Asian Food Science Journal

Aims: To formulate a Garcinia atroviridis (Asam gelugur) beverage concentrate with enhanced sensory acceptability and high hydroxycitric acid (HCA) content by balancing fruit acidity with young leaf extract, and to evaluate its nutritional composition and shelf-life stability.

Study Design: A three-factor D-optimal mixture design was used to optimize the proportions of fruit juice, young leaf extract, and fructooligosaccharides (FOS). Sensory acceptance (7-point hedonic), viscosity, and HCA content were modeled. The optimized formulation was characterized for nutritional and physicochemical properties. An accelerated storage study assessed product stability.

Place and Duration of Study: Raw materials were sourced from Johor, Malaysia; laboratory work was conducted at Food Science and Technology Research Center MARDI from August 2022 to December 2023.

Methodology: A D-optimal mixture design (16 runs) used fruit juice (10–20% v/v), young leaf extract (50–70% v/v, 1:5 w/w), and FOS (5–10% w/v) as variables. Responses were HCA content, overall hedonic score, and viscosity. The optimized concentrate was pasteurized, packaged, and its composition analyzed by standard methods. Shelf-life was evaluated at 40°C, 75% RH, for 4 weeks (~2 years ambient).

Results: The optimized concentrate contained 62.7% fruit juice, 19.1% young leaf extract, and 10.0% FOS with high sensory acceptance (~5.5/7), viscosity score (~5.9/7), and HCA (~170.0 mg/100 mL). The product had pH ~2.00, 14.2°Brix, was fat-free (<0.1 g/100 mL), and contained ~13.1 g/100 mL sugars. No microbial growth (<10 CFU/mL) occurred during storage. Minimal changes occurred in pH (1.93–2.00), °Brix (13.8–14.5), viscosity (17.6–24.4 mPa·s), and color brightness (L ~24). Sensory scores remained moderately liked (P=.05).

Conclusion: A G. atroviridis concentrate with optimized fruit, leaf extract, and FOS proportions was developed. The fat-free, HCA-rich product suggests potential weight-management benefits. It maintained its sensory acceptance and microbiological safety after 4 weeks of accelerated storage (~2 years ambient) without preservatives. This demonstrates the feasibility of formulating an acidic fruit concentrate with enhanced health attributes while maintaining consumer acceptability.