Cooling Temperature Research Articles

Effects of the Cooling Temperature at the Farm on Milk Maturation and Cheesemaking Process in the Manufacture of Parmigiano Reggiano PDO Cheese.

Simple SummaryCurrently, the official protocol of Parmigiano Reggiano, a hard, cooked Italian PDO cheese, prohibits cooling the milk at the farm below 18 °C. As Parmigiano is made from raw milk, the microbiological characteristics of the raw matter have a strong impact both on the cheesemaking process and cheese quality. A lower cooling temperature, i.e., 9 °C, could better keep under control the microbial growth rate, which affects both the total bacterial count and specific species that are detrimental for dairy products. In this research, the impact of keeping milk at the farm at 9 °C on milk quality and cheese characteristics was investigated. The outcomes of the study showed that while the microbiological aspects benefited from the lower temperature, the coagulation properties of milk tended to worsen and caused slightly higher losses of macroconstituents in the whey. Nevertheless, the cheesemaking process and cheese features were not substantially modified, suggesting that the improvement of the microbiological aspects largely offsets the worsening of coagulation properties. The results of this research represent a scientific contribution to get to a formal request for modification of the Parmigiano Reggiano regulation, which, once accepted, could improve the hygienic characteristics of milk and, possibly, the final quality of Parmigiano Reggiano cheese.Parmigiano Reggiano is a hard PDO cheese made from bovine raw milk, whose microbiological characteristics have important repercussions on cheese quality. According to the EU official production protocol, milk temperature at the farm must not drop below 18 °C. The present research aimed to study the effect of cooling milk at the farm at 9 °C on the characteristics of milk and on the cheesemaking process and losses during manufacture. Six cheesemaking trials were performed in two different dairies. In each of them, two cheesemakings were made in parallel: one with milk kept at 9 °C (TM9) and the other with milk kept at 20 °C (TM20). TM9 milk, in comparison with TM20, showed after the creaming process a significant reduction not only of total bacterial count but also of psychrotrophic and lipolytic bacteria. At the same time, TM9 milk showed a higher creaming capacity and, consequently, a lower fat content than TM20. TM9 vat milk had worst coagulation properties than TM20, which caused slightly higher loss of fat and curd fines into the whey. Nevertheless, these changes were too small to influence the efficiency of the cheesemaking process; conversely, maintaining milk at the farm at 9 °C led to a reduction of the number of spoilage bacteria.

Optimization of Modelling of storage conditions in forced Air cooling of SAPOTA (MANILKARAZAPOTA) using Response Surface Methodology

Field heat can cause rapid deterioration of horticultural crops and therefore it is desirable to remove this heat as quickly as possible after harvesting, and the faster the deteriorative processes are retarded. Thegoal of the present study was to apply Response surface methodology (RSM) to search for the best conditions of Forced Air-Cooling system for extending the shelf life of Sapota.The parameters which affect the cooling rate the most were identified as Cooling Medium temperature (4 ̊C, 8 ̊C and 25 ̊C), Fruit Size (0.00454 m, 0.00567m and 0.00662 m) andCooling Air Velocity (0.5 m/s, 1.5 m/s and 2.5 m/s) at which the produce is stored. Based on general factorial design of RSM shelf life (number of days) as a response, 27 (33) treatments were conducted.Optimum storage conditions for maximizing the shelf life wereidentified as Cooling Medium temperature (4 ̊C), Fruit Size (40-50 mm) and Cooling Air Velocity (2.5 m/s). Under this optimum condition, the predicted shelf life of the stored Sapota and the experimental results gave close values of less than 1.03 %. The number of days of shelf life extended for Sapota is 28days. Physio-chemical properties and microbial quality of stored Sapota was also evaluated. Percentage Loss in Weight was found to be maximum for control sample (13 %) whereas minimum for the cooled sample (0.04-0.123%). TSSincreased about 5%-7% for controlbut whereas for cooled sapota it was not more than 1-2%.

The Influence of Indirect Air-Cooling Combined with Evaporative Cooling on Tomato Fruit Cooling Time and Temperature

This study developed a low cost and affordable to small-scale farmers’ indirect air-cooling combined with evaporative cooling (IAC+EC) system for storage of fruit and vegetables under both arid and hot; and humid and hot climatic conditions. Field heat from freshly harvested produce should be immediately removed through cooling to the desired storage temperature. The aim of this study was to determine the effectiveness of IAC+EC system in terms of the cooling time requirement of the fresh tomato fruit. A fresh tomato cooling experiment to remove field heat during the summer month of September in Pietermaritzburg was conducted for 36 hours where the IAC+EC system was compared to storage under ambient conditions. The results showed that 16 hours was required to reduce the flesh temperature of tomatoes to 16.5oC while the flesh temperature for tomatoes under ambient conditions followed the ambient temperature profile with time of storage. The IAC+EC system reduced and maintained the microenvironment air temperature inside the coolers to 16.50C- 19°C. The ambient temperature varied between 21 and 32°C. The results in this study are evidence that IAC+ EC system can be a choice to farmers, for cooling the fresh by reducing the field temperature after harvest.

Effect of The Cooling Temperature on the Performance Of A Solar Adsorption Chiller with the Enhanced Mass Transfer

Effect of The Cooling Temperature on the Performance Of A Solar Adsorption Chiller with the Enhanced Mass Transfer

Effect of Initial Cooling Temperature on Structural Behaviors of Gelled Waxy Crude Oil and Microscopic Mechanism Investigation

A comprehensive investigation of the effect of initial cooling temperature on the structural behaviors of gelled waxy crude oil is conducted, including the “temperature-dependent viscoelasticity be...

Effects of Final Cooling Temperature on Microstructure Transformation and Properties of Q550 Low Carbon Bainite Steel

The mechanical properties of low carbon bainite steel are closely related to the microstructure and proportion after phase transformation. The microstructure of the deformed austenite of low carbon bainite steel after isothermal transformation and continuous cooling transformation was studied by thermal simulation test. The metallographic structure was observed by optical microscopy (OM) and scanning electron microscopy (SEM). The metallographic and microhardness were used to judge the microstructure type, and the CCT (continuous cooling transformation) curve and TTT (time-temperature-transformation) curve of the test steel were drawn. It was found that at 700-430 °C isothermal, undergo a variety of medium-temperature microstructure transformations appeared for the test steels, such as ferrite, pearlite, granular bainite and lath bainite. The cooling rate and final cooling temperature have great influence on the type and performance of the final microstructure. The final cooling temperature was controlled at about 515°C. The mixed microstructures of granular bainite (GB) and fine martensite-austenite (M-A) island, a small amount of acicular ferrite and lath bainite were obtained. The yield and tensile strengths of this type of microstructure reached 639 MPa and 750 MPa respectively, the shrinkage rate reached 17%, and the better low-temperature impact performance was realized.

여름철 작업자들의 고체온증 예방을 위한 액체냉각복 개발 및 효과적인 냉각온도와 인체 냉각부위 탐색

여름철 작업자들의 고체온증 예방을 위한 액체냉각복 개발 및 효과적인 냉각온도와 인체 냉각부위 탐색

Safety of Lower Scalp Cooling Temperature to Prevent Hair Loss From Chemotherapy in Breast Cancer Patients

Safety of Lower Scalp Cooling Temperature to Prevent Hair Loss From Chemotherapy in Breast Cancer Patients

Numerical Investigation of the Cooling Temperature of the InGaP/InGaAs/Ge Subcells Under the Concentrated Illumination

AbstractThe multijunction solar cells performances study is essential for the design of the high-concentration photovoltaic. These cells can operate over a wide range of the incident radiation flux and a large temperature range. These two parameters (concentration and temperature) degrade the cell and require a cooling system. In this article, we have studied numerically the cooling temperature of InGaP/lnGaAs/Ge subcells under the concentrated illumination. For this, we have presented the performance of each subcell as a function of the temperature and concentration sunlight. The different high concentrations ratios (1, 10, 100, and 1000 sun) have been conducted according to the dish-style concentration photovoltaic system for three temperature valuesT= 300, 500, and 800 K. The results show that under high concentrated light intensity conversion, the performances of these three subcells (efficiency, open-circuit voltage, short-circuit current, and fill factor) were decreased with increasing the temperature. The main objective of this study is to find the limit temperature of each subcell in order to introduce the cooling system. Thus, we can avoid the degradation of the tandem solar cell under the concentrated illumination.

Significance of Finish Cooling Temperature to Microstructure and Property Relationship of Low-Carbon V-N-Cr Microalloyed High-Strength Steel

Herein, three final cooling temperatures were employed to achieve high strength and toughness communication in the V-N-Cr microalloyed steels. This study shows that V-N-Cr microalloyed steel primarily consisted of ferrite, granular bainite, acicular ferrite, and a small quantity of M/A phase at the final cooling temperature of 600 °C, while the polygonal ferrite, lamellar bainite, granular bainite, and a small fraction of acicular ferrite were obtained at 450 °C. The width of lamellar bainite was ~ 200-400 nm, and acicular ferrite was composed of fine non-parallel ferrite platelet structures with high dislocations densities. As the final cooling temperature decreased further, the microstructure included granular bainite and lath bainite at 350 °C. The nanoscale precipitates of V-N-Cr microalloyed steel were divided into two types, large-scale precipitates near the grain boundary that precipitated at high temperatures and small precipitates of diameter 5-10 nm at low temperatures, which significantly contributed toward strength. The hot rolled low-carbon V-N-Cr microalloy steel exhibited optimal mechanical properties at the final rolling temperature of 830 °C, as well the final cooling temperature was 450 °C. The highest yield strength and tensile strength of V-N-Cr microalloyed steel were 835 MPa and 989 MPa, respectively. The outstanding impact toughness of 161 J tested at − 60 °C was received. The transformation strengthening and precipitation hardening played a crucial role in affecting the thermo-mechanical properties.

Analysis of Air Cooling (AC) System Auditorium Venue Third Floor Main Building of Politeknik Negeri Lhokseumawe

The aims of this study are to calculate the cooling load system on the auditorium space of Politeknik Negeri Lhokseumawe (PNL). This calculation is expected to contribute the energy savings is the system of air (STU). This study is conducting on the third floor of PNL, at the Auditorium venue. The cooling load system by using Cooling load temperature difference (CLTD) system based on ASHRAE Handbook Fundamental, 1993. The calculation of cooling load based on secondary date, and then the result was compared to cooling load installed capacities. The result of the research found that the maximum cooler burden at culminate condition is equal to 116957 Btu/hr (9,74 ton of refrigerant), While the installed refrigeration capacities is 61080 Btu/hr (5,09 ton of refrigerant), here fond a lacking (decreasing) of refrigeration burden equal to 55857 Btu/hr (4,65ton of refrigerant}. If the installed burden (load) as according to re-calculation result, hence thrift gap still can be obtained equal to 14%, by paring down the illumination of light; altering set temperature pint in room; minimizing SC (Shading of coefficient); and lessen of infiltrate external air.

Simultaneous Control of Crystal Habit and Particle Size of Ecabet Sodium Hydrate with Rapid Cooling Crystallization and Temperature Cycling

Simultaneous Control of Crystal Habit and Particle Size of Ecabet Sodium Hydrate with Rapid Cooling Crystallization and Temperature Cycling

Influence of Rapid Cooling Rate and Homogenization Temperature on the Ferrite Content and Microstructures of CD3MWCuN Castings

The influence of homogenization temperature and rapid cooling rate on the ferrite content and microstructures of CD3MWCuN was investigated using BSE-SEM images. For these experiments CD3MWCuN was homogenized at six different temperatures 1000 °C, 1050 °C, 1100 °C, 1150 °C, 1205 °C, and 1250 °C for 4 hours followed by air-cooling and water quenching. In addition to these samples two temperatures, namely 1150 °C and 1205 °C, were chosen and samples were cooled at the varying rates of 500 °C/h, 750°C/h, 850 °C/h, and 1000 °C/h. Determination of the resulting ferrite/austenite ratio revealed that homogenization temperature plays the dominant role in determining the final ferrite content. Slower cooling rates drop the amount of ferrite in a linear manner that is approximately constant for the different homogenization temperatures studied. An equation is proposed to predict the ferrite content covering the homogenization temperatures from 1000 °C to 1250 °C given that the initial ferrite amount present at the homogenization T is known.

Effect of Final Cooling Temperature on Microstructure and Mechanical Properties of a Cr-Ni-Mo-V Bainite Steel

The microstructural evolution and mechanical properties of a low-carbon high-strength bainitic steel under different final cooling temperatures were studied. The microstructures of the experimental steel at different final cooling temperatures were composed of acicular ferrite and granular bainite. A decrease in final cooling temperature resulted in an increase in volume fraction of granular bainite and a decrease in volume fraction of acicular ferrite. The specimen with the lowest final cooling temperature (459 °C) exhibited the highest yield strength, tensile strength, and yield ratio, and a lower total elongation than the specimens with the highest final cooling temperatures (501 and 535 °C) because of the higher volume fraction of granular bainite and finer bainitic ferrite lath. The specimen with the lowest final cooling temperature had a lower absorbed energy than that of the highest final cooling temperature, because the strip-like martensite–austenite (M-A) constituents that existed between the bainitic ferrite or in prior austenite grain boundaries reduced its toughness. At an intermediate final cooling temperature of 501 °C, the experimental steel exhibited excellent mechanical properties with a yield strength, tensile strength, and absorbed energy of 825 MPa, 1232 MPa, and 102 J, respectively.

Effects of Start and Finish Cooling Temperatures on the Yield Strength and Uniform Elongation of Strain-Based API X100 Pipeline Steels

Three types of strain-based API X100 pipeline steels composed of polygonal ferrite (PF), acicular ferrite (AF), granular bainite (GB), bainitic ferrite (BF), and martensite–austenite (MA) were fabricated by varying the start cooling temperature (SCT) and finish cooling temperature (FCT). The effect of the microstructure on the yield strength and uniform elongation before and after strain aging was investigated. In the H-H steel fabricated at a high SCT and low FCT, the reduction in uniform elongation after prestraining was small, but the uniform elongation after heat treatment increased because of the presence of many mobile dislocations around AF and GB, which are present in a relatively high fraction. Because the H-L steel fabricated at high SCT and low FCT has a considerable amount of BF as a result of the significant degree of supercooling, carbon atoms were readily trapped at dislocations inside the BF during heat treatment, which reduced the resistance to strain aging. On the other hand, the L-L steel had a large amount of soft PF transformed in the two-phase (austenite + ferrite) region and high fractions of AF and MA because it was fabricated at low SCT and low FCT. As a result, the uniform elongation of the L-L steel was slightly increased after heat treatment because mobile dislocations were readily generated around the PF and MA boundaries under deformation.

Neutron poison distribution in the central reflector to reduce the DLOFC temperature of a Th-LEU fueled OTTO PBMR DPP-400 core

ABSTRACTIn a previous study using a mixture of thorium and 20 a/o% LEU at 16 gram per fuel sphere heavy metal loading and adjusting the effective fuel enrichment to produce the same amount of cumulative energy per fuel sphere as with the 10 a/o% Low Enriched Uranium (LEU), the maximum Depressurized Loss Of Forced Cooling (DLOFC) temperature was reduced from 2273 to 1925 °C and 1811 °C for a symmetric and asymmetric core, respectively using an once-through-then-out (OTTO) fuelling scheme. This article presents an additional strategy for reducing the maximum DLOFC temperature by placing an optimized distribution of neutron poisons in the central reflector. This strategy produced maximum DLOFC temperatures of 1509 and 1448 °C for the symmetric and the asymmetric cores, respectively. These results are impressive as it means that the less complicated OTTO cycle with its lower capital cost achieved the same cumulative energy produced per fuel sphere than the standard six-pass refuelling scheme and that at substantially lower maximum DLOFC temperatures. Both the addition of the neutron poisons to the central reflector and the creation of a radially asymmetric core resulted in lower burn-ups that had to be reversed by increasing the enrichment of the fuel.

Effects of cooling temperatures and low pH on membrane properties and voltage-dependent currents of rat nociceptive-like trigeminal ganglion neurons.

Cooling temperatures and low pH have profound effects on somatosensory functions including nociception. The effects not only can be mediated by cooling temperature transducers and proton transducers expressed in subpopulations of somatosensory neurons but may also be mediated by ion channels involving membrane excitability such as voltage-dependent K+ channels in somatosensory neurons. In the present study, we performed the in situ patch-clamp recordings from nociceptive-like trigeminal ganglion neurons in ex vivo trigeminal ganglion preparations of adult rats. We determined effects of cooling temperatures and low pH on membrane properties and voltage-dependent currents in nociceptive-like trigeminal ganglion neurons. Action potential rheobase levels were decreased when nociceptive trigeminal ganglion neurons were cooled from 24°C down to 12°C or when extracellular pH levels were reduced from 7.3 to 6. This indicates that the excitability of nociceptive-like trigeminal ganglion neurons was increased at the cooling temperatures and low pH. The decreases of action potential rheobase levels were accompanied by increases of trigeminal ganglion neuron input resistances at cooling temperatures and low pH, suggesting a possible involvement of background K+ channels. Cooling temperatures and low pH suppressed voltage-activated inward Na+ currents and also voltage-dependent outward K+ currents in nociceptive-like trigeminal ganglion neurons. Voltage-dependent outward K+ currents in nociceptive-like trigeminal ganglion neurons consist of inactivating A-type K+ currents and non-inactivating type K+ currents, and the former were more sensitive to cooling temperatures and low pH. Collectively, suppressing multiple types of K+ channels may be associated with the enhanced excitability of nociceptive trigeminal ganglion neurons by cooling temperatures and low pH.

Analysis of Cooling Effectiveness and Temperature Uniformity in a Battery Pack for Cylindrical Batteries

In this paper, techniques to improve cooling and temperature uniformity in a simple battery pack are examined. Four battery pack configurations are developed. In the first configuration, an inlet plenum is added to a simple battery pack. In the second configuration, jet inlets are incorporated along with the inlet plenum, and in the third configuration, multiple vortex generators are added in addition to the inlet plenum. Finally, in the fourth configuration, an inlet plenum, jet inlets, and multiple vortex generators are incorporated into the battery pack. The results conclude that by adding inlet plenum, multiple vortex generators, and jet inlets in the same configuration, significant improvements are observed. The results also show that the maximum temperature of the battery pack is reduced by ~5%, and the temperature difference between the maximum temperature and the minimum temperature exhibited by the battery pack is reduced by 21.5%. Moreover, there is a ~16% improvement in the temperature uniformity of a single cell.

Effect of Different Retailing Methods on Quality of Sweet Cherry after Forced-air Cooling and Low Temperature Transportation

Effect of Different Retailing Methods on Quality of Sweet Cherry after Forced-air Cooling and Low Temperature Transportation

Influence of the Cooling Temperature on the Mechanical Behavior of an Oxidized Self-Healing Ceramic Matrix Composite

Composites made of ceramic for both fibers and matrix are aimed at being used in aerospace applications, which means being submitted to mechanical stresses at high temperatures in oxidizing and corrosive environments for long durations. The oxidation/corrosion resistance of these materials is linked to their ability to self-heal by creating an oxide phase which can restrict the access of the oxygen into the bulk of the material. During thermomechanical cycles, the distribution of O2 inside the material as well as the distribution and the state of the liquid oxides will undergo some modifications. A specific test has been conceived and performed in order to evidence the influence of the viscosity of this oxide on the mechanical properties of the material. Results have shown that the stiffening which is observed seems to be proportional to the increase in the viscosity of the sealing oxide, in conjunction with the decrease in the temperature.