Cross-sectional Method of Sugar Content and Essential Nutrients in Commercial UHT Milk for Toddlers in Indonesia

<p>The extended shelf life and undemanding storage requirements of UHT (ultra high temperature) milk make it the most consumed fluid milk in Brazil. The thermal treatment to which UHT milk is subjected alters casein micellar structure, leading to protein sedimentation and age gelation. Therefore, the current legislation allows the addition of up to 0.1% stabilizing salts (sodium citrate and/or sodium phosphates) in milk. The adding of stabilizing salts hinders the possibility of inclusion of freezing point and density as quality parameters of UHT milk. Evaluation of freezing point is the main test to detect adulteration of milk with water; however, addition of stabilizers alters its results. This study aimed to measure the alterations in freezing point and density caused by stabilizers in samples of pasteurized milk added with sodium citrate or sodium phosphates, in order to propose standards for freezing point and density for UHT milk. For this purpose, 16 aliquots of milk were prepared in nine repetitions with different concentrations (0%, 0.001%, 0.01%, 0.05%, 0.075%, 0.1%, 0.125%, and 0.15%) of sodium citrate or a commercial mix of sodium mono-, di- and triphosphate. The density and freezing point of all aliquots were tested. As expected, addition of stabilizers lowered the freezing point of milk. Addition of 0.1% citrate and commercial mix promoted an average reduction of –0.021°H (± 0.001) and –0.017°H (± 0.002) in freezing point, respectively. However, no significant change in the density of milk was observed. Given that UHT milk industry usually adds the maximum limit of 0.1% of stabilizers in order to obtain proper effect, the interval from –0.572°H to –0.545°H can be suggested as the standard for freezing point to UHT milk. However, as the addition of stabilizers caused no significant change in the density of UHT milk, the density parameter of raw and pasteurized milk in the range from 1.028 g.mL-1 to 1.034 g.mL-1 could be applied to UHT milk.</p>

<p>The extended shelf life and undemanding storage requirements of UHT (ultra high temperature) milk make it the most consumed fluid milk in Brazil. The thermal treatment to which UHT milk is subjected alters casein micellar structure, leading to protein sedimentation and age gelation. Therefore, the current legislation allows the addition of up to 0.1% stabilizing salts (sodium citrate and/or sodium phosphates) in milk. The adding of stabilizing salts hinders the possibility of inclusion of freezing point and density as quality parameters of UHT milk. Evaluation of freezing point is the main test to detect adulteration of milk with water; however, addition of stabilizers alters its results. This study aimed to measure the alterations in freezing point and density caused by stabilizers in samples of pasteurized milk added with sodium citrate or sodium phosphates, in order to propose standards for freezing point and density for UHT milk. For this purpose, 16 aliquots of milk were prepared in nine repetitions with different concentrations (0%, 0.001%, 0.01%, 0.05%, 0.075%, 0.1%, 0.125%, and 0.15%) of sodium citrate or a commercial mix of sodium mono-, di- and triphosphate. The density and freezing point of all aliquots were tested. As expected, addition of stabilizers lowered the freezing point of milk. Addition of 0.1% citrate and commercial mix promoted an average reduction of –0.021°H (± 0.001) and –0.017°H (± 0.002) in freezing point, respectively. However, no significant change in the density of milk was observed. Given that UHT milk industry usually adds the maximum limit of 0.1% of stabilizers in order to obtain proper effect, the interval from –0.572°H to –0.545°H can be suggested as the standard for freezing point to UHT milk. However, as the addition of stabilizers caused no significant change in the density of UHT milk, the density parameter of raw and pasteurized milk in the range from 1.028 g.mL-1 to 1.034 g.mL-1 could be applied to UHT milk.</p>

Brazilian Ultra High Temperature (UHT) milk consumption has increased during the last decade from 187 to 4,200 million liters. In the continuous UHT process, milk is submitted for 2-4 s to 130-150ºC, in a continuous flow system with immediate refrigeration and aseptical packing in hermetic packages. This research had the purpose to verify the incidence of B. cereus species from the B. cereus group, in UHT milk. In 1998 high indexes of these organisms were reported, reaching 34.14% of the analyzed samples. Beyond this fact, there was the need to establish methods and processes adjusted for correct identification of B. cereus. Thus, commercial sterility tests of 6,500 UHT milk packages were investigated in two assays, after ten days incubation at 37ºC and 7ºC to germinate all possible spores and/or to recuperate injured vegetative cells followed by pH measurement. Samples (1,300 packages each) from five Brazilian UHT plants of whole UHT milk processed by direct steam injection, packaged in carton were investigated for the presence of Bacillus cereus through phenotypic and genetic (PCR) tests. Values of pH were different for the samples, ranging between 6.57 and 6.73. After storage of the samples, only four packages with pH measurement below the lower limit of 6.5 were found and analyzed for the presence of B. cereus. This organism was not detected in any of the samples indicating that the five Brazilian UHT milk processors control pathogenic microorganisms and it can be said that the consumption of UHT milk does not present safety problems to consumers. Fourier Transform Infrared Spectroscopy (FTIR) and PCR tests were efficient and must be adopted to confirm the biochemical series for B. cereus.

The objective of the present study was to illustrate the changes in physicochemical properties in ultra-high temperature (UHT) milk packed into a pouch and Tetra Brik during storage. UHT milk samples were kept at 5 and 25 °C for 3 months and regularly analyzed monthly. During storage, significant increases (p < 0.05) in titratable acidity (TA), water-soluble nitrogen (WSN), and non-protein nitrogen (NPN) when UHT milk was packed into pouch versus Tetra Brik and stored at 25 versus 5 °C. Neither type of packaging nor storage temperature affect pH values during storage. Spore-forming bacterial (SFB) count was always higher in UHT milk packed into pouch versus Tetra Brik. Refrigerated storage kept UHT milk without detectable SFB compared to UHT milk held at 25 °C. Pouch packages were responsible for the migration of phthalate derivatives [dimethyl phthalate "DMP", diethyl phthalate "DEP", dibutyl phthalate "DBP", and di-(2-Ethylhexyl) phthalate "DEHP"] into milk with significantly greater levels than milk filled into Tetra Brik. The total sensory scores were decreased significantly during storage, which was more pronounced in UHT milk filled into pouch versus Tetra Brik or stored at 25 °C versus 5 °C. It is concluded that UHT milk filled into Tetra Brik stored at 5 and 25 °C is better in terms of quality and safety indexes than such filled into a pouch.

Hydrolysis of lactose in milk by β-galactosidase from immobilized bacterial cells has the potential to alleviate the problem of lactose intolerance. The present study was aimed to immobilize cells of L. plantarum strain B134 and evaluate their efficiency in hydrolyzing lactose in ultra high temperature (UHT) milk. Immobilized cells were generated by mixing cell suspensions with solutions of sodium alginate and calcium chloride. The β-galactosidase activity of the immobilized cells was tested by determining their ability in hydrolyzing lactose in UHT milk (whole milk and skimmed milk). Results showed that cells of L. plantarum strain B134 were entrapped optimally using a combination of 1 % sodium alginate, 100 mM calcium chloride and 12 % w/v cell suspension. The highest β-galactosidase activity was achieved at pH 6.5 and a temperature of 45 ºC for 5 minutes incubation time. The immobilization efficiency achieved was 28.95 %. The immobilized cells could reduce lactose by up to 85.45 % in UHT whole milk and 91.26 % in UHT skimmed milk. The times required for that reduction of lactose in UHT whole milk and UHT skimmed milk were 12 hours and 9 hours respectively. The immobilized cells could be re-used up to 4 times for efficient lactose hydrolysis for both types of milk. Therefore, immobilized cells of L. plantarum B134 have the potential to be used for lactose hydrolysis in UHT milk.

Proteomics and peptidomics of variations in protein profiles of UHT milk following non-enzymatic compared to enzymatic processes.

The high content of α-galactooligosaccharide in mung beans has the potential for supporting the growth of Lactic Acid Bacteria (LAB), therefore it can be developed as fermented plant-based milk that substituted Ultra High Temperature (UHT) milk. The purposes of this research is to investigate the effectiveness of LAB Lactococcus lactis NBRC 12007 in the fermentation process of mung bean milk and to observe the quality differences of fermented mung bean milk with UHT milk. Previously, preparations were made for starter L. lactis NBRC 12007 in MRSB medium and then sub cultured to UHT milk. Furthermore, 3% of the culture was inoculated into each of the mung bean milk substrate and UHT milk as a starter for the fermentation process and incubated for 24 hours at 37oC. During this process, the effectiveness of LAB was tested (total cell, total acid, total protein, pH, antibacterial) and the quality test of fermented products (organoleptic and physical). Based on total cells, total acid, total protein, pH, and antibacterial test findings, fermented mung bean milk products had a higher value than UHT milk products. During the process, it was proven that L. lactis NBRC 12007 had high effectiveness in producing and improving the quality of fermented mung bean milk compared to UHT milk. It is assumed that the content of oligosaccharides supports the growth of LAB and the fermentation process.

The role of key process steps on microstructural organisation of fat globules and lipid profiles in UHT milk processed in a pilot plant unit

Enhancing Ultra-High Temperature Milk Quality: A Novel Approach to Microbial Contamination Detection Using the BD BACTEC™ FX System

With the increasing awareness of people about food consumption, the demand of supplying aseptically packed food such as ultra-high temperature (UHT) milk is increasing. Some native and microbial proteases are relatively heat stable and cannot be inactivated during UHT treatment. The traces of these enzymes are responsible for various proteolytic changes (e.g. age-gelation and bitterness) in the stored UHT milk. There are various methods reported in the literature to measure proteolysis in milk and milk products like UHT milk. All the methods have their own merits and demerits and depending upon requirement, one has to select one or more methods for the measurement of proteolysis. The comparison of these methods are carried out in this paper. Keywords: UHT milk, proteolysis, age-gelation, proteolysis assessment Cite this Article Keyursinh D. Vaghela, Bhavesh N. Chaudhary, Bhavbhuti M. Mehta. A Review on Proteolysis Rate in UHT Milk: Its Mechanism, Pattern, Assessment and Enzymatic Changes during Storage. Research and Reviews: Journal of Dairy Science and Technology. 2017; 6(3): 1–16p.

The aim of this work was to evaluate the volatile profile of whole milk treated by ultra‐high‐pressure homogenization (UHPH) at 300 MPa with inlet temperature (Ti) = 65, 75, and 85 °C, comparing the results to Ultra High Temperature (UHT) milk. From the results, in UHT milk, ketones and dimethyl thrisulfide concentration was higher than in any other sample. On the contrary, the concentration of aldehydes in UHPH‐treated milk samples was higher than the concentration detected in heat‐treated samples. Principal components analysis explained the variations in the observed responses, presenting well‐defined and separated groups. UHPH represents a suitable alternative to reduce cooked‐related compounds presented in heat‐treated milk.Practical applicationsThis study provides more information regarding ultra‐high‐pressure homogenization (UHPH) as an emerging technology with industrial applications. In this case, the UHPH application was able to reduce the amount of volatile compounds such as ketones related to cooked flavor in heat treatments at high intensity, such as UHT processing. For this, several UHPH‐proved safety conditions were compared to the volatile profile obtained in UHT milk.

Ultra high temperature (UHT) milk is a product that is widely consumed because of its practicality and hygiene. PT XYZ is one of the industries that produces UHT milk with chocolate and strawberry flavors. Based on company records, there are variations in the protein content of the two products. The purpose of this study was to determine the average protein content of chocolate and strawberry milk on the control chart and to develop a cause-and-effect diagram to determine the factors that triggered variation in protein levels in PT XYZ's chocolate milk and strawberry milk. The research data was obtained from company records, which were then analyzed using MR control charts and fishbone diagrams. The results showed that there were values that were outside the control limits, both in the chocolate and strawberry flavor variants. The cause of the variability in the value of protein content in UHT milk in both chocolate and strawberry flavors comes from 4 factors. The machine factor is in the form of machine checking, which is still curative. The human factor is a lack of human resources and the absence of regular employee training. The factor of the method of using materials that are still manual Material factors are in the form of non-uniformity of sources and quality of raw materials for fresh milk from suppliers, and differences in quality and type of raw materials (between fresh milk and recombined milk).

Ultra high temperature (UHT) milk is a product that is widely consumed because of its practicality and hygiene. PT XYZ is one of the industries that produces UHT milk with chocolate and strawberry flavors. Based on company records, there are variations in the protein content of the two products. The purpose of this study was to determine the average protein content of chocolate and strawberry milk on the control chart and to develop a cause-and-effect diagram to determine the factors that triggered variation in protein levels in PT XYZ's chocolate milk and strawberry milk. The research data was obtained from company records, which were then analyzed using MR control charts and fishbone diagrams. The results showed that there were values that were outside the control limits, both in the chocolate and strawberry flavor variants. The cause of the variability in the value of protein content in UHT milk in both chocolate and strawberry flavors comes from 4 factors. The machine factor is in the form of machine checking, which is still curative. The human factor is a lack of human resources and the absence of regular employee training. The factor of the method of using materials that are still manual Material factors are in the form of non-uniformity of sources and quality of raw materials for fresh milk from suppliers, and differences in quality and type of raw materials (between fresh milk and recombined milk).

The impact of different temperatures on spore count and browning of UHT milk over a long storage period

Cooked or sulfurous off-flavour caused by volatile sulfur compounds (VSCs) limits acceptance of ultra-high temperature (UHT) milk in some parts of the world. Therefore, the concentrations of VSCs in UHT milk over 16 weeks of storage were studied and compared with those in pasteurised milk. The major VSCs contributing to the cooked flavour were identified using solid-phase microextraction and gas chromatography with pulsed flame photometric detection. Nine VSCs were detected in commercial indirectly processed UHT skim and whole milk. These were hydrogen sulfide, carbonyl sulfide, methanethiol, dimethyl sulfide, carbon disulfide, dimethyl disulfide, dimethyl sulfoxide, dimethyl sulfone and dimethyl trisulfide. An additional VSC was detected but not identified. The concentrations of hydrogen sulfide, methanthiol, dimethyl sulfide and dimethyl trisulfide were initially higher than their reported threshold values indicating their importance in milk flavour, especially cooked flavour. However, they decreased slowly during storage to levels below their threshold values. This decrease corresponded to a decrease in dissolved oxygen level. Four VSCs, carbon disulfide, dimethyl sulfide, dimethyl sulfoxide and dimethyl disulfide, were detected in pasteurised milk; however, their concentrations were lower than their reported threshold values. This paper puts into perspective the significance of VSCs in the flavour of UHT and pasteurised milk, both initially and during storage, and indicates the period of storage for minimisation of cooked flavour in UHT milk.