What Flavor is Most Effective in Masking a Bitter Taste?
Many Active Pharmaceutical Ingredients (APIs) are bitter, some extremely so. Often a formulator’s first reaction to taste masking is to add a “flavor” to the formulation to mask the bitterness. This approach to taste making is not usually successful because of differences in the physiology of taste and smell.
Myth Busted: Taste and Smell are NOT the Same
One of the great myths of taste masking is that taste and smell are the same. We are routinely asked: “Which flavor – orange, grape, chocolate, or mint – is most effective in masking a bitter taste?”
The answer is none.
The difficulty in formulating a palatable drug product typically stems from the taste of the API, which is often strongly bitter or excessively sour or salty.
As we discussed in our first post, “taste” refers to those sensations perceived through the stimulation of the receptor cells located in the taste buds on the epithelium of the tongue and oral cavity. There are five tastes perceived in the oral cavity – sweet, sour salty, bitter and umami. These are known as the basic tastes.
“Flavors” are aroma chemicals that are perceived via the sense of smell (olfaction) through stimulation of receptor cells in the olfactory epithelium located in the upper reaches of the nasal cavity. It’s been calculated that humans are able differentiate a trillion individual smells.
Thus taste and smell represent completely different modalities, just like the sense of sight is different than touch. And they have no impact on one another. In this way, commercial flavoring aromatics – such as orange, grape, chocolate, or mint (smell/ olfaction) – cannot mask bitterness (taste).
Up Next: The Nomenclature of Flavors
In future posts I’ll be discussing what every pharmaceutical formulation scientist needs to know about flavors – their nomenclature
Taste Masking Challenge? Senopsys Can Help!
Are you faced with the need to develop a palatable drug product to support clinical trials or commercial development? Our scientists are expert in both taste assessment and taste masking.
We use our experienced GCP-compliant taste panels and analytic tools to quantify the taste masking challenge and guide formulation development. And we apply a structured, sensory-directed development approach pioneered in the food industry to create palatable, taste-masked drug formulations for liquids, powders and solids.
I am the caregiver for my mom who is 93 y old and has severe dementia, she does not sleep well. I was giving her a Tylenol pm but she is now unable to swallow it whole. I have crushed it but am not able to find the food that will mask its bitterness. Can you help…. very tired:)
If you can mix it with a half glass of milk or milk substitute and some chocolate syrup, it will go a long way towards making it palatable. I used Olivia brand organic chocolate syrup and it worked, brilliantly. I don’t know how well Tylenol dissolves in water, so I would suggest crushing it as finely as possible and mixing and drinking quickly, if needed. It’s possible that plain old Hershey’s syrup will work, but I haven’t tried it.
Thank you Dale,
We haven’t tried Olivia experimentally, but other brands of chocolate syrup are able to mitigate some aversive sensory attributes well. Importantly, you should try to follow up the dose with a little more of the same product without drug. It helps shorten the aftertaste.
Hi! I’m trying to mask the flavor of peanut powder. Any suggestions on what I can use so the taste won’t be so strong?
Thank you!!
Thanks Adriana,
This is an interesting question, but first I have to ask what you mean by “flavor”. To a sensory scientist, “Flavor” includes both volatile aroma compounds, perceived by your sense of smell (also known as olfaction), and compounds that elicit a “basic taste” response (e.g. sweet, soul, salty and bitter”). https://www.senopsys.com/taste-masking-blog/definitions-of-flavor-implications-on-taste-masking/
Peanut powder has both a bitter taste and characteristic aromatics. To improve the bitter taste challenge, you will need to blend the formula with other basic tastes (sweet, sour, salty, and umami), and possibly taste modifiers to reduce the perception. Success here is achieved via the psychophysical principle of “mixture suppression” also known as “taste-taste interaction”, which is a fundamental concept in the formulation of commercial food products, whereby combinations of basic tastes are perceived as less intense than their individual constituents.
Moving on to the aroma challenge of peanuts. Peanut aroma is somewhat bland in raw peanuts, and mostly generated the roasting process.
Roasted peanuts contain large amounts of pyrazines, with some furanones and disulfides (https://www.ncbi.nlm.nih.gov/pubmed/23832337). Ideally you are going to want to complement this aroma with other pyrazine-containing food products: Coffee, Chocolate, Caramel come to mind. Also, you should look into the possibility of taking this formula to the savory side. Some of the above flavor compounds are present in roasted meat, and it’s no coincidence that’s why you see peanuts as ingredients in asian savory dishes and stews.
David
Hello David- I am experiencing a great degree of difficulty reaching a comfortable taste while combining terpenes, CBD, and honey. I have tested a number of terpene flavors. So far, Thin Mint Cookies and Blueberry are the most pleasant. The biggest setback is masking a lingering bitter after taste. Would you mind sharing your insight on how I might achieve a round effect on the scent and flavor palet?
Berberine HCL. That’s all lol. ANY advice would be greatly appreciated.
Caffeine. What is the secret to getting rid of the flavor of caffeine isolate?
Caffeine has a strong bitter basic taste. The secret is to find complementary basic tastes that balance the perceived bitterness initially and throughout the aftertaste. Luckily, caffeine is short lived, so a sweetener and sour system that fade quickly in the aftertaste would fit the bill. These may include sugar alcohols, bulk nutritive sweeteners (fructose, glucose, or sucrose), acesulfame potassium, or fumaric acid – all of which decay quickly and avoid a long cloying flavor profile.
Hi.
So when part of my guava tree broke with hundreds of unripe tiny guavas, I hoped cooking them would make a palatable squash, jam preserve or some food item. I boiled the with sugar and blended it. But there is a horrific bitter after taste. Now I have a ton of this bitter tasting paste and no idea of a use for it.
My initial idea was to make a guava drink with salt and sugar. But the bitterness is over powering.
Yuck, what a waste. You should focus on recipes that are able to blend all the basic tastes together to suppress the offending bitterness. In the sensory literature, this is called “Taste/Taste interaction” or “Mixture suppression”. How about trying a chutney with sweet onions, sour tamarind, on a umami rich protein like duck?
hello, i am working on formulation in that API itself has bitter taste.Could you please suggest some flavoring agent rather than sweetener to mask it plus should not have bitter after taste effect?
Hello Namrata,
Thank you for your comment. It’s possible that your API is bitter as are so many drug actives – but it could also produce trigeminal irritation, e.g., numbing, which could be by design for this indication.
https://www.senopsys.com/taste-masking-blog/taste-masking-theres-beneath-hood-bitterness/
Assuming it is bitter, that’s what’s called a basic taste (along with sweet, sour, salty and umami) and is perceived by taste receptors on the tongue. “Flavors” are aroma chemicals that are perceived by olfaction and play no role in masking a bitter (or other) basic taste:
https://www.senopsys.com/taste-masking-blog/definitions-of-flavor-implications-on-taste-masking/
With this as background, the issue may have less to do with the flavors under consideration but the underlying formulation. The only way to know would be to evaluate an unsweetened/unflavored dosage to ascertain taste making effectiveness.