Sensory characterization of bowel cleansing solutions

Table 1 Terms used in the descriptive analysis of the bowel cleansing laxative solutions

Attribute	Definition as worded on score sheet	Anchor words (low to high)
Appearance
Turbidity	The level of haze present in sample when holding the sample at eye level1	Clear to turbid
Viscosity	The resistance to flow when swirling the sample in the cup2	Thin to thick
Odor
Orange	Odor of orange juice3	Not at all to very
Citrus	Odor of lemonade4	Not at all to very
Flavor
Saltiness	Taste elicited by table salt	Not at all to very
Sweetness	Taste elicited by sugar (sucrose)	Not at all to very
Sourness	Taste elicited by citric acid	Not at all to very
Sweetener	Taste elicited by the sweetener solution5	Not at all to very
Bitterness	Taste elicited by caffeine6	Not at all to very
Orange	Flavor of orange juice3	Not at all to very
Citrus	Flavor of lemonade4	Not at all to very
Mouthfeel		Not at all to very
Adhesiveness	The level of cling to surface of tongue when swirling sample in mouth	Not at all to very
Astringency	Dryness and puckering on tongue and palate6	Not at all to very
Mouthcoating	Layer of sample left on palate after swallowing	Not at all to very
Aftertaste		Not at all to very
Sweet	Aftertaste elicited by sugar solution	Not at all to very
Sour	Aftertaste elicited by citric acid solution	Not at all to very
Astringent	Dryness and puckering on tongue and palate after swallowing7	Not at all to very
Bitter	Aftertaste elicited by caffeine solution6	Not at all to very
Throatburn	Burn in throat after swallowing sample7	Not at all to very

¹Mineral water (low level), Rim, bottled at source by Rim Natural Spring Mineral Water SAL - Mount Sannine, Lebanon;

²Mineral water, Rim, bottled at source by Rim Natural Spring Mineral Water SAL - Mount Sannine, Lebanon, for low level vs pineapple juice, Tropicana, bottled by société moderne Libanaise pour le commerce SAL, Beirut, Lebanon, for high level;

³Orange juice (high level), Mr. Juicy, bottled by société moderne Libanaise pour le commerce SAL, Beirut, Lebanon;

⁴Lemonade (high level), Balkis, Balkis SAL, Beirut, Lebanon;

⁵Sweetener solution (high level), prepared by dissolving 2 tea spoons artificial sweetener (Sweet n low, Dietary foods, Soham Cambs, United Kingdom) in 500 mL mineral water;

⁶Cold tea (high level), prepared by soaking 2 bags of black tea (Lipton, Unilever Mashreq tea company, New Borj El Arab, Alexandria, Egypt) in 500 mL hot mineral water, then cooled down to room temperature;

⁷Baking soda solution (high level), prepared by dissolving 2 tea spoons of baking soda (Arm and Hammer, Harrison Street, Princeton New Jersey, United States) in 500 mL of mineral water.

Table 2 Significance of effects (F and P-values) for descriptive attributes for the bowel cleansing laxative solutions

Attributes	Panelist (df = 13)	Sample1 (df = 3)	Replicate (df = 2)	S × P (df = 39)	R × P (df = 26)	S × R (df = 6)
Appearance
Turbidity	5.6d	9.1d	3.1	1.4	1.5	0.5
Viscosity	5.4d	4.2a	4.5a	1.5	1.7a	0.1
Odor
Orange	2.0	15.9d	0.0	2.3b	0.4	1.3
Citrus	2.0	35.0d	4.7a	2.1b	0.6	1.3
Flavor
Saltiness	2.9b	8.8d	0.7	2.7d	1.3	0.9
Sweetness	6.3d	2.8	5.3a	5.7d	1.2	0.8
Sourness	4.5d	18.5d	0.6	2.5d	1.2	1.4
Sweetener	8.4d	3.7a	3.5a	4.7d	1.6	1.6
Bitterness	2.0	8.5d	0.2	4.8d	1.0	0.9
Orange	1.6	10.9d	0.7	6.1d	1.4	0.6
Citrus	1.3	11.4d	2.3	3.7d	1.2	0.7
Mouthfeel
Adhesiveness	4.8d	4.3b	1.3	3.9d	2.0a	1.4
Astringency	2.2a	11.0d	1.2	2.0b	2.6b	0.1
Mouthcoating	3.7d	4.8b	0.9	2.4d	1.6	0.7
Aftertaste
Sweet	10.2d	8.6d	2.6	1.8a	2.4d	1.6
Sour	6.3d	16.3d	2.1	2.4d	0.9	0.8
Astringent	1.3	9.1d	2.1	2.4d	2.1b	0.9
Bitter	2.0	15.2d	0.3	2.2d	1.5	0.7
Throatburn	3.5b	7.9d	0.9	1.9b	1.4	0.4

¹Bowel cleansing laxative solutions. P > 0.05 not significant (no superscript) vs

^aP < 0.05;

^bP < 0.01;

^dP < 0.001.

Table 3 Least squares means of descriptive sensory attributes (rated on a 15 cm line scale) for the bowel cleansing laxative solutions

Attribute	Bowel cleansing laxative solution
	PEG-Asc (mean ± SD)	PEG (mean ± SD)	SPS (mean ± SD)	OSS (mean ± SD)
Appearance
Turbidity	3.5 ± 2.3c	2.9 ± 1.8c	4.5 ± 2.4a	2.8 ± 1.6c
Viscosity	4.1 ± 2.7c	3.5 ± 2.0c	5.0 ± 2.8a	3.8 ± 2.3c
Odor
Orange	3.1 ± 3.1c	1.6 ± 0.4e	5.8 ± 3.4a	1.9 ± 1.4e
Citrus	7.3 ± 3.7a	1.5 ± 0.4e	3.0 ± 2.3c	2.2 ± 1.8ce
Flavor
Saltiness	6.0 ± 3.1a	5.8 ± 3.2a	2.8 ± 1.9c	5.8 ± 3.4a
Sweetness	3.8 ± 2.4	3.0 ± 1.9	4.1 ± 2.6	4.7 ± 3.4
Sourness	6.6 ± 3.0a	2.5 ± 1.4c	6.5 ± 3.2a	6.9 ± 3.8a
Sweetener	4.7 ± 3.5c	3.5 ± 2.5e	4.7 ± 3.4c	5.6 ± 3.3a
Bitterness	2.9 ± 1.9ce	2.2 ± 1.7e	3.2 ± 2.1c	6.0 ± 4.2a
Orange	3.2 ± 3.3c	1.8 ± 0.9e	6.3 ± 4.1a	2.1 ± 2.0e
Citrus	6.6 ± 3.9a	1.9 ± 1.3e	3.2 ± 2.6c	3.0 ± 3.2ce
Mouthfeel
Adhesiveness	5.1 ± 2.6a	3.7 ± 1.9c	4.3 ± 2.2c	5.4 ± 2.6a
Astringency	4.4 ± 2.6c	2.8 ± 2.0e	4.5 ± 2.2c	6.1 ± 3.4a
Mouthcoating	4.7 ± 2.8c	3.8 ± 2.3c	4.3 ± 2.5c	6.0 ± 3.2a
Aftertaste
Sweet	4.7 ± 3.2ac	3.3 ± 2.3e	4.5 ± 3.3c	5.5 ± 3.3a
Sour	5.1 ± 2.6a	2.2 ± 1.4c	5.9 ± 3.1a	6.1 ± 3.9a
Astringent	4.0 ± 2.2c	2.6 ± 1.5e	4.6 ± 2.6c	5.9 ± 3.5a
Bitter	2.4 ± 1.4c	2.2 ± 1.7c	2.8 ± 1.6c	5.5 ± 3.7a
Throatburn	3.5 ± 2.5ce	2.8 ± 2.1e	4.4 ± 2.8c	5.7 ± 3.8a

^aMeans within each row with different superscripts are significantly different (P < 0.05).

^cMeans within each row with different superscripts are significantly different (P < 0.05).

^eMeans within each row with different superscripts are significantly different (P < 0.05).

PEG: Polyethylene glycol; PEG-Asc: PEG + ascorbic acid; SPS: Sodium picosulfate; OSS: Oral sodium sulfate.

Table 4 Significance of effects (F and P-values) for acceptability attributes for the bowel cleansing solutions

Attributes	Panelist (df = 79)	Sample1 (df = 3)
Overall Acceptability	1.8d	22.3d
Odor	1.3	4.2b
Taste	1.6b	22.2d
Mouthfeel	1.9d	14.5d

¹Bowel cleansing laxative solutions. P > 0.05 not significant (no superscript) vs^aP < 0.05;

^bP < 0.01;

^dP < 0.001.

Table 5 Least squares means of acceptability variables (rated using the 9-point hedonic scale) for the bowel cleansing laxative solutions

Acceptability variable	Bowel cleansing laxative solution
	PEG-Asc (mean ± SD)	PEG (mean ± SD)	SPS (mean ± SD)	OSS (mean ± SD)
Overall acceptability	3.8 ± 2.1c	3.1 ± 1.6c	5.5 ± 2.1a	3.8 ± 2.4c
Odor	5.5 ± 2.1ac	4.9 ± 0.9c	5.9 ± 1.8a	5.5 ± 2.5ac
Taste	3.5 ± 2.1c	2.9 ± 1.6c	5.1 ± 2.3a	3.1 ± 2.2c
Mouthfeel	4.2 ± 1.9c	3.8 ± 1.7ce	5.1 ± 2.0a	3.4 ± 2.0e

^aMeans within each row with different superscripts are significantly different (P < 0.05).

^cMeans within each row with different superscripts are significantly different (P < 0.05).

^eMeans within each row with different superscripts are significantly different (P < 0.05).

PEG: Polyethylene glycol; PEG-Asc: PEG + ascorbic acid; SPS: Sodium picosulfate; OSS: Oral sodium sulfate.

Table 6 Percentage of participants’ responses to the additional flavor perceived in the different bowel cleansing laxative solutions

Flavor	Bowel cleansing laxative solution
	PEG-Asc	PEG	SPS	OSS
None	60%	100%	56%	55%
Lemon	28%	0%	13%	1%
Orange	6%	0%	28%	1%
Strawberry	1%	0%	0%	13%
Bubble gum	0%	0%	0%	9%
Cherry	0%	0%	0%	5%
Medicinal	0%	0%	0%	10%
Mint	0%	0%	0%	1%
Green tea	1%	0%	0%	0%
Fruity	3%	0%	4%	4%
Pomegranate	1%	0%	0%	1%

PEG: Polyethylene glycol; PEG-Asc: PEG + ascorbic acid; SPS: Sodium picosulfate; OSS: Oral sodium sulfate.