Development and Quality Evaluation of a Pineapple–Costus afer (Opete) Extract Composite Drink

Abstract

Pineapple is widely used in beverage production because of its desirable sensory characteristics and nutritional value. The incorporation of underutilised plant materials such as Costus afer (Opete) may improve selected nutritional attributes of fruit-based beverages; however, its inclusion can also influence physicochemical properties and sensory acceptability. Information on the quality characteristics of pineapple–Costus afer composite drinks remains limited. This study developed and evaluated composite beverages produced from pineapple juice and Costus afer (Opete) extract at different blending ratios. The study investigated the effect of C. afer incorporation on the physicochemical properties, mineral and vitamin C composition, and sensory acceptability of the beverages. Five formulations were prepared: PCA₀ (commercial fruit juice), PCA₁ (90:10 pineapple:C. afer), PCA₂ (80:20), PCA₃ (70:30) and PCA₄ (60:40). The beverages were evaluated for pH, titratable acidity, total soluble solids, total solids, specific gravity, viscosity and turbidity, while calcium, phosphorus, potassium, sodium, iron, magnesium, zinc and vitamin C were determined using standard analytical procedures. Sensory evaluation was conducted using a 9-point hedonic scale with 30 semi-trained assessors. Increasing C. afer incorporation increased pH from 3.42 in PCA₀ to 3.71 in PCA₄, viscosity from 2.18 to 2.48 mPa·s and turbidity from 8.42 to 54.18 NTU, while titratable acidity decreased from 0.62 to 0.50%, total soluble solids from 12.10 to 10.90 °Brix and total solids from 13.42 to 11.94%. Specific gravity ranged from 1.04 to 1.05. The incorporation of C. afer also influenced the mineral and vitamin C composition of the beverages. Calcium increased from 14.25 mg/100 g in PCA₁ to 15.87 mg/100 g in PCA₄, while vitamin C increased from 20.57 to 36.43 mg/100 g. Sensory evaluation showed that PCA₁ had the highest overall acceptability (6.60), followed by PCA₂ (6.20), whereas PCA₄ recorded the lowest score (4.60). The findings demonstrate that C. afer can be incorporated into pineapple-based beverages to enhance selected nutritional attributes and modify important physicochemical properties. However, excessive incorporation may adversely affect sensory quality. The 90:10 pineapple–C. afer formulation (PCA₁) provided the most favourable overall balance between nutritional enhancement, physicochemical characteristics and consumer acceptability.