International Sugar Journal
The Blackboard

Cane maturity testing [Registered]

In 1935 ISSCT held a symposium on methods to determine the maturity of sugarcane; a presentation from Nath & Kasinath gives references from work done in 1915 and 1916 in Malaysia and India. Kerr (1935) describes a method based on randomly sampling 10 stalks which were then divided into three equal lengths, namely top (Tp), middle (Mi) and bottom (Bo);

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Sugarcane breeding: Conclusions [Registered]

Breeding work has been published regularly in cane sugar literature, often by the same author over many years. H H Dodds for example published 7 papers from 1926 to 1944 and P G C Brett 6 from 1947 to 1957, in SASTA proceedings. In Australia J H Buzacott, K R Gard, M K Butterfield, D M Hogarth & N Berding and M C Cox et al published from 1950 to 2014.

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Sugarcane breeding: Early history [Registered]

The industry does not “make” sugar: it extracts it from sugarcane; the wellbeing and quality of this plant are therefore critical for commercial ventures to survive. If the climate and […]

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The use of lead salts in the laboratory [Registered]

Browne & Zerban (1948) quote Scheibler who in 1875 investigated a “double dilution” method to reduce the error caused by the lead precipitate in saccharimetry; Pellet & Sachs in 1880 […]

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Entrainment – Sampling & Analysis [Full subscriber]

Sampling condensed vapours and condenser waters is never easy. Beale (1959, 1962) and Claire (1965, 1967) mention practical difficulties encountered. Vapour sampling involves iso-kinetic (constant velocity) principles which require sophisticated equipment to obtain representative condensed vapour samples. Most workers have sampled condensates and condenser waters, using simplified sampling equipment. One of the problems associated with condenser waters is that the inlet water usually contains sugar. The large volumes of water and low concentrations of sugar can cause serious errors. A simple calculation illustrates the difficulty; we assume that the condenser inlet and outlet waters contain 70ppm of sugar, that 1 ton of vapour requires 30 tons of inlet water, and that the analytical precision is ±1ppm.

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Entrainment – basic concepts [Registered]

Spencer & Meade (1948) state that during evaporation there is always the possibility of sucrose loss due to the carrying over, or entrainment, of small drops of juice or syrup […]

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Brix free water – the concept [Registered]

Heintz in 1874 showed that when air-dried and sugar free beet “marc” (the beet components remaining after complete aqueous extraction of the soluble constituents) is placed in a sugar solution […]

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Milling performance [Registered]

An interesting aspect of milling is the evaluation of the performance of each mill in the tandem. Early (1921-1931) analytical techniques are described in Browne & Zerban (1948); sampling is discussed in the SASTA Laboratory Manual (1985). Material balances across milling tandems normally use 4 main assumptions which are not all rigorously correct:

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Chemical Cleaning of Evaporators [Registered]

Literature on the chemical cleaning of evaporators was available in 1929 (Spencer & Meade; 1948); in most cases sodium hydroxide and soda ash were boiled individually or as mixtures in the vessels which were then drained and washed. A boiling with hydrochloric acid would follow if necessary. Spraying techniques in Java and Hawaii were seen to be more economical in terms of chemical quantities. Fermented molasses was used in Queensland in the early 1930’s, and Honig (1953) quotes results obtained in 1949 from Taiwan.

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Mechanical cleaning of evaporators [Registered]

Although mechanical cleaning of evaporators must have been used in many cane sugar industries, the topic is not well covered in the literature. There are a number of reasons for […]

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