Radojka N. Razmovski

Experiences in Cultivation, Processing and Application of Jerusalem Artichoke (Helianthus Tuberosus L.) in Yugoslavia

ABSTRACT Investigations were carried out on three topics: (i) cultivation of Jerusalem artichoke, (ii) optimization of analytical procedures, and (iii) optimization of ethanol production. Agronomic investigations on the cultivation of Jerusalem artichoke has shown this crop to have a significant advantage over other ones with respect to biomass yield not only in fertile areas, but especially on marginal, i.e. sandy soils. In a number of experimental trials, an average fresh tuber yield of 40–80 t ha −1 together with an above-ground dry matter yield of 4 to 24 t ha −1 was recorded. Cultivar differences, a.o. regarding tuber yield, indicate possibilities of further improvement by plant breeding. Furthermore, yields could be increased by more adequate growing practices. Advanced analytical procedures, such as HPLC, were used to analyse the synthesis of inulin and its hydrolytic breakdown during the vegetation period and the post-harvest storage of Jerusalem artichoke tubers. Extraction of the tubers and purification of the raw juice resulted in a juice which, apart from high-polymer inulin, contained significant amounts of fructo-oligosaccharides as well as free glucose and fructose. Glucose usually appeared during inulin synthesis, whereas free fructose was found when degradation of polymers took place during tuber storage. Optimization of the process of ethanol production was focused on procedures with minimized energy consumption as well as on sources of enzymes needed. The highest yields of ethanol were obtained with Kluyveromyces marxianus. Using dense inocula an average ethanol yield of more than 90% of the theoretical could be attained. GC analysis showed larger inocula to lead to an increased content of acetaldehyde, but a decreased amount of ethylacetate. Concentrations of n -propanol, iso -butanol and iso -amylalcohol were largely independent of inoculum size. The composition of the stillages obtained after fermentation by K. marxianus and by Saccharomyces cerevisiae proved to be similar.

Some Possibilities for the Cultivation and Processing of Jerusalem artichoke (Helianthus tuberosus L.)

Abstract Investigations were carried out on the following; (i) the cultivation of Jerusalem artichoke : the advantages of J. artichoke as compared to other crops, (ii) advanced analytical procedures, such as HPLC, were used for the analyses of inulin synthesis and its hydrolytic breakdown and (III) ethanol production was focused on with respect to lower energy consumption with Kluyveromyces marxianus .