A Potato Glossary A Potato Glossary by Richard E. Tucker Last revised 15 Sep 2016 Copyright © 2016 by Richard E. Tucker Introduction This glossary has been prepared as a companion to A Potato Chronology. In that work, a self-imposed requirement to limit each entry to a single line forced the use of technical phrases, scientific words, jargon and terminology that may be unfamiliar to many, even to those in the potato business. It is hoped that this glossary will aid those using that chronology, and it is hoped that it may become a useful reference for anyone interested in learning more about potatoes, farming and gardening. There was a time, a century or more ago, when nearly everyone was familiar with farming life, the raising of potatoes in particular and the lingo of farming in general. They were farmers themselves, they had relatives who farmed, they knew someone who was a farmer, or they worked on a nearby farm during their youth. Then, nearly everyone grew potatoes in their gardens and sold the extra. But that was a long ago time. Now the general population is now separated from the farm by several generations. Only about 2 % of the US population lives on a farm and only a tiny few more even know anyone who lives on a farm. Words and phrases used by farmers in general and potato growers in particular are now unfamiliar to most Americans. Additionally, farming has become an increasingly complex and technical endeavor. Research on the cutting edge of science is leading to new production techniques, new handling practices, new varieties, new understanding of plant physiology, soil and pest ecology, and other advances too numerous to mention. Suffice it to say, it is becoming difficult to understand the newest findings and advances without at least a rudimentary understanding of the terms and phrases used in the business. Indeed, many farmers do not know the technical jargon of their own field. This writer must admit that even though he grew up on a potato farm, still has close relatives working it and still dabbles in it from time to time, he has had to look up many, if not the majority, of these words and phrases because the nuances of each were not clear or indeed were completely unfamiliar. Extrapolating this to the general public leads one to conclude that there must be a huge gap of understanding between farmers and consumers. This writer can only conclude that this work ought to be useful, if not valuable now, and will only become increasingly valuable as time goes on. This writer welcomes clarifications and corrections for he is sure mistakes and misrepresentations have crept in. This continues to be a work in progress; revisions will be issued periodically. Please forward any corrections, edits, new information and special requests to [email protected] Readers will note some entries have no definition. This is not an error or problem with your computer; these are place holders for items yet to be researched. A Potato Glossary Abiotic In biology, the non-living parts of the environment that affect living organisms including plants. This includes many environmental variables such as water, light/shade, temperature, wind, soil, altitude, latitude, sun angle, etc. and physical factors such as chemicals (pollution), bruising, poor handling, etc. Accession identifier An identifier recorded when an accession is enetered in a genebank or germplasm collection. Accession number A number intended to serve as a unique identifier for an accession. This number, once assigned, can never be re-assigned to another accession, even when an accession becomes extinct, its assigned accession number is still not available for re-use. Accession numbers Tucker Farms, Inc. 1 15 September 2016 A Potato Glossary are alpha-numeric, composed of a thee-letter abbreviation, left justified, followed by up to seven digits, right justified. Acrylamide A processing contaminant found in some cooked foods discovered in 2002 at which time it created a huge stir in the world-wide potato industry. While there is even now (2016) no concrete proof that acrylamide causes cancer in humans, the fact that it causes cancer in rodents is undisputed. Accordingly, acrylamide is being closely watched by most regulating authorities, including European Food Safety Authority (EFSA), the Food and Agriculture Organization (FAO), and the World Health Organization (WHO) as well as some producer groups such as the Confederation of the Food and Drink Industries in the European Union (CIAA). Interestingly, the USDA ARS is not officially listed among these organizations. Nonetheless, unofficially, the USDA ARS is closely watching such research and indeed is conducting its own research. Due to the uncertainties regarding the health effects of acrylamide, its presence in the human diet is a concern. The potato industry is working hard to address this concern. Acrylamide has the chemical formula C3H5NO. Its IUPAC name is prop-2- enamide. It is formed by way of the Maillard reaction where free amino acids react with asparagine and reducing sugars (glucose/fructose) at high temperatures to produce a plethora of flavor, aroma and color compounds. This process begins slowly as cooking temperature rises, but when the temperature hits 338 °F, the formation of acrylamide accelerates remarkably as reducing sugars combine with the amino acid asparagine, especially in low moisture conditions. This commonly occurs in many foods when frying, baking, roasting, and broiling, especially when ‘browning’, which adds color, texture and taste to many foods people love to eat. Acrylamide is also commonly found in fried or baked goods such as French fries, potato chips, breakfast cereals, toasted bread, cookies, and surprisingly, coffee. Temperatures below 248 °F have shown no increase in acrylamide. Consequently, boiling and microwaving are less likely to create acrylamide because temperatures rarely exceed 212 °F. The longer foods remain at high temperatures the greater the production of acrylamide. Researchers at Rothamsted Research in the UK during three-year research program focused on genetics, agronomy and storage. They looked at varietal differences and the effects of storage on acrylamide formation in commercial varieties. The range is huge with acrylamide levels as low as 104 ppb to as high as 5,250 ppb. In agronomic tests, researchers discovered that nitrogen and sulphur have a strong effect on acrylamide formation in potatoes. Water stress (drought) was also found to have a strong effect on acrylamide formation in potatoes with different cultivars reacting quite differently. Unfortunately, Russet Burbank, the American gold standard for taste, aroma, color and texture in French fries is particularly prone to developing high levels of reducing sugars as well as acrylamide. Potato cultivars with low levels of reducing sugars and/or free asparagine in tubers would be a means of reducing acrylamide in processed potato products. For several decades, potato breeders have bred for reduced tuber sugar levels to facilitate the development of frying cultivars having lighter fry or chip color. Fortuitously, breeding for reduced sugar levels in potato has also contributed to reducing acrylamide. However, efforts in reducing the concentration of asparagine in potato were not a breeding objective until the recent elucidation of the role in acrylamide formation. In potato, asparagine concentrations are in excess compared to reducing sugar content, with the conclusion being that acrylamide formation will be determined largely by reducing sugar levels. However, while the majority of published data show stronger correlations between Tucker Farms, Inc. 2 15 September 2016 A Potato Glossary reducing sugars and acrylamide formation than for asparagine, cold-induced sweetening in tubers following storage can change the balance, with reducing sugars no longer being limiting and asparagine content now becoming critical in acrylamide formation. A combined breeding approach for reducing acrylamide formation by lowering concentrations of both tuber reducing sugars and free asparagine appears warranted. To that end, Simplot Plant Sciences of J.R. Simplot Company has developed a new GM potato variety, Innate®, with lower levels of asparagine which equates to 70% less acrylamide during processing. Some conventional cultivars and other GM cultivars offer solutions to the acrylamide issue as well. Current data suggests that no single food contributes a majority of acrylamide to the average diet in Europe or the US. It is estimated that acrylamide is present in 40 percent of the calories consumed in the typical American diet. While that number can vary in some countries, there’s nothing to suggest that eliminating any single food would significantly reduce the amount of acrylamide in the diet. Aerial plant That portion of the potato plant appearing above ground. It consists of the stems, leaves, blossoms, and fruits. When grown from seed pieces, several shoots (sprouts) may arise from a single seed piece. This occurrence may cause physiological disorders in the developing tubers, such as tuber greening and growth disorders if the stem density is too high. The growth of the stem is erect in early stages, reaching 2-5 feet in height, but depending on variety, growth habit will range from erect to partially erect to fully decumbent. Density of stems also influences the stem height. As stem density increases, so does the height, and with this there is a decrease in axillary branching which decreases the photosynthesis potential. As the plant matures, the stem weakens and lays prostrate, eventually yellowing and dying back at the end of the growing season. Aerial tuber Potato tubers that grow without soil and water. Agribusiness Producers and manufacturers of agricultural goods and services, such as fertilizer producers, farm equipment manufacturers, food and fiber processors, wholesalers, transporters, and retail food and fiber outlets. Agricultural Assessment In New York State, a “use value” tax assessment for eligible farmland. This allows farmland to be taxed for its agricultural value, rather than its market (i.e., non-farm development) value.