Plantas

J Am Oil Chem Soc (2011) 88:1795–1798 DOI 10.1007/s11746-011-1849-1

ORIGINAL ARTICLE

Single Soybean Seed NMR Calibration for Oil Measurement Using Commercial Cooking Oils
Golsa Samii-Saket • Jeffrey G. Boersma • Gary R. Ablett • Duane E. Falk • Ron Fletcher Istvan Rajcan
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Received: 23 December 2010 / Revised: 21 April 2011 / Accepted: 22 April 2011 / Published online: 13 May 2011 ÓAOCS 2011

Abstract Development of high oil soybeans would reduce the cost of soybean oil production for biodiesel or edible oil applications. An accurate determination of soybean seed oil concentration is essential especially when developing superior cultivars with increased seed oil content. The objective of this study was to develop an oil measurement method for single seeds using NMRspectrometry. An NMR spectrometer was calibrated using commercial cooking oil. Fifteen cultivars of known mean oil content were used to evaluate the calibration curves. The calibration curves developed had a correlation coefficient of 0.99. It was found that soybean and corn oil gave identical results over the calibrated interval. Keywords Soybean Á Oil content Á NMR spectrometer Á Single seed oilmeasurement

Introduction Increasing soybean oil content would reduce the production cost of soybean oil for biodiesel or edible oil applications. Improving soybean oil concentration has historically received less attention than improving protein content hence there are few studies with the aim of increasing soybean oil content [1–3].

G. R. Ablett is deceased. G. Samii-Saket Á J. G. Boersma Á G. R.Ablett Á D. E. Falk Á R. Fletcher Á I. Rajcan (&) Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1, Canada e-mail: irajcan@uoguelph.ca

An accurate determination of soybean seed oil concentration is essential for the development of superior cultivars especially when the aim is increasing seed oil content. Like near infra-red spectrometry (NIRS),nuclear magnetic resonance spectrometry (NMR) is an accurate, rapid and non-destructive method of measuring oil content in living seeds [4] and may be used to determine the oil content in either a single seed or bulk samples [5, 6]. Determination of oil content in a single seed could facilitate and accelerate the breeding and development of cultivars with higher oil content [7]. Previously, a smallnumber of studies have applied NMR to oil measurements of single seeds, including those by Conway (maize, 1960) [8], Alexander et al. (maize, 1967) [5] and Collins et al. (soybean, 1967) [9]. All three used continuous wave (CW) spectrometers that could not discriminate between water and oil within the seed, unlike the more recent pulsed NMR spectrometers that use the ‘spin-echo’ method [10]. Theythus required seeds to be dried to 3–4% moisture first [9]. Calibration of the NMR spectrometer is critical for obtaining accurate, meaningful results that may be useful to both breeders and end-users such as crushing facilities. In previous reports, calibration of the NMR was achieved by adding precise amounts of oil to de-fatted crushed seed [5]; gravimetric extraction and analysis of a single seedfrom each of several matched pairs, with the intact seed becoming a known standard [9] and, calibration with pure oil recently extracted from seed [11]. The objective of this study was to develop a single seed oil measurement method using NMR spectrometry that could be used by plant breeders to select single seeds of high oil content, with the intent of developing high oil soybean cultivars.123

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J Am Oil Chem Soc (2011) 88:1795–1798

Materials and Methods Plant Material Twelve soybean cultivars having a range in oil contents from approximately 16–22% were selected using NIRS. Several cultivars were grown in more than 1 year, to give a total of 15 samples (Table 1). NIRS Seed Oil Analysis Seed samples (*300 g) of a range of cultivars were analyzed for oil content by NIRS...