No abstract

No abstract

No abstract

The changes in weight and quality of sugarbeet roots stored in 18 clamps, mostly in eastern England during the winters of 1992/93 to 1994/95, were studied on farms using best commercial practice. Storage usually started in early December, at about the last recommended date of harvesting, and continued until the end of the beet-processing campaign at the local sugar factory (usually in February). Random samples of beet, in open-weave nets, were either analysed at the outset or were buried in a predetermined pattern in the clamp for up to 84 days. Periodically, samples were removed from the clamps for analysis. Beet weight hardly changed but sugar was lost as a reduction in sugar concentration: this declined at c. 0·02% per day. The concentration of reducing sugars, which are important impurities, increased fourfold during storage. Most other beet quality parameters remained unchanged. Sugar and adjusted weight was lost at 0·143 and 0·187% per day respectively. This relationship was highly significant, but a relationship between sugar loss and accumulated thermal time (0·0188% per °C day) accounted for more of the variation (73%). Temperature changes within the clamps, and the differences between clamps in accumulated thermal time, were not predictable. Some clamp insulation materials appear to allow more heat to accumulate than is desirable.

Studies in the 1970s showed that sugar beet partitioned into root, crown and scalp had large concentrations of impurities in the scalp, the root portion had the best processing quality and the crown was intermediate. Since then the processing quality of beet has improved. This paper reports similar studies on today's varieties, in an experiment at IACR‐Broom's Barn over the three years 1993–1995, and extended in 1996 to the most important soil types used for sugar beet production in England. The crown is now a smaller proportion of the total beet weight (70 compared to 130 g kg−1) but the distribution of the concentrations of the quality parameters (sugar and the impurities potassium, sodium, amino nitrogen, raffinose, betaine and invert sugars) between the beet portions has not changed. This distribution was not significantly affected by year, variety or beet size but was affected by soil type. Nitrogen‐rich soils produced beet with heavier crowns and a smaller differential in impurity concentration between the root and the crown. The scalp material had a variable sugar concentration, but it always contained large concentrations of impurities, especially invert sugar. The equation of Pollach et al (Zucker industrie 116: 689–700 (1991)) which includes invert sugar as a variable, was applied to the data. It indicated that including all the crowns in the factory process with the roots would increase white sugar yield by approximately 6%. The increase due to inclusion of the scalp was much smaller (2%), and would probably be expensive to achieve. © 1999 Society of Chemical Industry