Pounds upon pounds upon pounds of potato chips are consumed each day. Few give the hard work on the farm or science and teamwork required to bring good chips to market one thought. Here, though, is a brief summary of recent activity in Ohio and elsewhere designed to help growers and processors and all others who rely directly and indirectly on local-regional “chip business.”
The Big Picture. USDA (e.g., https://www.nass.usda.gov/Publications/Todays_Reports/reports/pots0918.pdf) and other information makes clear that potato production and processing remain important, enormously valuable industries throughout the U.S., Great Lakes, and, still, Ohio. Nearby on the ground evidence includes Lennard Agriculture (https://www.lennardag.com/) and impressive investments it and its cooperators have made in infrastructure (e.g., center pivot irrigation systems), expertise, research, and other assets in a four-county area of the Scioto River Valley, among other locations. Early, summertime harvests of large, high-quality crops suitable for use in chip-making are important to them. This activity maintains the strong tradition of supplying local-regional chipmakers … page 20 of the USDA report mentioned earlier shows that the U.S. contains approximately 89 chip-making plants with 15 (16% of the total) located within Michigan, Ohio, and West Virginia. Thankfully in this case, it appears that little has changed since 2008 (https://www.potatopro.com/news/2008/ohio-boasts-second-most-potato-chip-manufacturers-us) and before.
Potatoes used to make chips must meet strict specifications. Tuber shape, size, specific gravity, sugar/starch content, flesh color, natural or man-made damage, and other characteristics influence the chip-maker’s desire for the crop. Since these traits hinge on each combination of potato variety, crop management, and growing conditions, the pressure is on growers to optimize each combination. Improved varieties better able to thrive in various conditions are always needed. With important exceptions, potato varieties used in chip-making in the U.S are bred by teams at USDA and a small number of universities, including Michigan State Univ. (http://potatobg.css.msu.edu/). In 2019, led by Chris Long of MSUE (https://www.canr.msu.edu/people/christopher_long), plots of a total of fifteen experimental selections from MSU, USDA, Cornell Univ., and North Carolina State Univ. were planted alongside ones of “check” varieties in fields in Ohio coordinated by Lennard Agriculture. During Aug 13-16, the OSUE team including Chris Bruynis and Ross Meeker (https://ross.osu.edu/about/staff), Brad Bergefurd (https://scioto.osu.edu/about/staff), Mike Estadt (https://pickaway.osu.edu/about/staff), Will Hamman (https://pike.osu.edu/about/staff), and the VPSL (http://u.osu.edu/vegprolab/) harvested the plots and collected key data on the tubers. The VPSL has a long history of cooperating with potato breeders and others in developing improved varieties (e.g., see reports at http://u.osu.edu/vegprolab/technical-reports/).
Yield was measured first and it ranged from 1.3 to 2.6 pounds per foot of row across all selections and varieties (these values equate to 226 and 452 hundred-weight/acre, resp.). Tuber specific gravity (S.G.) using the weight in air, weight in water method and a hygrometer was measured next (see URL above). This method involves placing exactly eight pounds of tubers (air, at left) into a basket attached to an air-filled bulb and calibrated meter. The basket-bulb-meter unit is then placed in water (middle and right). It will sink to a depth roughly consistent with the tubers’ combined moisture and dry matter (especially sugar/starch) levels. Tubers high in S.G. are needed in chip-making; S.G. is influenced by variety, management (especially nutrient and irrigation), and other environmental factors. The S.G. of experimental selections … lines still being tested and not yet named … is always benchmarked against the specific gravity of well-known standard varieties.
Next, tubers were peeled and placed in cold water until chipped. Tuber flesh that has been damaged and exposed to air typically begins to oxidize and brown. Submersion in cold water slows the process. Commercial chip-makers and other potato processors remove potato skin using various methods often involving pressure and/or steam.
In commercial chip-making, peeled tubers are then sliced to product-specific thicknesses. Chip enthusiasts know that products vary in chip thickness, a variable that has multiple significant implications for the chip-maker and for research teams working on their behalf. Slice thickness influences fry time, oil-absorption, chip texture, and many other variables which influence the suitability of a variety for the specific product. As in our other potato research, here, we produced slices measuring 0.051 inches thick using a DeBuyer Kobra mandolin slicer.
Slices were then fried for 3.5 minutes using oil provided by a local chip-maker (Shearer’s Foods, Inc.) and a standard tabletop fryer (left). The target oil temperature was 350 deg F and the actual oil temperature was monitored throughout and allowed to reach the target between batches. Finally, the color of completed batches was scored against the industry-wide standard Color Chart developed by the Snack Food Association of America (sfa.org; below right). A rating of 1 (upper left of chart) is desired by most chip-makers. Many batches completed on 8/16/19 using tubers harvested in the Scioto River Valley area scored 1-3, a very promising result. Remaining tubers have been placed in cold storage and will be chipped again later, as one assessment of the rate at which each genotype converts starch to sugar when exposed to storage-like temperatures.
Land. Equipment. Good varieties and growing methods. Proper inputs. And, crop-friendly weather. These are just some of the resources needed for success on the farm. However, a great team is also essential … just as in research, extension, and other activities. In 2019, for the VPSL, like for other teams, data collection is ongoing. The potato evaluation outlined here will be followed by work with tomato, squash, watermelon, carrot, and other crops, with plots in fields and high tunnels and at OARDC and on commercial farms.