THE EFFECT OF AGEING TEMPERATURE ON THE SENSORY QUALITIES OF HIBISCUS SABDARIFFA   (ROSELLE) WINE

Wine, unlike most other food items can be stored for a very long time as ageing is positively correlated with wines of peak quality. However, as important as ageing is to wine quality, the temperature at which the wine is stored is even more critical as this factor alone can make or compromise the ageing process, thereby impacting the final organoleptic quality of the product. The aim of this study was to evaluate the impact of ageing temperature (6, 15 and 30 °C) for a period of 12 months on the sensorial attributes of roselle wine (Hibiscus sabdariffa wine). To achieve this, a sixty (60) sensory member panel (male and female) consisting of both experts and non-experts wine drinkers were recruited for the analysis. A balanced incomplete block (BIB) design was used for the study and the rating of the wine samples was based on a modified University of California Davis quality assessment rating of red wines. The data collected from the sensory evaluation was processed using the R.3.30 agricolae software package. The least square differences (LSD) was used to compare the mean ratings of the sensory attributes and significant differences between sample sensory attributes was established at p-value=0.05. The sensory data showed that in terms of colour rating on a scale of zero to three (where 0= poor; 3= excellent), wines aged at 6, 15 °C and 30 °C scored 2.31, 2.24 and 2.06, respectively. Although, there was no significant difference (p < 0.05) between samples at 6 and 15 °C in aroma and bouquet attributes, wines aged at 30 °C were significantly different (p < 0.05) from wines stored at 6 °C. With regards to the overall rating or final impressions of the wine samples, the data showed that wines aged at 6 and 15 °C had better scores those aged at 30 °C. The outcome of this study suggests that low temperature storage might enhance roselle wine organoleptic properties.

Keywords
Hibiscus sabdariffa; roselle wine; ageing temperature; sensory analysis; quality attribute