Due to their differences in chemical structure and branching, Agave and chicory fructans do have different physico-chemical properties, e.g. the branched Agave fructans are significantly more soluble than linear chicory inulin. Given the differences in structure and physico-chemical behaviour between the two, it can be assumed that they also possess different nutritional properties. So, the way they are fermented by bacteria in the gut depends on the carbohydrate linkages, branching, degree of polymerisation, solubility, etc. Therefore, Agave fructans and chicory inulin will be broken down preferentially by different enzymes and different micro-organisms. Also, the speed of fermentation (and hence the place of fermentation in the colon), the bacteria stimulated and the end products derived from such different fermentation patterns will not be similar for both types of fructans. Given the importance of the types of bacteria involved in colonic fermentation and their recognised benefits (e.g. bifidobacteria) on the human organism, the question whether Agave fructans have any health-related benefits is still open.
It has indeed to be reminded that most nutritional research in animal models and in human intervention studies has been done specifically on chicory inulin (and oligofructose). Given their different chemical structure and behaviour, the nutritional and health benefits of the chicory-based ingredients can in no way be extrapolated to Agave fructans. To be considered as functional food ingredients and offer any possibility for health claims, Agave fructans (sometimes erroneously called ‘agave inulin’) will first have to demonstrate their nutritional properties and benefits in scientifically sound (human) studies.
Lopez MG, Mancilla-Margalli NA, Mendoza-Diaz G (2003) Molecular structures of fructans from Agave tequilana Weber var. azul. J. Agric. Food Chem. 51:7835-7840.
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