SENSORY PROPERTIES OF PURPLE ONIONS PLANTED IN VINH CHAU WARD WITH OTHERS IN VIETNAM

Abstract

Purple onion is a spice used in many Vietnamese dishes. Characteristics of products from spices are heavily affected by climatic and soil conditions. In this study, we investigated the sensory properties of purple onion products from different areas such as Tien Giang, Ly Son, Vinh Chau and Ninh Thuan.

The sensory study was conducted by a nine trained sensory panelists. Principal Component Analysis was used to analyse the data. The results showed that the purple onion planted in Vinh Chau ward, Soc Trang Province has typical sensory properties such as sweetness, typical flavor of purple onion, brittleness, violet color and feeling of spicy and high moisture, rounded shape; Meanwhile, the other purple onions planted  in Ly Son district (Quang Ngai Province)  and Ninh Hai district (Ninh Thuan province) have  the opposite characteristics of toughness, long shape and  bitter taste, bitter aftertaste.

This  results are significant in the development of a  list of sensory descriptive terms of purple onion. This is  an important  sensory science reference document for for researchers, producers and traders. The sensory data from this study is the basis for identifying the characteristics of Vinh Chau purple onion products with other purple onions in other regions of Vietnam.