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Glycoalkaloids and Potatoes

Processing Potatoes

Specific gravity of potatoes:- Reviewing the procedure for specific gravity measurement of potato tubers: Published by the Kimberly Research and Extension Center, University of Idaho (Kiran Shetty). Of particular interest is this handy table to help estimating the total solids of the potatoes from the calculated specific gravity measurements:

Specific gravity of potatoes:

Paper by Murray Hegney, Vegetable Research Officer, Manjirnup Horticultural Research Centre, Western Australia. Solids recovery technology for processing plants Water & Oil Technologies Inc is an Illinois, US company providing technology that incorporates the use of natural flocculents (without the use of pH adjustment) for soluble and insoluble solids recovery from scrubber or blanching water in potato processing.

According to Ed Laurent, President of the company, successful data obtained while testing at three potato processing plants in Idaho, the natural flocculent treatment cost is between $5.50-$6.00 (U.S. currency) per 1000 US-gallons (3800 liters) treated. The treatment does not add to nitrate levels, which are a primary concern, since the effluent water is applied to land near the Snake river.

The water quality in the land leacheate is monitored for its nitrate levels. The technology allows water to be recycled for re-use for scrubbing potatoes. The dried solids can be used in animal feed supplements, as a fertilizer, or for fuel in electrical generation for which Water & Oil Technologies, Inc. also has a patent.

According to Mr Laurent: “We are proud to introduce our findings and look forward to applying this technology to give potato processing plants greater efficiency, increased income from by-product use, and diminished environmental headaches. We at Water & Oil Technologies, Inc. look forward to demonstrating the many benefits that this technological breakthrough can provide to the potato processing industry throughout the world.”

Precision Farming

A Precision farming primer:- The “Precision Farming Primer” is the new online “how-to guide” for harnessing geographic information systems (GIS), GPS, and other site-specific technologies for enhanced management of production agriculture. This online curriculum will help teach you to move from maps to management as you learn to turn your data into decisions.

Research Notes

Genome Database for the Solanaceae:- SolGenes is a U.S.D.A.-funded Genome Database for the Solanaceae, containing information about potatoes, tomatoes, peppers, and related species. SolGenes is one of several plant genome databases supported by the USDA/NAL Plant Genome Research Program. It serves the international community of geneticists and breeders who work with tomatoes, potatoes, peppers, and other Solanaceous species. Boron Rate Studies On Alfalfa And Potatoes In Colorado Personnel from the Colorado State University (Golden Plains Area Cooperative Extension) studied the impact of boron on potatoes and alfalfa.

In 1998, three boron test sites were studied in Colorado, two with alfalfa and one with potatoes. In all three tests, soil samples were taken prior to test initiation to confirm that soil B levels were low. The alfalfa tests evaluated five application rates: 0, 0.5, 1.0, 2.0, and 4.0 lbs. B/A; and the potato test evaluated three rates (0, 1, and 2 lbs. B/A) on two cultivars (Russet Norkotah and Russet Nugget).

More information about essential plant nutrients can be found here.


RP-HPLC Analysis of Glycoalkaloids in Potato Tubers
Glycoalkaloids are natural toxins, occurring in all parts of plants of the Solanum species. Glycoalkaloids are toxic to humans; the lethal dose is considered to be 3-6 mg per kg body mass.

Commercial and especially new potato varieties are routinely screened at the Netherlands Institute for Carbohydrate Research TNO for their solanidine glycoalkaloid content, with a HPLC method. Robert Houben and Kommer Brunt from the Institute explain in the above article how some aspects of the HPLC method have been optimized. Detection and quantification of glycoalkaloids The USDA-Office of Technology Transfer holds the rights to technology that detect and quantify glycoalkaloids.

Greening of potatoes

According to information contained in a fact sheet by Food Science Australia, glycoalkaloids are at high levels in the leaves, stems and sprouts of the potato plant and are normally at very low levels in potato tubers. However, on exposure to light the potato tuber will produce elevated levels of these protective glycoalkaloids, with the highest levels being in the sprouts as they emerge from the tuber.

Potatoes will also produce high levels of glycoalkaloids (such as solanine) in response to bruising, cutting and other forms of physical damage, as well as to rotting caused by fungi or bacteria. In these instances high levels of glycoalkaloids are present in the potato. However in non-damaged potatoes, greening is a warning sign. Neural tube defects and potato consumption In a recent paper delivered at a Pediatrics Congress (Symposium of Congenital Malformations) held in Barquisimeto-Lara, Venezuela, Ruben Dario Cortez said that there is a relationship between the consumption of damaged and green potatoes, and neural tube defects.

Meetings: Potatoes in Practice

The British Potato Council, together with the Scottish Crop Research Institute, and SAC, has launched a new event, Potatoes in Practice, which is being planned as the biggest potato event in Scotland in 1999. And this year it will be held on “The Glorious 12th” (August). Like its more southerly brother, British Potato ’99, it will target agronomy aspects of production and provide a forum for the whole industry from seed production to supermarket shelf.

Farmers, advisers, and others connected with the potato industry will have the opportunity to view the SCRI and SAC trials at a single site. Global Conference on Potato. Global Conference on Potato is being organized by the Indian Potato Association (IPA) in collaboration with the Central Potato Research Institute (CPRI), Simla, India. It will be held at the Indian Agricultural Research Institute (IARI), New Delhi, India from December 6-10, 1999. The theme of the Conference is “Fighting Hunger with Potato”. The Conference has seven theme-based sessions:

  1. Crop Production, Cropping Systems and Crop Modeling
  2.  Potato Biotechnology
  3.  Genetic Resources and Crop Improvement
  4.  Diseases & Pest Management and Seed Production
  5.  Potato Late Blight
  6.  Potato Storage, Processing and Marketing
  7.  TPS and other Non-conventional Methods of Propagation

Several National and International agencies/organizations are also involved in the organization of this Conference. International Potato Centre (CIP), Lima, Peru is sponsoring the symposium on “Potato Storage, Processing and Marketing”. The “Late Blight” symposium is being sponsored by CEEM-Cornell University, whereas the symposium on “Potato Biotechnology” is being sponsored by the Department of Biotechnology, Government of India. Agrico Quality (Calcutta) is one of the main sponsors of this Conference.