Sugarbeet biochemical quality changes during pile storage. Part I. Sugars.
Martin, S. S., Narum, J. A. and Chambers, K. H.
Journal of Sugar Beet Research. Volume 38, Number 1, 2001. Pages 35-53.
2001
บทคัดย่อ
Sucrose and quality losses in pile-stored sugarbeets have financial implications for growers and processers alike. Groups of locally adapted varieties were grown and pile stored at Sidney (Montana, USA), Worland (Wyoming, USA), and Hereford (Texas, USA) to investigate varietal effect on losses during storage. Paired root samples were prepared at harvest. One of each pair was immediately analysed for sucrose by polarimetry (pol), and a portion of each sucrose filtrate was frozen for later HPLC analysis for "true" sucrose, glucose, fructose, and raffinose. The second sample of each pair, in an air-permeable bag, was placed into the factory storage pile and kept there from October or November 1989 until the following January: for 110 days at Sidney, 90 days at Worland, or 56 days at Hereford. These samples were then recovered and analysed in the same way as the unstored samples. Data were analysed separately for each location. Both at harvest and after storage, pol sucrose overestimated true sucrose concentration as determined by HPLC. At the three locations, the average pol error, i.e. the percentage by which pol sucrose minus HPLC sucrose differed from the HPLC sucrose value, was +2% to +19% at harvest, and +9% to +14% after storage. Only at Sidney was there a statistically significant decrease in true sucrose level during storage. Glucose and fructose concentrations were low at harvest and increased significantly with storage at each location. Significant varietal difference after storage occurred for glucose at Worland, and for fructose at Sidney and Worland. Raffinose concentrations at harvest were low at Sidney and Worland, increasing significantly with storage. Varietal difference for raffinose after pile storage occurred at Worland. The raffinose concentration was unexpectedly high at harvest at Hereford, but did not increase significantly during pile storage.