Whey protein concentrate and skimmed milk powder as encapsulation agents for coffee silverskin extracts processed by spray drying.

We tested the hypothesis that milk proteins, through microencapsulation, guarantee protection against bioactive substances in coffee silverskin extracts. Therefore, the aim of this study was to carry out technological, nutritional and physicochemical characterisation of a coffee silverskin extract microencapsulated using instant skim milk powder and whey protein concentrate as wall materials. The aqueous extract of coffee silverskin was spray-dried using 10% (w/v) skim milk powder and whey protein concentrate. The samples were characterised by determining the water content, water activity, particle size distribution, colour analysis and total phenolic compound content as well as antioxidant activity using 2,2-diphenyl-radical 1-picrylhydrazyl scavenging methods, nitric oxide radical inhibition and morphological analysis. The product showed water activity within a range that ensured greater stability, and the reduced degradation of the dried coffee silverskin extract with whey protein concentrate resulted in better rehydration ability. The luminosity parameter was higher and the browning index was lower for the encapsulated samples than for the pure coffee silverskin extract. The phenolic compound content (29.23 ± 8.39 and 34.00 ± 8.38 mg gallic acid equivalents/g for the coffee silverskin extract using skimmed milk powder and whey protein concentrate, respectively) and the antioxidant activity of the new product confirmed its potential as a natural source of antioxidant phenolic compounds. We conclude that the dairy matrices associated with spray drying preserved the bioactive and antioxidant activities of coffee silverskin extracts.

Proteoforms of ß-Casein, α-s1-Casein, α-Lactalbumin, Serum Albumin, and Lactotransferrin Identified in Different Lactation Phases of Human Milk by Proteomics Approach.

SCOPE: Human milk (HM) has a wide range of proteins with biological and nutritional functions, essential for newborns. The roles of proteins and their proteoforms in HM are not fully understood. This study aims to assess, by 2-DE proteomics, the differential proteoforms in HM, present in colostrum (COL), transition (TRA), and mature milk (MAT), aiming to contribute to understanding neonates' protein needs. METHODS AND RESULTS: HM samples are collected from 39 healthy lactating women. COL presents the higher concentration of essential amino acids. After MALDI-MS/MS and bioinformatics analysis, proteoforms are differentially detected. Abundances of ß-casein (CSN2), α-s1 casein, and α-lactalbumin (LALBA) are higher in MAT; CSN2s are found in 11 spots and the isoforms increase in size as the pI becomes more acidic; regarding LALBA, two variant forms are found with different abundances in TRA and MAT; CSN2, LALBA, lactotransferrin (LTF), and serum albumin forms are present in all lactation phases. CONCLUSION: This study reveals differential proteoforms in COL involved in tissue growth and body development, besides essential amino acids, and, in MAT, involved in muscle mass gain, strengthening of the immune system, and energy production. The results provide new insight about proteoforms involved in maturation of the newborn's organs and systems.

Microscopical Evaluation of the Effects of High-Pressure Processing on Milk Casein Micelles.

The effect of different high-pressure processing (HPP) treatments on casein micelles was analyzed through scanning electron microscopy (SEM) and a particle size distribution analysis. Raw whole and skim milk samples were subjected to HPP treatments at 400, 500 and 600 MPa for Come-Up Times (CUT) up to 15 min at ambient temperature. Three different phenomena were observed in the casein micelles: fragmentation, alterations to shape and agglomeration. The particle size distribution analysis determined that, as pressure and time treatment increased, the three phenomena intensified. First, the size of the casein micelles began to decrease as their fragmentation occurred. Subsequently, the casein micelles lost roundness, and their shape deformed. Finally, in the most intense treatments (higher pressures and/or longer times), the micelles fragments began to agglomerate, which resulted in an increase in their average diameter. Homogenization and defatting had no significant effect on the casein micelles; however, the presence of fat in whole milk samples was bioprotective, as the effects of the three phenomena appeared faster in treated skim milk samples. Through this study, it was concluded that the size and structure of casein micelles are greatly altered during high-pressure treatment. These results provide information that broadens the understanding of the changes induced on casein micelles by high-pressure treatments at room temperature.

Application of preliminary high-pressure processing for improving bioactive characteristics and reducing antigenicity of whey protein hydrolysates.

This study investigated the use of Novo Pro-D® (NPD) and Ficin (FC) as alternative proteases for the production of bioactive peptides with reduced allergenicity from whey protein concentrate (WPC). In addition, the use of high hydrostatic pressure processing as pre-treatment of WPC and its impact on the final characteristics of hydrolysates were also evaluated. NPD treatments generated hydrolysates with a 98% reduction of soluble proteins, greater in vitro antioxidant capacity, and less immunoreactivity when compared to FC ones. However, pre-treatment was an essential tool to improve WPC hydrolysis when FC was used, resulting in hydrolysates with less soluble proteins, enhanced antioxidant capacity, and less allergenicity compared with conventional hydrolysis. As for NPD, the pre-treatment of WPC improved the in vitro antioxidant capacity and resulted in a 100% reduction in immunoreactivity to ß-lactoglobulin in a shorter processing time. Importantly, bioactive peptides generated by FC displayed an improved ability to induce in vitro arterial relaxation, compared with those obtained from NPD process. Therefore, this study provides innovative evidence regarding how the proteases used for production of whey hydrolysates can improve its biological effects, and discloses the use of high hydrostatic pressure combined with enzymatic hydrolysis as a promising alternative to produce hydrolysates with improved properties.

Fructans with different degrees of polymerization and their performance as carrier matrices of spray dried blue colorant.

Inulin-type fructans with different degrees of polymerization (DPs) were used as wall materials for the blue colorant produced from the crosslinking between genipin and milk proteins. The impact of using fructooligosaccharides (FOS) with DP = 5 and inulins with DP ≥ 10 (GR-In) and DP ≥ 23 (HP-In) on the physical (microstructure, size, water activity, wettability, solubility, water adsorption, glass transition temperature, and color), chemical (free genipin retention and moisture), and technological (colorant power, pH stability, and thermal stability) properties of the powdered blue colorant was examined. Inulins were more efficient carriers as seen from the physical characteristics of the microparticles. FOS and GR-In promoted higher retention of free genipin than HP-In. Additionally, their lower DP influenced the rehydration proprieties as well as the color intensity and colorant power. The DP did not affect the physical stability of the colorant at different pH conditions or at high temperature. Our findings demonstrated that the DP of the fructan exhibited a strong impact on the blue intensity of the samples and also their rehydration capacity.

Orange juice industry by-product silage can increase fat and protein in Holstein cow's milk.

We aimed to evaluate the effect of replacing corn silage by orange peel silage on nutrient intake, ruminal parameters and milk production of multiparous lactating Holstein cows. Eight fistulated Holstein cows averaging 587.5 ± 39.6 kg and 111 ± 22 d in milking were randomly assigned to a double 4 × 4 Latin square design carried out two times to determine the effects of feeding with orange peel silage (OPS) in substitution of whole plant corn silage (WPCS). The treatments were a control diet with WPCS only or diets with OPS replacing WPCS in the total mixed diet (250, 500, or 750 g/kg DM). All cows were fed the same 750 : 250 g/kg roughage : concentrate ratio. The DM intake and milk production were reduced with the OPS inclusion, with decreases in consumption of neutral detergent fibre and increased consumption of non-fibrous carbohydrates. Diets with 250 and 500 g/kg OPS showed similar milk production and protein content in milk to the standard WCPS diet, whilst 750 g/kg orange peel silage as roughage increased fat and protein contents significantly. The orange peel silage as a substitute for corn silage for feeding dairy cows did not show adverse changes in the rumen environment and showed promising results in the increase of fat in milk of Holstein cows.

Glycomacropeptide Ameliorates Indomethacin-Induced Enteropathy in Rats by Modifying Intestinal Inflammation and Oxidative Stress.

Nonsteroidal anti-inflammatory drug (NSAID)-induced enteropathy is considered a serious and increasing clinical problem without available treatment. Glycomacropeptide (GMP) is a 64-amino acid peptide derived from milk κ-casein with numerous biological activities. The aim of this study was to investigate the protective effect of GMP on NSAID enteropathy in rats. Enteropathy was induced by seven days oral indomethacin administration. Rats were orally GMP treated from seven days previous and during the establishment of the enteropathy model. Changes in metabolism, hematological and biochemical blood alterations, intestinal inflammation and oxidative damage were analyzed. Integrity barrier markers, macroscopic intestinal damage and survival rate were also evaluated. GMP treatment prevented anorexia and weight loss in animals. Furthermore, prophylaxis with GMP ameliorated the decline in hemoglobin, hematocrit, albumin and total protein levels. The treatment had no therapeutic efficacy on the decrease of occludin and mucin (MUC)-2 expression in intestinal tissue. However, GMP markedly decreased neutrophil infiltration, and CXCL1, interleukin-1ß and inducible nitric oxide synthase expression. Nitric oxide production and lipid hydroperoxide level in the small intestine were also diminished. These beneficial effects were mirrored by preventing ulcer development and increasing animal survival. These results suggest that GMP may protect against NSAID enteropathy through anti-inflammatory and antioxidant properties.

Effect of dietary crude protein degradability and corn processing on lactation performance and milk protein composition and stability.

The present study aimed to evaluate the effect of crude protein degradability and corn processing on lactation performance, milk protein composition, milk ethanol stability (MES), heat coagulation time (HCT) at 140°C, and the efficiency of N utilization for dairy cows. Twenty Holstein cows with an average of 162 ± 70 d in milk, 666 ± 7 kg of body weight, and 36 ± 7.8 kg/d of milk yield (MY) were distributed in a Latin square design with 5 contemporaneous balanced squares, 4 periods of 21 d, and 4 treatments (factorial arrangement 2 × 2). Treatment factor 1 was corn processing [ground (GC) or steam-flaked corn (SFC)] and factor 2 was crude protein (CP) degradability (high = 10.7% rumen-degradable protein and 5.1% rumen-undegradable protein; low = 9.5% rumen-degradable protein and 6.3% rumen-undegradable protein; dry matter basis). A significant interaction was observed between CP degradability and corn processing on dry matter intake (DMI). When cows were fed GC with low CP degradability, DMI increased by 1.24 kg/d compared with cows fed GC with high CP degradability; however, CP degradability did not change DMI when cows were fed SFC. Similar interactions were observed for MY, HCT, and lactose content. When cows were fed GC diets, high CP degradability reduced MY by 2.3 kg/d, as well as HCT and lactose content, compared with low CP degradability. However, no effect of CP degradability was observed on those variables when cows were fed SFC diets. The SFC diets increased dry matter and starch total-tract digestibility and reduced ß-casein (CN) content (% total milk protein) compared with GC diets. Cows fed low-CP degradability diets had higher glycosylated κ-CN content (% total κ-CN) and MES, as well as milk protein content, 3.5% fat-corrected milk, and efficiency of N for milk production, than cows fed high-CP degradability diets. Therefore, GC and high-CP degradability diets reduced milk production and protein stability. Overall, low CP degradability increased the efficiency of dietary N utilization and MES, probably due to changes in casein micelle composition, as CP degradability or corn processing did not change the milk concentration of ionic calcium. The GC diets increased ß-CN content, which could contribute to reducing HTC when cows were fed GC and high-CP degradability diets.

Spray-dried novel structured lipids enriched with medium-and long-chain triacylglycerols encapsulated with different wall materials: Characterization and stability.

Novel structured lipids (SLs) enriched with medium-and long-chain triacylglycerols (MLCTs) were synthesized to combine the benefits of both arachidonic acid and medium-chain fatty acids; however, they are susceptible to oxidative degradation. In this work, the influences of the partial replacement of whey protein isolate (WPI) as the primary wall material by prebiotic carbohydrates, such as maltodextrin (MD) and inulin (IN) as the secondary wall materials on the physicochemical characteristics and oxidative stability of the spray-dried MLCTs-rich SLs microcapsules were investigated. The highest values of viscosity and zeta-potential were achieved by the WPI/IN (1:1) emulsions. Size distributions of all the emulsions were mono modal and became bimodal after microencapsulation process. The microcapsules prepared with WPI/IN (1:1) had the lowest lightness and the highest yellowness values. The partial replacement treatments increased the solubility and reduced the moisture content of the produced microcapsules. The partial replacement of WPI by IN significantly enhanced the encapsulation efficiency (89.10 ±â€¯1.03%), wettability properties (205 ±â€¯10.61 S), and decreased the incidence of surface oil on the microcapsules. The free oil content was noted as 5.73 ±â€¯0.05, 3.83 ±â€¯0.01, and 2.40 ±â€¯0.03% for the microcapsules produced using WPI, WPI/MD (1:1), and WPI/IN (1:1), respectively. Larger microcapsules and fairer flowing properties were achieved in the powders produced with only WPI. The partial replacement of WPI by IN provided the best oxidative stability of the microencapsulated MLCTs-rich SLs. The results revealed that MD and IN with WPI together, particularly IN proved to be a good substitute secondary wall material for spray-dried MLCTs-rich SLs, therefore suggesting its usefulness in functional food applications.

Brazilian artisanal ripened cheeses as sources of proteolytic lactic acid bacteria capable of reducing cow milk allergy.

AIM: The objective was to obtain lactic acid bacteria (LAB) capable of hydrolysing immunoreactive proteins in milk, to optimize the hydrolysis, to determine the proteolysis kinetics and to test the safety of the best hydrolytic strain. METHODS AND RESULTS: Brazilian cheese was used as source of LAB capable of hydrolysing main milk allergens. Proteolytic isolates were submitted to RAPD-PCR for the characterization of clonal diversity. Optimized hydrolysis was strain and protein fraction dependent. 16S rDNA sequencing identified three proteolytic strains: Enterococcus faecalis VB43, that hydrolysed αS1 -, αS2 - and ß-caseins, α-lactalbumin and ß-lactoglobulin (partial hydrolysis), and Pediococcus acidilactici VB90 and Weissella viridescens VB111, that caused partial hydrolysis of αS1 - and αS2 -caseins. Enterococcus faecalis VB43 tested negative for virulence genes asa1, agg, efaA, hyl, esp, cylLL and cylLS but positive for genes ace and gelE. Ethylenediamine tetra-acetic acid inhibited the proteolysis, indicating that the main proteases of E. faecalis VB43 are metalloproteases. CONCLUSION: Brazilian artisanal cheese is a good source of LAB capable of hydrolysing allergenic proteins in milk. One isolate (E. faecalis VB43) presented outstanding activity against these proteins and lacked most of the tested virulence genes. SIGNIFICANCE AND IMPACT OF THE STUDY: Enterococcus faecalis VB43 presents good potential for the manufacture of hypoallergenic dairy products.

Gut peptidases from a specialist herbivore of latex plants are capable of milk protein hydrolysis: Inputs for hypoallergenic milk formulas.

Transitory allergies to cow milk proteins in infants or adults have become a public health problem. Although extensively or partially hydrolyzed cow milk protein formulas are available, these products are costly. Therefore, studies into innovative enzymes to digest cow milk proteins are needed. Danaus plexippus gut peptidases were purified and examined with regard to cow milk protein hydrolysis. The peptidases hydrolyzed caseins and whey proteins. However, after heat treatment, there was a significant improvement in ß-lactoglobulin hydrolysis. The hydrolyzed cow milk proteins were not recognized by anti-casein antibodies and only reacted slightly with antibodies against whey proteins. This performance was better than that of partially hydrolyzed formulas and similar to that of an extensively hydrolyzed formula. These results suggest that D. plexippus gut peptidases are suitable and innovative enzymes to produce hypoallergenic cow milk protein formulas.

Proteomic and peptidomic profiling of Brazilian artisanal 'Coalho' cheese.

BACKGROUND: Artisanal 'Coalho' cheese is a product typically popular in the Brazilian north-eastern region. Production of this cheese represents about 9.2% of the internal crude product of Pernambuco State. Several peptides are generated from hydrolysis of αS1 -, αS2 -, ß-, and κ-caseins during manufacture of this cheese. The commercial importance of Brazilian artisanal 'Coalho' cheese justifies the examination of both the protein and peptide profiles of cheeses from six cities of the semi-arid region of Pernambuco State, Brazil. RESULTS: SDS-PAGE of the aqueous extracts of 'Coalho' cheeses (WSP) showed bands of lactoferrin, ß-lactoglobulin, ß-lactoglobulin (dimer), α-lactoalbumin, bovine serum albumin, α-casein, ß-casein, κ-casein and para-κ-casein. A total of 57 to 72 peptides were confirmed by mass spectra in the different samples of 'Coalho' cheese which 32 known peptides (11 from αS1 -casein, three from αS2 -casein, 15 from ß-casein and three from κ-casein), comprising seven caseinphosphopeptides. Among the unidentified peptides, three showed high intensity peaks in all 'Coalho' cheeses studied (with molecular weights of 1597, 1725/1726, 2778/2779 Da). CONCLUSION: The proteomic studies revealed peptides that may represent molecular markers or fingerprints for investigating the quality control and regional characterisation of these 'Coalho' cheeses. © 2016 Society of Chemical Industry.

Evaluation of the synergistic effects of milk proteins in a rapid viscosity analyzer.

Protein systems (PS) are routinely used by companies from Brazil and around the globe to improve the texture, yield, and palatability of processed foods. Understanding the synergistic behavior among the different protein structures of these systems during thermal treatment under the influence of pH can help to better define optimum conditions for products and processes. The interpretation of the reactions and interactions that occur simultaneously among the protein constituents of these systems as dispersions during thermal processing is still a major challenge. Here, using a rapid viscosity analyzer, we observed the rheological changes in the startup viscosities of 5 PS obtained by combining varying proportions of milk protein concentrate and whey protein concentrate under different conditions of pH (5.0, 6.5, and 7.0) and heat processing (85°C/15min and 95°C/5min). The solutions were standardized to 25% of total solids and 17% of protein. Ten analytical parameters were used to characterize each of the startup-viscosity ramps for 35 experiments conducted in a 2×3 × 5 mixed planning matrix, using principal component analysis to interpret behavioral similarities. The study showed the clear influence of pH 5.5 in the elevation of the initial temperature of the PS startup viscosity by at least 5°C, as well as the effect of different milk protein concentrate:whey protein concentrate ratios above 15:85 at pH 7.0 on the viscographic profile curves. These results suggested that the primary agent driving the changes was the synergism among the reactions and interactions of casein with whey proteins during processing. This study reinforces the importance of the rapid viscosity analyzer as an analytical tool for the simulation of industrial processes involving PS, and the use of the startup viscosity ramp as a means of interpreting the interactions of system components with respect to changes related to the treatment temperature.

Economic Burden of Atopic Dermatitis in High-Risk Infants Receiving Cow's Milk or Partially Hydrolyzed 100% Whey-Based Formula.

OBJECTIVE: To estimate the health and economic impact of feeding partially hydrolyzed formula-whey (PHF-W) instead of standard cow's milk formula (CMF) for the first 4 months of life among US infants at high risk for developing atopic dermatitis (AD). STUDY DESIGN: A Markov model was developed integrating published data, a survey of US pediatricians, costing sources and market data, and expert opinion. Key modeled outcomes included reduction in AD risk, time spent post AD diagnosis, days without AD flare, and AD-related costs. Costs and clinical consequences were discounted at 3% annually. RESULTS: An estimated absolute 14-percentage point reduction in AD risk was calculated with the use of PHF-W compared with CMF (95% CI for difference, 3%-22%). Relative to CMF, PHF-W decreased the time spent post-AD diagnosis by 8.3 months (95% CI, 2.78-13.31) per child and increased days without AD flare by 39 days (95% CI, 13-63) per child. The AD-related, 6-year total cost estimate was $495 less (95% CI, -$813 to -$157) per child with PHF-W ($724 per child; 95% CI, $385-$1269) compared with CMF ($1219 per child; 95% CI, $741-$1824). CONCLUSION: Utilization of PHF-W in place of CMF as the initial infant formula administered to high-risk US infants not exclusively breastfed during the first 4 months of life may reduce the incidence and economic burden of AD. Broad implementation of this strategy could result in a minimum savings of $355 million per year to society.

Effect of commercial grape extracts on the cheese-making properties of milk.

Grape extracts can be added to milk to produce cheese with a high concentration of polyphenols. Four commercial extracts from whole grape, grape seed, and grape skin (2 extracts) were characterized and added to milk at concentrations of 0, 0.1, 0.2, and 0.3% (wt/vol). The effect of grape extracts on the kinetics of milk clotting, milk gel texture, and syneresis were determined, and model cheeses were produced. Whole grape and grape seed extracts contained a similar concentration of polyphenolic compounds and about twice the amount found in grape skin extracts. Radical scavenging activity was directly proportional to the phenolic compounds content. When added to milk, grape extracts increased rennet-induced clotting time and decreased the clotting rate. Although differences were observed between the extracts, the concentration added to milk was the main factor influencing clotting properties. With increasing concentrations of grape extracts, milk gels showed increased brittleness and reduced firmness. In addition, syneresis of milk gels decreased with increasing concentrations of grape extracts, which resulted in cheeses with a higher moisture content. The presence of grape extracts in milk slightly increased protein recovery in cheese but had no effect on fat recovery. With whole grape or grape seed extracts added to milk at 0.1% (wt/vol), the recovery coefficient for polyphenols was about 0.63, and decreased with increasing extract concentration in milk. Better polyphenol recovery was observed for grape seed extracts (0.87), with no concentration effect. Commercial extracts from whole grape, grape seed, or grape skin can be added to milk in the 0.1 to 0.3% (wt/vol) concentration range to produce cheese with potential health benefits, without a negative effect on cheese yield.

Starch levels on performance, milk composition and energy balance of lactating dairy cows.

The objective of this experiment was to evaluate the effects of starch levels in diets with the replacement of citrus pulp for corn on milk yield, milk composition, and energy balance of lactating dairy cows. Twenty-eight multiparous Holstein cows were used in seven 4 × 4 Latin squares conducted concurrently, and each experimental period consisted of 20 days (16 days for adaptation and 4 days for sampling). The experimental treatments comprised four starch levels: 15, 20, 25, and 30% in the diet. The dry matter intake increased linearly with increasing starch levels. The milk yield and 3.5% fat-corrected milk yield showed quadratic response to increasing starch levels. The milk protein content and milk total solids content responded linearly to increasing starch levels. The feed efficiency, milk lactose content, milk urea nitrogen, plasma urea nitrogen, and plasma glucose concentration were not affected by starch levels. The estimated net energy for lactation (NEL) intake increased linearly as the starch level was raised. Although the milk NEL output per kilogram of milk was not affected by starch, the milk NEL output daily responded quadratically to starch levels. In addition, the NEL in body weight gain also responded quadratically to increasing starch levels. The efficiency of energy use for milk yield and the NEL efficiency for production also responded quadratically to increasing starch levels. Diets for mid-lactating dairy cows producing around 30 kg/day of milk should be formulated to provide around 25% starch to optimize performance.

Hydrolysates of sheep cheese whey as a source of bioactive peptides with antioxidant and angiotensin-converting enzyme inhibitory activities.

Enzymatic proteolysis may be employed to release bioactive peptides, which have been investigated for potential benefits from both technological and human health perspectives. In this study, sheep cheese whey (SCW) was hydrolyzed with a protease preparation from Bacillus sp. P7, and the hydrolysates were evaluated for antioxidant and angiotensin I-converting enzyme (ACE)-inhibitory activities. Soluble protein and free amino acids increased during hydrolysis of SCW for up to 4h. Antioxidant activity of hydrolysates, evaluated by the 2,2'azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid radical scavenging method, increased 3.2-fold from 0 h (15.9%) to 6h of hydrolysis (51.3%). Maximum Fe(2+) chelation was reached in 3h hydrolysates, and the reducing power peaked at 1h of hydrolysis, representing 6.2 and 2.1-fold increase, respectively, when compared to that of non-hydrolyzed SCW. ACE inhibition by SCW (12%) was improved through hydrolysis, reaching maximal values (55% inhibition) in 4h, although 42% inhibition was already observed after 1h hydrolysis. The peptide LAFNPTQLEGQCHV, derived from ß-lactoglobulin, was identified from 4-h hydrolysates. Such a biotechnological approach might be an interesting strategy for SCW processing, potentially contributing to the management and valorization of this abundant dairy byproduct.

A control method to inspect the compositional authenticity of Minas Frescal cheese by gel electrophoresis.

This study introduces a qualitative method to inspect the compositional authenticity of white nonripened cheeses like Minas Frescal, a typical Brazilian cheese, especially when irregular replacement of milk by whey is suspected. A sodium dodecyl sulfate gel electrophoresis (SDS-PAGE) method, followed by image densitometry, was validated. Cheeses were freeze-dried to electrophoresis, and ß-lactoglobulin (ß-LG) was chosen as the adulteration marker. In gel trypsin digestion followed by matrix assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry provided its identification. Cheeses with a minimum of 14 mg·g(-1) of ß-LG are considered to be adulterated. The method shows satisfactory precision with a detection limit of 7 mg·g(-1). Forty-two commercial samples from inspected establishments were then assessed and subjected to cluster analysis. Compliant and noncompliant groups were set with 24 (57%) authentic samples and 18 (43%) adulterated samples, respectively, showing that proper analytical monitoring is required to inhibit this practice.

Freezing and thawing effects on fat, protein, and lactose levels of human natural milk administered by gavage and continuous infusion / Efeito do congelamento e descongelamento nos níveis de gordura, proteína e lactose do leite humano natural administrados por gavagem e infusão contínua

OBJECTIVES: to analyze the changes in human milk macronutrients: fat, protein, and lactose in natural human milk (raw), frozen and thawed, after administration simulation by gavage and continuous infusion. METHOD: an experimental study was performed with 34 human milk samples. The infrared spectrophotometry using the infrared analysis equipment MilkoScan Minor(r) (Foss, Denmark) equipment was used to analyze the macronutrients in human milk during the study phases. The analyses were performed in natural (raw) samples and after freezing and fast thawing following two steps: gavage and continuous infusion. The non-parametric Wilcoxon test for paired samples was used for the statistical analysis. RESULTS: the fat content was significantly reduced after administration by continuous infusion (p < 0.001) during administration of both raw and thawed samples. No changes in protein and lactose content were observed between the two forms of infusion. However, the thawing process significantly increased the levels of lactose and milk protein. CONCLUSION: the route of administration by continuous infusion showed the greatest influence on fat loss among all the processes required for human milk administration. .

OBJETIVO: analisar as alterações dos macronutrientes gordura, proteína e lactose no leite humano natural, congelado e descongelado, após a simulação da administração da dieta por gavagem e infusão contínua. MÉTODO: foi conduzido um estudo experimental com 34 amostras de leite humano. Foi utilizada a técnica da espectofotometria infravermelha (Milko Scan Minor(r)) para analisar os macronutrientes do leite humano nas etapas do estudo. As amostras foram analisadas na forma natural (crua) e após congelamento e descongelamento rápido nas duas formas de infusão: gavagem e infusão contínua. Foi usado o teste não paramétrico de Wilcoxon para amostras pareadas na análise estatística. RESULTADO: a gordura apresentou redução significativa após administração por infusão contínua (p < 0,001), tanto durante administração na forma natural quanto na forma descongelada. Não houve alteração da proteína e lactose segundo forma de infusão no leite descongelado e no leite in natura. O processo de descongelamento aumentou significativamente os níveis de lactose e de proteína do leite. CONCLUSÃO: a via de administração por infusão contínua foi o procedimento que mais influenciou na perda de gordura, dentre todos os processos necessários para administração do leite humano. .

Freezing and thawing effects on fat, protein, and lactose levels of human natural milk administered by gavage and continuous infusion.

OBJECTIVES: to analyze the changes in human milk macronutrients: fat, protein, and lactose in natural human milk (raw), frozen and thawed, after administration simulation by gavage and continuous infusion. METHOD: an experimental study was performed with 34 human milk samples. The infrared spectrophotometry using the infrared analysis equipment MilkoScan Minor® (Foss, Denmark) equipment was used to analyze the macronutrients in human milk during the study phases. The analyses were performed in natural (raw) samples and after freezing and fast thawing following two steps: gavage and continuous infusion. The non-parametric Wilcoxon test for paired samples was used for the statistical analysis. RESULTS: the fat content was significantly reduced after administration by continuous infusion (p<0.001) during administration of both raw and thawed samples. No changes in protein and lactose content were observed between the two forms of infusion. However, the thawing process significantly increased the levels of lactose and milk protein. CONCLUSION: the route of administration by continuous infusion showed the greatest influence on fat loss among all the processes required for human milk administration.