This article is the second in a two-part series on vanilla curing. Part 1 appeared in the July 2013 edition of Perfumer & Flavorist.
The pioneering work by Peter Lillford on food microstructure provided a basis for understanding the major structural elements of food materials that define their textural properties at the microscopic level. Extension of this thinking provided the platform for predicting the pathways for the breakdown of food structures in the environment of the oral cavity. The departitioning of tissue and cellular compartments has a profound effect on the textural properties of food matrices, and influences the formation and release of aroma and tasteactive inclusions. This microstructure approach can be applied to natural tissue materials undergoing major structural changes such as occur in plants during senescence. Natural senescence on the vine or curing of vanilla beans signals major cellular and tissue changes. Major biochemical events occur as a consequence of these processes, namely hydrolytic release of vanillin and related phenols from their β-D-glucosides, and the concomitant “browning” of the tissue.
Part 1 of this review examined the microstructure of the ripe vanilla bean and the compartmentation of the key enzymes and chemical actives that contribute to flavor and color formation during natural post-ripening and curing. This review, Part 2, considers the effect of the senescence process and the decompartmentation that occurs as a consequence of microstructure disassembly of the vanilla pod. These relate to major flavor and color changes that occur during the natural ripening and the induced curing process.