In hot-pack canning, the food is heated first and placed hot into jars; in cold-pack canning, raw food is put into jars and hot liquid is poured over it. The difference is not just practical; processing times differ too: the two methods have separate tables, and one cannot be processed using the other’s time. Read the processing time from the table for the method specified by the recipe; do not confuse the two.
There are two names for how a jar is filled for canning. With hot-pack, the food is heated in a pot first, brought briefly to a boil, and placed hot into a hot jar; its own hot water or brine is added on top. With cold-pack, raw food is packed tightly into the jar and only hot liquid is poured over it. Both are valid methods, but they are not the same method, and recipes clearly state which one they use. Follow the method specified by the recipe; do not combine the two methods in the same jar.
The difference comes from the temperature of the food when it goes into the jar. With hot-pack, the jar starts processing warm, so it takes less time for heat to reach the center. With cold-pack, the center is cold; it takes longer for heat to reach it, and the processing-time table is calculated separately to account for that. That is why a recipe’s processing time cannot be separated from the packing method. Using a time written for hot-packed food on a cold-packed jar means the process is incomplete. Extending the time by guesswork is not a solution either, because the table has not been tested for that condition.
Hot-pack has another benefit. The heated food shrinks somewhat and releases air; as a result, the jar stays fuller, fewer pieces float to the top, and less air remains inside the jar. Less air means less color loss on the shelf and a better vacuum seal. With cold-pack, the food shrinks during processing, leaving more headspace than expected; the contents may rise above the liquid and darken there.
The choice depends on the texture of the food. Cold-pack may be preferred for firm foods that hold their shape without crushing, because the pieces stay whole. Hot-pack gives better results with soft foods and legumes. But this is first a question of suitability, not taste: not every food has a tested processing time for both methods. If a recipe specifies only one method, the other method is considered untested for that food and should not be used. If you want to try a new food, first look for a published recipe for that food.
The packing method does not change the canning method itself. Hot-pack does not make a low-acid vegetable suitable for a boiling-water bath; even if the food has been heated, there is no recommended boiling-water canning method for a non-pickled vegetable. Hot-pack only determines which table to use for the processing time in a pressure canner. Leave the headspace specified by the recipe when filling the jar, and wipe the rim; a greasy or food-covered rim directly prevents a vacuum seal. Wipe the rim with a damp cloth and rinse the cloth after each jar.
A Note for Readers
This content is for informational purposes only and is not a substitute for medical advice. Consult your doctor before making any decision about your health.
Comments (4)
Sıcak dolumun kavanoza daha çok ürün sığdırması da bir kazanç, aynı kavanoza belirgin biçimde fazla giriyor.
Soğuk dolumda kavanozda sonradan boşluk kalıyor bende, sebze çekiyor herhâlde.
Ben hep çiğ doldurup üstüne kaynar su ekliyordum; yani soğuk dolum yapıyormuşum ama tarifi sıcak doluma göre yazılmış bir kaynaktan alıyordum. Kavanozlarımın bazılarının neden vakum tutmadığı belki de bundandır.
Sıcak dolumda kavanozun işleme ılık başlaması süreyi de değiştiriyor mu?
Süreyi tarif belirliyor ve tarifler zaten yönteme göre yazılıyor; sıcak dolum için verilen süre soğuk dolumdan kısa oluyor. İki yöntemin süresini birbirinin yerine kullanmak en sık yapılan hata.