This is Improbable

by Marc Abrahams

  Yukiko and Ikuo conducted taste tests with sixteen healthy female humans, sixteen healthy female rats, and fourteen different brands (nine Japanese, two Belgian, and two French) of bottled water. The water, all of it, was uncarbonated. For good measure, the taste testers also taste-tested tap water.

  The women drank from cups, the rats from objects called ‘drinking tubes’. The report specifies that the rats each weighed 160 grams, give or take three grams, and were ‘housed individually’. We are told nothing, not a blessed iota of fact, about the weight of the women, or about their living arrangements. The report also specifies that ‘Before beginning the experiment, each animal was fed on a commercial stock diet’, but says nothing about what the women consumed.

  Yukiko and Ikuo reached two main conclusions. First, they write, ‘appropriate levels of minerals are needed for tasty drinking water, too little being as bad as too much, with around 58.3 milligrams/liter of hardness being most favorable’. Second, and perhaps more memorably: ‘The present study has demonstrated that the preference for different types of natural mineral water by female college students was similar to that by rats.’

  Yukiko and Ikuo make no claim that theirs is the final word. For one thing, they point out, ‘The menstrual cycle of the subjects was not considered in this experiment, although taste sensitivity can be influenced by it.’

  ‘Similar Preference for Natural Mineral Water between Female College Students and Rats’ is not the only research study to proudly, explicity comparison-test college students and rats. But it may be the most exuberant since C. Lathan and P. E. Fields’s 1936 tell-all ‘A Report on the Test-retest Performances of 38 College Students and 27 White Rats on the Identical 25 Choice Elevated Maze’.

  Yukiko, Esumi, and Ohara Ikuo (1999). ‘Similar Preference for Natural Mineral Water between Female College Students and Rats.’ Journal of Home Economics of Japan 50 (12): 1217–22.

  Lathan, C., and P. E. Fields (1936). ‘A Report on the Test-retest Performances of 38 College Students and 27 White Rats on the Identical 25 Choice Elevated Maze.’ Journal of Genetic Psychology 49: 283–96.

  Eggs Allsorts, Birdflesh Everykind

  Which birds are the most edible, and which are the least? During and just after World War II, Hugh B. Cott of the University of Cambridge doggedly pursued these questions, using means that were waspy, feline, and human. His discoveries are summed up in a 154-page report entitled ‘The Edibility of Birds – Illustrated by 5 Years Experiments and Observations (1941–1946) on the Food Preferences of the Hornet, Cat and Man’.

  In October 1941, Cott made a chance observation. While collecting and preserving bird skins in Beni Suef, Egypt, he discarded the meaty parts of a palm dove (Streptopelia senegalensis aegyptiaca) and a pied kingfisher (Ceryle rudis rudis). Hornets descended upon the palm dove carcass, but ignored the kingfisher.

  Cott, entranced, later offered other hornets a choice of different cuts (breast, wings, legs, and gut) of some forty different bird meats, in 141 experiments conducted in Beni Suef, Cairo, and Tripoli, Lebanon.

  The hornets especially took to crested lark, greenfinch, white-vented bulbul, and house sparrow. They voted (metaphorically) thumbs down on golden oriole, hooded chat, masked shrike, and hoopoe, among others.

  Cott conducted another forty-eight experiments, with nineteen kinds of bird meat, using three cats (two in Cairo, one in Tripoli) as tasters. In each experiment, the taster chose (or chose not to choose) between two different bird meats.

  To answer the ‘which would a human eat’ question, Cott gathered data ‘from natives in the Lebanon; from personal experience and from observations sent in reply to a published inquiry; and from the [scientific] literature’. He drew most heavily from Reverend H. A. Macpherson’s occasionally mouthwatering 1897 tome A History of Fowling.

  Surveying the results of all those taste tests of all those birds by hornets, cats, and people, Cott saw both rhyme and reason. He concluded that, in most cases, humans and cats ‘agreed with the hornets in rating more conspicuous species as relatively distasteful when compared with more cryptic species ... Birds which are relatively vulnerable and conspicuous ... appear in general to be more or less highly distasteful – to a degree likely to serve as a deterrent to most predators.’

  At the other extreme, birds that have especially inconspicuous or camouflaged appearance, Cott almost cackles, ‘are also those which are especially prized for the excellence of their flesh’. The list of these includes the Eurasian woodcock, skylark, and the mallard duck.

  Among the widely disliked were kingfishers, puffins, and bullfinches. Cott cautioned his readers that ‘palatability may change with growth and age of the bird; and it differs markedly in different parts of the same individual’.

  But as with the special case of chickens and eggs, this is neither the beginning of the story nor its end. At roughly the same time, Cott was also running an extensive programme to test the palatability of every kind of bird egg he could find. The titles of his studies are pretty self-explanatory:

  The Palatability of the Eggs of Birds – Illustrated by Experiments on the Food Preferences of the Hedgehog (Erinaceus europaeus)

  The Palatability of the Eggs of Birds: Illustrated by Three Seasons’ Experiments (1947, 1948 and 1950) on the Food Preferences of the Rat (Rattus norvegicus)

  The Palatability of the Eggs of Birds – Illustrated by Experiments on the Food Preferences of the Ferret (Putorius furo) and Cat (Felis catus) – with Notes on Other Egg-Eating Carnivora’ (Those other carnivora are numerous, and include civets, mongooses and meerkats, hyenas, dogs and dingoes, otters, aardwolves, and foxes.)

  Cott’s research programme could (although was not, so far as I know) be summarized as ‘Go suck eggs!’

  Egg palatability experiments are potentially of great practical value. Island nations, Britain pre-eminently, were and are vulnerable to enemies who would block food shipments from overseas. One could counter the danger by discovering unknown or unappreciated edible native foodstuffs. A simple way to begin: collect bird eggs and test their palatability.

  Egg collecting, like other research activities, is not without hazards. Cott relates an incident that’s documented in an 1882 monograph: ‘The victim, having collected a basket-full of the first eggs of the season, and wishing to procure more, had sent his wife to empty the basket in the village. In her absence, he fixed his rope to the cliff-top and made a second descent. Meanwhile a fox ran up, and gnawed the rope till it severed, at the place where the man had previously rubbed his yolk-smeared hands.’

  Cott’s experiments mainly addressed a scientific question – demonstrating that, usually, the most conspicuous eggs taste terrible to whatever might want to eat them.

  Cott also used human egg taste-testers. In 1946, he entered a six-year collaboration with the Cambridge Egg Panel, one of many similar bodies formed during World War II to help regulate the nation’s food supply. Under Cott’s direction, panellists tasted the eggs of 212 bird species. This resulted in a 129-page report called ‘The Palatability of Eggs and Birds: Mainly Based upon Observations of an Egg Panel’. It has raw data, supplemented with colourful highlights from the tasters’ own notes and from other sources, including Cott’s coterie of egg-collecting correspondents.

  For the egg panellists, ‘samples were tested in the form of a scramble, prepared over a steam-bath, without any addition of fat or condiment’. Each taster assessed each sample on a scale dropping from ‘ideal’ way down to ‘repulsive and inedible’.

  The paper concludes with a list of the different egg types ‘in descending order of acceptability’. Keep in mind that these are the aggregate preferences; individual tastes may vary. Most acceptable: chicken, then emu and coot, then black-backed gull. The eggs of last resort, as rated by official British egg-tasting persons: green woodpecker, Verreaux’s eagle owl, wren, speckled mousebird, and, dead last, black tit.

  Cott’s work proved to be, among other things, inspirational. A gen
eration later, Richard Wassersug (see page 173) cited it as both inspiration and, to some extent, guide for his research into the palatability of Costa Rican tadpoles.

  Cott, Hugh B. (1945). ‘The Edibility of Birds.’ Nature 156 (3973): 736–37.

  –– (1947). ‘The Edibility of Birds – Illustrated by 5 Years Experiments and Observations (1941–1946) on the Food Preferences of the Hornet, Cat and Man – and Considered with Special Reference to the Theories of Adaptive Coloration.’ Proceedings of the Zoological Society of London 116 (3-4): 371–524.

  –– (1948). ‘Edibility of the Eggs of Birds.’ Nature 161 (4079): 8–11.

  –– (1951). ‘The Palatability of the Eggs of Birds - Illustrated by Experiments on the Food Preferences of the Hedgehog (erinaceus-europaeus).’ Proceedings of the Zoological Society of London 121 (1): 1–40.

  –– (1952). ‘The Palatability of the Eggs of Birds: Illustrated by Three Seasons’ Experiments (1947, 1948 and 1950) on the Food Preferences of the Rat (Rattus norvegicus); and with Special Reference to the Protective Adaptations of Eggs Considered in Relation to Vulnerability.’ Proceedings of the Zoological Society of London 122 (1): 1–54.

  –– (1953). ‘The Palatability of the Eggs of Birds – Illustrated by Experiments on the Food Preferences of the Ferret (Putorius-Furo) and Cat (Felis-Catus) – With Notes on Other Egg-Eating Carnivora.’ Proceedings of the Zoological Society of London 123 (1): 123–41.

  –– (1954). ‘The Palatability of Eggs and Birds: Mainly Based upon Observations of an Egg Panel.’ Proceedings of the Zoological Society of London 124 (2): 335–463.

  A Beef Boom

  Before John Long applied his expertise to the problem, people tried many ways to make meat more tender – chewing it, pounding it, soaking it in enzymes.

  The report, ‘Hydrodyne Exploding Meat Tenderness’, published in 1998 by the US Department of Agriculture (USDA), describes Long’s act of creation as ‘a peacetime use for explosives’. It goes on: ‘Throughout John Long’s career as a mechanical engineer, he worked with explosives at Lawrence Livermore [National Laboratory]. His mission: preparing the Nation’s defense. He always wondered if the explosives he studied could be used for peaceful ends – like tenderizing meat. Then, after more than 10 years of retirement and long after the Cold War’s end, he began pursuing the Hydrodyne concept in earnest.’

  The article explains that in 1992, Long teamed up with a meat scientist, Morse Solomon. Their first set-up was ‘an ordinary plastic drum filled with water and fitted with a steel plate at the bottom to reflect shock waves from an explosion’. By 1998, Long and Solomon were stuffing meat, water, and explosives into a seven-thousand-pound (3180-kilogram) steel tank covered with an eight-foot (2.4-metre) steel dome.

  This official USDA story of how it all began looks past the fact that another man, Charles Godfrey of Berkeley, California, obtained a patent in 1970 for his ‘apparatus for tenderizing food’. Godfrey’s first sentence blasts away all confusion: ‘An article of food is tenderized by placing it in water and detonating an explosive charge in the vicinity thereof.’

  Godfrey explains his method: ‘A cut of meat desired to be tenderized is placed under water within a tank. In view of the tendency of the meat to float, it may be necessary to tie the meat in position by a string ... A compressive pressure wave traveling at a speed higher than the velocity of sound may be generated in the water by a means, such as a charge of high explosive, which is supported above the meat by any suitable means, such as the leads which are used to ignite the detonator of the high explosive.’

  Once the idea was out there, other scientists took to experimenting with beef, pork, chicken, and other things that went boom. A study in 2006 alluded to a scientist named Schilling who showed that ‘the hydrodynamic shock wave ... did not affect the color of cooked broiler breast meat’.

  How to generate a shock pressure wave for tenderizing an article of food. Detail from US Patent no. 3,492,688

  A pamphlet from the National Cattlemen’s Beef Association bragged that ‘technology has been shown to improve the tenderness of beef by 30-80% and, the tougher the piece of meat, the greater the magnitude of improvement’. But so far the process works well only for small, sub-industrial quantities. The niggling problem, when applying explosives to heaps of flesh, is how to tenderize without pulverizing.

  Lee, Jill (1998). ‘Hydrodyne Exploding Meat Tenderness.’ Agricultural Research (June): 8–10.

  Godfrey, Charles S. (1970). ‘Apparatus for Tenderizing Food.’ US Patent no. 3,492,688, 3 February.

  Pet Palates

  Pet food taste-testing by humans rose to a new level of formality with the publication of the scholarly study ‘Optimizing the Sensory Characteristics and Acceptance of Canned Cat Food: Use of a Human Taste Panel’. The author, G. J. Pickering of Brock University in St Catharines, Ontario, Canada, reports: ‘Cats are sensitive to flavour differences in diet, very discriminative in food selection, and clearly unable to verbalize their likes and dislikes. These issues have dogged the industry for decades.’

  Pickering explains that taste tests with volunteer cats suffer three drawbacks. They are ‘expensive to maintain, time consuming, and yield limited and often equivocal data’. So he offers an alternative: ‘In-house tasting trials using a human taster are commonly conducted by the pet food industry, although there is a paucity of relevant information in the scientific literature.’

  His study serves up a hearty helping of information. Human volunteers rated thirteen different commercial pet food samples, concentrating on eighteen so-called flavour attributes: sweet, sour/acid, tuna, herbal, spicy, soy, salty, cereal, caramel, chicken, methionine, vegetable, offaly, meaty, burnt, prawn, rancid, and bitter.

  The tasting protocols depended on the texture of what was being tasted. When munching on meat chunks people assessed the hardness, chewiness, and grittiness (‘sample chewed using molars until masticated to the point of being ready to swallow’). But they gauged gravy/gel glops for viscosity and grittiness (‘sample placed in mouth and moved across tongue’).

  The knowledge thus gained is only a first step. ‘It is now necessary’, Pickering writes, ‘to determine the usefulness and limits of sensory data gathered from human panels in describing and predicting food acceptance and preference behaviours in cats.’

  Where the Pickering cat food paper was mainly for industrial consumption, a team of independent scholars – comprised of John Bohannon, Robin Goldstein, and Alexis Herschkowitsch – published ‘Can People Distinguish Pâté From Dog Food?’ to address a societal concern: ‘the potential of canned dog food for human consumption by assessing its palatability alone’. The study concludes somewhat perplexedly that (1) ‘human beings do not enjoy eating dog food’ and (2) are ‘not able to distinguish its flavor profile from other meat-based products that are intended for human consumption’.

  Perhaps alcohol helped this to happen. The dog monograph is published by the American Association of Wine Economists (AAWE), while the cat paper is written by a professor of biological sciences/wine science, and appears in the Journal of Animal Physiology and Animal Nutrition, which serves up complementary studies such as ‘The Influence of Polyphenol Rich Apple Pomace or Red-Wine Pomace Diet on the Gut Morphology in Weaning Piglets’.

  Pickering, G. J. (2009). ‘Optimizing the Sensory Characteristics and Acceptance of Canned Cat Food: Use of a Human Taste Panel.’ Journal of Animal Physiology and Animal Nutrition 93 (1): 52–60.

  Bohannon, John, Robin Goldstein, and Alexis Herschkowitsch (2007). ‘Can People Distinguish Pâté From Dog Food?’ AAWE Working Paper no. 36, April.

  Measured Attitudes to Chocolate

  A report called ‘The Development of the Attitudes to Chocolate Questionnaire’, published in 1998, tells how three researchers at the University of Wales, Swansea, cooked up a new analytic tool.

  Psychologists had long craved a way to assess someone’s craving for chocolate. Why chocolate? Because ‘chocolate is by
far the most commonly craved food’. It tempts chocoholics, and also academics who hunger for knowledge and perhaps recognition.

  The desired goal – the perhaps impossible dream – is to measure and compare any two people’s chocolate cravings as reliably as one can measure and compare the heights of two tables. But cravings are often intertwined with emotions, and table heights are not. This explains why table heights are easier to measure.

  All prior attempts to measure cravings, say study co-authors, David Benton, Karen Greenfield, and Michael Morgan, were ‘unreliable’. They devised a tool that, they say, ‘provides a quantitative estimate of the fundamental attitudes to chocolate’. It measures the magnitude of the craving; it also measures the guilt feelings.

  The tool – called the Attitudes to Chocolate Questionnaire – is a simple list of twenty-four statements. Some are strictly about craving:

  The thought of chocolate often distracts me from what I am doing.

  My desire for chocolate often seems overpowering.

  Some are about guilt:

  I feel guilty after eating

  often wish I hadn’t.

  To measure an individual’s chocolate craving, have the person read each statement and then indicate, by marking on a little ruled line, whether the statement is ‘not at all like me’ or ‘very much like me’ or somewhere in between. A bit of statistical manipulation, and hey, presto! out pops a set of numbers that describe the craving.

  Benton, Greenfield, and Morgan tested and calibrated their new tool on some student volunteers. In addition to answering the questionnaire, the volunteers played a sort of mechanical game. By pressing a lever, they could obtain a reward – a little button made of chocolate. As the game progressed, they had to press the bar more and more times (twice, then four times, then eight, then sixteen, etc.) before another chocolate would pop out. The point at which someone refused to keep playing this game indicated the strength of their craving (or, one might argue after some time has passed, the fullness of their stomach).