The Sensory and Physicochemical Properties of Honeybush Tea Depend on the Brewing Water: A Preliminary Study

Abstract

This study investigated how different water types affected honeybush (Cyclopia species) tea quality. Water types, varying in physicochemical properties, were used to brew tea from three honeybush species: C. intermedia, C. subternata, and C. genistoides (n = 6/species). The water types were deionized water (W1), two bottled spring waters (W2, W3), bottled reverse osmosis water (W4), brackish water (W5), and tap water (W6). Descriptive sensory analysis was used to determine whether water type affected the sensory profile of the infusions. Other parameters included CIEL*a*b* color and turbidity, as well as the soluble solids and phenolic content of the infusions. Results showed that water with the highest pH (W3; pH = 8.3) and high EC (W3 and W5; EC >10 mS/m) negatively impacted the sensory profile of honeybush tea. Infusions made with W3 and W5 had a 'date pudding' aroma, which was uncharacteristic of honeybush, and lower intensities of typical floral and sweet-associated honeybush aromas. These water samples also led to a salty taste, thick mouthfeel, and much darker color. Additionally, the concentrations of phenolic compounds, such as 3-β-D-glucopyranosyl-4-O-β-D-glucopyranosyliriflophenone, mangiferin, and isomangiferin, were reduced. Infusions prepared with W2, W4, and W6 (pH between 5.3 and 7.8; EC <10 mS/m) showed similar sensory and physicochemical profiles to those prepared with deionized water (pH = 7.1; EC = 0 mS/m). PRACTICAL APPLICATIONS: For the best-tasting honeybush tea, consumers should use water treated by reverse osmosis, with guaranteed low mineral content. This information will help producers and tea merchants present the true flavor of honeybush tea during tastings, supporting effective marketing.

FIGURE 1

Principal component analysis bi‐plot representing the association between selected sensory attributes (attributes where all values <5 were removed) and “cup‐of‐tea” Cyclopia intermedia infusions prepared with water from different sources (n = 6). Sample labels indicate C. intermedia (I) infusion, followed by the water sample used to prepare the infusion (W1–W6), and lastly the C. intermedia sample number (IW1_1 = infusion prepared with W1 and C. intermedia sample 1). A indicates aroma attribute and F indicates flavor attribute. Attributes in bold font are generic honeybush sensory attributes, while those in italic bold font are defining characteristics of the specific species. W1, deionized water; W2, bottled still spring water from Ceres, South Africa; W3, bottled still spring water from Normandien, South Africa; W4, bottled reverse osmosis water from Oasis, Stellenbosch, South Africa; W5, brackish borehole water from a farm in Greyton, South Africa; W6, tap water from Stellenbosch, South Africa.

FIGURE 2

Principal component analysis bi‐plot representing the association between selected sensory attributes (attributes where all values <5 were removed) and "cup‐of‐tea" Cyclopia subternata infusions prepared with water from different sources (n = 6). Sample labels indicate C. subternata (S) infusion, followed by the water sample used to prepare the infusion (W1–W6), and lastly the C. subternata sample number (SW1_1 = infusion prepared with W1 and C. subternata sample 1). A indicates aroma attribute and F indicates flavor attribute. Attributes in bold font are generic honeybush sensory attributes, while those in italic bold font are defining characteristics of the specific species. W1, deionized water; W2, bottled still spring water from Ceres, South Africa; W3, bottled still spring water from Normandien, South Africa; W4, bottled reverse osmosis water from Oasis, Stellenbosch, South Africa; W5, brackish borehole water from a farm in Greyton, South Africa; W6, tap water from Stellenbosch, South Africa.

FIGURE 3

Principal component analysis bi‐plot representing the association between selected sensory attributes (attributes where all values <5 were removed) and "cup‐of‐tea" Cyclopia genistoides infusions prepared with water from different sources (n = 6). Sample labels indicate C. genistoides (G) infusion, followed by the water sample used to prepare the infusion (W1–W6), and lastly the C. genistoides sample number (GW1_1 = infusion prepared with W1 and C. genistoides sample 1). A indicates aroma attribute and F indicates flavor attribute. Attributes in bold font are generic honeybush sensory attributes, while those in italic bold font are defining characteristics of the specific species. W1, deionized water; W2, bottled still spring water from Ceres, South Africa; W3, bottled still spring water from Normandien, South Africa; W4, bottled reverse osmosis water from Oasis, Stellenbosch, South Africa; W5, brackish borehole water from a farm in Greyton, South Africa; W6, tap water from Stellenbosch, South Africa.