Q. Why does honey turn granular? Does this mean that the honey has spoiled? If it has not spoiled, how does one make grainy honey smooth again?
A. Honey is a syrupy solution of the following: 17 percent water, 38 percent fructose (fruit sugar), 30 to 34 percent glucose (blood sugar or dextrose), 1 to 5 percent sucrose (table sugar), 8 percent other sugars, 0.6 percent floral acids, 0.3 percent proteins and 0.2 percent minerals. These concentrations vary with season and flower.
Normally, honey keeps well at room temperature. Neither bacteria nor molds are able to survive under such parched conditions. Some yeasts, however, which have established an ecological niche among the bees, can survive and grow in honey. These cause raw (unproceessed) honey to foam and cloud, especially during the summer months. They are quite harmless and are easily destroyed through pasteurization.
Honey's occasional granularity has nothing to do with spoilage, however. Instead, the granules are actually glucose crystals. With so little water in which to be dissolved, the least soluble of the sugars crystallizes out first.
There are three factors related to glucose crystallization:
*Plant type. Honey very often is produced from the nectar of only one or two flowers, since every plant flowers at a different time and bees have a limited area of operation. Therefore, honey can be separated and classified by the predominant plant from which the nectar was extracted. Honeys made from nectars that are mostly sucrose are almost equal in fructose and glucose contents. These crystallize reluctantly, as do honeys with a predominance of fructose. But those honeys with a relatively high concentration of glucose -- clover, for example -- crystallize easily.
*Temperature. Honey crystallizes most in the winter, especially now that we are all turning our thermostats lower during the coldest winter nights to save fuel. Glucose is less soluble in cool honey and therefore even more likely to crystallize.
*Processing. Processed honey is less likely to crystallize than raw honey, because one of the steps during processing is a mild pasteurization, followed by filtering. Pasteurization dissolves minute, invisible glucose "seed" crystals, and filtering removes any that did not dissolve. A seed crystal is any crystal that serves as site for further crystallization.
One might think that the water in honey evaporates during storage and causes crystallization, much as the evaporation of water from a candy syrup causes crystallization. This is not possible with honey, because it is not being heated and because its high sugar concentration binds the water and prevents any molecules from escaping. Hence, honey left out uncovered even in a dry climate would neither diminish in volume nor crystallize if it had been processed.
To recoup one's granulated investment, place the honey jar or pot in a pan of hot water. The glucose crystals will quickly dissolve.
Q. What microbial dangers might lurk within a seviche prepared with raw bay or sea scallops? What about other fish or molluscs?
A. Assuming that the fish or mollusc is not contaminated to begin with (a pretty safe assumption if it is fresh and not smelly), there should be no danger of food poisoning provided one refrigerates any leftovers. Seviche (a fish or mollusc salad) has a very poor, watery texture if consumed after more than a couple of hours, anyway.
Seviche is prepared by mixing raw fish or scallops with lime juice, garlic, olive oil and chopped, fresh coriander. The lime juice gives the fish or mollusc flesh a "cooked" texture. It does this by lowering the meat's pH below 5, at which point the muscle proteins lose their abilities to bind water. If one adds too little lime juice, the fish doesn't "cook" and the salad has an unpleasant, gelatinous texture. If, on the other hand, one adds too much lime juice or serves day-old seviche, the fish pieces have the texture of cotton and the salad itself is a pool of liquid.
A well-made seviche is acidic enough to at least prevent bacterial growth, if not to kill off the populations already present. Bacteria cannot thrive under these conditions. Those present on the fish (fresh fish has a bacterial load between 10,000 and 100,000 cells per gram) probably perish during the half hour that the fish marinates. Molluscs add few bacteria, since they are alive (although their shells are certainly not sterile). Again, the lime juice would have an antiseptic effect.
For answers to your cooking and food-related questions, write to Tom Neuhaus, The Washington Post, 1150 15th St. NW, Washington D.C. 20071.