A COMPARISON OF RAW, PASTEURIZED, EVAPORATED, AND DRIED MILKS AS SOURCES OF CALCIUM AND

PHOSPHORUS FOR THE HUMAN SUBJECT.*

BY MARTHA M. KRAMER, ESTHER LATZKE, AND MARY MARGARET SHAW.

(From the Department of Food Economics and Nutrition, Division of Home Economics, Kansas Agricultural Experiment Station, Marshattan.)

(Received for publication, June 25, 1928.)

It has been generally recognized that milk serves as an excellent source of calcium and phosphorus in the diet. However, an in- creasing tendency toward the use of such forms as evaporated, dried, and especially pasteurized instead of raw milk makes it seem of value to determine whether or not the same reliance can be placed upon all forms of milk as sources of the minerals, calcium and phosphorus. Experiments here described were planned to add to the present rather limited knowledge concerning the availability of calcium and phosphorus from various forms of milk, fresh raw milk being used as a standard and both children and adults as subjects.

LITERATURE.

A search of the literature fails to reveal many metabolism experiments with the human subject for the study of the problem at hand. Further- more, almost none of the experiments had a definite standard for com- parison.

Willard and Blunt (I) have reviewed the more important studies made with both human and animal subjects; namely, the work of Washburn and Jones (2), Magee and Harvey (3), Daniels and Loughlin (4)! and Daniels and Stearns (5). These investigations point to the superiority of raw, evaporated, condensed, and quickly boiled milks over pasteurized milk. Willard and Blunt (1) made an extensive balance study, using pasteurized and evaporated milks. The children used as subjects all showed better retention of calcium and phosphorus when evaporated rather than pas- teurized milk was used. Increased retention on evaporated milk was shown by two of their four adult subjects.

* Contribution No. 6, Department of Home Economics.

233

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284 Utilization of Ca and I? from Milk

Ladd, Evarts, and Franks (6) made a study of the relative efficiency of certified and pasteurized milk for infant feeding by following the gains in weight made by a large number of subjects. They found that the certified milk allowed for better gains than the pasteurized, even when orange juice and cod liver oil were added. They raise the question whether the su- periority of the certified milk is due merely to the fact that it is raw or to the better balanced feeding of the cows.

Differences in availability of the minerals in the food seems even more important in the light of the report of Hart, Tourtellotte, and Hey1 (7) whose adult subject showed no increase in calcium retention as the result of irradiation or as the result of the administration of cod liver oil.

EXPERIMENTAL.

Calcium and phosphorus balance experiments were carried out in three series, both children (Series 1, conducted in Topeka) and adults (Series 2 and 3, conducted in Manhattan) being used as subjects. The same general plan was used throughout, changes being made only where experience indicated possible improve- ments. In all cases every effort was made to have milk the only variable in the experiment. Simple diets were planned, adequate in protein (8) and calories. Milk was made to furnish as much of the total calcium as possible. Milk also furnished much of the phosphorus, but its composition is such that it could not provide equally large proportions of both elements. In order that differ- ences might show, it seemed essential to keep the total intake of caIcium and phosphorus near the minimum required for main- tenance in the adults (8) and below the amount required for optimum storage in the children.

The children were given about 625 gm. of fresh milk daily and equivalent amounts of dried milk, this being below the figure for optimum storage suggested by Sherman and Hawley (9). Fresh milk furnished not less than 75 per cent and dried milk not less than 73 per cent of the total calcium. Almost half the phosphorus was supplied by the milk.

The adu1t.s in Series 2 received 222 gm. of fresh milk daily, with calculated equivalent amounts of the other forms during the various periods. Analyses later showed that the subjects received about 0.56 gm. of calcium per day. The milk furnished 47 to 52 per cent of the total calcium but only about one-fourth of the total phos- phorus. In Series 3 the fresh milk was increased to 260 gm. per day, but the diet was so changed as to bring the total calcium down

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Kramer, Latzke, and Shaw

to 0.50 gm. per day, which is nearer the minimum of 0.45 gm. set by Sherman (8). The milk furnished 68 per cent of the total calcium and 38 per cent of the total phosphorus.

As much as possible foods were chosen which could be purchased in quantity to last through an experiment so that the composition would not vary.

A standard brand of dried milk made by the spray process and also a popular brand of evaporated (i.e. unsweetened condensed) milk were chosen as examples of these products now in common use. These same commercial brands were used in all experiments. In Topeka the fresh milk was obtained from a commercial dairy marketing a product of very high grade. The fresh milk for Series 2 and 3 was obtained from the College Dairy. For Series 2 it happened that milk was available from two cows which had been kept in the dairy barn away from the sunlight for some months before coming fresh. The cows had been in the barn 5 months at the time the milk (called Fresh Milk B) was used for the experiments. The cows producing this milk were of the college herd and were receiving the same rations as the animals in the remainder of the herd from which the fresh milk for the experi- ments was obtained. For Series 3 milk pasteurized by the “hold” process was obtained from the College Dairy. It was pasteurized in the morning and used at noon. It was of exactly the same origin as the fresh milk used in the same series.

All experiments were divided into 3 day periods. Foods were weighed and records kept of daily consumption of subjects. Food samples of approximately the same size were taken daily, weighed, and dried or, in the case of liquids, preserved with formaldehyde for analysis. All samples of urine and feces were collected, car- mine being used to mark the feces of the various periods.

The McCrudden (10) method of analysis was used for calcium determinations of both food and feces for all series. Dry samples were ashed in an electric muffle furnace, and liquid samples with nitric acid.

For samples of Series 1 and 2 the phosphorus determinations were made by the gravimetric method of double precipitation, first as ammonium phosphomolybdate and then as magnesium ammonium phosphate. A volumetric method recommended by the Association of Agricultural Chemists (11) was used for deter-

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286 Utilization of Ca and P from Milk

mination of phosphorus in samples for Series 3. Magnesium nitrate was used for ashing. The methods used were tested for accuracy on samples of known composition. Analyses were made with the cooperation of the chemists of the Agricultural Experi- ment Station and the methods were those used by them in routine analyses. All analyses were made in duplicate.

Since the content of calcium and phosphorus varies within wide limits for most foods, analyses were made of all foods used, no figures being accepted from previously compiled tables (Table I).

TABLE I.

Food Analyses (Percentage of Edible Portion).

series 1. Series 2. Series 3.

Fp& Last two

Ca P periods.

Ca P

ca P Ca P -~---- --

Fresh milk .................. 0.1240.0240.1270.0230.1270.0230.1340.105 Fresh Milk B ............... 0.1250.025 Pasteurized milk ............ 0.1340.104 Driedmilk.. ................ 0.9150.1810.9760.176 0.9340.768 Evaporated milk ............ 0.2560.046 0.283 0.210 Apple ....................... 0.0330.004 Bread ....................... 0.0120.0200.0520.0190.0510.0260.0500.092 Butter ...................... 0.0170.0040.0280.0040.0300.004 Cocoa.. ..................... 0.0320.184 Rolled oats ................. 0.136 0.106 Orange juice ................ 0.0120.0060.0140.0520.0180.0050.0080.014 Potato ...................... 0.0220.0160.0320.0180.0260.0140.0060.042 Prunes. ..................... 0.0280.0310.0780.0160.0820.0250.0550.095 Lean ground beef ........... I I 0.0300.0510.0180.0500.0160.223

Series 1 (Started in October, 19W4).-Three girls and two boys, 7 to 12 years of age, served as subjects for this series. The feeding experiments were conducted in the Topeka Home of the Kansas Children’s Home Society where necessary facilities for the work were kindly provided. The children were examined by a physi- cian, a child specialist, and were pronounced suitable for the in- vestigation. The experiment was divided into the following periods: Period I, fresh milk; Period II, fresh milk; Period III, dried milk; Period IV, dried milk; Period V, fresh milk.

The regular hours of the institution were maintained for the

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Kramer, Latzke, and Sham 287

children used as subjects. Time spent in the open air, including walks to and from the public school a few blocks distant, remained practically uniform throughout the experiment. During the entire time only 2 days were cloudy, sunny fall weather typical of the region prevailing during the remainder of the time. The

TABLE II.

Series 1.

Eunice, female, age 12 yrs., weight 38.2 to 41.1 kilos.

Period No.. . , . . . . . . . . . . . 1 I ( II 1 III 1 IV 1 v

Average food intake for each period, in gm. per day.

Fresh milk .............. 662 Dried “ .............. Apple,E.P.*. ........... 208 Bread ................... 318 Butter .................. 90 Cocoa. .................. 5 Oats .................... 40 Orange juice ............. 57 Potat0,E.P.. ........... 198 Prunes, “ ............. 25 Sugar ................... 27 Calories ................. 2759 Protein .................. 66 Calcium. ................ 1.051 Phosphorus .............. 0.657

625 625

200 299 110

7 45 65

250 50 35

2919 66

1.030 0.684

82 82 200 217 384 325 110 150

7 7 45 45 65 65

250 250 50 50 27 20

3093 3232 74 69

1.018 1.023 0.711 0.692

200 299 93

4 45 65

250 50 22

2724 65

1.026 0.672

Ca output ............... 0.433 0.699 “ balance.. ............ +0.618 +0.331

P output ................ 0.254 0.272 “ balance. .............. $0.403 +0.412

Ca and P balances in gm. per day.

0.785 0.626 0.572 $0.233 $0.397 +0.454

0.374 0.352 0.354 $0.337 $0.340 +0.318

* E. P., edible portion.

nutritive condition of the children remained good throughout and each subject showed a satisfactory gain in weight.

The diet contained, daily, 625 gm. of fresh milk or its calculated equivalent in dried milk. Other foods were apples, cocoa, orange juice, prunes, potatoes, rolled oats, sugar, bread, and butter. The last two items were given in amounts desired but the other foods were kept nearly constant (Table II).

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288 Utilization of Ca and P from Milk

Series 2? (Started in February, 1926).-Four healthy young women who were instructors and graduate students served as subjects for the second series of experiments. The periods of the

TABLE III.

Series 2.

V. C., female, weight 63 kilos.

PeriodNo......l I / II ( III 1 IV 1 V 1 VI 1 VII 1 VIII

Average food intake for each period, in gm. per day.

Dried milk.. Fresh “ . . Evaporated

milk...... Fresh Milk

B . . . . Bread,

white..... Butter...... Orange

juice.. . Potato,

E. P.*. . Prunes,E. P. Beef, lean. . Sugar . . Calories.. . . Protein. . . Calcium. Phosphorus.

30 30 222 222

100 100

222 222

250 250 250 250 250 250 230 230 100 100 100 100 100 100 70 70

200 206 200 200 200 200 200 200

120 120 120 120 120 120 120 120 50 50 50 50 50 50 50 50 80 80 80 80 80 80 80 80 90 90 90 90 90 90 70 70

2391 2391 2392 2392 2406 2406 2029 2029 52 52 52 52 55 55 50 50

0.580 0.580 0.568 0.568 0.543 0.543 0.538 0.538 0.373 0.373 0.3711 0.371 0.360 0.360 0.393 0.393

Ca and P balances in gm. per day.

Ca output.. 0.686 0.680 0.580 0.581 0.536 0.545 0.650 0.655 “ balance. -0.106 -0.100 -0.012 -0.013 $0.007 -0.002 -0.112 -0.117

P output... 0.388 0.383 0.371 0.369 0.361 0.369 0.534 0.526 “ balance.. -0.015 -0.010 0.000 to.002 -0.001 -0.009 -0.141 -0.133

*E. P., edible portion.

experiment were as follows: Period I, dried milk; Period II, dried milk; Period III, fresh milk; Period IV, fresh milk; Period V, evaporated milk; Period VI, evaporated milk; Period VII, fresh milk B; Period VIII, fresh milk B.

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Kramer, Latzke, and Shaw

A diet was planned to follow closely that of the children, the calcium being reduced to the point where differences might be expected to show. The diet contained white bread, butter, orange juice, potatoes, prunes, lean ground beef, and sugar. Body weights of subjects were kept constant by adjusting the amounts of butter and sugar in the diets. Subjects remained indoors as

TABLE IV.

Sem’es 3.

I. B., female, weight 58.2 kilos.

Period No.. . -1 I 1 II 1 III 1 IV 1 v 1 VI .

Average food intake for each period, in gm. per day.

Pasteurized milk ..... 260 260 Raw milk ............ 260 260 Dried milk ........... 34 34 Bread. ............... 200 200 200 200 200 200 Butter fat ........... 90 90 90 80 80 80 Orange juice ......... 200 200 200 200 206 200 Potato, E. P.*. ....... 120 120 120 120 120 120 Prunes, “ ......... 35 35 35 35 35 35 Beef ................. 80 80 80 80 80 80 Sugar ................ 80 80 80 70 70 70 Calories. ............. 2244 2244 2244 2034 2027 2027 Protein .............. 48 48 48 48 48 48 Calcium ............. 0.503 0.503 0.503 0.503 0.472 0.472 Phosphorus .......... 0.711 0.711 0.711 0.711 0.702 0.702

Ca and P balances in gm. per day.

Ca output ........... 0.632 0.619 0.525 0.453 0.530 0.532 “ balance ........... -0.129 -0.116 -0.022 $0.050 -0.058 -0.060

P output ............. 0.813 1.057 0.692 0.800 0.693 0.766 “ balance ............ -0.102 -0.346 +0.019 -0.089 +0.009 -0.064

* E. P., edible portion.

much as possible, so that the factor of exposure to sunlight was almost eliminated (Table III).

Series 3 (Started in February, 1928).-Four healthy young women who were instructors and graduate students served as subjects for the third series of experiments, which was conducted in the late winter as was the second series. The general plan of the experiments was much the same. The periods were : Period I,

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290 Utilization of Ca and P from Milk

pasteurized milk; Period II, pasteurized milk; Period III, fresh milk; Period IV, fresh milk; Period V, evaporated milk for two subjects and dried milk for two subjects; Period VI, evaporated milk for two subjects and dried milk for two subjects.

Profiting by the previous experiments, we made a few changes. In the first place, the diet was so planned that a larger per cent of the total calcium would be furnished by the milk. The total intake of calcium was somewhat lower than in Series 2, bringing

TABLE V.

Series 1. Calcium and Phosphorus Balances in Gm. per Day (Average of Periods Used).

I I Calcium.

I Phosphorus.

Subject.

Eunice, 12 yrs., 40 kilos.

Kind of milk.

Bal- B& Ill- Out- Bal- ante In- Outr Bal- anm

take. put. ante. Per Per kg.

take. put. ante. kg.

---__-----

Fresh. 1.0320.5680.4640.0120.6710.2930.3780.009 Dried. 1.0250.7060.3190.0080.7020.3630.3390.008

Jack, 9 yrs. 8 mos., Fresh. 1.0660.7610.3050.0100.6540.3910.2630.008 32 kilos. Dried. 0.9390.7320.2070.0070.6280.4730.1550.005

Lottie, 8 yrs. 3 mos., 26 kilos.

Fresh. 1.0430.4930.5500.0210.6820.3720.3100.012 Dried. 0.9910.5960.3950.0150.6660.4250.2410.009

Nellie, 10 yrs. 6 mos., 28.3 kilos.

Fresh. 1.0370.3250.7120.0250.6520.2620.3900.014 Dried. 0.9780.6030.3750.0130.6390.3570.2820.010

Wayne, 7 yrs. 4 mos.

the figure nearer the minimum requirement of 0.45 gm. suggested by Sherman (8). Also, more rigid rules were set up for the con- sumption of food by the subjects. All subjects ate the same foods at the same time of day. All milk was consumed, without heating, as a beverage at the noon meal. The pasteurized and raw milks, which came from the College Dairy, were never older than of the milking of the previous night.

All subjects remained indoors as much as possible, although there was little sunny weather during the time of the experiment.

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TABL

E VI

. ,..

.

se

raes

8.

Ca

lcium

an

d Ph

osph

orus

Ba

lanc

es

in

Gm.

per

Perio

d (A

vera

ge

of

Perio

ds

Used

).

Subj

ect.

M.

D.,

weigh

t 56

kil

os.

R.

T.,

weigh

t 69

.5

kilos

.

V.

C.,

weigh

t 63

kil

os.

M.

K.,

weigh

t 53

.5

kilos

.

Kind

of

m

ilk.

Inta

ke.

Out

put.

Balan

ce.

Fres

h.

1.73

0 1.

487

$0.2

43

Dried

. 1.

773

1.74

8 $0

.025

Ev

apor

ated

. 1.

649

1.58

9 SO

.060

Fres

h.

1.70

4 1.

416

+0.2

88

Dried

. 1.

740

1.58

3 +o

. 15

7 Ev

apor

ated

. 1.

629

1.47

8 +0

.151

Fres

h.

1.70

4 1.

742

-0.0

38

Dried

. 1.

740

2.04

9 -0

.309

Ev

apor

ated

. 1.

629

1.62

2 $0

.007

Fr

esh

Milk

B.

1.

614

1.95

8 -0

.344

Fres

h.

1.64

7 1.

517

+0.1

30

Dried

. 1.

689

1.77

8 -0

.089

Ev

apor

ated

. 1.

587

1.42

2 +0

.165

Fr

esh

Milk

B.

1.

614

1.64

7 -0

.033

Calci

um.

Phos

phor

us.

FkhlC

e pe

r kg

.

$0.0

04

0.00

0 +0

.001

$0.0

04

+0.0

02

+o.o

oa

-0.0

01

-0.0

05

0.00

0 -0

.005

$0.0

02

-0.0

02

f0.0

03

-0.0

01

Inta

ke.

1.12

1 1.

130

1.08

8

1.11

3 1.

119

1.08

0

1.01

3 1.

119

1.08

0 1.

079

1.08

3 1.

091

1.05

6 1.

179

I

-- -

outp

ut.

1.03

4 1.

145

1.02

9

1.05

3 1.

133

1.07

0

1.01

0 1.

157

1.09

5 1.

590

1.05

8 1.

085

0.94

7 1.

548

Balan

ce.

$0.0

87

-0.0

15

$0.0

59

SO.0

60

-0.0

14

+0.0

10

+0.0

03

-0.0

38

-0.0

15

-0.5

11

$0.0

25

$0.0

06

$0.1

09

-0.3

69

BalaW

Z pe

r kg

.

+0.0

02

g 0.

000

to.0

01

3 r $0

.001

s

0.00

0 I%

0.

000

,cD

0.00

0 $

-0.0

01

@

0.00

0 u2

-0.0

08

F 8 0.

000

0.00

0 $0

.002

-0

.007

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TABL

E VI

I.

Serie

s 9.

Ca

lcium

an

d Ph

osph

orus

Ba

lanc

es

in

Gm.

per

Perio

d (A

vera

ge

of

P&o&

Us

ed).

Subje

ct.

Bind

of m

ilk.

E.

L.,

weigh

t 53

.6

kilos

.

I. B.

, we

ight

58.2

kil

os.

A.

L.,

weigh

t 68

kil

os.

M.

K.,

weigh

t 56

.3

kilos

.

Intak

e.

Fres

h.

1.47

4 Dr

ied.

1.38

2 Pa

steur

ized.

1.

509

Fres

h.

Dried

. Pa

steur

ized.

1.50

9 1.

417

1.50

9

Fres

h.

1.50

9 Ev

apor

ated

. 1.

525

Paste

urize

d.

1.50

9

Fres

h.

1.50

9 Ev

apor

ated

. 1.

525

Paste

urize

d.

1.50

9

- _-

-

Calci

um.

-r

outpu

t. B&

XlfX.

Int

ake.

outp

ut.

Balan

ce..

1.23

4 f0

.240

$0

.004

2.

064

2.05

0 f0

.014

0.0

00

1.65

3 -0

.271

-0

.005

2.

038

2.04

8 -0

.010

0.0

00

2.23

6 -0

.727

-0

.014

2.

133

2.55

1 -0

.418

-0

.008

1.46

8 +0

.041

+0

.001

2.

133

2.23

8 -0

.105

1.

593

-0.1

76

-0.0

03

2.10

7 2.

188

-0.0

81

1.87

6 -0

.367

-0

.006

2.

133

2.80

4 -0

.671

1.88

1 -0

.372

-0

.005

2.

133

2.03

2 $0

.101

1.

556

-0.0

31

0.00

0 2.

110

2.09

2 $0

.018

1.

883

-0.3

74

-0.0

06

2.11

0 2.

092

$0.0

18

1.55

0 -0

.041

-0

.001

2.

133

2.23

6 -0

.103

1.

318

+0.2

07

+0.0

04

2.11

0 1.

835

$0.2

75

1.80

3 -0

.294

-0

.005

2.

133

2.34

8 -0

.215

-0.0

02

-0.0

01

-0.0

12

$0.0

01

0.00

0 0.

000

-0.0

02

$0.0

05

-0.0

04

Phos

phoru

s.

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Kramer, Latzke, and Shaw 293

One subject only had received cod liver oil and that had been some weeks before the experiment started.

The foods selected for the diet were white bread, potatoes, ground lean round of beef, prunes, orange juice, sugar, butter fat, and milk. Quantities of butter fat and sugar were adjusted so that the subjects remained constant in weight (Table IV).

TABLE VIII.

Comparisons of Balances of Calcium per Kilo per Period of Subjects on Various Kinds of Milk.

The balance of each subject on raw milk was taken as his or her stand- ard or zero for the comparisons tabulated below.

Series 1. Eunice ......................... Jack ........................... Lottie ......................... Nellie .......................... Wayne .........................

Series 2. M. D .......................... R. T, .......................... v. c. .......................... M. K. .........................

Series 3. I. B ........................... E. L ........................... M. K. ......................... A. L. ..........................

Averages. Series 1 (children). ............. Series 2 (adults). .............. Series 3 (adults). .............. For all adults ..................

- -

-0.007 -0.018 -0.004 -0.001

-0.008 -0.008

DISCUSSION.

Dried.

-0.012 -0.009 -0.018 -0.036 -0.012

-0.004 -0.002 -0.004 -0.004

-0.004 -0.009

-0.017 -0.004 -0.007 -0.005

-

--

-

Evap- Fresh orated. milk B.

-0.003 -0.002 $0.001 +0.001

+0.005 f0.005

-0.001 to.005 +0.001

-0.004 -0.003

-0.004

-0.004

The experiment with children showed good storage of calcium from fresh milk not only at the beginning of the experiment but at the end also when the fresh milk period was repeated. During

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294 Utilization of Ca and P from Milk

the dried milk periods the diets contained almost as much calcium and a little more phosphorus than during the fresh milk periods. However, figures show the calcium retention of the various chil- dren to have averaged only 53 to 71 per cent as much as during their fresh milk periods, although the dried milk periods furnished an average of 94.5 per cent as much calcium as did the fresh milk periods. Likewise the phosphorus retention was somewhat lower. It is thus evident that the child retains more calcium when it is supplied in fresh milk than when furnished in equal amounts by dried milk, other factors remaining unchanged (Table V).

The adult subjects in Series 2 and in Series 3 were at all times receiving close to the minimum amounts of calcium and phospho- rus, sometimes showing negative balances and sometimes positive. (Tables VI and VII). Calculations have been made to show the calcium and phosphorus balances of each subject in gm. per kilo of body weight per period, averaged for like periods. The 3 day period was used, rather than the day, as the figures are necessarily rather small. Comparisons were then made, subject by subject, in each case the balance of a subject on fresh milk being taken as zero and the balances on other milks being listed as higher and lower or plus and minus in comparison with this fresh milk figure (Table VIII).

As with the children, dried milk gave for all subjects a lower calcium balance than did the fresh milk. Pasteurized milk, used in Series 3, gave a lower calcium balance than did fresh milk. On the other hand evaporated milk, used in both Series 2 and 3, gave a higher calcium balance for four of the six subjects. In Series 3, the most carefully controlled experiments, the subjects showed distinctly better calcium balances on evaporated milk than on fresh mi1.k. In Series 2, Fresh Milk B, secured from cows kept in the barn for 5 months, gave far lower calcium balances than did the herd fresh milk. Utilization of calcium from this milk was only about as good as the utilization of calcium from the dried milk.

Since the amount of milk used furnished smaller proportions of the phosphorus of the diet, the results on phosphorus are neces- sarily less convincing. They follow in general the results for calcium.

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Kramer, Latzke, and Shaw

SUMMARY AND CONCLUSIONS.

Metabolism experiments have been conducted with children and adults as subjects in an effort to learn whether or not the cal- cium and phosphorus in various forms of milk are equally available for human nutrition.

Results of experiments with five children make it evident that the child retains more calcium when it is supplied in fresh milk than when it is furnished in equal amounts by dried milk, other factors remaining unchanged.

All adult subjects showed more favorable calcium balances when the fresh milk was the source of supply rather than dried milk. Pasteurized milk also gave less favorable calcium balances than did fresh milk. Further, the milk from cows kept in the barn (Fresh Milk B) gave less favorable calcium balances than did fresh milk.

On the other hand adult subjects using evaporated milk showed balances at least as good as when fresh milk was used.

In general phosphorus balances followed the trend of the cal- cium balance figures.

BIBLIOGRAPHY.

1. Willard, A. C., and Blunt, K., J. Biol. Chem., 1927, lxxv, 251. 2. Washburn, R. M., and Jones, C. H., Vermont Agric. Exp. Station Bull.

196, 1916. 3. Msgee, H. E., and Harvey, D., Biochem. J., 1926, xx, 885. 4. Daniels, A. L., and Lough@ R., J. Biol. Chem., 1929, xliv, 381. 5. Daniels, A. L., and Stearns, G., J. Biol. Chem., 1924, lxi, 225. 6. Ladd, M., Evarts, H. W., and Franks, L. W., Arch. Pediat., 1926, xliii,

380. 7. Hart, M. C., Tourtellotte, D., and Heyl, F. W., J. Biol. Chem., 1928,

lxxvi, 143. 8. Sherman, H. C., Chemistry of food and nutrition, New York, 3rd

edition, 1926. 9. Sherman, H. C., and Hawley, E., J. Biol. Chem., 1922, liii, 375.

10. McCrudden, F. H., J. Biol. Chem., 1911-12, x, 187. 11. Official and tentative methods of analysis of the Association of Official

Agricultural Chemists, Washington, 1925.

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Margaret ShawMartha M. Kramer, Esther Latzke and Mary

THE HUMAN SUBJECTCALCIUM AND PHOSPHORUS FOR

DRIED MILKS AS SOURCES OFPASTEURIZED, EVAPORATED, AND

A COMPARISON OF RAW,

1928, 79:283-295.J. Biol. Chem. 

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