A METHOD FOR THE DETERMINATION OF THE FREEZING POINT DEPRESSION OF AQUEOUS SOLUTIONS PARTICULARLY THOSE CONTAINING PROTEIN

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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Water Activity and Freezing Point Depression of Aqueous Solutions and Liquid Foods

Journal of Food Science ◽

10.1111/j.1365-2621.1983.tb05056.x ◽

1983 ◽

Vol 48 (6) ◽

pp. 1667-1669 ◽

Cited By ~ 71

Author(s):

C. R. LERICI ◽

M. PIVA ◽

M. DALLA ROSA

Keyword(s):

Aqueous Solutions ◽

Water Activity ◽

Freezing Point ◽

Freezing Point Depression ◽

Liquid Foods

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A study of ionic association in aqueous solutions of bi-bivalent electrolytes by freezing-point measurements

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1955.0221 ◽

1955 ◽

Vol 232 (1190) ◽

pp. 320-336 ◽

Cited By ~ 50

Keyword(s):

Aqueous Solutions ◽

Potassium Chloride ◽

Dissociation Constants ◽

Freezing Point ◽

Ionic Association ◽

Freezing Point Depression ◽

Physical Status ◽

Copper Zinc ◽

Cobalt And Nickel

Measurements of freezing-point depression with a precision of ± 0-0002° C have been made on aqueous solutions of potassium chloride and the sulphates of copper, zinc, magnesium, calcium, cobalt and nickel. The results for the sulphates have been analyzed using the theory of incomplete dissociation in a manner which makes clear the physical status of the dissociation constants obtained, and the relation between the approaches associated with the names of Bjerrum and Davies. The values of the dissociation constants are compared with those obtained by other methods.

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