Campbell's book; canning, preserving and pickling, by Clyde H. Campbell ...
Main Author: Campbell, Clyde H
Published: [Chicago, Vanco publishing corp., publishers of the Food packer] 1937 [i.e. 1945]
Canning and preserving > Bibliography
Canning and preserving
SAUERKRAUT is the product made by the lactic fermentation of shredded cabbage in a weak salt solution. The United States Department of Agriculture definition for sauerkraut is as follows:
"Sauerkraut is the clean, sound product, of characteristic acid flavor, obtained by the full fermentation, chiefly lactic, of properly prepared and shredded cabbage in the presence of not less than two per cent (2%) nor more than three per cent (3%) of salt. It contains, upon completion of the ferment-ation, not less than one and one-half per cent (1.6%) of acid, expressed as lactic acid. Sauerkraut which has been rebrined in the process of canning or repacking contains not less than one per cent (1%) of acid, expressed as lactic acid."
The importance of kraut as a food is so great that it is not amiss to state some of its important values: On account of its sharp, acid character, it is quite palatable and appetizing. It contains lactic, which aids in digestion and regulates the removal of waste materials from the body, stimulates the normal action of the intestines, and prevents the growth of harmful bacteria which sometimes causes auto-intoxication. Being rich in vitamins, it is a preventive of scurvy, and is also a therapeutic in cases of diabetes, excess of uric acid and other diseases. Some have used it successfully in reducing high blood pressure.
The juice from the kraut is especially appetizing and is served in many hotels as a cocktail.
The average composition of cabbage is:
Crude fiber 1.10
Total carbohydrates 5.60
Cabbage, in addition to containing lime, potash, phosphates, and iron, contains vitamins A, B, and C. The protein and minerals in the ash act as food to sustain the fermentation. This fermentation converts the sugar to lactic acid, and in addition to this, there is formed alcohol, acetic and butyric acids in small amounts. The amount of lactic acid produced depends upon the amount of sugar, protein and minerals present. Weather conditions and heat will, to a certain extent, control the rapidity of the fermentation.
Cabbage used in making kraut should be firm, and only sound heads fully matured with the outer green leaves removed. There is a difference of opinion as to the best variety to be used in making kraut. Dutchess, All Season, Succession, Glory, and Copenhagen are varieties that are often used.
Cabbage is usually stored in bins or cribs outside the plant where there can be a free circulation of air. This prevents excess wilting, heating, and the development of putrefying bacteria. It is necessary that the cabbage wilt some, otherwise in cutting, the cabbage will be too brittle and break into small pieces instead of giving the proper "shred." The heads can be transferred by means of an endless belt or conveyor to help those who core, and remove the green, withered, and dirty outside leaves. Washing the cabbage before cutting is considered beneficial because it removes the undesirable bacteria (such as the objectionable soil bacteria) on the sur face of the cabbage, while the bacteria that are desirable are within the head and not removed by washing.
The core is not removed, but cut or sliced very fine by rapid revolving conical blades. The outer leaves that are removed are dropped on an endless belt that conveys them outside the coring room, where they are hauled away either to an incinerator, or to farms where they are ploughed under shortly after being dumped.
The cored cabbage is conveyed by belts to the shredders where it is cut into very fine shreds and again conveyed by belts to trucks or carts, where it is salted before being dumped. The cabbage may be given a thin or thick cut according to the judgment of the manufacturer. A fine shred, long cut, makes a better appearance than a coarse, medium cut. An objection to the fine shred, long cut, is that it packs too tightly and cooks to pieces. Set the knife blades about the thickness of a five cent piece (about 1/16 of an inch) to produce a good thickness. Different plants have different layouts that require modifications in handling. Instead of salting in carts, salting may be done as the cabbage is being dumped from conveyors into the tanks.
Salting at the rate of 3 to 3½ pounds per 100 pounds of cut cabbage will give very good results, but some prefer salting at the rate of 2½ pounds per 100 of cabbage.
One of the secrets of well cured uniform kraut is due to proper and careful scattering of the salt. Lack of uniformity may permit the development of wild yeast and putrefying bacteria. A medium ground packers salt gives the best results. Before filling, the tanks should be clean and sweet. Clean them in the same manner as pickle tanks are cleaned. If possible, a concrete floor should be placed in the fermentation room. Tanks should be raised high enough to permit washing and spraying underneath. Also space should be allowed between them to permit passage. The ferment-ation room should be kept clean and sweet, and whenever possible the air should be changed by opening the doors and windows even if only for a "short time during the warmest part of the day. Unless the cabbage which falls to the floor is swept up, it will in time start decomposition. The air be-coming ladened with bacteria that cause this offensive odor may contaminate good tanks. Disinfectants should be used, but should be of such a nature that they will not have an odor that may permeate the air to such an extent that the kraut will absorb it. Dilute hypochlorite solution sprayed, or else unslaked lime scattered on the floors will aid wonderfully in sweetening the air. A clean factory coupled with sanitary methods of handling will produce a high grade finished product.
In filling tanks, the brine should be tested occasionally with a salometer to check the salting.
As kraut is cut when the weather is cool, the cabbage is cold when it goes into the tanks, and the fermentation will be slow in starting, so that complete fermentation may not result until the following spring.
Very few kraut factories are equipped to heat the fermenting room, and even if they were, the large tanks of cold cabbage would take a very long time for the heat to penetrate to the center and give the proper temperature that is conductive to a healthy and rapid fermentation. Marten claims that from 60 to 65 degrees F. is the most favorable temperature for quality, as he found that high temperatures produce soft and pink kraut. Dr. E. F. LeFevre found the proper temperature for this fermentation is 86 degrees F. and when it falls below this, the activity of the bacteria is decreased. A temperature of about 88 degrees F. may be applied to the shredded cabbage as it enters the carts or tanks. The conveyors may be covered with a galvanized or metal frame for a distance of about 8 to 10 feet from the end, with live steam pipes running along the sides and top of the cover. This, live steam, coming in contact with the cabbage, warms it so that active fermentation will start very quickly, and in some factories the tank of kraut will be completely fermented within one week or ten days. In a rush season when the tanks are in demand, this rapid fermentation is indispensable. Such rapid fermentation will produce quality kraut because there is no opportunity for foreign organisms to get a start. Where the temperature is 75 degrees F. kraut will ferment out in from two to three weeks. Do not turn the steam on full or the cabbage will become scalded, and the great pressure, instead of warming the cabbage, will blow it off the conveyor. Better results are obtained by heating the cabbage than by heating the fermentation room only. If possible, in addition to heating the cabbage, the room should also be heated. Pederson has found that the lower the temperature the slower the rate of fermentation and that when the temperature of the factory is high, the fermentation rate is more rapid, because the cabbage is warmed during the shredding.
The cabbage should be evenly distributed after being salted and packed as solidly as possible. Fill the tank several inches from the top and cover with a layer of clean cabbage leaves, put the cover in place and weight it down with barrels of water or paraffined concrete blocks. Instead of using the cabbage leaves, a canvas or muslin cover can be used. Do not use more weights than are necessary as it is not desirable to have a brine or juice above the cover as it will encourage yeast growth. Usually the day after filling, the cabbage has settled so that the head can be keyed down in the same manner as pickle tanks. While filling with cabbage, it is the practice with some to have the drain plug open and run off the brine until the tank is filled, then close and key the cover down. Others will open the plug at the end of 24 hours in order to settle the cabbage and then key the cover in place. These methods lose brine that may be valuable kraut juice, and also a fine media for the bacterial growth. As the fermentation is lactic, it is advisable to exclude the air as much as possible, in order that the lactic ferment will predominate. Any scum forming on the top of the tank should be removed and not allowed to settle down into the kraut, because yeast will produce an odor and flavor due to its growth. The odor may penetrate into the kraut and produce an undesirable odor. If the kraut is held over in tanks during the summer, it is well to place dry salt around the edge, along the cracks and over the top of the tank. This strong salt acts as a germicide to the bacteria, and also keeps out the air somewhat.
When the tanks are opened, it is necessary to remove the kraut from the top. Active fermentation will start within a few days after filling, and it is well to make daily acidity determinations, the same as in salting pickles, as this is a very good check on the rate of fermentation. As long as the acidity is increasing, active fermentation is continuing and when it ceases, fermentation is either dormant or ended. When the acidity reaches 1.6 per cent it is thought to have reached the proper acidity.
Pederson has found three active bacterial fermentations. The first is due to Leuconistoc mesenteroides which grow best at about 70 degrees F. when 2 to 2% per cent salt has been used. This organism acts on the sugar and produces lactic and acetic acids, alcohol, mannitol and carbon dioxide. The acids and alcohol form esters which produce some aroma. This fermentation ceases when the acidity reaches 0.7 to 1.0 per cent due to the death of this organism. The second fermentation is due to two species—Lactobacillus plantarum and Lactobacillus cucumeris. These also produce lactic acid from the remaining sugar and mannitol. These bacteria are also killed off. The third group which causes fermentation is due to the Leuconistoc mesenteroides which will complete the fermentation. It seems to take the successive fermentation to produce the proper flavored kraut.
Cabbage containing approximately 4 per cent of sugar should produce about 2 per cent lactic acid. Chemical analysis shows that all of the sugar is not converted into lactic acid, some being changed into alcohol, acetic and butyric acids. The results from approximately fifteen samples showed an average salt content of 15 degrees, an acidity of 1.6 per cent and 0.68 per cent of alcohol. A compilation of this data will be the only correct way of arriving at standards. Cabbage can be inoculated with pure cultures of lactic acid of the particular strain that causes the lactic fermentation in cabbage. On account of the great care necessary in growing and handling the pure cultures of lactic acid and the little benefit derived from its use, many prefer not to inoculate, but aid in the development of the natural ferment present on the cabbage when cut. To aid in fermentation, brine from active tanks can be used to inoculate new or inactive ones.
After complete fermentation is over, the kraut can be packed in barrels that have vent holes, so they can be easily rebrined or to allow any gas to pass off should further fermentation set in.
Kraut with an acidity of 1.4 per cent will carry a salt of 14 degrees (3.5 per cent) while a kraut with an acidity of 1.25 per cent will take a 12-degree (3 per cent) salt very nicely. This ratio of salt to acid seems to blend quite well, neither too salty nor too sour. Kraut containing from 2.0 to 2.5 per cent salt seemed to have the best texture. A low salt content will ordinarily produce a kraut that may be too soft to can, whereas too high a content may allow the development of pink yeast.
The following tentative standards have been adopted by the National Kraut Association:
TENTATIVE DEFINITIONS OF POINTS FOR DETERMINING GOOD EDIBLE SAUERKRAUT FOR BOTH BULK AND CANNED
The kraut should have a normal acid flavor, indicative of a properly fermented product. It must never be bitter, sweet or rancid. Brine should show a salometer reading of not more than 20.
The shreds should be uniform in length and thickness as possible and the number of broad pieces of cores must not be excessive.
The color should be light straw or golden; neither white nor dark yellow, and free from black or brown spots.
The kraut should be fairly firm in texture, without being tough. It must never be mushy.
The fill must comply with all the government regulations. The canning kraut and kraut juice will be discussed under the heading of Canning of Vegetables. Canned kraut and kraut juice is to be found under Canning.
TROUBLES:—Yellow kraut may be due to failure to remove sufficient green leaves or as it becomes older it may take on a yellowish tint.
Black or dark kraut may be due to an excessive amount of iron, or to over cooking or again due to contact with the wood of the barrels.
Pink kraut is due to yeast fermentation and may occur when the salt content is rather high.
Off-taste is often prevalent due to contact with kraut that has an offensive odor or taste, or even due to storage in improperly cleaned and paraffined barrels. It should be mentioned that a yeasty or even a butyric fermentation will produce an off-taste.
Due to secondary fermentation of barreled kraut the brine may be forced out of the barrel and if neglected and not rebrined, undesirable organisms may enter and cause soft, mushy, spoiled kraut.