Potential Implication of the Freezing Point Depression by Enzymatic Hydrolysis of Lactose in Milk1

The. potential problem of detecting added water in lactose-hydrolyzed milk by cryoscopic examination was investigated. The extent to which hydrolysis of lactose corresponded with a given freezing point was calculated and tested experimentally. Cryoscopic measurements were related to the percent of lactose hydrolyzed in milk. Hydrolyzed milks readjusted to normal freezing points with added water were examined by lactometer and sensory evaluations. Although such milk adulterated with up to 25% added water could escape detection by either cryoscopic or sensory evaluations, the Quevenne lactometer could detect 10% added water.

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FREEZING POINT VALUES AND MILK SOLIDS-NOT-FAT CONTENT OF RETAIL MILK1

Journal of Milk and Food Technology ◽

10.4315/0022-2747-24.2.48 ◽

1961 ◽

Vol 24 (2) ◽

pp. 48-52 ◽

Cited By ~ 1

Author(s):

R. W. Henningson

Keyword(s):

Freezing Point ◽

Fat Content ◽

Freezing Point Depression ◽

Processing Plants ◽

Added Water ◽

Milk Solids ◽

Area Data

Observed freezing point and milk solids-not-fat values were determined for approximately 400 retail samples. Most of these samples were systematically collected at monthly intervals over a calendar year from designated processing plants. The average observed freezing point value found was −0.529°C. The average MSNF value found was 8.88%. No relationship was expected, or found, between the observed freezing point value and the MSNF value of milks. The MSNF value did not assist in explaining high freezing point values or in confirming the presence of added water. It did prevent suspicion which could not be easily confirmed. A minimum freezing point depression standard, based on area data and administered in a manner similar to a minimum butterfat standard, appears to be the most feasible way of utilizing the cryoscopic method for the determination of added water in milk.

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FREEZING POINTS OF ANTI-COAGULANT SALT SOLUTIONS

The Journal of General Physiology ◽

10.1085/jgp.18.4.485 ◽

1935 ◽

Vol 18 (4) ◽

pp. 485-490 ◽

Cited By ~ 5

Author(s):

David I. Hitchcock ◽

Ruth B. Dougan

Keyword(s):

Sodium Chloride ◽

Linear Function ◽

Sodium Citrate ◽

Freezing Point ◽

Biological Fluid ◽

Linear Equations ◽

Freezing Point Depression ◽

Salt Solutions ◽

Freezing Points ◽

Sodium Chloride Solutions

By a method involving equilibration of ice and solution, and analysis of the solution, freezing point depressions of solutions of sodium citrate, oxalate, and fluoride have been determined over the range Δ = 0.45 to 0.65°C. Determinations with sodium chloride solutions have confirmed the accuracy of the method. In each case the freezing point depression is given, within 0.002°C., as a linear function of the concentration. By the use of these linear equations it is possible to prepare a solution of any of these four salts isotonic with a given biological fluid of known freezing point, provided the latter falls within the range studied.

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Thermomechanical Formulation of Freezing Point Depression Behavior of Liquid on Solid Surface With Nanostructure

Volume 11: Heat Transfer and Thermal Engineering ◽

10.1115/imece2020-23759 ◽

2020 ◽

Author(s):

Y. Hanawa ◽

Y. Sasaki ◽

S. Uchida ◽

T. Funayoshi ◽

M. Otsuji ◽

...

Keyword(s):

Experimental Data ◽

Freezing Point ◽

Freezing Point Depression ◽

Liquid Molecule ◽

Nanoscale Structures ◽

Freezing Points ◽

Dsc Measurements ◽

Thermomechanical Method ◽

New Equation ◽

Solid Liquid Interface

Abstract In this study, we investigated the freezing point depression of liquids in nanostructures using a new thermomechanical method. First, we experimentally determined the freezing points of water, cyclohexane, and a certain organic material (Chem.A) in nanoscale structures using DSC measurements. Thereafter, we formulated a new equation by improving the Gibbs–Thomson equation, which is the conventional formula for representing the freezing point depression of a liquid in nanostructures. We introduced a new term in this new equation to represent the increase in the kinetic energy of the liquid molecule as a result of collision between the liquid molecules and nanostructure walls. Subsequently, we evaluated the solid–liquid interface free energy of sublimation materials by fitting the theoretical freezing point derived from the new equation to experimental data. In this study, we succeeded in reproducing the experimental data of freezing point depression using the proposed equation. In particular, the freezing points of cyclohexane and Chem.A in the nanostructure were better fitted by this new equation at 10 nm or more compared with the conventional equation. Our results show that the interaction between the wall of the nanostructure and liquid molecules affects freezing point depression.

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Assessing the Enzymatic Hydrolysis of Salmon Frame Proteins through Different By-Product/Water Ratios and pH Regimes

Foods ◽

10.3390/foods10123045 ◽

2021 ◽

Vol 10 (12) ◽

pp. 3045

Author(s):

Pedro Valencia ◽

Silvana Valdivia ◽

Suleivys Nuñez ◽

Reza Ovissipour ◽

Marlene Pinto ◽

...

Keyword(s):

Enzymatic Hydrolysis ◽

Control Systems ◽

Ph Control ◽

Operating Conditions ◽

Molecular Characteristics ◽

Degree Of Hydrolysis ◽

Added Water ◽

Hydrolysis Of ◽

By Products ◽

Water Ratio

The enzymatic hydrolysis of fish by-product proteins is traditionally carried out by mixing ground by-products with water. In addition, pH control is used to avoid pH drops. Higher costs are involved due to the use of pH control systems and the consequent energy cost in the drying stage. This work aimed to evaluate the effect of these conditions on the hydrolysis of salmon frame (SF) proteins, including the SF hydrolysis without added water. SF hydrolysis by subtilisin at 50, 75, and 100% SF under different pH regimes were evaluated by released α-amino (α-NH) groups, total nitrogen, degree of hydrolysis, and estimated peptide chain length (PCL) at 55 °C. The concentration of released α-NH groups was higher in the conditions with less added water. However, the nitrogen recovery decreased from 50 to 24% at 50 and 100% SF, respectively. Changing the SF/water ratio had a more significant effect than changing the pH regime. Estimated PCL changed from 5–7 to 7–9 at 50 and 100% SF, respectively. The operating conditions affected the hydrolysis performance and the molecular characteristics of the hydrolysate.

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Freezing Points of Raw and Pasteurized Milks

Journal of Milk and Food Technology ◽

10.4315/0022-2747-39.7.462 ◽

1976 ◽

Vol 39 (7) ◽

pp. 462-463 ◽

Cited By ~ 2

Author(s):

G. H. WATROUS ◽

S. E. BARNARD ◽

W. W. COLEMAN

Keyword(s):

Freezing Point ◽

Cow Milk ◽

Freezing Points ◽

Added Water ◽

Point Data

Over 2,000 samples of cow milk and 243 samples of processed milk were analyzed for freezing point. Data suggest the need for continuing surveillance of both raw and pasteurized milks. During the course of the study, the incidence of freezing points in processed milks suggestive of added water dropped markedly. It is suggested this may have been due to information gained during the study and consequent response.

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Freezing Points and Milk Adulteration

Journal of Food Protection ◽

10.4315/0362-028x-40.4.272 ◽

1977 ◽

Vol 40 (4) ◽

pp. 272-273 ◽

Cited By ~ 1

Author(s):

S. E. BARNARD

Keyword(s):

Freezing Point ◽

Food Technology ◽

Department Of Agriculture ◽

Freezing Points ◽

Milk Samples ◽

Milk Adulteration ◽

Added Water

The freezing point study of raw and retail milk samples as reported in the Journal of Milk and Food Technology (July, 1976) has continued for retail samples. The Pennsylvania Department of Agriculture adopted a regulation which considers milk with a freezing point of above −0.525 C to be adulterated. A list of causes of added water was prepared and distributed to producer and processor groups in Pennsylvania.

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Freezing-Point Depression in Electrolytic Solutions

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s0370164600007987 ◽

1904 ◽

Vol 24 ◽

pp. 363-379 ◽

Cited By ~ 4

Author(s):

James Walker ◽

A. J. Robertson

Keyword(s):

Systematic Error ◽

Freezing Point ◽

Freezing Point Depression ◽

Freezing Points ◽

Ordinary Method

The following research was undertaken for the purpose of determining the freezing points of solutions under conditions which would involve a different systematic error from that encountered when the ordinary method of procedure is followed; and, secondly, for the purpose of obtaining ionisation values for electrolytic solutions by the cryoscopic method which should be made by compensation as far as possible independent of any systematic error in determining the freezing points.

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Freezing Resistance in Some Northern Populations of Pacific Herring, Clupea harengus pallasi

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f89-260 ◽

1989 ◽

Vol 46 (12) ◽

pp. 2104-2107 ◽

Cited By ~ 5

Author(s):

James A. Raymond

Keyword(s):

Sodium Chloride ◽

Freezing Point ◽

Clupea Harengus ◽

Serum Osmolality ◽

Pacific Herring ◽

Freezing Point Depression ◽

Freezing Resistance ◽

Freezing Points ◽

Clupea Harengus Pallasi ◽

Active Substances

Pacific herring, Clupea harengus pallasi, were collected at three locations in Alaska and Japan in winter and spring to determine their degree of freezing resistance. Herring collected from waters whose temperatures ranged between 4.7 and −1.4 °C showed serum freezing points between −1.22 and −1.40°C. All freezing points were below those expected from measurements of serum osmolality, indicating that a noncolligative antifreeze was present that added between 0.28 and 0.61° to the freezing point depression. In addition, osmotically active substances other than sodium chloride contributed to the freezing point depression. in some of the samples.

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