruguai atua como oligopolista e exerce poder de mercado em ambos os mercados, enquanto a Argentina, apenas no caso do leite em pó integral. Os resultados sugerem que o Brasil deve buscar meios de elevar a concorrência nas importações de leite em pó, já que, assim, os preços tenderiam a ser menores e os consumidores se beneficiariam neste aspecto.

Rapid non-invasive quality control of semi-finished products for the food industry by direct injection mass spectrometry headspace analysis: the case of milk powder, whey powder and anhydrous milk fat.

In this study, we demonstrated the suitability of direct injection mass spectrometry headspace analysis for rapid non-invasive quality control of semi-finished dairy ingredients, such as skim milk powder (SMP), whole milk powder (WMP), whey powder (WP) and anhydrous milk fat (AMF), which are widely used as ingredients in the food industry. In this work, for the first time, we applied proton transfer reaction-mass spectrometry (PTR-MS) with a time-of-flight (ToF) analyzer for the rapid and non-invasive analysis of volatile compounds in different samples of SMP, WMP, WP and AMF. We selected different dairy ingredients in various concrete situations (e.g. same producer and different expiration times, different producers and same days of storage, different producers) based on their sensory evaluation. PTR-ToF-MS allowed the separation and characterization of different samples based on the volatile organic compound (VOC) profiles. Statistically significant differences in VOC content were generally coherent with differences in sensory evaluation, particularly for SMP, WMP and WP. The good separation of SMP samples from WMP samples suggested the possible application of PTR-ToF-MS to detect possible cases of adulteration of dairy ingredients for the food industry. Our findings demonstrate the efficient and rapid differentiation of dairy ingredients on the basis of the released VOCs via PTR-ToF-MS analysis and suggest this method as a versatile tool (1) for the facilitation/optimization of the selection of dairy ingredients in the food industry and (2) and for the prompt innovation in the production of dairy ingredients. Copyright © 2016 John Wiley & Sons, Ltd.

Optimization of process parameters for supercritical fluid extraction of cholesterol from whole milk powder using ethanol as co‐solvent

In spite of being highly nutritious, the consumption of milk is hindered because of its high cholesterol content, which is responsible for numerous cardiac diseases. Supercritical carbon dioxide using ethanol as co-solvent was employed to extract cholesterol from whole milk powder (WMP). This study was undertaken to optimize the process parameters of supercritical fluid extraction (SCFE), viz. extraction temperature, pressure and volume of ethanol. The cholesterol content of WMP was quantified using high-performance liquid chromatography. The impact of the extraction conditions on the fat content (FC), solubility index (SI) and lightness (L*) of the SCFE-treated WMP were also investigated. The process parameters were optimized using response surface methodology. About 46% reduction in cholesterol was achieved at the optimized conditions of 48 °C, 17 MPa and 31 mL co-solvent; flow rate of expanded CO2 , static time and dynamic time of extraction were 6 L min-1 , 10 min and 80 min respectively. The treated WMP retained its FC, SI, and L* at moderate limits of 183.67 g kg-1 , 96.3% and 96.90, respectively. This study demonstrated the feasibility of ethanol-modified SCFE of cholesterol from WMP with negligible changes in its physicochemical properties. © 2016 Society of Chemical Industry.

Effects of milk somatic cell counts on some physicochemical and functional characteristics of skim and whole milk powders

The aim of this work was to study the influence of milk somatic cell count (SCC) levels on spray-dried milk powders. For this reason, 3 cow milks with different SCC (<300,000, 300,000–700,000, >700,000 SCC/mL) were processed into skim (SMP) and whole milk powder (WMP). The effect of SCC on the physicochemical and functional characteristics of the milk powders and textural properties of set-type yogurts produced from reconstituted milk powders with different SCC was evaluated. A crucial difference was noted between milk powders depending on different SCC. Protein values and ash content of powder samples decreased correlatively with increasing SCC. The hydroxymethylfurfural content of SMP was higher than WMP. We noted an increase in hydroxymethylfurfural content of both SMP and WMP depending on elevated SCC. Solubility index of SMP and WMP was 1.280 to 1.632 and 0.940 to 1.208mL, respectively; with increasing SCC, solubility index was affected adversely. The highest foam stability was determined in SMP containing >700,000 SCC. Bulk density of SMP and WMP was between 0.682 and 0.708 and 0.660 to 0.685g/cm3, respectively. An increase was observed in scorched particle of both SMP and WMP depending on increasing SCC. We found significant differences in particle size distribution of milk powders produced from milk with SCC at different levels. Although WMP had more uniform and big particle structure, SMP had more specific area. A negative correlation was noted between yogurt texture and SCC. Results indicate that milk SCC has negative influences on milk powder quality.

Effect of whole milk concentrate carbonation on functional, physicochemical and structural properties of the resultant spray dried powder during storage

The effect of carbonation (1000 and 2000 ppm) on whole milk concentrate and the resultant spray dried whole milk powder (WMP) was investigated in this research. Carbonation was found to produce WMP with reduced surface fat content, dispersibility, solubility and true density, and increased occluded air content. During accelerated storage at 37 °C for 18 weeks, the surface coverage of fat on powder particles increased from 51, 29 and 8 to 94, 88 and 69% (WMP without treatment and treated with 1000 ppm and 2000 ppm CO2 respectively) due to the release and spreading of encapsulated fat. In addition to the release of fat onto the surface, microscopy observations showed the migration of free fat into the powder particle vacuoles. Meanwhile, dispersibility and solubility of the powders decreased during storage for 18 weeks. These results suggest that carbonation may result in powders with better shelf life due to the reduced surface fat content. Improvements in functional properties was not observed, possibly due to the fine size of the powders (<15 μm) that may have masked the positive effect of carbonation.

Responses in lactose yield, lactose percentage and protein-to-protein-plus-lactose ratio from index selection in New Zealand dairy cattle

ABSTRACTThe breeding goal of the New Zealand dairy industry is to improve the genetic capability of cows to convert pasture-based feed into farmer profit. The New Zealand dairy industry exports over 95% of milk produced and the most significant product by export volume is whole milk powder (WMP). The current selection objective, breeding worth (BW), will increase yields of protein and fat, potentially shifting milk composition further from the ideal composition for making WMP. This study aimed to investigate the correlated responses in lactose yield (LY), lactose percentage (LP) and protein-to-protein-plus-lactose ratio (P:P + L) from selection for BW, BW plus LY, BW plus LP and BW plus P:P + L. Selection for BW is predicted to have per-cow responses of 54.92 kg milk/year, 2.22 kg fat/year, 1.78 kg protein/year and 2.84 kg lactose/year. When lactose was included in the selection objective in the form of LY, LP or P:P + L, genetic responses ranged from −59.98 kg to 61.08 kg milk/year and from −2.67 kg to 3.70 kg lactose/year. The industry could reduce imported lactose requirements per tonne of WMP by 6%–11% by including lactose into the selection objective, compared with selection on BW alone.

Identification of goat milk powder by manufacturer using multiple chemical parameters

Concentrations of multiple elements and ratios of stable isotopes of carbon and nitrogen were measured and combined to create a chemical fingerprint of production batches of goat whole milk powder (WMP) produced by different manufacturers. Our objectives were to determine whether or not differences exist in the chemical fingerprint among samples of goat WMP produced at different sites, and assess temporal changes in the chemical fingerprint in product manufactured at one site. In total, 58 samples of goat WMP were analyzed by inductively coupled plasma-mass spectrometry as well as isotope ratio mass spectrometry and a suite of 13 elements (Li, Na, Mg, K, Ca, Mn, Cu, Zn, Rb, Sr, Mo, Cs, and Ba), δ13C, and δ15N selected to create the chemical fingerprint. Differences in the chemical fingerprint of samples between sites and over time were assessed using principal components analysis and canonical analysis of principal coordinates. Differences in the chemical fingerprints of samples between production sites provided a classification success rate (leave-one-out classification) of 98.1%, providing a basis for using the approach to test the authenticity of product manufactured at a site. Within one site, the chemical fingerprint of samples produced at the beginning of the production season differed from those produced in the middle and late season, driven predominantly by lower concentrations of Na, Mg, K, Mn, and Rb, and higher concentrations of Ba and Cu. This observed temporal variability highlights the importance of obtaining samples from throughout the season to ensure a representative chemical fingerprint is obtained for goat WMP from a single manufacturing site. The reconstitution and spray drying of samples from one manufacturer by the other manufacturer enabled the relative influence of the manufacturing process on the chemical fingerprint to be examined. It was found that such reprocessing altered the chemical fingerprint, although the degree of alteration varied among samples and individual elements. The findings of this study support the use of trace elements and stable isotope ratios to test the authenticity of goat WMP, which can likely be applied to other dairy goat products. This approach could be used test to the factory of origin (and potentially batch of origin) of products in the supply chain, thus providing the ability to audit the supply chain and monitor for fraudulent activity.

미세캡슐화 마늘분말의 안정성 및 관능특성

The objectives of this study are to encapsulate lyophilized garlic powder with various coating materials for reducing its unpleasant taste and odor and to investigate their physiochemical and taste masking properties. All coating materials used in this study were edible ones such as maltodextrin (MD), whey protein isolate (WPI), whole milk powder (WMP), and skim milk powder (SMP). To produce encapsulated garlic powders, lyophilized garlic powder was mixed with coating materials at the ratio of 1:1 followed by homogenization for 30 min, and then spray- or freezedried. Physiochemical property measurements and quantitative analyses were carried out for the encapsulated garlic powders. Encapsulated garlic powder using WMP with spray drying method showed the highest alliin concentration (4.131 mg/g) compared to those coated with other coating materials. Sensory evaluation showed that encapsulated garlic powder using WPI and WMP reduced unpleasant garlic taste and odor effectively. Milk fats in the WMP and hydrophobic chains of the proteins in WPI might bind with volatile and hydrophobic odor emitting molecules. In the evaluation for aqueous stability, encapsulated garlic powder using WMP showed better stability compared to others. This garlic taste and odor masking study can contribute to a number of possible health benefits by adding garlic powder to a wide variety of functional foods.

Selective fractionation of cholesterol from whole milk powder: optimisation of supercritical process conditions

SummarySupercritical fluid extraction (SCFE) of cholesterol from whole milk powder (WMP) was investigated in this study. The combined effects of temperature (40–80 °C) and pressure (150–250 bar) on the efficacy of cholesterol extraction (mg 100 g−1), modifications in the fat content (FC) (%) and solubility index (SI) (%) of WMP were studied and optimised by the application of response surface methodology (RSM). Variations in the free fatty acids (FFAs) (mg oleic acid per 100 g of milk fat) and lightness value (L*) were also investigated after SCFE process. About 55.8% reduction in cholesterol was achieved at the optimised condition of 68 °C, 207 bar with 40 min static time and 2 h dynamic time at flow rate of 6 L min−1. Extraction at the optimised conditions maximised the yield of cholesterol while retaining the FC, SI, FFA and L* at moderate limits of 23.7%, 85.1%, 7.7 mg per 100 g milk fat and 95.4, respectively.

Reduction in phytic acid content and enhancement of antioxidant properties of nutricereals by processing for developing a fermented baby food.

Cereal blends containing pearl millet (Pennisetum glaucum), sorghum (Sorghum bicolor) and oat (Avena sativa) in different ratios were processed (roasted and germinated) and also used as unprocessed flours followed by fermentation with Lactobacillus sp. (Lactobacillus casei and Lactobacillus plantarum). They were screened for total phenolic content (TPC), phytic acid content (PAC) and free radical scavenging activity (FRSA). A formulation with the highest TPC, FRSA and the lowest PAC was selected to optimize a nutricereal based fermented baby food containing selected fermented cereal blends (FCB), rice-corn cooked flour (RCF), whole milk powder (WMP), whey protein concentrate (WPC) and sugar. The optimized baby food formulation contained 37.41g 100g(-1) FCB, 9.75g 100g(-1) RCF, 27.84g 100g(-1) WMP, 5g 100g(-1) WPC and 20g 100g(-1) sugar. It had high protein, vitamin, minerals, as well as good quantity of carbohydrates and fat, to fulfil the nutritional needs of preschool children of age 1-3years. The nutricereal based fermented baby food showed high water absorption capacity, dispersibility, wettability and flowability indicating good reconstitution properties.

Availability of Detection Frequency Method Using Three-Port Gas Chromatography-Olfactometry for Rapid Comparison of Whole Milk Powders

The purpose of this study was to investigate the common components and characteristic compounds of whole milk powders (WMPs) produced in three different regions of Asia and Oceania. The volatile components were isolated from seven WMPs produced in Japan, New Zealand, and China. Forty-one aroma-active compounds were detected in these volatile components using gas chromatography-olfactometry by the detection frequency method. The binary data converted from the detection frequency values was applied to the principal component analysis (PCA) and hierarchical cluster analysis (HCA). The HCA result showed three clusters corresponding to the production regions. Based on the PCA, approximately 70% of the total variance of WMPs was explained by the PC1 and PC2 scores. The PC1 scores can be used to examine the property of WMPs based on the aroma of dairy products and the PC2 scores indicated the property of the production region based on the scattering plot of each WMP. Based on the PC2 loading values of aroma-active compounds, it was revealed that, depending on the production region, the difference between the whole aromas of different WMPs was caused not by the characteristic compound, but by the balance of aroma impact compounds that commonly occur in WMPs.

Development of a Formulation for Instant Corn Based Dessert Mix Powder and Quality Evaluation: Research Advances

Process for development of instant corn based dessert mix powder was optimized employing full factorial design. Instantization of corn was done using hot air popping method. Popped corn flour (PCF) and whole milk powder (WMP) varied from 26.84 to 37.78 and 42.50 to 53.68 %, respectively in the dessert mix samples. The hedonic scores for appearance, consistency, mouthfeel, taste/flavour and overall acceptability of corn based dessert samples varied from 6.573 to 8.067, 6.458 to 8.175, 6.653 to 8.343, 6.667 to 8.250 and 6.875 to 8.188, respectively. Overall sensory acceptability score was maximum for sample containing 14:24 ratio of PCF:WMP. Sensory characteristics of dessert mix were affected by both the factors and also by the interaction of both factors. Bulk density, water absorption and water solubility index ranged from 0.152 to 0.205 g/mL, 203.71 to 260.67 % and 36.88 to 42.44 %, respectively. Physico-chemical and organoleptic quality characteristics were affected by PCF, WMP and interaction of both factors. Lightness values decreased while peak and final viscosities increased with increasing proportion of corn in dessert mix samples. Protein, fat, minerals, crude fiber, calories, and in vitro protein digestibility for most acceptable sample was 17.34 %, 14.96 %, 3.68 %, 1.1 %, 449.2 kcal/100 g and 70.32 % respectively. Optimized instant corn based dessert mix powder consisted of 29.75 % PCF, 50.99 % WMP, 4.25 % rice powder and 15 % sugar.

Raw bovine milk improves gut responses to feeding relative to infant formula in preterm piglets

For preterm neonates, the quality of the first milk is crucial for intestinal maturation and resistance to necrotizing enterocolitis (NEC). Among other factors, milk quality is determined by the stage of lactation and processing. We hypothesized that unprocessed mature bovine milk (BM; raw bovine milk) would have less bioactivity than corresponding bovine colostrum (BC) in a preterm pig model, but have improved bioactivity relative to its homogenized, pasteurized, spray-dried equivalent, whole milk powder (WMP), or a bovine milk protein-based infant formula (IF). For 5 days, newborn preterm pigs received parenteral and enteral nutrition consisting of IF (n = 13), BM (n = 13), or BC (n = 14). In a second study, WMP (n = 15) was compared with IF (n = 10) and BM (n = 9). Compared with pigs fed IF, pigs that were fed BM had significantly improved intestinal structure (mucosal weight, villus height) and function (increased nutrient absorption and enzyme activities, decreased gut permeability, nutrient fermentation, and NEC severity). BC further improved these effects relative to BM (lactase activity, lactose absorption, plasma citrulline, and tissue interleukin-8). WMP induced similar effects as BM, except for lactase activity and lactose absorption. In conclusion, the maturational and protective effects on the immature intestine decreased in the order BC>BM>WMP, but all three intact bovine milk diets were markedly better than IF. The stage of lactation (colostrum vs. mature milk) and milk processing (e.g., homogenization, fractionation, pasteurization, spray-drying) are important factors in determining milk quality during the early postnatal period of preterm neonates.

Inactivation of Cronobacter by gaseous ozone in milk powders with different fat contents

The inactivation of Cronobacter by gaseous ozone treatments was studied in whole milk powder (WMP) and skimmed-milk powder (SMP). Samples inoculated at 5.92 log cfu g−1 were exposed to a continuous stream of constant ozone concentrations of 2.8 and 5.3 mg L−1 for up to 120 min. Initial levels of Cronobacter in SMP were reduced by 2.71 and 3.28 log after 120 min of ozonation at 2.8 and 5.3 mg L−1, respectively. Counts were reduced by 1 log less in WMP after the same exposure period. The thiobarbituric acid reactive substances (TBARS) assay was used to monitor oxidation in milk powder samples and indicated that no significant (P > 0.05) changes occurred in the level of oxidation of WMP and SMP during ozonation at both ozone concentrations. Gaseous ozone treatment was found to be a promising method for the reduction of Cronobacter especially in SMP.

Evaluation of milk powder quality by protein oxidative modifications

The objective of the present research was to evaluate commercially available milk powders according to their protein oxidative modifications and antioxidant capacity, and to evaluate if these characteristics are related to physical quality parameters such as dispersibility or stability during storage. Fifteen commercially processed spray-dried milk powders were evaluated: 6 whole milk powders (WMP), 4 skim milk powders (SMP), and 5 infant formula powders (IFP). Protein oxidative status was measured as protein carbonyl (PC) content, dityrosine content, and extent of protein polymerization. The level of PC was slightly lower in SMP than in WMP, whereas IFP had more than twice as much PC as WMP (2.8±0.4, 2.1±0.2, and 6.5±1.3nmol/mg of protein for WMP, SMP, and IFP, respectively). No differences were detected in dityrosine accumulation. Although all the possible pairs of parameters were tested for correlations, we found that 4 parameters were linked: PC, whey content, protein aggregate level, and dispersibility. After 9 mo of storage at −20°C or room temperature, all milk samples were analyzed to evaluate changes in protein oxidative status (PC, dityrosine, and protein integrity) and related parameters. Compared with the initial condition, PC increased in all tested samples after 9 mo of storage at −20°C or at room temperature. Stored milk powders had increased PC and decreased dispersibility compared with prestorage levels. Our results highlight the importance of protein oxidative status in milk powder and its relationship to other related quality parameters, such as protein integrity and dispersibility. Our findings suggest that the understanding of such relationships could help in developing quality differentiation for different types of milk powders in the product market.