Nergi® delight: preliminary sensory evaluation of fresh and transformed baby kiwi by-products

Cultivation of baby kiwi (Actinidia arguta), commercially presented as Nergi®, in the Piedmont region has a significant role in terms of production, contributing to a growing but still niche market. The berries’ metabolism has not been completely understood yet, resulting in difficulties in storage management that lead to high quantity of by-products that do not meet fresh market requirements. This study addresses these challenges by exploring the key attributes of Nergi® through the development of a standardized sensory vocabulary that effectively describes both fresh and processed baby kiwi (dried, freeze-dried blended pulp, freeze dried pieces). Berries (Nergi® cv. Rua) non-compliant with fresh market have been collected post-storage from the packhouse. Part of them have been dried and freeze-dried in the DISAFA laboratory. Sensory description and quantitative descriptive analysis (QDA) have been performed by a semi-trained panel organized inside the department. Vocabulary was built to describe all the products. The transformed product was recognized different specifically in terms of taste, aroma and flavor from the initial fresh Nergi®, highlighting the development of umami taste and changes in the fruity profile. The pungent sensation was an issue according to the panelists for the freeze-dried product and may be related to the inflammation produced by polyphenols in the mouth and the presence of tannins. In some cases, the bitter taste was also recognized as compromising the overall assessment. The sensory characterization of A. arguta is related to the investigation of overall berries quality and defining selling criteria. The sensory vocabulary developed could potentially be used as a tool to infer the level of other physico-chemical characteristics based on the presence, absence or intensity of specific descriptors, offering an integrative method for fruit evaluation and product sensory standardization with attention towards consumer appreciation.