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Fructose has recently received much attention due to renewed interest in natural sweeteners. In addition, fructose has some advantages to sucrose in sweetness, solubility, viscosity, and dental health characteristics. Fructose is deposited as storage fructans of the inulin (beta-1,2) type in tubers and rhizomes of the Compositae family. The utilization of the Jerusalem artichoke (Helianthus tuberosus) tuber as a source of fructose syrup is discussed. This plant has the potential to produce more sugar per acre than corn or sugar beets. In addition, the artichoke has higher frost resistance and lower heat unit requirements than corn and is somewhat more tolerant to low moisture conditions than sugar beets. A high quality fructose syrup can be produced from artichoke tubers. The extraction step was found to be particularly important since development of adverse colors and flavors must be prevented. The fructans may be acid or enzyme hydrolyzed but the latter method gave a higher quality syrup. Ion-exchange resins and activated charcoal were effective in removing coloring and flavoring materials, and also reduced other noncarbohydrate constituents. Since the enzymatic hydrolysis of the fructans is an attractive alternative to acid hydrolysis, a process was developed for producing and purifying a special beta-fructofuranosidase (inulase) from Saccharomyces fragilis. Inulase has a much higher specificity for fructans than commerically available beta-fructofuranosidase (invertase).

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As measured by the Brabender viscoamylograph, alkali-cooking and soaking of maize in water (nixtamalization) caused large increases in viscosity, as compared with native flour. Marked effects of cooking time on the pasting properties of nixtamal were also observed. As assessed by the blue value method, nixtamalization does not cause extensive gelatinization of the starch. This was supported by differential scanning calorimetric studies, which yielded similar gelatinization endotherms for untreated maize and nixtamal flours. However, no endotherm peak appeared in tortilla samples made from this nixtamal. Furthermore, untreated maize and nixtamal flours contained many unswollen starch granules.

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