Milk Pasteurization Process Research Articles

A Ratiometric Molecularly Imprinted Sensor for Visual Detection and Removal of α-Dicarbonyl Compounds Based on Biomass Carbon Dot-Embedded Fluorescent Covalent Organic Frameworks.

α-Dicarbonyl compounds (α-DCs) are important intermediate products during the thermal processing of foods and are closely related to the development of chronic diseases in the human body. However, there remains a significant gap in the availability of rapid detection methods for α-DCs. So, the ratiometric molecularly imprinted polymers (RCDs@GCOFs@MIPs) based on red-emitting biomass carbon dots (RCDs) and green-emitting fluorescent covalent organic frameworks (GCOFs) were constructed for the detection and removal of α-DCs in food processing. The ratiometric fluorescent sensors exhibited satisfactory detection and had good spiking recoveries in milk samples. And the excellent inhibition of pyrraline (PRL) by ratiometric fluorescent sensors was verified by simulating the milk pasteurization process. In addition, rapid onsite detection of α-DCs was achieved by recognizing the RGB value of the ratiometric fluorescence sensors via the smartphone. The ratiometric fluorescence sensors presented a new strategy for detecting and removing hazardous substances in food processing.

Enhancing low‐temperature long‐time milk pasteurization process with a C4.5 algorithm‐driven AIoT system for real‐time decision‐making

AbstractThis research is driven by the imperative to improve the milk pasteurization process's efficiency and safety within the Industry 5.0 framework. It introduces the artificial intelligence of things (AIoT) into the pasteurization system and focuses on deploying the C4.5 algorithm, anticipated to render precise real‐time decisions by analyzing critical temperature and duration data essential for the low‐temperature long‐time (LTLT) pasteurization technique. Test results indicate that the C4.5 model is highly effective, demonstrating nearly perfect metrics with a precision of .78, a recall of .77, and an F1‐score of .73, while achieving an overall algorithm accuracy of .76. In terms of heating control, the double jacket method tested on a 300‐L system proved the control design's capability to quickly reach and maintain desired temperatures, hitting the set‐point within 70 min. However, it was observed that systems with larger capacities took longer to reach the set‐point, suggesting a potential for further optimization. The findings affirm that integrating AIoT into control systems can significantly enhance process efficiency and effectiveness, consistent with the goal of incorporating sophisticated technological solutions in the food sector.Practical ApplicationsThe article “Enhancing Low‐Temperature Long‐Time Milk Pasteurization Process with a C4.5 Algorithm‐Driven AIoT System for Real‐Time Decision‐Making” explores an AIoT system's potential to revolutionize the dairy industry's pasteurization methods. This system promises enhanced efficiency by optimizing energy and time, thereby reducing costs. It ensures superior quality control through continuous monitoring, maintaining nutritional integrity and safety. The high automation level minimizes human error and operational demands, while predictive maintenance forecasts prevent downtime. The system's scalability supports production expansion with minimal resource increase. Moreover, it guarantees product traceability and compliance with food safety regulations. The generated data offers insights for further supply chain optimizations. This integration of AI and IoT thus presents significant advancements in process management, quality assurance, and scalable operations for the dairy industry.

Lighter as flame control and temperature control in milk pasteurization system

Milk pasteurization involves heating milk at a specific temperature below its boiling point as a method to keep the resulting dairy product retaining the shape and taste characteristics of fresh milk. In several experiments, the use of fuzzy control systems has been tested to regulate the temperature in the milk pasteurization process and to time the ignition of the stove flame. However, this fuzzy approach still causes the system to give an unstable response and irregular stove flame. In order to study milk pasteurization, the Low Temperature Long Time (LTLT) method is used which is implemented automatically through a PID control system. This method serves to maintain nutritional quality by keeping the pasteurization temperature at a setpoint of 62°C. This control involves the use of servo actuators and electric lighters that are automatically regulated with the help of flame sensors. The flame sensor detects the presence of flame and ensures that the flame remains lit throughout the pasteurization process. At the end of the process, the flame sensor plays a role in breaking the flame by setting a certain threshold. This sensor operates within 10 CM of the flame source and will produce an analog output with a maximum value of 4000 when the flame is lit. When the flame is extinguished, the analog output of the sensor will reach a value of 4095. Testing of the milk pasteurization automation system is given a value for each PID resulting from the value of Kp = 31.8, Ki = 115.6, Kd = 4.4 and obtained a rise time value of 0.39 minutes, 0.61%, settling min of 60.88, and settling max of 62.38.

Effect of cooking temperature on alkaline phosphatase in the production of raw-milk Pecorino cheese

Alkaline phosphatase (ALP) is a native raw-milk enzyme used in many countries as the standard assay for rapidly validating the milk pasteurization process. Due to the increased restrictions on the production or import of cheeses produced from unpasteurized milk, ALP activity (<10 mU/g) in cheese was measured as a simple and reliable method to check proper milk pasteurization in cheese for both safety inspection and trading controls. In Sicily, the artisanal cheesemaking of the Protected Denomination of Origin (PDO) semi-hard cheeses made with raw sheep's milk, includes the cooking of the curd, after the whey separation, in the wooden vat under hot Scotta-whey (≥80°C), for 3 to 4 h and finally is left to cool at ambient temperature. Thus, the temperatures adopted during cheesemaking may inactivate the ALP enzyme. To this purpose, the aim of this study was to demonstrate how different temperatures of Scotta-whey (T35, T60, T70, T80, T90, and T100) used during the second cooking of Pecorino cheeses after molding for 3 h, influence the ALP activity in fresh and 3-mo aged cheese, both at core and outside. The results highlight that the rate of reduction of ALP was greater with increasing temperature of the second cooking, in particular for T 80°C curd indicating that the use of Scotta-whey >80°C, could be a breakpoint able to reduce the ALP activity to <10 mU/g values. Different effects between the core and the outside portions of the experimental cheeses were found, with a decrease in ALP activity more on the outside than in the core portions, both in fresh and 3-mo aged cheeses, for T80, T90, and T100 treatments. Care must be taken in using the ALP to control the use of pasteurized milk in the production of PDO cheeses without considering the cheesemaking processes, such as the second cooking, which could be equal to pasteurization and an adequate interaction time/temperature can reduce the ALP activity to values comparable with cheeses produced with pasteurized milk.

Design considerations for developing geothermal-assisted milk pasteurization equipment

The naturally occurring heat inside the earth is renewable and sustainable and is known as geothermal energy. It is a renewable energy source that may be used in various applications, including milk pasteurization. This research focuses on the design considerations for developing geothermal-assisted milk pasteurization equipment which is first of its kind in Gujarat, India in direct application of geothermal energy. The novelty of this device is that it utilizes geothermal water (63 °C) from a self-flowing well to pasteurise milk. The utilization of direct heat energy from geothermal resource reduces the operational cost of milk pasteurization process. It discusses the various aspects of the design process, including efficiency calculation, heat exchange principles, system components, and control strategies. The study also discusses the result of the laboratory analysis of pasteurized milk considering microbiological and chemical parameters. The unit reduces the total plate count to 28,000 cfu/ml, within the recommended range for the WHO (30,000 cfu/ml). The paper concludes by discussing societal benefits and techno economic aspect of geothermal-assisted milk pasteurization equipment.

Ammonia-based compression heat pumps for simultaneous heating and cooling applications in milk pasteurization processes: Performance evaluation

Ammonia-based heat pumps were investigated to deliver heating (65–95 °C) and cooling (2 °C) simultaneously for the pasteurization of raw milk. Two compression heat pump configurations using a pure refrigerant (ammonia) and zeotropic mixture (ammonia/water) as working fluids were integrated with raw milk pasteurization process: two-stage ammonia compression heat pump with closed intercooler, and two-stage ammonia/water compression heat pump with a solution circuit. The integrated heat pump systems performance simulations were carried out at the base-case design conditions and parametric study on the influence of key operational variables on the system's first- and second-law efficiencies. These heat pumps are attractive and more efficient solutions than current heating and cooling systems used in the dairy processing industries (fossil-fuel-fired boiler and ammonia compression chiller) by up to 59% of a primary energy saving. Besides, the two-stage ammonia/water heat pump operates at a lower system high pressure than the ammonia heat pump, which allows reducing the cost of the system components, especially for the compressor. The development of such types of multi-stage compression heat pumps (with large-temperature-lift) using zeotropic mixture with wide temperature glide, as a working fluid, significantly contributes towards the decarbonization of the dairy processing industry.

Performance Analysis of the Milk Pasteurization Process Using a Flat Plate Solar Collector

A large share of Ethiopia’s milk production comes from its rural areas. However, this milk does not undergo further processing into dairy products on a large scale due to lack of conventional energy sources such as electricity and gas. Hence, the country is not utilizing its milk resources to the maximum possible. In this study, the possible use of solar energy for the milk pasteurization process is investigated by using a flat plate solar collector (FPSC) with and without reflectors integrated. Reflectors added to the FPSC have augmented the incident solar radiation on the collector from 0.27–0.91 kW/m2 to 0.36–1.18 kW/m2. The thermal efficiency obtained for the FPSC with reflectors integrated is 51.8% whereas that of the collector without reflectors integrated is 46.2%. Likewise, the exergy efficiency is found to be 5.43% for the collector integrated with reflectors and 2.53% for the collector without reflectors. Also, an increase in the daily processed milk production of 18% is observed in September and 16% in November by using the solar collector with reflectors integrated. The quality of pasteurized milk is checked by using the methylene blue reduction test (MBRT) method, and it indicates a better quality of pasteurized milk when compared with raw milk. Therefore, this study shows that the use of solar energy for milk pasteurization has great potential to increase the shelf life of milk, and it can be used as an instrument to improve the quality of life of people living in rural areas.

Thermal Energy Consumption Assessment in a Fluid Milk Plant

The main energy conservation opportunities in a dairy plant are in refrigeration, and steam generation. This paper aims to identify potential energy and water savings and opportunities to improve the thermal efficiency of a fluid milk processing plant, using energy analysis and Heat Integration methods. Methodologies for energy analysis and Pinch Analysis with the use of HENSAD and Aspen Energy Analyzer are applied. The main specific energy consumptions are defined as indicators of the progress of improved energy efficiency. The determination of energy performance indicators and energy targets of the heat exchanger network, as well as its design, allowed identifying opportunities for improvement to reduce fuel and water consumption through heat recovery in the milk pasteurization process. Current hot and cold utilities duties are satisfied, for a minimum allowable temperature difference of 20 °C. Total annual savings of 60 t of fuel oil and 15,800 m3 of water allow assessing the feasibility of an investment project for improved heat recovery.

IMPROVEMENT OF BRUSH CHEESE RECIPES BRYNZA TYPE WITH HIGH TITER OF LACTIC BACTERIA

Fermented milk products made by fermenting milk with lactic acid bacteria play an important role in children's nutrition. In particular, brine cheese type "Brynza" has other advantages, including efficient use of raw materials, the ability to sell cheese without maturation or with a short maturation period (not more than 14 days), rapid return on investment. Optimization of the recipe and selection of raw materials for the production of young pickled cheeses with high titers of lactic acid bacteria is an urgent task today in the development of medium-sized businesses and craft industries in Ukraine. It was found that the increase in acidity of the product is influenced by the addition of different composition of starter cultures (Lactococcus lactis subsp. Lactis; Lactococcus lactis subsp. Cremoris; Lactococcus lactis subsp. Lactis (bio diacetylactis); Leuconostoc mesenteroides subsp. effects on acid shift. It was found that organoleptic parameters do not significantly depend on the use of milk pasteurization process, so the use of an additional stage of milk preparation will contribute not only to the profitability of the recipe and raw materials, but also to potential demand for brine cheese "Brynza". It was found that the largest number of living cells of lactic acid bacteria is characteristic of cheese samples made with additional inoculation of starter cultures. Recommendations are given for the use of recipes and the choice of raw materials for the production of brine cheese type "Brynza" with a high titer of lactic acid bacteria.

Application of a novel heat pump model for estimating economic viability and barriers of heat pumps in dairy applications in the United States

Heat pumps represent an important opportunity for energy savings and decarbonization. This work investigates the techno-economic performance of high-temperature heat pumps (HTHPs) for use in the U.S. dairy industry. The studied heat pump performs a 50 °C temperature lift on a waste heat stream of cleaning water and applies the upgraded heat stream to a fluid milk pasteurization process. This work involved the creation of a HTHP model that estimated the coefficient of performance (COP), internal rate of return (IRR), net present value (NPV), and payback period (PBP), and emissions saved for a heat pump replacing a natural gas boiler. Capital costs, operations, and maintenance (O&M) cost, heat pump lifetime, electricity prices, natural gas prices, and a cost of carbon were varied to perform a parametric study on the factors affecting the break-even price of HTHPs. The results show that HTHP economics are highly sensitive to COP and energy price environment, and less sensitive to capital and O&M cost variance, leading to a large scatter of positive and negative NPVs based on U.S. location. PBPs demonstrate a defined threshold, based on energy price environment, below which favorable two-to-three-year PBPs predominate. This work is focused on the U.S. dairy industry, but international application in relation to fossil vs. electricity price regimes. Heat pumps have seen wider adoption in regions with a high ratio of fossil energy to electricity prices ($/MMBTU vs. $/kWh). The U.S. has plentiful natural gas resulting in lower fossil energy prices which has reduced heat pump adoption. This paper identifies potential first mover industries for HTHP adoption and their associated price regimes even in regions with lower ratios of fossil energy to electricity prices that exist many places globally.

SUPERVISED TUNING OF A CHILLER WITH A COLD PHASE-CHANGE MATERIAL USING AN RSM-SMITH PREDICTOR

The proposed work is focused on the tuning of the latent-heat storage of a PCM with MWCNT encapsulation for a chiller system in the milk-pasteurization process using an RSM-based predictive Smith controller. The PCM was synthesized using sodium polyacrylate and MWCNT particles, encapsulated in spherical balls stored in the IBT (ice bank tank of the chiller unit). Experimental work is conducted on the heat-transfer characteristics of the chiller unit with servo-operated flow-control valves based on the central composite design of experiments. The system is cascaded using a PID controller with a Smith predictor to stabilize the latent temperature of milk cooling in the chiller system. The system is considered to be a first-order transformation with the rise and settling time. The plant model is obtained, using the response-surface method based on the transfer function to minimize the error derivatives of the chiller system. Results of the proposed method show a robust performance in keeping the PCM temperatures and bacterial-growth value stabilized, allowing a less drastic control compared to the cascade-model predictive control.

Control of high temperature short time milk pasteurization plant with centralized and decentralized linear quadratic regulators

ABSTRACT Precise temperature control in each stage of the pasteurization process is important to deactivate pathogenic bacteria, and any temperature fluctuations during milk processing may affect the nutritional value and quality of the milk. Hence, maintaining stable temperature and minimizing disturbance effects is essential for improved quality of the milk. This necessitates an efficient controller that may provide precise temperature control despite process disturbances. Here, a mathematical model representing the high-temperature short-time (H.T.S.T) milk pasteurization process is simulated. The proposed model is simulated without a pre-cooling stage, thereby contributing to energy minimization but without compromising the operating conditions of the process. The design of a Linear Quadratic Regulator (L.Q.R)-based centralized and decentralized control for the H.T.S.T milk pasteurization process is implemented. The L.Q.R exhibits good results at disturbance rejection and targets mainly the objective function minimization. So, minimizing the energy is the prime objective of the L.Q.R. The centralized and decentralized L.Q.R structures were designed for the proposed plant, and the control scheme efficiencies are analyzed. The juxtaposition of these two control schemes reveals that the decentralized L.Q.R structure outperforms the centralized structure for the H.T.S.T milk pasteurization process.

Performance Analysis of Plate Heat Exchanger with Nanofluid using Milk Pasteurization

Experimentally to analyzed the enhance performance of Plate heat exchanger in milk pasteurization process using nanofluid at different concentration of 0.1%,0.15%,0.2% 0.25% and 0.3%. in this work the nanoparticles like Al2O3 and the base fluid like dematerialized water is used to prepare nanofluid by using two steps method. Exchanger is one of the thermal energy transferring devices, which transfer the heat between different fluids. This is widely used in different application because of its compact in size and higher efficiency compared to other type of heat exchanger. The main focus of using nanofluid is that it has improvement in thermal conductivity. Then the hot fluid as milk and cold fluid as nanofluids are used. The heat transfer rate is increased with increasing the concentration of nanofluid. It conducted by varying operating parameters like mass flow rate of hot milk, mass flow rate of nanofluid, inlet and outlet temperatures of hot milk and inlet outlet temperature of nanofluid. The main objective of this work is to find out mass flow rate and overall, all heat transfer coefficient.

Reflective Array Solar Water Heater for Milk Pasteurization

The solar water heater is a method of utilizing solar thermal energy by storing heat energy in water which can be used directly. Solar thermal energy has a high utility potential. It has a power of 1 kW/m2 on average on the surface of the earth with energy up to 7 kWh/m2/day on average per year. One of the uses of the solar water heater is that it can be implemented in the milk pasteurization system. The research equipment consists of an accumulator vessel with an area of 2x2 m2 and a water pipe collector. The water that had been heated in an accumulator (thermos) was used directly as the heating source in the milk pasteurization process. Meanwhile, the most common heating method used in the pasteurization process is electricity and gas energy. The result showed that using 82oC of accumulator water, it took 12 minutes (14.48–15.00) to reach the milk temperature needed in the pasteurization process which is 70oC for 6.75 litres of milk. The efficiency of solar heat energy absorption by an accumulator is 47%. This value can be increased by increasing the volume of water.

Novel compound waste heat-solar driven ejector-compression heat pump for simultaneous cooling and heating using environmentally friendly refrigerants

This work investigates the theoretical performance of a novel compound waste heat-solar driven ejector-solar assisted heat pump for simultaneous heating and cooling purposes. The system utilizes waste heat from three different sources, PV/T (photovoltaic thermal) with flat plate collector, milk pasteurization process, and condenser exchange heat. Real weather data is employed to determine the hourly performance of the system in three European cities, Valencia (Spain), Berlin (Germany), and Stockholm (Sweden) representing warm, middle and cold climates, respectively. Moreover, R450A and R513A alternative refrigerants are compared to the greenhouse gas R134a. The results show that the proposed system improves cooling COP by 7% using R450A in comparison with a conventional R134a vapor compression system. Furthermore, the utilization of waste heat recovery enhances the system COP from 3.7 to 4 in the absence of solar intensity. On the other hand, the results of the heating mode show that the system with PV/T and using R450A has a COP increase over the adopted solar time, ranging from 2 to 5% in Valencia; 2 to 2.5% in Berlin, and1 to 1.5% in Stockholm. However, R513A shows a COP reduction of about 5% in comparison to R134a. Regarding the heating mode with waste heat utilization from milk pasteurization, the system based on R450A results in the highest system COP, increasing COP up to 75% compared to the R134a baseline scenario. Overall, the proposed R450A systems show the highest equivalent carbon dioxide emission reduction and, therefore, it is recommended from an environmental point of view.

DEVELOPMENT AND PERFORMANCE EVALUATION OF MILK PASTEURIZATION UNIT

The main objective of the present investigation was to use the modern technological modifications for the milk pasteurization process. The original milk pasteurization unit was developed especially for the present work by adding a pneumatic regulating valve to improve its performance. The performance of the milk pasteurization unit before and after development was experimentally studied under four different heating temperatures (70, 74, 77 and 80oC), four different vapor pressures (200, 400, 600 and 800 kPa) and four different cooling temperatures (3, 4, 5 and 6oC). Evaluation of the milk pasteurization unit was carried out taking into consideration pasteurization unit productivity, heating rate, fuel consumption, energy requirements, bacteria count and final product quality. The experimental results revealed that pasteurization unit productivity (258 kg/hr.), heating rate (4.9oC/s) fuel consumption (144 l/hr.), energy requirements (1.74 kW.hr./kg ) and bacteria count (35), were in the optimum region under conditions of using the developed milk pasteurization unit at 74oC heating temperature, 400 kPa vapor pressure and 4oC cooling temperature.

Adaptive Feedback Control for a Pasteurization Process

The milk pasteurization process is nonlinear in nature, and for this reason, the application of linear control algorithms does not guarantee the obtainment of the required performance in every condition. The problem is here addressed by proposing an adaptive algorithm, which was obtained by starting from an observer-based control approach. The main result is the obtainment of a simple PI-like controller structure, where the control parameters depend on the state of the system and are adapted online. The proposed algorithm was designed and applied on a simulated process, where the temperature dependence of the milk’s physical properties was considered. The control strategy was tested by simulating different situations, particularly when time-varying disturbances entered the system. The use of the adaptive rule reduces the variance generally introduced by the PI or PID controller.

Identification of high temperature short time milk pasteurization unit

AbstractThis research pertains to the development of a dynamic‐model and identification of parameters for high‐temperature‐short‐time (HTST) pasteurization process using plate‐heat‐exchangers for precise controller scheme for this process. Real‐time HTST process consists of three integrated sections, (a) plate‐heat‐exchanger engaged in regeneration, heating and cooling (b) holding tank, and (c) holding tube. The models for these sections are identified using Matlab. The dynamics of the HTST process using the first‐principle method consisting of two inputs one‐output model is derived. The parameters of the dynamic model are identified using the autoregressive‐exogenous linear identification technique, ARMAX, and subspace system identification to predict the outlet temperature of HTST process. Finally, a dynamic‐model, relating exit temperature to input enthalpy is obtained from the closed‐loop process input–output data, using a nonlinear least‐square‐estimation technique. The quality of prediction of linear‐model structures is checked using plant's data. The results obtained from the linear‐models are in good agreement with plant‐data.Practical applicationMilk should be free from toxins and pathogens and also it must retain all nutrients and vitamins with extended period of storage life. To achieve the above said criteria, milk is heated to a particular temperature for a brief time then cooling it down once more quickly. Moreover, to avoid superheating, the temperature needs to be controlled. As model‐based‐control perform satisfactorily, tuning of controllers can be done using model parameters of this milk‐heating process. These model parameters are obtained from on‐line identification of the predicted model using real time plant input–output data. This paper deals with identification of model parameters for the milk pasteurization process. The formulated model equations are also validated, which will help in optimizing the operating parameters and scale‐up design.

Zoonosis: Origin and Control of Zoonotic Diseases: A Mini Review

ABSTRACT: Evolving infectious diseases have been a reason for significant worldwide threats to health of human beings. In most cases, humans are unintentionalhosts of an infectious cycle sustained by animal hosts, comprising insects as well. The rise of new contagious ailments such as severe acute respiratory syndrome (SARS), pandemic influenza and HIV/AIDS has revealed the susceptibility of humans to novel zoonotic health emerging intimidations. These infections are initiated by many different pathogenic agents. According to an estimate about 50 % of the approximately 1000 species of pathogens that are prominent in livestock and pets are zoonotic in nature. In past 60 years, many developed countries have effectively controlled zoonotic diseases through expensive public investments, easing synchronized involvements, comprising ''test and slaughter,'' feed prohibitions, massive vaccination of livestock and wildlife, education, health, and milk pasteurization processes. These are extremely effective approaches of eradicating zoonotic diseases which necessitate important, effective,legal, and economic insurances. Main purpose of this mini review article is to highlight the origin and control of pandemic zoonotic diseases which are the demand of time and need of the present era.

Optimization of Design Heat Exchanger to Reduce Fouling Resistance in Milk Pasteurization

Milk pasteurization process used Heat Exchanger (HE) to heat fresh milk at certain temperature and time period. Fouling in heat exchanger during milk pasteurization has been identified as a major problem in the efficiency of energy. Due to insufficient temperature during process, foodborne pathogens may not be killed properly and contaminate the food which make the human health adverse. Other problems may arise in fouling which is losing the efficiency during operation, increasing cost of pumping and downtime that affecting the efficiency of production cost. The fouling resistance depends on milk properties, heat exchanger design technologies and actual operating conditions. The objective of this research was to optimize the heat exchanger design of milk pasteurization by considering series-parallel connection to minimize fouling. The research method was using recent stochastic algorithms Duelist Algorithm, Killer-Whale Algorithm and Rain-Water Algorithm for fouling mitigation in milk pasteurization. The optimization results show the series-series connection reduce fouling up to 16% at the tube side (Rft) and reduce up to 5% at shell side.