Special Studies of Methods of Canning Beef Made in Bureau of Chemistry

Composition of Beef Used for Canning.

—Samples of fresh beef intended for canning purposes, and examined in the Bureau of Chemistry, have the following composition:

Water, 71.17 percent

Insoluble protein, 13.87 „

Globulins, 1.38 „

Proteoses, peptones, and gelatin, 1.31 „

Meat bases, 1.09 „

Fat, 9.89 „

Ash, .96 „

Salt, .04 „

Undetermined, .33 „

The sample, of which the above data are representative, was secured from a mass of meat weighing 356 pounds, after passing through a sausage grinder and being thoroughly mixed. The above data may therefore be regarded as the representative constituents of the usual grade, most carefully selected canning beef.

Effect of Parboiling.

—A similar lot of meat secured in the same way and from the same carcass weighed 358 pounds and was parboiled as follows: The meat was placed in water in a steam-jacketed tank, the temperature of which stood at 196 degrees F. The reduction in the temperature caused by the meat was restored by heating the contents of the retort, and it was kept at 196 degrees F. for 15 minutes. It is thus seen that this parboiling was accomplished at a temperature below the boiling point of water. After the parboiling was completed it was found that the meat weighed 235 pounds, showing a net shrinkage in weight of 123 pounds. This sample of meat was then tinned in two-pound cans with the addition to each can of two ounces of canning jelly of the following composition:

Water, 95.18 percent

Protein, 1.75 „

Common salt, 2.85 „

Ash, .22 „

After sterilizing, the cans were opened and the contents subjected to analysis. The data obtained are as follows:

Water, 62.47 percent

Total protein, 24.88 „

Insoluble protein, 22.25 „

Proteoses, peptones, and gelatin, 2.63 „

Meat bases, 1.15 „

Fat, 9.87 „

Ash, .91 „

Salt, .19 „

Composition of Parboiling Water.

—The liquor, after parboiling the above sample, weighed 280 pounds and had the following composition:

Water, 99.12 percent

Protein, .06 „

Meat bases, .25 „

Ash, .25 „

Salt, .05 „

The above data show that the general effect of parboiling upon the canned meat is to diminish its content of water. Only a small quantity of the soluble proteids is found in the liquor, and the other principal constituents removed, aside from water, are the meat bases and mineral content or ash. The fat in the soup liquor was not determined because it rises to the surface and is not in any sense a constituent of the liquor itself. Considerable quantities of fat were removed in parboiling, the amount depending largely upon the temperature. At a low temperature of parboiling, such as described, the amount of fat secured is far less than when the temperature of parboiling is higher.

Table Showing the Comparative Effect of Parboiling and Sterilizing upon the Fresh Beef.

Constituents. Fresh Beef. Extracted
by
Boiling. Added
in
Canning. Composition
of
Canned Beef
as
Determined
by
Analysis.

Lbs. Lbs. Lbs. Lbs.

Water, 254.8 122.1 14.1 146.8

Protein, 59.3 .1 .1 58.5

Meat bases, 3.9 .7 .0 2.7

Fat, 35.4 12.2 .... 23.2

Ash, 3.4 .7 .2 2.1

Salt, .1 .1 .2 .4

Undetermined, 1.2 .... .... 1.7

Total, 358.1 .... .... 235.4

Preparation of Canned Beef with More Intensive Parboiling.

—In another experiment, determining the effect of the changes produced upon the fresh meat, more vigorous preparatory operations were performed. Samples were secured from eight healthy carcasses for use in this determination. Half of the sample was reduced to sausage and secured for analysis as described, and the other submitted to parboiling, sterilizing, and analysis.

Composition of the Sample of Fresh Meat.

Water, 69.33 percent

Total protein, 16.81 „

Insoluble protein, 12.69 „

Globulins, 3.06 „

Proteoses, peptones, and gelatin, 1.06 „

Meat bases, 1.12 „

Fat, 10.68 „

Ash, 1.13 „

Salt, .24 „

The original sample represented over a thousand pounds. The opposite sides of the carcasses were prepared for canning and produced the following amount of articles as sold on the market:

Total weight of half carcasses, 1,761 pounds

3 ribs, 53 „

5 rolls, 43 „

5 loins, 166 „

3 tenderloins, 13 „

3 sirloin butts, 28 „

3 boneless strips, 24 „

8 rump butts, 36 „

8 flank steaks, 8 „

8 kidneys, 9 „

24 beef hams, 261 „

Shank meat, 85 „

Soft bones, 198 „

Shank bones, 107 „

Tank tallow, 132 „

Canning meat, 598 „

The above data show that only about one-third of the whole carcass is suitable for canning purposes. The best and juiciest pieces, it is noticed, are cut away and sold for other purposes. In explanation of the above data it should be stated that only the fore-quarters of the carcass were used and not the whole carcass.

In the preparation of the sample for analysis, the same selection was made as for canning, and only the canning meat was used in the preparation of the sample.

Parboiling.

—The parboiling of this sample was accomplished in the following manner: The meat was first placed in cold water, 50 degrees F., and heated by means of injected steam. In five minutes the temperature had reached 122 degrees F., and at the end of eleven minutes the boiling temperature was reached and continued for one hour. The soup liquor resulting from the parboiling weighed 1,500 pounds and had the following composition:

Water, 99.08 percent

Protein, .09 „

Meat bases, .23 „

Ash, .28 „

Salt, .11 „

These data show that, as in the other cases, the chief extraction from the meat during parboiling is water and the next most important removal is of meat bases and mineral matter or ash. After sterilization in the usual way the cans were opened and the canned beef subjected to analysis. The composition of the canned beef was as follows:

Water, 56.18 percent

Total protein, 31.57 „

Insoluble protein, 27.94 „

Proteoses, peptones, and gelatin, 3.63 „

Meat bases, 1.44 „

Fat, 7.72 „

Ash, .82 „

Common salt, .04 „

Composition of the Fresh and Canned Meat.

—Below is found a table similar to that already given for the other sample, showing the composition of fresh beef and the resulting canned beef.

Constituents. Fresh Beef. Extracted
by
Boiling. Added
in
Canning. Composition
of
Canned Beef
as
Determined
by Analysis.

Lbs. Lbs. Lbs. Lbs.

Water, 414.6 243.2 12.9 184.3

Proteins, 100.5 1.3 .... 101

Meat bases, 6.7 3.4 .... 4.6

Fat, 63.9 39.2 .... 24.7

Ash, 6.8 4.2 .... 2.6

Undetermined, 5.5 .... .... 2.8

Total, 598 .... .... 320

From the above table it is seen that the shrinkage during parboiling amounts to 46.49 percent of the weight of the fresh meat. Of this shrinkage 82.85 percent is water, 14.11 percent is fat, 1.51 percent ash, and 0.82 percent meat bases. It is noticed that more than half of the water originally found in the meat is extracted by parboiling.

It seems rather anomalous that boiling a substance with water would extract water from it, but in the case of meats it is seen that half the water, or even more, which a meat contains is extracted from it by boiling in water.

The two samples given are extreme cases in the method of preparing meats for canning. In the first instance the meat is placed at once into hot water just below the boiling point and kept there for only a short time. In the second case the meat is placed in cold water and is brought to the boiling point and maintained there for one hour. In the last case the low temperature of the water in which the meat was originally placed favors the extraction of a portion of the soluble protein matter, namely, albumins, globulins, etc., while, on the other hand, the long-continued boiling to which it was subjected tends to decompose the connective tissues of the meat and causes the loss of small particles of the insoluble protein thus separated by disintegration. Although in the last case the shrinkage was much greater than in the preceding experiment, practically no insoluble protein matter was extracted, mechanically or otherwise.

Canning of Beef without Parboiling.

—To determine the amount of shrinkage which takes place and the general effect which is produced by canning meats without parboiling, samples were prepared, sterilized, and canned in the usual way, with the exception of the omission of parboiling. On opening the cans it was found in each case that the meat had shrunk to about two-thirds of its former volume and that the place was occupied by a liquid containing a number of particles of solid matter. The appearance of the sample was much less inviting than that of meat canned after parboiling.

An analysis of the sample was made, with the following results: Total weight of sample, 31 ounces; weight of canned meat, 21 ounces.

Water, 63.83 percent

Protein, 27.25 „

Meat bases, 1.09 „

Fat, 4.62 „

Ash, 1.01 „

Salt, .04 „

Undetermined, 1.20 „

Composition of Liquid.

—The liquid in the can was examined with the following result: Weight of liquor, 10 ounces.

Solids, 6.93 percent

Protein and gelatin, 1.94 „

Meat bases, 1.84 „

Ash, 1.22 „

Salt, 1.15 „

The above data show that the beef lost 32.06 percent of its weight in the canning, a little over half of which is water.

It appears that less protein matter is extracted when the meat is parboiled by being plunged into boiling water than when it is packed in a can without parboiling and subsequently subjected to the temperature of sterilization. In the former case the soluble proteins in meat near the surface are coagulated before they can diffuse into the surrounding water. In the other case, owing to the low conductivity of meat, the temperature at the surface of the can penetrates slowly to the interior and the juices which are extracted from the meat carry with them protein matter in solution which is afterwards precipitated by heat and remains in the liquid as matter coagulated at the temperature of sterilization.

It is seen that parboiling has many advantages. It extracts less of the valuable matter from the meat, it shrinks the meat before packing so that the tins contain more nutrient matter, and it improves the appearance of the meat to the consumer when opened.

Relation of Canned to Fresh Meat.

—In the following table is given the number of ounces of canned meat in a number of cans compared with the equivalent amount of fresh beef used in filling them:

No.
of Can. Canned
Beef, Equivalent
to Fresh Beef.

Ounces. Ounces.

1, 29 44.2

2, 29.9 42.6

3, 28.5 38.7

4, 12.6 19

5, 30.5 57

6, 30.6 50.9

Means, 26.9 42.1

It thus appears that a can of 26.9 ounces of beef contains, as an average content, an amount of meat equivalent to 42.1 ounces of fresh beef, and retains practically all of the nutrient value of the larger quantity of fresh beef.

Canned Ham and Bacon.

—It seems unnecessary, as a rule, to can ham and bacon properly cured and transported in a suitable manner. There are occasions justifying the use of these products in tropical countries and in other places far remote from the sources of manufacture, and where the preservation of them, by reason of the character of the climate, is difficult.

The proper preparation of these articles, packing in tins and sterilizing, makes it possible to send them to the most distant points and to have them consumed in the most unfavorable climatic conditions. Canned ham, as it is found upon the market, has a higher percentage of fat and a consequently lower percentage of protein than canned beef. The ham is packed closely and the smaller pieces added for the purpose of filling up interstices between the larger pieces of meat and keeping the can full. It is reasonable to infer that the added meat is pork, although very probably it may not always be so.

Composition of Canned Ham and Bacon.

—The character of the canned ham and bacon upon the market may be illustrated by the composition of the following samples (these samples were purchased in the open market and are presumably representative of the products as commonly sold in the shops):

COMPOSITION OF CANNED HAM AND BACON.

Description. Composition of
Original Material. Composition of
Dry Material.

Water. Water
in
fat-
free
sub-
stance. Fat. Nitrogen. Nitrogenous
substances. Ash. Sodi-
um
chlo-
rid. Total. Pro-
tein
(N ×
6.25). Fat. Ash. Sodi-
um
chlo-
rid.

Total. Co-
agu-
lated
pro-
teids. Precip-
itated
by
bromin. Meat
bases. Pro-
tein
(N ×
6.25). Co-
agu-
lated
pro-
teids. Gelati-
noids
and
pro-
teids
precip-
itated
by
bromin. Meat
bases.

P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct. P. ct.

Sliced Star ham, 43.80 71.84 38.22 2.07 1.62 0.06 0.39 12.94 10.12 0.38 1.22 3.86 3.29 97.60 23.00 68.01 6.87 5.85

Boneless ham, 53.30 64.09 16.84 3.75 3.15 .10 .50 23.44 19.69 .62 1.56 5.43 4.34 97.54 50.19 36.06 11.63 9.29

Gold Band sliced ham, 48.37 68.72 29.78 2.82 1.89 .09 .84 17.62 11.81 .56 2.62 5.03 4.10 98.07 34.06 57.58 9.72 7.93

Boneless cooked ham, 41.53 63.50 34.60 3.03 2.50 .12 .41 18.94 15.62 .75 1.28 4.33 3.66 98.25 32.38 59.17 7.40 6.26

Prosciutto Scelto in Fette, 36.77 57.27 35.79 3.05 1.96 .19 .90 19.06 12.25 1.19 2.81 8.37 7.51 97.38 30.12 56.60 13.24 11.88

Lunch ham, 40.74 59.53 31.56 3.68 3.21 .16 .31 23.00 20.06 1.00 .97 3.84 3.08 98.26 38.81 53.26 6.48 5.19

Huckins sandwich ham, 36.56 72.17 49.34 2.04 1.77 .07 .20 12.75 11.06 .44 .62 1.75 .. 99.79 20.13 77.77 2.76 ..

Ham, “Coin Special,” 50.87 69.12 26.42 2.94 2.55 .34 .05 18.38 15.94 2.12 .16 3.55 2.39 99.09 37.37 53.77 7.23 4.86

Sliced Star bacon, 15.34 21.24 27.79 6.68 4.75 .74 1.19 41.75 29.69 4.62 3.72 15.02 13.28 96.28 49.31 32.82 17.74 15.69

Beechnut bacon, 18.59 26.42 29.59 5.74 4.10 .26 1.38 35.88 25.62 1.62 4.31 19.90 17.84 99.63 44.06 36.35 24.44 21.91

Sliced breakfast bacon, 20.73 67.06 69.07 1.07 .92 .07 .08 6.69 5.80 .44 .25 3.06 2.37 99.41 8.44 87.13 3.86 2.99

Gold Band sliced bacon, 19.69 62.99 68.74 1.40 .91 .10 .39 8.75 5.69 .62 1.22 2.57 2.27 98.55 10.87 85.60 3.20 2.83

Fresh pork, rib and loin, 51.80 78.32 33.86 2.15 1.57 .25 .33 13.44 9.81 1.56 1.03 .78 Tr. 98.88 27.87 70.25 1.62 Tr.

Adulteration of Canned Ham and Bacon.

—From the above data it is seen that the products are probably true to name, and are actually ham and bacon. The principal adulterations which are found in these articles are preservatives and coloring matters. The coloring matter usually found is saltpeter which, in one instance, was present in quantities of one-tenth of one percent and the average quantity found was one-twentieth of one percent. Saltpeter is not used as a preservative, although it is often claimed by packers that such is the case. In the minute quantities in which it is employed it has little or no effect as a preservative if, indeed, it could be deemed a germicidal substance. The principal preservative which is found is boric acid. In fourteen cases examined, however, only two contained this preservative, which shows that there is no necessity for its use on any occasion. Under the new meat inspection law all meat products prepared for interstate and foreign commerce are packed under direct supervision of the Department of Agriculture, and contain no harmful color and no chemical preservative.

Canned Tongue.

—Several varieties of canned tongue are found upon the market known as ox tongue, lamb tongue, luncheon tongue, etc. The tongues of calves, steers, sheep, lambs, and swine are the ones which are usually canned, and they may be previously pickled before canning. The average composition of the canned tongue upon the market is shown from the following data based upon the examination of seventeen samples:

Water, 55.17 percent

Fat, 20.23 „

Protein, 19.43 „

Meat bases, 1.23 „

Glycogen, .24 „

Total ash, 3.71 „

Of which common salt, 2.90 „

The data show that in the canning of tongue a large quantity of fat is present, more than the true part of the tongue contains. Nearly all of the samples examined contained saltpeter, the largest quantity found being .15 percent.

Adulteration of Canned Tongue.

—It is not probable that any meat, except the tongue itself, is used for canning, but the contents may not be true to name. The fat dressing employed is not specified, and probably its character and amount rest alone with the ideas of the manufacturer relative thereto. Presumably the fat should be of the same animal as the tongue. A critical examination of the fat will, however, reveal whether or not this is the case.

Saltpeter is the most common adulteration, and is used solely to impart or preserve the red color of the fresh meat. Boric acid is also occasionally employed. One of the samples contained boric acid.

Without inspection of the process of manufacture, it is not possible to be assured of the sanitary conditions of the meats which are sold as canned tongue and also of the sanitary conditions of the canning itself. These are all matters of the highest importance to the consumer, and should be attested by proper inspection certificates. Under the new meat law only the proper articles can be certified by the officials in charge of inspection.

Examination of Fat as a Test for Adulterations.

—It is evident, from what has already been said, that the character of the fats which are used in the canning of preserved meats is not always the same as that of the meat to which they are added. A careful study has been made in the Bureau of Chemistry of the fats extracted from different canned meats. The chemical and physical characteristics of these fats are given in the following table:

Source
of
Fat. Melting
Point. Chilling
Point. Iodin
Number. Maumené
Number. Degrees
Butyro-
refracto-
meter.

C.° C.° C.°

Canned roast beef, 36.5-43.9 27.8-37.0 36.1-50.6 35.6-36.0 47.0-55.5

Canned smoked beef, 37.7-41.8 22.0-29.0 50.9-57.5 .. 51.0-58.5

Canned ham and bacon, 23.6-30.5 17.5-24.0 48.5-68.2 39.8-43.5 49.0-58.2

Fowl, 28.0-34.0 12.0-36.5 67.0-86.4 38.9-52.0 49.0-62.5

It has been noticed that the crystals deposited by the evaporation of the ether solution of chicken fat resemble beef stearin in shape, but are much smaller and more delicate. It is seen that the melting point of fat in ham and bacon is rather lower than in leaf lard. It is evident, therefore, that this fat is not lard or, at least, not wholly composed of the best lard, but probably consists of the fat not usually employed for lard making.