The Kosher Kitchen - Planning the Kitchen
While a kitchen remodeled or designed for kashrut observance with two sinks, two stoves, and separate working areas is certainly a great convenience, it is by no means a necessity.
"Dairy" and "Meat": In keeping with the total separation of meat and dairy required in the kosher kitchen, separate sets of dishes, pots, silverware, serving dishes, bread trays and salt shakers are needed. These different sets should be kept in separate cabinets. Also necessary are separate sets of draining boards, draining racks, dish sponges, scouring pads, dish towels, and tablecloths. Dish soap, cleanser, and scouring pads used for dishes and pots must have a Hechsher (kashrut certification). A very practical and widespread practice in Jewish homes is to plan the different sets of meat and dairy utensils around a color scheme. A traditional example is red for fleishig (meat) and blue for milchig (dairy). Draining racks, sponges and dish towers are key elements in this color system. Choose your own color scheme and use it as a reminder for yourself and anyone else who will be working in your kitchen. (The dishes themselves need not conform to a strict color scheme, but should be readily distinguishable.)
One must be especially careful to mark utensils that look similar for both meat and dairy, such as knives, ladles or wooden spoons. Distinguish between such utensils by having a different color or design, or paint a line on the handles according to the color scheme. Plastic tape, color-coordinated signs, or paint of the same color may be used to mark items.
The separation of meat and dairy must be maintained throughout the kitchen. Consult you Rabbi as how to clean and kasher surfaces or appliances that were non-kosher.
Separate sinks for washing dishes and preparing foods are recommended. If the two sinks are adjoining, there should be an effective separation between them so that no water or food splashes from one sink to the other.
If there is only one sink, it may be used after it has been completely cleaned, but the inside of the sink should be regarded as non-kosher. No food or dishes should be put directly into non-kosher sinks. There should be separate dish pans and slightly elevated racks under the dish pans for both meat and dairy. Similarly, two sinks which were used before the kitchen was kosher should also be regarded as non-kosher, unless they are stainless steel and were koshered. If the two sinks were koshered, one should be designated for meat and one for dairy.
A table can be used at different times for meat and dairy if one uses different tablecloths or placemats. A new table or a table surface that was koshered can be used for one category and a tablecloth or placemats used for the other.
Designate separate countertops or work areas for meat and dairy. If one area must be used for both, separate coverings must be used.
Refrigerators and Freezers:
These may be used for all food types. However, separate areas should be designated for meat and dairy foods. Sometimes a shelf or the door of the refrigerator or freezer is kept for dairy. If dairy is kept on a shelf inside the refrigerator, one should cover the shelf with aluminum foil or a plastic liner to prevent leakage onto other foods. If dairy drips on the foil, the foil must be carefully removed and replaced. Similar care must be taken with meat products inside the refrigerator.
One should avoid placing hot meat or hot dairy foods in the refrigerator as this may affect the other foods in the refrigerator and cause kashrut problems.
The stove top:
Where heat is involved, the laws concerning the accidental mixture of meat and dairy foods become much more complex. Therefore, strict precautions are taken concerning the use of the stove and oven for meat and dairy products.
The ideal set-up in the kosher kitchen is to have two separate stoves. A practical alternative is to use the full size range for meat, and a portable gas or electric range or cook top for dairy. Where one stove is used, separate burners designated for milk or meat use are preferable. If this is not possible, extra care must be taken to keep the burners very clean.
It is best to avoid cooking both types of food at the same time since the steam or food in one pot might splatter or escape to another, creating serious kashrut problems regarding the food and pots involved.
If it becomes necessary to cook both meat and dairy foods in separate pots at the same time, utmost care should be taken that the lids are secured tightly at all times and that an upright sheet of tin or other metal separates the pots. Be careful to avoid lifting lids of both meat and dairy pots at the same time. If the lids must be lifted to check the food or add any ingredients, raise the lid only slightly off the pots, tilted away from the opposite pots. It is best to have the meat and dairy pots well separated, to keep the steam or liquid from coming in contact with each other.
The Oven and Broiler:
It is best to use the oven for only one type of food: meat, pareve or dairy. If only one oven is available, the use of portable broilers or toaster-ovens for other food types is advisable. Meat and dairy foods can never be baked or broiled in one oven at the same time, even in separate bake ware.
If you wish to keep the oven pareve, then meat or dairy foods cooked in that oven (at separate times) must be tightly covered all around, including the bottom. It is advisable to place a piece of foil under the pan and to change it for meat or dairy use. The pan may be opened for testing only when it is completely removed from the oven.
Dairy foods should not be baked in a meat oven, and vice versa. Pareve foods baked in a meat oven (or broiler) should not be served on dairy dishes or eaten with dairy foods, unless the following conditions are met:
*The oven, racks, and broiler are thoroughly clean. (It is helpful to put a piece of foil under the bake ware to ensure the cleanliness of the oven racks.) This might be difficult to achieve without a self-cleaning oven.
*24 hours have elapsed since the oven was used for meat. For example, if meat is baked in the oven, and then you wish to bake a cake which can be served with milk, first be sure the oven and racks are clean, and then wait 24 hours before baking the cake. The same conditions apply if one wishes to bake pareve in a dairy oven. It is advisable to have separate bake ware for pareve.
If the oven is clean, the waiting periods between milk and meat is not required for pareve foods baked in a meat or dairy oven.
To use an oven for both meat and dairy at separate times, consult an Orthodox Rabbi.
All of the above also applies to broilers which are on the bottom of the oven. Regarding the use of self-cleaning and microwave ovens, consult and Orthodox Rabbi.
Portable Electric Broilers:
These must be used for either meat or dairy exclusively because they cannot be properly koshered.
An electric mixer, blender or grinder does not require a separate motor in order to be used for meat and dairy. However, one must buy separate attachments if the appliance is to be used for more than one food type (meat, dairy, or pareve). Even when using separate attachments, the machine should be cleaned well on all sides after each use.
These should preferable be designated for the exclusive use of either meat or dairy. If you have further questions, consult an Orthodox Rabbi, as there are many factors involved.