Lactose Levels Research Articles

Conversion of milk lactose to galacto-oligosaccharides by enzymes to produce prebiotic enriched cheese

In this study, lactose in milk is converted to galacto-oligosaccharides (GOS) using β-gal from Kluveromyces lactis. Trans-galactosylation was done by adding 1 mL of β-gal in 1L milk at 42°C for 2 hours with continuous agitation. Subsequently, the cheese prepared from the GOS enriched milk and control milk were compared for the physico-chemical and organoleptic properties. The chemical composition of prebiotic cheese exhibited non-significant differences for the fat, protein, moisture and ash, whereas a significantly lower level of lactose (56.25%) was observed as compared to control cheese. Organoleptic evaluation showed that the prebiotic cheese has a similar appearance and overall acceptability as does the control cheese except for taste and texture which were improved by trans-glycosylation.

Daytime Grazing in Mountainous Areas Increases Unsaturated Fatty Acids and Decreases Cortisol in the Milk of Holstein Dairy Cows.

Simple SummaryThe effects of grazing dairy cows in mountainous areas for 12 and 24 h compared with keeping the cows under confined settings were evaluated by examining the overall levels of fatty acids and cortisol in milk as an indicator of stress. Our findings revealed favorable changes in cows grazing for 12 h, with significantly improved milk fatty acid profile and decreased milk cortisol content. Additionally, we found no significant changes in the milk yield of 12 h grazed cows compared to the control group of confined cows, while milk fat and protein showed higher values in 12 h grazed cows. Grazing for 24 h caused a significant decrease in the milk yield compared to the two other groups. Overall, grazing for 12 h in a mountainous area is suggested to be beneficial for animal welfare, with positive improvements in milk fatty acids and lessening of stress levels without adverse effects on milk yield.The effects of grazing lactating cows in mountainous areas for 12 and 24 h compared with the confined indoor system were evaluated by examining the overall milk fatty acid and cortisol. Twenty-one dairy cows were allocated to three treatment groups: (1) control (confined management system in a free-stall barn; TMR based), (2) grazing for 12 h (12 hG; TMR plus grazing pasture), and (3) grazing for 24 h (24 hG; pasture-based feeding system). Dry matter intake was higher in the control and 12 hG groups than in the 24 hG group. The yields of total milk and the 3.5% fat-corrected milk were the lowest in the 24 hG group. Milk fat was the highest in the 24 hG group and higher in 12 hG compared with the control group. Milk protein and lactose levels were the highest in the 12 hG group. The highest somatic cell count was observed in the 24 hG group. The saturated fatty acid levels were higher in the control group compared with the 12 hG and 24 hG groups. There was no difference in overall mono-unsaturated fatty acids between 12 hG and 24 hG groups. Poly-unsaturated fatty acids were higher in the 12 hG group compared with the control and 24 hG groups. There was no difference in omega-6 (ω-6) fatty acids among the groups, and omega-3 fatty acids were higher in the 12 hG group than in the control group. Milk cortisol was the highest in the 24 hG group and higher in the control group compared with the 12 hG group. Taken together, grazing for 12 h is advisable for farms that have access to mountainous areas to improve the milk fatty acid profile and decrease the stress levels in high-yielding Holstein lactating cows.

Nuclear magnetic resonance spectroscopy to investigate the association between milk metabolites and udder quarter health status in dairy cows

Nuclear magnetic resonance spectroscopy was applied to investigate the association between milk metabolome and udder quarter health status in dairy cows. Mammary gland health status was defined by combining information provided by traditional somatic cell count (SCC) and differential SCC (DSCC), which expresses the percentage of neutrophils and lymphocytes over total SCC. Quarter milk samples were collected in triplicate (d 1 to 3) from 10 Simmental cows, 5 defined as cases and 5 defined as controls according to SCC levels at d 0. A total of 120 samples were collected and analyzed for bacteriology, milk composition, SCC, DSCC, and milk metabolome. Bacteriological analysis revealed the presence of mostly coagulase-negative staphylococci in quarter milk samples of cows defined as cases. Nuclear magnetic resonance spectra of all quarter samples were first analyzed using the unsupervised multivariate approach principal component analysis, which revealed a specific metabolomic fingerprint of each cow. Then, the supervised cross-validated orthogonal projections to latent structures discriminant analysis unquestionably showed that each cow could be very well identified according to its milk metabolomic fingerprint (accuracy = 95.8%). The comparison of 12 different models, built on bucketed 1-dimensional NOESY spectra (noesygppr1d, Bruker BioSpin) using different SCC and DSCC thresholds, corroborated the assumption of improved udder health status classification ability by joining information provided by both SCC and DSCC. Univariate analysis performed on the 34 quantitated metabolites revealed lower levels of riboflavin, galactose, galactose-1-phosphate, dimethylsulfone, carnitine, hippurate, orotate, lecithin, succinate, glucose, and lactose, and greater levels of lactate, phenylalanine, choline, acetate, O-acetylcarnitine, 2-oxoglutarate, and valine, in milk samples with high somatic cells. In the 5 cases, results of the udder quarter with the highest SCC compared with its symmetrical relative were in line with quarter-level findings. Our study suggests that increased SCC is associated with changes in milk metabolite fingerprint and highlights the potential use of different metabolites as novel indicators of udder health status and milk quality.

Improving LC-MS analysis of human milk B-vitamins by lactose removal

Our previously reported, first validated, UPLC-MS/MS-based simultaneous analysis of five human milk B-vitamins revealed severe matrix effects. High levels of endogenous lactose fouled the electrospray ionization source affecting the analysis. We evaluated solid-phase extraction (SPE), liquid–solid extraction (LSE), protein precipitation (PPT), and liquid chromatography effluent diversion for lactose-removal. SPE failed to separate lactose from vitamins; LSE using 2-propanol reduced lactose and vitamin recoveries. PPT-solvent, milk volume, and reconstitution solvent influenced flavin adenine dinucleotide, pyridoxal and nicotinamide recoveries. Using an optimized LC-gradient enabled chromatographic separation of lactose from vitamins and its removal using a post-column switch-valve. Only 40 µL milk was subjected to methanol-PPT and non-polar matrix removal by methyl tert-butyl ether. B-vitamin recoveries were established (81.9–118.6%; CV ≤ 11.9%; precision: 4.9–13.7%) with greatly reduced matrix effects, and improved process efficiency, and recovery.

Composition and Therapeutic Applications of Goat Milk and Colostrum

Goats are categorized under the small ruminants which required less fodder and a small area for shelter. Both goat milk (GM) and colostrum (GC) are secreted from the mammary glands of goats. The level of nutritional and bioactive components found to be at an elevated level in colostrum within 72 hours, which reach a normal level as the time increases from parturition. Recently an increased interest in goat milk and colostrum has been seen throughout the world due to the natural exitance of vital components including immunoglobins, growth factors, hormones, lactoferrin, and lysozyme. The compositional parameter of both GM and GC is significantly altered by genetic and environmental factors. The sialic acid is a prime component of goat colostrum which assists in brain development. The small size fat globules of goat milk make it more tolerable and digestible as compared to other milk sources. GM is composed of low level of lactose which can be consumed easily by lactose-intolerant individuals. Different GM and GC-based products viz yogurt, ice cream, infants’ formulas are prepared and commercialized globally. The nutritional components of GM and GC improve overall body growth and development. Where the bioactive components are clinically proven in the prevention and pre-treatment of numerous chronic diseases.

Composition and microbiological quality of raw milk refrigerated in community tanks

Milk is rich in nutrients, but several factors in the production system interfere with its quality. The objective of this study was to analyze the composition and microbiological quality of raw milk stored in community tanks from the municipality of Aricanduva – Minas Gerais. Samples were collected from eight community tanks at different properties. The milk composition and temperature were analyzed using the digital milk analyzer. The total count of aerobic mesophilic microorganisms was performed at the Laboratory of Science and Technology of Products of Animal Origin, Department of Animal Science, Federal University of Vales do Jequitinhonha and Mucuri, Diamantina – Minas Gerais. The data obtained were compared to the values established by Normative Instruction (IN) n° 76, by means of Student's t-test and Wilcoxon's non-parametric test at the level of 5% of significance. The average levels of fat (3.55 g/100g), protein (3.00 g/100g), lactose (4.45 g/100g) and total solids (11.76 g/100g) were within the standards minimum required. The content of defatted solids (8.21 g/100g) was the limiting factor to the compliance with IN76, with an average value lower than that established (8.40 g/100g). The temperature of the milk was higher than the standard required by the legislation and the count of mesophilic microorganisms did not differ from the legislation. It is concluded that the composition of raw milk stored in community tanks in the municipality of Aricanduva – Minas Gerais, compared to IN 76, did not fully met the legislation in all evaluated parameters.

Anti-Inflammatory and Antibacterial Potential of Qicao Rukang Powder in Bovine Subclinical Mastitis.

Background Subclinical mastitis is one of the most common reproductive diseases in dairy cows. Qicao Rukang powder is a Chinese herbal compound mixture developed to treat subclinical mastitis in dairy cows by clearing heat, tonifying qi, and improving blood and milk circulation. The study aimed to determine the anti-inflammatory and antimicrobial efficacy of Qicao Rukang powder in treating subclinical mastitis in dairy cows at the manufacturer's recommended dose. Methods Forty (40) Holstein dairy cows with milk somatic cell count (SCC) ≥ 500,000 cellml−1 were randomly assigned to treatment (n = 20) and control (n = 20) groups. Cows in the treatment group were administered with 150 grams of Qicao Rukang powder orally for five days, while the control group received no treatment. The authors analyzed the milk SCC, milk composition, bacteriological cure rate of the drug, blood serum levels of interleukins (IL-6, IL-1β, and IL-8), tumor necrosis factor (TNF-α), and interferon gamma (INF-γ) quantified by using ELISA kits on day 0 and day 6. Results SCC of the treated group reduced very significantly (P < 0.001) compared with the control group. Milk fat, protein, and total solids increased significantly (P < 0.05) after treatment, whereas lactose and milk urea nitrogen levels showed a nonsubstantial rise. The bacteriological cure percentage of Qicao Rukang powder therapy was 77.8% for Aeromonas spp. (14 of 18), 75% for Pseudomonas spp. (6 of 8), and 100% for Acinetobacter spp. and Enterococcus spp. giving 81.8% cured for all isolates (27 of 33). Only 26.7% (8 of 30) of untreated cows recovered spontaneously. Analysis of IL-1β, IL-6, and INF-γ in the blood serum of the treated group revealed a significant decrease (P < 0.01) with nonsignificant rises in TNF-α and IL-8 levels. Conclusions This research demonstrates that Qicao Rukang powder has potent antibacterial and anti-inflammatory actions, supporting its use as an alternative to conventional treatment for subclinical dairy cow mastitis. However, further investigations will be required to explain the role of the active ingredients and the mechanisms involved in the pharmacological activities of the Qicao Rukang powder.

Shotgun proteomics of homogenate milk reveals dynamic changes in protein abundances between colostrum, transitional, and mature milk of swine

Milk is an easily digestible source of nutrients and bioactive factors, its composition reflects the neonate’s needs, and changes from colostrum to transitional and mature milk. Our objective was to measure milk fat, lactose, total carbohydrate, and protein content in parallel with global proteome of homogenate milk samples to characterize changes across the three phases of swine lactation. Milk samples were collected from multiparous sows (n = 9) on postnatal day 0 (D0; colostrum), 3 (D3; early transitional), 7 (D7; late transitional), and 14 (D14; mature). On D3, percent fat (16 ± 2.1) and lactose (3.8 ± 0.3) were higher (P < 0.05) than on D0 (10 ± 3.9 and 1.5 ± 0.3, respectively). Levels of fat and lactose were not different between D3 and D14. Percent total protein decreased (P < 0.05) between D0 (11 ± 2.1) and D3 (5 ± 0.7), but there was no significant change in percent protein between D3 and D14. Total carbohydrates increased (P < 0.05) between D3 (944 ± 353 µg/mL) and D14 (1,150 ± 462 µg/mL). Quantitative proteomic analysis using liquid chromatography tandem mass spectrometry (LC-MS/MS) of homogenate D0, D3, and D14 milk samples (n = 6) identified 772 protein groups which corresponded to 501 individual protein-coding genes. A total of 207 high confidence proteins were detected in n = 3 sows/day. Of the high confidence proteins, 81 proteins were common among all 3 days of lactation. Among the proteins that decreased between the days (false discovery rate; FDR < 0.05) were multiple apolipoproteins and XDH which decreased between D0 to D3. Proteins that increased across the days (FDR < 0.05) were complement factors and 14-3-3 proteins (YWHAQ, YWHAE). Our data provide a good characterization of milk proteome changes that likely reflect mammary function as well as the neonate’s phase-specific developmental needs. This data may be useful in developing approaches to enhance the health and welfare of swine.

CHARACTERISTICS OF THE YOGURT BEING INCUBATED IN GREEN COCONUT SHELL (Cocos nucifera L. var. viridis Hassk)

&#x0D; &#x0D; &#x0D; The study aims to identify characteristics of the yogurt being incubated in green coconut shell (Cocos nucifera L. var. viridis Hassk). It was conducted in March 2020 at the Laboratory of Animal Product Technology and Mic- robiology Faculty of Animal Science, Udayana University. This studies used a Complete Random Design (CDR) with three treatments and five replications. The three treatments were incubated in a jar container (control) (P0), incubated in green coconut shell nonflesh (P1) and incubated in green coconut shell with flesh (P2). The variables observed were lactoce level, fat level, protein level and pH value. The results of this study have shown that yogurt’s characteristic indicated lactose and protein levels was not significantly different (P&gt;0,05) in all treatments, but P2 fat levels was higher significantly (P&lt;0,05) different than P1 and P0. pH values was not significantly different (P&gt;0,05) with P1 and significantly different (P&lt;0,05) with P0. Conclusing in this study that the characteristics of yogurt incubated in green coconut shell getting good results at lactose level 2,32,42%; fat level 10,60-12,50%; pro- tein level 4,80-4,90%; and value pH 4,14-4,24%.&#x0D; &#x0D; &#x0D;

Energized calf milk: is it worth investing in early life nutrition?

Research has indicated that daily liveweight gain (DLWG) is a key component of efficient heifer rearing, in terms of reducing age at first calving as well as future production, health and survival. While DLWG is impacted by multiple factors, one of the main factors is milk feeding, with whole milk (WM) having the optimal composition to maximise DLWGs in heifers. Commercial milk replacers (CMR) have been shown to be highly variable in terms of formulation balance, raw material inclusion and nutrient digestibility. Energized calf milk (ECM) has been designed to have a similar osmolality and lower lactose level than whole milk (WM), resulting in a decreased risk of osmotic diarrhoea. ECM has been designed to have a higher fat content than standard CMRs, with increased digestibility and improved solubility of fats as a result of homogenisation and encapsulation of the fats. Higher levels of fat in CMR has been reported to have potential health benefits, increased DLWG and increased future milk yields. One of the downsides of ECM is the higher price per tonne; however combined with the higher feed conversion efficiency of pre-weaned calves, ECM can result in increased DLWG and potentially decreased health issues and therefore the price per kg weight gain can make ECM an economically viable option, before considering the potential longer-term benefits.

Relationship between Temperament and Stage of Lactation, Productivity and Milk Composition of Dairy Cows.

Simple SummaryCattle temperament can be described as a response to changes in the environment and is crucial for successful herd management using innovative technologies. Despite the economic aspects of animal productivity and welfare, there is still a lack of objective evidence for a wider use of temperament in dairy cattle breeding programmes. The aim of this study was to evaluate the relationship between cow temperament and milk indices describing cow productivity, metabolic status and mastitis resistance. The coefficient of heritability of temperament was determined. Only a small part of the phenotypic changes in this indicator in the analysed population was associated with genetic factors; however, the correlation of cow temperament with milk lactose and somatic cells suggests that temperament could be used in sustainable breeding programmes, giving priority to animal welfare and health. A statistically significant decrease in temperament scores with increasing lactation periods was only found in primiparous cows. It is also argued that changes in milk production, milk composition and quality associated with mastitis and a cow’s metabolic status should be taken into account when assessing the cow’s temperament, as these factors can affect the welfare and behaviour of an animal, and therefore the expression and intensity of their reaction to their environment.The aim of this study was to assess the relationship between temperament and milk performance in cows at different stages of lactation, describing their productivity, metabolic status and resistance to mastitis. This study showed that with increasing lactation, cows’ temperament indicators decreased (p < 0.001) and they became calmer. The highest temperament score on a five-point scale was found in cows between 45 and 100 days of lactation. In the group of pregnant cows, we found more cows (p = 0.005) with a temperament score of 1–2 compared with non-pregnant cows A normal temperament was usually detected in cows with lactose levels in milk of 4.60% or more and when the somatic cell count (SCC) values in cow milk were <100,000/mL and 100,000–200,000/mL, with a milk fat-to-protein ratio of 1.2. A larger number of more sensitive and highly aggressive cows was detected at a low milk urea level. In contrast to a positive phenotypic correlation (p < 0.05), this study showed a negative genetic correlation between the temperament of cows and milk yield (p < 0.001). Positive genetic correlations between temperament scores and milk somatic cells (p < 0.001) and milk fat-to-protein ratio (p < 0.05) were found to indicate a lower genetic predisposition in cows with a calmer temperament to subclinical mastitis and ketosis. On the other hand, the heritability of temperament (h2 = 0.044–0.100) showed that only a small part of the phenotypic changes in this indicator is associated with genetic factors.

Milk Lactose as a Biomarker of Subclinical Mastitis in Dairy Cows.

Simple SummaryEarly bovine subclinical mastitis detection may improve treatment strategies and milk yield and reduce the use of antibiotics. Scientific research is therefore focusing on the identification of new and less expensive biomarkers. One of the biomarkers with the greatest potential is milk lactose. To establish whether lactose could be used as an indicator for subclinical mastitis, milk samples from seventy-two herds were screened for bovine subclinical mastitis agents. This study evaluated the prevalence of subclinical mastitis pathogens, their seasonal occurrence, and the relationship with milk lactose concentration. Milk samples were mostly found to be infected with mixed microbiota, coagulase-negative Staphylococcus and Staphylococcus aureus. Yeast, Enterococcus spp. and coliform bacteria such as Escherichia coli were found during the outdoor grazing period. Increases in somatic cell count and decreases in lactose concentration were directly related to the presence of bovine subclinical mastitis agents. These findings suggest that changes in lactose content could be tracked as a diagnostic method in subclinical mastitis prevention in cows.Bovine subclinical mastitis can cause great harm to dairy herds because of its negative impact on milk production and quality and cow health. Improved diagnostic tools are needed to maximise the control of subclinical mastitis distribution and ensure the high quality of milk as an industrial product. Between 2015 and 2020, seventy-two dairy herds were screened for bovine subclinical mastitis causative agents to identify the relationship between seasons, lactose levels and subclinical mastitis infection. The predominant species found in the milk samples were mixed microbiota, coagulase-negative Staphylococcus and Staphylococcus aureus. Yeasts were found exclusively in autumn, while Enterococcus spp. and Escherichia coli were only found in summer and autumn. A negative correlation was detected between milk lactose and number of somatic cells in milk (−0.471; p < 0.001). The lactose levels in milk were closely associated with the prevalence (%) of subclinical mastitis pathogens, such as Streptococcus agalactiae (y = −1.8011x + 10.867, R2 = 0.9298), Staph. aureus (y = −3.5216x + 25.957, R2 = 0.8604) and other Streptococci (y = −0.5956x + 7.6179, R2 = 0.6656). These findings suggest that milk lactose may be used as a biomarker of suspected udder inflammation in modern health prevention programmes for cows to reduce the prevalence of subclinical mastitis pathogens in dairy cattle herds.

Rule Discovery in Milk Content towards Mastitis Diagnosis: Dealing with Farm Heterogeneity over Multiple Years through Classification Based on Associations.

Simple SummaryInvisible (subclinical) mastitis decreases milk quality and production. Invisible mastitis is linked to an increased use of antimicrobials. The risk of the emergence of antimicrobial-resistant bacteria is a major public health concern worldwide. Therefore, early detection of infected cows is of great importance. Machine learning has opened a new avenue for early mastitis prediction based on simple and accessible milking parameters, such as milk volume, fat, protein, lactose, electrical conductivity (EC), milking time, and milking peak flow. However, farm heterogeneity is a major challenge where multiple patterns can predict mastitis. Here, we employed a classification based on associations and scaling approach for multiple pattern discovery over multiple years. The approach we have developed helps to address farm heterogeneity and generalise machine learning-based diagnosis of mastitis worldwide.Subclinical mastitis, an economically challenging disease of dairy cattle, is associated with an increased use of antimicrobials which reduces milk quantity and quality. It is more common than clinical mastitis and far more difficult to detect. Recently, much attention has been paid to the development of machine-learning expert systems for early detection of subclinical mastitis from milking features. However, differences between animals within a farm as well as between farms, particularly across multiple years, are major obstacles to the generalisation of machine learning models. Here, for the first time, we integrated scaling by quartiling with classification based on associations in a multi-year study to deal with farm heterogeneity by discovery of multiple patterns towards mastitis. The data were obtained from one farm comprising Holstein Friesian cows in Ongaonga, New Zealand, using an electronic automated monitoring system. The data collection was repeated annually over 3 consecutive years. Some discovered rules, such as when the milking peak flow is low, electrical conductivity (EC) of milk is low, milk lactose is low, milk fat is high, and milk volume is low, the cow has subclinical mastitis, reached high confidence (>70%) in multiple years. On averages, over 3 years, low level of milk lactose and high value of milk EC were part of 93% and 83.8% of all subclinical mastitis detecting rules, offering a reproducible pattern of subclinical mastitis detection. The scaled year-independent combinational rules provide an easy-to-apply and cost-effective machine-learning expert system for early detection of hidden mastitis using milking parameters.

Metabolomic and Lipidomic Approaches to Evaluate the Effects of Eucommia ulmoides Leaves on Milk Quality and Biochemical Properties.

Eucommia ulmoides leaves (EUL) contain a variety of natural bioactive compounds including chlorogenic acid, geniposide acid, and aucubin. These bioactive chemicals improve immune function and regulate lipid metabolism. The aim of this study was to investigate the effects of EUL on the biochemical properties of milk. Twenty Holstein dairy cows were randomly allocated to two groups fed a control (CTR, diet without EUL, n = 10) or EUL (diet containing 3% EUL, dry matter, n = 10) diet for 55 d. At the end of the experimental period (d 55), milk samples were collected and analyzed to determine their composition. Though levels of milk fat, protein, lactose, and total milk solids were similar between the groups, small molecules, metabolites, lipids, and cytokines differed. Compared with the CTR group, the EUL group had an improved cluster of differentiation (CD)4/CD8 ratio (P < 0.05) and lower interleukin (IL)-8 and IL-6 content (P < 0.05). Metabolomics analysis identified 14 metabolites including 7Z, 10Z, 13Z, 16Z, 19Z-docosapentaenoic acid (FC = 3.129), adrenic acid (FC = 2.830), and eicosapentaenoic acid (FC=1.685) as having significantly increased in the EUL group (P < 0.05) while 11 metabolites, including indole-2-carboxylic acid (FC = 0.636), cholic acid (FC = 0.430), and creatine (FC = 0.784) had significantly decreased (P < 0.05). Based on a constructed metabolome map, linoleic acid metabolism had the highest impact value for EUL. A total of 21 lipid classes and 1,094 lipid species were detected in the milk by lipidomic analysis, among which 40 differed significantly between the CTR and EUL groups. The present findings showed that the EUL altered milk composition. Correlation analysis showed that 7Z, 10Z, 13Z, 16Z, 19Z-docosapentaenoic acid, adrenic acid, and eicosapentaenoic acid levels were negatively correlated with those of the inflammatory factors IL-6 and IL-8 (P < 0.05), indicating that EUL improved milk quality by reducing inflammatory factors and increasing the CD4/CD8 ratio. Overall, our data demonstrate that EUL had positive effects on milk antioxidant parameters, immune indices, and micro-composition metabolism, thereby improving milk quality.

Characterizing Maillard reaction kinetics and rheological changes in white chocolate over extended heating.

Molten white chocolate held at high temperatures for extended periods of time undergoes thickening and nonenzymatic browning reactions. Lactose and milk proteins participate in Maillard browning, which occurs more rapidly at higher temperatures. Crystallization of amorphous lactose and high temperature contribute to rheological changes over heating. In the present study, five white chocolates of varied compositions were sampled over time at different temperatures. White chocolates containing amorphous lactose showed increases in complex viscosity, while chocolates with crystalline or no lactose showed no change in rheological properties. Maillard browning was measured through both colorimetry and spectrophotometric analysis of brown pigments. Both markers showed the greatest browning for Nonfat dry milk (NFDM)-containing systems. Chocolates containing no NFDM (milk protein isolate, MPI, or crystalline lactose) showed no change in absorbance after clarification, but some browning in colorimetry results, likely due to residual amorphous lactose in the MPI or increased mobility of lactose from crystals at high temperatures. The evolution of fluorescent intermediates was visualized using fluorescence spectroscopy, revealing that these intermediates were formed prior to colored end stage products and were consumed as the reaction approaches completion. An excess of lactose in the system meant reducing sugar declines were relatively small throughout. Kinetic models were created to determine the influence of chocolate composition and temperature on thickening as related to complex viscosity (first order) and browning via colorimetry and absorbance (pseudo-zero order). Both thickening rate and Maillard reaction rates were faster in chocolates with greater levels of amorphous lactose and when held at higher temperatures. PRACTICAL APPLICATION: So-called "golden chocolate" is white chocolate that has been held at warm temperatures for a period of time to undergo Maillard browning. However, thickening of the chocolate during heating can cause processing problems. In this study, viscosity changes are correlated with Maillard browning kinetics to help chocolate manufacturers find optimal conditions for creating new products.

Crude protein and lactose effects on performance, intestinal and immune function of piglets fed diets without antimicrobials growth promoters

The present study was carried out to evaluate the effects of crude protein (CP) and lactose (LAC) levels on performance, intestinal morphology and gene expression associated to epithelial integrity and activation of the immune system of piglets fed antimicrobial free diets. A total of 120 weaned piglets with initial weight 7.9 ± 0.9 kg were assigned to a randomized block design, in a 2 × 3 factorial arrangement (20.0 and 24.0% CP and 8.0%, 12.0%, and 16.0% LAC), with 10 replicates. The reduction of dietary protein from 24.0 to 20.0% was based on concept of ideal protein, keeping the same SID lysine values. Piglets fed 24.0% CP had higher average daily feed intake (ADFI). Diets containing 12.0 or 16.0% LAC resulted in higher ADFI and average daily gain of piglets compared to 8.0% LAC. Pigs fed 12.0% LAC diets had greater final body weight than those fed 8.0 and 16.0% LAC diets. Piglets consuming 20.0% CP diets had lower SUN. Piglets fed 12.0 or 16.0% LAC diets had higher duodenum and ileum villous height (VH). Interactions were observed for duodenum, jejunum and ileum crypt depth (CD) and duodenum and ileum VH:CD ratio. Piglets fed 24.0% CP diet with 12.0 or 16.0% LAC had lower duodenum and ileum CD, and higher duodenum and ileum VH:CD ratio than those fed 8.0% LAC. At 24.0% CP, piglets fed 16.0% LAC had lower expression of Hp and ZO-1. Concentration of 12.0% LAC in the diet improves performance of piglets from 21 to 35 days of age regardless CP content. The inclusion of 12.0 or 16.0% LAC in the diet promotes improvements in intestinal morphology, which are more evident in the diet with 24.0% CP. In addition, increasing LAC content in the diet with 24.0% CP decreases the activation of the immune system and reduces the permeability of the intestinal epithelium.

Laboratory signs of carbohydrate malabsorption in early age children with rotavirus infection

The aim – to determine the laboratory manifestations of carbohydrate malabsorption syndrome in the dynamics of rotavirus infection in early age children and to identify the factors that influence its severity. Materials and methods. The study included 60 breastfed children aged 1–24 months with rotavirus infection, who underwent pH-metry of feces, semi-quantitative determination of total carbohydrates (Benedict’s method), lactose (Malfatti method) and glucose (test systems Glucophan) in feces on the 2nd, 3rd, 5th, 7th and 10th days of the disease. Results. Carbohydrate malabsorption syndrome was observed in 98.3% of patients. The level of fecal carbohydrates increased on the second-third day to a clinically significant 0.50 [0.20; 1,50] %, reached its maximum in the midst of the disease – from the fifth to the seventh day (0.75 [0.50; 1.65] % and 0.87 [0.40; 1.65] %, respectively), decreasing during convalescence to 0.50 [0.20; 1.50] % (P &lt; 0.05 relative to the 10th day), but remained elevated in 81.7 % of patients (P &lt; 0.05 relative to healthy children). Lactase deficiency and glucose malabsorption (P &lt; 0.05 relative to healthy children) were observed throughout the RVI period. At all stages of RVI there was a strong direct correlation between the total level of carbohydrates and lactose in the feces (on the second, third, fifth, seventh and tenth days r = 0.91; r = 0.86; r = 0.91; r = 0.89, respectively). The age dependence of the severity of laboratory indicators of carbohydrate malabsorption was established. Children in the first 6 months had the highest maximum levels of carbohydrates and fecal lactose – 1.75 [1.00; 2.00] % and 3.50 [2.00; 4.00] + respectively (P &lt; 0.05 relative to 12–24 months children) and significantly higher values of these indicators in the dynamics of RVI (P &lt; 0.05 relative to 12–24 months children) for the second-third, fifth and the tenth day). Children with concomitant food allergies, atopic dermatitis and iron deficiency anemia had 2.0 and 1.5 times higher maximum levels of carbohydrates and lactose in the stool, respectively (P &lt; 0.05), as well as higher values of these indicators in the dynamics of the disease – on the third and fifth days (P &lt; 0.05). Conclusions. The vast majority of young patients with rotavirus infection have carbohydrate malabsorption syndrome, which occurs from the first days of the disease and is most pronounced on the fifth to seventh day (P &lt; 0.05 relative to the 10th day), realized mainly due to lactase deficiency. The most pronounced carbohydrate malabsorption syndrome and lactase deficiency in the dynamics of the disease are present in children of the first six months of life. Factors that increase the severity of carbohydrate malabsorption due to secondary lactase deficiency in the acute period of rotavirus infection are concomitant food allergies, atopic dermatitis and iron deficiency anemia.

Use of recycled co-products from the food industry: Effects on nutrient digestibility and growth performance in pigs from 7 to 23 kg

We studied the effects of the inclusion of recycled co-products from the food industry (yogurt, milk, cheese and baby foods) in diets for pigs weaned at 25 days of age. From day 1–21 of the experiment (Phase I), 8 treatments were organized as a 2 × 4 factorial with 2 levels of lactose (70 and 100 g/kg) and 4 diets differing in the food co-products used. The control diet was based on cooked wheat, fish meal, and dried whey, without any food co-product. Diets D2 and D3 included 150 g/kg lactal (yogurt and milk sprayed onto a cereal carrier) or 150 g/kg lactal-cheese (yogurt, milk and cheese sprayed onto the same carrier) in substitution of dried whey and fish meal of the control. Diet D4 was similar to D3 but in addition to 150 g lactal-cheese, included 200 g/kg of recycled baby foods (composed primarily of hydrolysed and processed cereals) in substitution of cooked wheat. From day 22–35 (phase II) all pigs received a common cereal-soybean meal diet. In phase I, an increase in the lactose content in the diet increased average daily feed intake (ADFI; P < 0.05) and average daily gain (ADG; P < 0.01). The inclusion of food co-products in the diet, however, did not affect ADG. At 14 days post-weaning, the total tract apparent digestibility of nutrients improved as the lactose content of the diet increased, and was greater in pigs fed D4 than in pigs fed any of the other diets (P < 0.05). In phase II, pig growth was not affected by previous dietary treatment. For the entire experiment, ADFI tended to increase (P = 0.065) in pigs fed the high lactose diets in phase I and was higher (P < 0.05) in pigs fed the D4 diet in phase I than in pigs fed the D2 diet, with pigs fed the other diets being intermediate. The ADG and the gain to feed ratio, however, were not affected. Cumulatively, post-weaning diarrhoea was not affected by the level of lactose or the type of diet used. In conclusion, increasing the lactose content of the diet after weaning from 70 to 100 g/kg improved pig performance. The food co-products tested can be used successfully in substitution of high quality ingredients, such as dried whey, fish meal and heat processed cereals, in diets for weanling pigs, without any negative effect on growth performance.

Sezonowe różnice w parametrach jakościowych mleka z tradycyjnego małego gospodarstwa rodzinnego

This research aimed to determine the hygienic quality, physicochemical properties and technological suitability of milk obtained in an extensive, small family farm in western Poland in the spring-summer (grazing) and autumn-winter (indoor) seasons. The farm was operated in the traditional manner where animals spend 7/24 on the pasture in the spring-summer season. The study was performed on forty-eight samples of bulk tank milk collected once a week over one year from 17 cows of the old local Polish black and white lowland breed. Milk was tested for somatic cell count, total bacterial count, basic composition, density, vitamin C content, rennet coagulation time, pH and colour in the CIE L*a*b* system. In the autumn-winter season, a higher somatic cell count, higher protein, fat and lactose levels, longer coagulation time and lower colour parameter a* values were found compared with the spring-summer period. However, no differences as regards the colour parameters L* and b* and vitamin C content were observed between the seasons. Highly significant negative correlations between the colour of the milk and the total bacterial count and somatic cell count were found (P ≤ 0.01). High somatic cells count in studied milk highlights that mastitis and milking hygiene are still a challenging task in small family farms.

Effect of partial exchange of lactose with fat in milk replacer on ad libitum feed intake and performance in dairy calves

Compared with Holstein whole milk, commercial milk replacers (MR) for calves deliver relatively high levels of lactose and low levels of fat, and protein levels are rather comparable, resulting in a lower energy density and energy-to-protein ratio of the diet. Thus, the objective of this study was to determine the effects of partially exchanging lactose with fat in MR on voluntary feed intake, growth performance, and feeding behavior. Thirty-two male Holstein calves (2.1 ± 0.16 d of age, 46.4 ± 0.77 kg of body weight; BW) were assigned to 16 blocks of 2 calves per block based on arrival date and serum IgG. Within each block, calves were randomly assigned to 2 treatments: a high-lactose MR (HL; 17% fat; 44% lactose), or a high-fat MR (HF; 23% fat; 37% lactose). Lactose was exchanged by fat on a weight per weight basis, resulting in a 6% difference in metabolizable energy density per kilogram of MR. The experiment was divided into 3 phases: preweaning (P1; 0-35 d), weaning (P2; 36-56 d), and postweaning (P3; 57-84 d). For the first 2 wk of P1, calves were individually housed, fed their respective MR ad libitum through teat buckets, and provided access to water. At 14.2 ± 0.5 d of age, calves were group-housed (4 blocks/pen, 8 calves) and housed in group pens for the remainder of the study. In the group pens, calves were fed ad libitum MR, starter feed, chopped wheat straw, and water via automated feeders. During P2, calves were gradually weaned until complete milk withdrawal by 57 d and then monitored until 84 d (P3). Measurements included daily intakes and feeding behavior (rewarded and unrewarded visits), weekly BW and body measurements, and biweekly blood samples. Increasing fat content at the expense of lactose decreased MR intake during P1 by 15% (HL = 1.32 ± 0.04; HF = 1.17 ± 0.04 kg of dry matter per day), whereas total starter intake was not affected by MR composition. Once MR was restricted during P2, HL calves were reported to have more unrewarded visits to the automatic milk feeder than HF calves (11.9 ± 0.95 vs. 8.4 ± 1.03 visits/d, respectively). Crude protein intake was higher for HL calves during P1 (352.1 ± 11.2 vs. 319.6 ± 11.6 g/d), which was attributed to the higher intake of MR during that period, and metabolizable energy intake and protein-to-energy ratio remained comparable between treatments. Plasma cholesterol and nonesterified fatty acids levels were higher in HF calves as a consequence of the diet. Nevertheless, final BW (84 d) did not differ between treatments. Overall, calves fed ad libitum seemed to regulate their intake of MR based on its energy density, without significant effects on solid feed intake and overall growth.