- The Washington Times - Saturday, August 13, 2005


By Robert L. Wolke

W. W. Norton & Co., $25.95, 384 pages


It is very unlikely that Albert Einstein, if he in fact had a cook, would have told him or her anything contained in Robert L. Wolke’s new book. Once the reader gets beyond the title, however, he will find a wonderful source of useful and fascinating information about the chemistry of foodstuffs and cooking. Mr. Wolke is professor emeritus of chemistry at the University of Pittsburgh, and his earlier popular books have dispensed a blend of appealing writing and authoritative chemistry good enough to have won him the American Chemical Society’s 2005 Award for Interpreting Chemistry for the Public. This volume continues that admirable tradition.

Mr. Wolke writes a food column for a Washington newspaper, and the book is arranged in a question-and-answer format, where most of the questions were submitted to him by readers of his column. Mr. Wolke answers the questions with a clear account of the scientific facts and principles involved, adding more technical details in numerous sidebars. He further enlivens the book with a selection of food-based puns, taken from what he calls his “fictionary,” and complements the discussion with a set of recipes provided by his wife, the restaurant critic and food writer Maxine Parrish.

The chapters are organized by the categories of food they discuss, starting with beverages, and moving on through dairy and eggs, vegetables, fruits, grains and carbohydrates, seafoods, meats and herbs and spices, with a chapter on kitchen equipment and a concluding miscellany of information that did not quite fit in elsewhere.

In his chapter on beverages, Mr. Wolke explains why refrigerated tea turns cloudy, elucidates the differences involved in brewing black tea, green tea and coffee, explains why the tea (or coffee) will keep hotter longer if the milk (or cream) is added first, and why champagne keeps its fizz longer than beer or soda. He also provides some helpful hints on removing wine stains. Moving on to dairy foods, he clarifies the differences between different types of cream, pens a paean to butter (“calling butter a fat is like calling the Queen Mary a transatlantic ferry”) and explains what gives soft ice cream its texture (it is kept at a higher temperature than hard ice cream.)

To a reader upset that skim milk has been replaced by fat-free milk, which has an inferior taste, he considerately breaks the news that only the name has changed, and expresses gentle skepticism that yogurts containing live culture are superior to those where the bacteria have been killed. He explains why brown and white eggs do not differ in any way other than shell color, tells the reader where to find restaurants that specialize in double-yolk eggs, and provides hints on preventing slightly cracked eggs from losing their whites as they cook (add salt or vinegar to the water) and how to make cooked egg yolks turn green (cook them at a below-boiling temperature.)

Mr. Wolke discusses the chemical compounds responsible for vegetables’ distinctive colors, and why you should cook veggies quickly if you want their colors to remain bright and attractive. He expresses skepticism about the value of products sold for washing fruits and vegetables, suggesting that dirt can be washed out effectively by running water and that bacterial contamination can be tackled with a little dishwashing detergent, or by a two-stage wash with hydrogen peroxide and white vinegar, typically pointing out that this also helps provide a salad dressing. He reveals that spinach does not contain a large amount of iron, a mistaken belief that originated in a paper by German nutritionists a century ago that contained a misplaced a decimal point and was widely propagated by Popeye cartoons before it was noticed and corrected in the 1940s.

Mr. Wolke also tells us how to avoid tears while cutting onions (refrigerate them first and/or cut them quickly), and provides a very helpful dissertation on ripening fruit. Introducing a word that may be new to most readers, he explains that some fruits, known as climacteric, continue to ripen after picking, while others, which are not surprisingly called nonclimacteric, will never get any riper than they were when they left the tree. He provides lists of each kind of fruit. Fortunately for people who enjoy sweet fruit, there are more of the former among the fruits we commonly eat, and they can be ripened by placing inside a paper (not plastic) bag so that the ethylene gas naturally given off by the fruit can do its ripening task effectively. If you want ripe fruit in a hurry, also put an apple or banana in the bag, and the large quantity of ethylene they emit will do the job very effectively.

The book also provides an extensive discussion of fats and oils, including the differences between different grades of olive oil and the differences in molecular structure between saturated, unsaturated and trans fatty acids. Among the other diverse topics covered are an explanation of why farm-raised salmon is not red like the wild variety (different diets), the ineffectiveness of vacuum devices that claim to marinate meat more effectively, the best way to deodorize a refrigerator (keep it clean) and the best way to roast marshmallows. In short, the book is a veritable cornucopia of gastronomical information as enjoyable to the brain as good food is to the stomach.

Jeffrey Marsh has written widely on scientific topics and public issues ranging from nuclear strategy to social policy.

Sign up for Daily Newsletters

Manage Newsletters

Copyright © 2019 The Washington Times, LLC. Click here for reprint permission.

Please read our comment policy before commenting.


Click to Read More and View Comments

Click to Hide