Carbonation Stability and Sensory Evaluation of Lemon Lime Sparkling Water

🧪 Today's Task

Client: Lemon lime sparkling water
Our role: Carbonation stability and sensory evaluation

Task: Carbonation stability testing and sensory evaluation of a naturally flavoured lemon lime sparkling water.

📍 Lab location: Food Research Lab

Event: Carbonation Stability and Sensory Evaluation of Lemon Lime Sparkling Water

We evaluated two variants of a naturally flavoured lemon lime sparkling water for carbonation stability and sensory quality. I measured CO₂ retention at set intervals over 72 hours, assessed effervescence and fizziness, and ran a structured sensory panel evaluation covering appearance, aroma, taste, flavour-by-mouth, carbonation/texture and aftertaste. The aim was to identify the variant with better carbonation persistence and sensory appeal to take forward to pilot-scale development.

😊 How I Felt Before Starting

Before starting, I anticipated a few project-specific technical challenges. Keeping CO₂ measurement conditions consistent across the 0, 24, 48 and 72-hour intervals was critical, because temperature, handling and sample opening all influence carbonation readings. I planned to standardise sample storage, measurement conditions and handling at every interval.

I also expected only subtle differences in fizziness, citrus aroma and mouthfeel between the variants, so I planned a structured sensory protocol with consistent serving conditions and a 9-point hedonic scale. By comparing the CO₂ data with the sensory scores, I wanted to see whether differences in carbonation retention translated into differences that people could actually perceive.

🧪 What We Did Today?

Product Development Plan

The evaluation compared two lemon lime sparkling water variants, Variant 1 (lower carbonation) and Variant 2 (higher carbonation), for carbonation retention, effervescence and sensory performance. The results were used to decide which variant to take into further development.

Key Steps Followed Today

Phase 1: Carbonation stability and CO₂ retention

I measured CO₂ content immediately after filling and again at 24, 48 and 72 hours using the pressure–temperature method, in which a carbonation tester reads the pressure in the container at a recorded sample temperature and converts it to volumes of CO₂. Retention at each interval is expressed as a percentage of the initial reading, and loss as the remainder.

Phase 2: Effervescence and fizziness assessment

Both variants were served under standardised conditions and assessed for bubble persistence, bubble characteristics, foam/collar formation and perceived fizziness, to compare their carbonation behaviour and sparkling sensation.

Phase 3: Sensory evaluation

A consumer-style acceptability panel scored appearance, aroma, taste, flavour-by-mouth, carbonation/texture and aftertaste on a 9-point hedonic scale (1 = dislike extremely, 9 = like extremely). I then compared the sensory results with the carbonation data to see how carbonation level affected overall product quality.

📚 What I Learned?

Observations & Learnings

• Carbonation retention went hand in hand with perceived freshness, effervescence and mouthfeel; see our explainer on carbonation and perceived fizziness.
• Variant 2 retained more CO₂ (85% at 72 hours) and kept stronger fizziness and mouthfeel than Variant 1 (78%).
• Aroma perception can shift with carbonation level, because CO₂ affects how volatile citrus notes are released and perceived^[1].
• CO₂ readings and panel fizziness scores moved in step: both declined over the 72 hours, and both declined less for Variant 2.

Outcome (Analysis Table)

Table 1. CO₂ retention and perceived fizziness over 72 hours

Table 2. Mean sensory scores (9-point hedonic scale)

Interpretation

The two lemon lime sparkling water variants differed clearly in carbonation stability and sensory performance. Variant 1 (lower carbonation) retained less CO₂ and gave softer effervescence. Variant 2 (higher carbonation) retained more CO₂, held its fizziness for longer and scored higher on every sensory attribute, from appearance and aroma to flavour-by-mouth, carbonation/texture and aftertaste. On the combined evidence of carbonation stability, effervescence and sensory scores, Variant 2 was selected for further product development.

A note on scale: these are 72-hour bench figures that compare the two variants under the same handling. As I noted before starting, handling and sample opening at each interval influence the readings, so the losses are larger than you would expect from a sealed retail pack over three days. Read them as a comparison between V1 and V2, not as a shelf-life prediction.

✅ What Went Well?

• Compared Variant 1 (lower carbonation) and Variant 2 (higher carbonation) at 0, 24, 48 and 72 hours, with a clear difference in carbonation retention.
• Variant 2 retained 85% of its CO₂ at 72 hours, against 78% for Variant 1: losses of 15% and 22% respectively.
• Variant 2 kept stronger effervescence: its fizziness score fell from 8.2 to 7.6, against 8.0 to 6.8 for Variant 1.
• Variant 2 scored higher on all six sensory attributes: appearance, aroma, taste, flavour-by-mouth, carbonation/texture and aftertaste.
• The pattern fits published sensory work showing that carbonation changes how flavour is perceived: CO₂ has been shown to raise perceived aroma intensity in flavoured carbonated drinks^[1] and to suppress perceived sweetness in a carbonated model beverage^[2].
• Variant 2 (higher carbonation) was selected for further development on the strength of its CO₂ retention, effervescence and sensory scores.

⚠️ What Could I Have Done Better?

• Extend carbonation testing to longer storage periods and a range of storage temperatures.
• Report CO₂ as absolute volumes alongside percentage retention, so the starting carbonation of each variant is visible.
• Use a larger sensory panel, and report panel size, for more statistically robust scores.
• Test carbonation retention in sealed packs across different packaging and closure types.
• Add Quantitative Descriptive Analysis (QDA) with a trained panel to profile attribute intensities, alongside the acceptability scores.
• Apply Design of Experiments (DoE) to optimise carbonation level and sensory parameters together for robust scale-up.

For brands & formulators

Developing a flavoured sparkling water or soft drink? FRL’s beverage team runs carbonation-retention trials, packaging and closure checks, and sensory evaluation, with formulations reviewed against the FSSAI standards for water-based beverages. For a related carbonated-drink trial, see our masala soda formulation lab diary.

Talk to our beverage formulation team about your next carbonated product.

1. Saint-Eve, A., Déléris, I., Aubin, E., Semon, E., Feron, G., Rabillier, J.-M., Ibarra, D., Guichard, E., & Souchon, I. (2009). Influence of composition (CO₂ and sugar) on aroma release and perception of mint-flavored carbonated beverages. Journal of Agricultural and Food Chemistry, 57(13), 5891–5898. https://doi.org/10.1021/jf900542j
2. Clark, R. A., Hewson, L., Bealin-Kelly, F., & Hort, J. (2011). The interactions of CO₂, ethanol, hop acids and sweetener on flavour perception in a model beer. Chemosensory Perception, 4(1–2), 42–54. https://doi.org/10.1007/s12078-011-9087-3