PROBLEMS IN BOTTLING

Otago Daily Times, Issue 22195, 23 February 1934, Page 15

PROBLEMS IN BOTTLING

(Contributed by the Home Science Extension Service.)

1. —Why fruits float in the jar—common occurrence, explain as follows:—(i) Character of the fruit. Some fruits are soft, j tender, and juicy. When heated their in» ! ternal structure breaks down, the fruit (collapses, and as a result tends to float towards the top of the jar. Examples are [Strawberries, soft, juicy plums, (ii) Im- ! proper packing: If the jars are not proj perly packed—that is, if not enough fruit is packed into the jar—the tendency is for loosely-packed fruit to float in the syrup. This is a natural result since the specific gravity of the fruit is less even than water. (Hi) Over processing: Fruits that are much over-proces9ed become soft and flat for the same reasons as given under (i). (iv) Syrup too heavy: If the syrup is too heavy it will cause shrivelling of the fruit and a consequent floating. Bottling syrups should be adapted to the acidity of the fruits and rarely will require heavier than 50 per cent, to 60 per cent, sugar. 2. Lack of Liquid in the Jars.—This is one of the most common troubles when bottling in glass jars. Futhermore it occurs m bottling almost all foods where a free liquid is part of the jar's contents, borne of the common causes:—-(1) Improper packing: If the materials are packed too lightly in the neck of the jar tne gases and steam do not escape readily, consequently pressure is set up within the jar. When the pressure becomes sufficiently great to force an opening through the tightly-packed neck, a portion of the liquid content is carried out with the escaping gases and steam. (2) Air pockets left in the jar: When the liquid is poured in over the solids large pockets of air are likely to be imprisoned among the pieces of solid. These escape during processing, and the liquid level sinks because these spaces are now filled with the liquid. The difficulty may be overcome by: (a) Using hot liquids. The heat expands the air, which bubbles out. After standing a few minutes more liquid is added to give a proper fill, (b) Agitation of the jar after pouring in the liquid will generally cause the air to become dislodged. The jar may be grasped around the neck and rotated quickly to right and back again - few times, (e) A thin flexible spatula may be run down the side of the. jar, and by pressing outward on the handle the blade will press in upsetting the equilibrium of the air bubbles. (3) Insufficient blanching: In some cases —e.g., string beans, asparagus, sliced apples, etc. blanching is primarily given for the purpose of expelling included gases. If this is not done the gases are expelled during processing. Then after removal of the jars from the processor much of the liquid is absorbed by the solids _ leaving the free liquor at a low level in the jar. In blanching and cooling such products the operator should endeavour to leave materials in the blanching water as long as safety will permit, and in cooling they should be left in the cold water long enough to ensure absorption of water to fill spaces formerly occupied by the gases. Well blanched and properly cooled materials will sink rather than float in cold water. (4) Jars too tightly sealed: In all common types of jars used in home bottling provision is made for _ the jar to be only partially sealed during processing. Pressure is necessary to lift the cover sufficiently to allow for escape of gases; but if considerable pressure is necessary to lift the cover the pressure is uniformly distributed throughout the jar, and when it becomes suffici* ently great to lift the cover the outrushing gases carry some of the liquid with them. (5) Improper manipulation of the processor: When processing in the water bath it is desirable that the tops of the jars be covered with water throughout the processing period, or failing this, the processor should be equipped with a cover which should be taken off just before the fire is removed from under the processor. When processing under steam pressure, the pressure should be maintained uniformly throughout the processing period. The pet cock must nob be opened till the pressure inside the processor has fallen to zero. When processing is taking place in the steamer, the doors of the steamer must be opened before the fire is removed. Otherwise a vacuum may form within the steamer causing the liquid to flow out from the jars. This same condition is likely to obtain in the case of the covered water bath, if the water doeß not cover the tops of the jars, because under these conditions the water bath actually becomes a steamer, and should be manipulated as such.

3. Spoilage of Bottled Foods.—(l) ImI perfect containers—cracks, imperfectlyfitting covers, the jar does not seal airtight after processing, and food spoils. Careful inspection of the jars before packing will eliminate, a large amount of this trouble. (2) Poor sealing medium —jars must be sealed airtight' if the food is to keep. Rubber rin/rs should be carefully tested. If hard and brittle or broken, in places discard them. .Each season use a supply of new rings. (3). Over-packed jars. All processing periods j are based on moderately-packed ers. If those materials tend to form a tight pack with little or no. "free liquid present, they are over-packed, and the normal processing period is insufficient to preserve them. The worker- had better err on the side of underpacking and have palatable products rather than to over-pack-and, have spoiled foods. (4) Underprocessing. There are so many ways in which the housewife may underrprocess and still feel that the proper time has been given—e.g., (a) begin counting time too soon, (b) temperature below proper degree for' a part of the period, (c) water allowed to boil off, exposing tops of jars, (d) slightly over-packing, (e) water boiling below 212 deg F. Too much emphasis cannot be placed upon care in processing. " The housewife would gain far better results if she extended the period of vegetables, meats, and poultry beyond the normal period rather than make any reduction. (5) Improper manipulation of any materials. Many of the flat, 60ur results no doubt arise from allowing blanched materials to stand around too long before processing. The bacteria which are responsible for this trouble thrive best at temperatures of lOOdeg150deg Fahrenheit. Prepared material, then, should be kept cool till it can be processed. If prepared materials are packed and covered with hot liquid they should go into the processor within the hour. .(6) Storage: Bottled foods should

be stored in a cool and dry place. Warm storage hastens deterioration and spoilage. 4. Discolouring of Fruit.—Sometimes the fruit on. top of a jar turns brown or black after the jar has stood for some time. This is due to enzyme activity, and indicates under-processing. Either the processing period waa not long enough to exhaust the air properly or the temperature of the fruit was not sufficiently high to render the enzymes inactive. This is most likely to occur with large fruits such as pears, plums, and peaches. The remedy is an increase of a few minutes (5-10) in the processing period.