Safety Rules for Refrigerated Food

Question: During the summer we cruise about on our small sailboat. I am the cook and the crew. Once we leave the electricity behind, the refrigerator keeps beer chilled for four days. That’s fine for beer.

My question is, what is the minimum safe temperature to keep opened canned ham, mayonnaise, salad dressing and other products marked “keep refrigerated?” I use a lot of canned products. How safe, under the same conditions, are canned mushrooms, fruit, vegetables and soup leftovers? Are these items safer stored in a jar or plastic rather than left in the can?

Answer: The universal safety rule is to keep foods in the refrigerator at a temperature of 40 degrees or lower (down to 34 degrees). Above this temperature foods spoil rapidly as both infectious bacteria and toxin-producing microorganisms start to grow. Check the temperature with an accurate refrigerator thermometer or outdoor thermometer. Another important thing to remember is that all leftovers should immediately be stored in the refrigerator.

Canned leftovers may be safely left in the can, tightly covered and stored in the refrigerator for a few days. However, to prevent any metallic flavors, odor and darkening in the foods caused by oxidation and metal reaction, they may be transferred to a sealed jar or plastic container.

Here’s a guideline on how long to keep canned foods in the refrigerator after opening:

Baby food: 2 to 3 days

Fish and seafood: 1 day

Fruit: 1 week

Gravy, broths: 2 days

Meats: 2 days

Pickles, olives: 1 to 2 months

Poultry: 1 day

Sauce, tomato based: 5 days

Vegetables: 3 days

Mayonnaise, salad dressings, catsup, relishes: 2 to 3 months

Q: Is there any trick to removing two glasses stuck together? I often find this a problem as I stack glasses in my small and crowded kitchen cupboards.

A: Yes, separation may be accomplished by the use of hot and cold water. Pour cold water or ice into the inner glass. Immediately immerse the outside of the outer glass in hot but not boiling water and then pull the glasses apart. The cold water will contract the inner glass and the hot water will cause the outer glass to expand.

Q: Recipes often say, “Soften unflavored gelatin in cold water;” what exactly is the reason for this? Another recipe also instructs to mix the gelatin with sugar and doesn’t require the cold water treatment. Can you please enlighten a confused cook?

A: When unflavored gelatin is stirred with a little cold water, the crystals become wet and expand, trapping in water molecules. When the cold water is used first, the gelatin readily accepts the hot water that is then added. If mixed with the hot water in the dry stage, the granules will lump and not dissolve. And when lumpy, the gelatin will not disperse throughout the food to be gelled and thus will not set.

Equal portions or more of sugar blended with the dry unflavored gelatin crystals will counteract the gelatin’s tendency to clot and become lumpy. That’s why directions on the packaged fruit-flavored gelatins with a high sugar content can drop the cold water step and simply say to dissolve the gelatin-sugar mixture in hot water.

Address questions on food preparation to You Asked About, Food Section, The Times, Times Mirror Square, Los Angeles 90053. Personal replies cannot be given.