Assessment of the Thermal Treatment of Milk during Continuous Microwave and Conventional Heating

The effect of continuous-flow microwave treatment of milk was estimated by using indicators of the heat treatment intensity (β-lactoglobulin denaturation, inactivation of alkaline phosphatase and lactoperoxidase). Results were compared with those obtained using a conventional process having the same heating, holding, and cooling phases. Continuous microwave treatment proved to be an effective system for pasteurizing milk, with the inclusion of a holding phase to maintain the time and temperature conditions required. At high pasteurization temperatures, the extent of thermal denaturation observed with the microwave treatment was lower than that obtained with the conventional system. This result could be attributed to a better heat distribution and the lack of hot surfaces contacting the milk in the case of the microwave unit.

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Vitamin B1 and B6 Retention in Milk after Continuous-Flow Microwave and Conventional Heating at High Temperatures

Journal of Food Protection ◽

10.4315/0362-028x-64.6.890 ◽

2001 ◽

Vol 64 (6) ◽

pp. 890-894 ◽

Cited By ~ 9

Author(s):

ISABEL SIERRA ◽

CONCEPCIÓN VIDAL-VALVERDE

Keyword(s):

High Temperatures ◽

Continuous Flow ◽

Vitamin B6 ◽

Vitamin B1 ◽

Raw Milk ◽

Microwave Treatment ◽

Conventional Heating ◽

Conventional System ◽

Tubular Heat Exchanger ◽

Heating And Cooling

The effect of continuous-flow microwave treatment at high temperatures on the retention of vitamins B1 and B6 in raw milk with different fat content was evaluated. Results were compared with those obtained using a conventional system (tubular heat exchanger) with the same heating and cooling phases. Heat treatment of whole (3.4% fat) and skim (0.5% fat) milk at 90°C produced no losses of vitamin B1 or vitamin B6 (pyridoxamine and pyridoxal). However, at 110 and 120°C, while vitamin B1 content of milk remained constant, pyridoxamine increased (4 to 5% and 9 to 11%, respectively) and pyridoxal decreased (5 to 6% and 9 to 12%, respectively). Under the assayed conditions, no differences were observed between the content of these vitamins in conventionally and continuous-flow microwave-treated milk.

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The Effect of Heat Treatment on Chalcopyrite

Physical Separation in Science and Engineering ◽

10.1080/1478647031000101296 ◽

2003 ◽

Vol 12 (1) ◽

pp. 23-30 ◽

Cited By ~ 15

Author(s):

C. Sahyoun ◽

S. W. Kingman ◽

N. A. Rowson

Keyword(s):

Heat Treatment ◽

Magnetic Susceptibility ◽

Surface Effect ◽

Froth Flotation ◽

Xrd Analysis ◽

Microwave Treatment ◽

Phase Changes ◽

Conventional Heating ◽

Magnetic Fraction ◽

Conventional Heat Treatment

The influence of conventional heat treatment and microwave radiation on chalcopyrite was investigated. There was a significant increase in the proportion of material recovered to magnetic fraction and magnetic susceptibility with conventional heating time. XRD analysis detected phase changes in conventional heat-treated chalcopyrite, which increases the magnetic susceptibility of the ore and enables its effective magnetic separation, which is impossible to achieve in its original state.With microwave treatment, the magnetic susceptibility increases and the proportion of material recovered to magnetic fraction on the induced rolls is also increased. However, XRD analysis failed to detect any phase changes. A possible explanation for this observed behaviour is that the more magnetic component that has been formed by microwave treatment is below the threshold of detection of the XRD analyser. Taking into account that results from the froth flotation tests indicated that % weight fraction in the concentrate decreases with microwave exposure time, the change might be due to a surface effect.

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A calorimetric study of the thermal denaturation of whey proteins in simulated milk ultrafiltrate

Journal of Dairy Research ◽

10.1017/s002202990002046x ◽

1977 ◽

Vol 44 (3) ◽

pp. 509-520 ◽

Cited By ~ 182

Author(s):

M. Rüegg ◽

Ursula Moor ◽

B. Blanc

Keyword(s):

Heat Treatment ◽

Xanthine Oxidase ◽

Conformational Changes ◽

Thermal Denaturation ◽

Whey Proteins ◽

Calorimetric Study ◽

Thermal Transitions ◽

Scanning Calorimetry ◽

Β Lactoglobulin ◽

Dsc Thermograms

SummaryDifferential scanning calorimetry (DSC) was used to study thermal transitions of the following whey proteins and enzymes in milk ultrafiltrate solution: β-lactoglobulin, α-lactalbumin, serum albumin, γ-globulin, apo- and Fe-lactoferrin, lysozyme, ribonuclease, α-chymotrypsin and xanthine oxidase. Denaturation enthalpies (ΔHD), denaturation temperatures (TD) and the half width of the denaturation peaks in DSC thermograms (ΔT½D) were determined and the degree of renaturation was estimated by rescanning previously denatured samples. A fair correlation between the results obtained by DSC and other more classical methods was found in general. However, for some proteins (α-lactalbumin, lysozyme, ribonuclease and xanthine oxidase), which have so far been considered relatively thermostable, calorimetry reveals conformational changes starting at temperatures as low as about 45 °C. In these cases thermostability observed after heat treatment of milk should be interpreted in terms of renaturation and not of high temperatures of denaturation.

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The effects of continuous flow microwave treatment and conventional heating on the nutritional value of milk as shown by influence on vitamin B 1 retention

European Food Research and Technology ◽

10.1007/s002170050508 ◽

1999 ◽

Vol 209 (5) ◽

pp. 352-354 ◽

Cited By ~ 12

Author(s):

Isabel Sierra ◽

Concepción Vidal-Valverde ◽

Agustín Olano

Keyword(s):

Continuous Flow ◽

Nutritional Value ◽

Microwave Treatment ◽

Conventional Heating ◽

Vitamin B

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Reaction kinetic pathway of reversible and irreversible thermal denaturation of β-lactoglobulin

Dairy Science & Technology ◽

10.1051/lait:2007012 ◽

2007 ◽

Vol 87 (4-5) ◽

pp. 301-315 ◽

Cited By ~ 97

Author(s):

Alexander Tolkach ◽

Ulrich Kulozik

Keyword(s):

Thermal Denaturation ◽

Reaction Kinetic ◽

Β Lactoglobulin

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Dried milk. Assessment of heat treatment intensity. Method using high-performance liquid chromatography

10.3403/02713573u ◽

2015 ◽

Keyword(s):

Heat Treatment ◽

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

High Performance ◽

Treatment Intensity

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Microwave-Assisted Grafting to MCM-41 Silica and its Application as Catalyst in Flow Chemistry

Australian Journal of Chemistry ◽

10.1071/ch11125 ◽

2011 ◽

Vol 64 (11) ◽

pp. 1522 ◽

Cited By ~ 13

Author(s):

Manuela Oliverio ◽

Antonio Procopio ◽

Toma N. Glasnov ◽

Walter Goessler ◽

C. Oliver Kappe

Keyword(s):

Continuous Flow ◽

Rate Increase ◽

Flow Chemistry ◽

Conventional Heating ◽

Kinetic Effect ◽

Microwave Technology ◽

Microwave Assisted ◽

Technology Control ◽

First Time ◽

Mcm 41

Finding environmentally gentle methods to graft Lewis acid on the surface of mesoporous materials is a topic of current interest. Herein we describe the optimization of a preparation procedure of a mesoporous silica-supported ErIII catalyst using the microwave-assisted post-calcination functionalization of Mobil Composition of Matter-41 silica as the key step. The required time for functionalization was reduced from several hours to 10 min using sealed-vessel microwave technology. Control experiments using conventional heating at the same temperature demonstrated that the rate increase is owing to a simple thermal/kinetic effect as a result of the higher reaction temperature. The resulting ErIII catalyst was tested for the first time as a catalyst in the continuous flow deprotection of benzaldehyde dimethylacetal and a complete leaching study was performed.

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