Science for product makers: How to perform a cannabis beverage taste evaluation

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In my last post, we discussed how genetics impact the ability to taste, introducing subjectivity and uncertainty to sensory results. We discussed how to address those issues by first identifying super tasters within your team and then appointing a “Golden Tongue” to break ties and make final calls regarding flavor formulation.

After assembling your tasting group, it's important to pay attention to some key details when executing your sensory test. Let’s examine the factors that need to be considered when conducting the test.

Tasting Environment

We often see people taste a sample right from the tank on the production floor. It works for a quick check, but the chaos around you would inevitably impact the decision. It is best to set a designated time and place to bring all tasters together. The room does not need to be fancy; you can use any meeting room with a clean table, but make sure to dedicate the space to your analysis by minimizing distractions. It’s all about psychology! It sends a signal to every taster that it is time to focus. This seemingly easy step is often neglected but is also the foundation to gain high confidence in tasting results.

With more resources, we can improve the tasting room by having uniform lighting to simulate daylight and having an air purifier with a carbon filter to control odor. We can even build individual testing stations to minimize taster interactions, which will be addressed below.

Assign a sensory facilitator to manage testing conditions

Secondly, we need to find a sensory facilitator, whose job is to prepare samples ahead of time, offer samples according to plan, control the pace of tasting, gather results and organize discussion. Essentially, the sensory facilitator’s job is to make sure tasters will not need to worry about any external factors and can just focus on tasting & offering feedback. We need to acknowledge that humans can be very biased and our decisions can be easily influenced by external factors. So, during tasting, it is the sensory facilitator’s job to remove bias and reduce the influences from external factors as much as possible. Below are some key factors to consider:

1. Avoid palate stimulation. Avoid coffee, smoking, spicy food, candy, or any other food with strong flavors for at least 1 hour ahead of the tasting. This offers the highest sensitivity and accuracy.
2. Samples should be blind. Knowing the sample type inevitably creates bias to tasters. I suggest labeling each sample with a random three digit code. When we see sample 259 vs sample 501, our brain automatically puts equal weight on them.
3. Avoid verbal communication among tasters. Humans can easily be influenced by other people’s reactions. “Wow, that tastes terrible” or even a funny facial expression can impact the decision of others. That is why individual testing stations can help. But even without privacy screens, tasters should agree not to share any opinion verbally or physically until the open discussion portion of the analysis.
4. Take notes on paper. A paper / pen to write down conclusions is the best way to keep tasters focused and to record first impressions. Instruct them to immediately write down key words that best describe the sensory notes after each sample.
5. Reset the palate between samples. The best way is to eat an unsalted saltine cracker followed by water to wash the mouth clean. Wait at least 60 seconds for tasters to reset the palate before tasting another sample.
6. Spit samples to minimize psychoactive effects.* In order for the spitting method to be effective, let the sample wet the inner throat. The best way is to begin the swallowing gesture but stop before swallowing. *The spitting method can also deliver certain psychoactive effects from direct absorption through the mucosa system. Check out my previous article addressing this topic.
7. Be aware of sensory fatigue. Intense flavors may linger, causing the palate to take longer to reset. When fatigue happens, it is best to stop and taste another day.
8. Discuss results and reveal sample types only after everyone completes the tasting and records their notes. The sensory facilitator should write the sample number IDs on a whiteboard and ask tasters their opinions of each sample. At this time, tasters can freely express their feedback based on their written key words. Keep in mind, we HAVE NOT revealed the sample types yet. Do not reveal them until after the discussion period has ended to avoid prejudice and bias during discussion.

Following proper scientific protocol is critical to obtaining accurate results

High confidence can be achieved if the sensory evaluation process is done following proper scientific protocol. The role of sensory facilitator is critical: he or she needs to determine the goal of the test and prepare samples ahead of time, control the pace of the sensory process, organize the discussion, and help the group reach a conclusion. The ultimate goal is to remove all the possible subjective influences so tasters can focus and offer the most accurate answers.

Up next: I'll explain how to present the sensory samples and how to analyze the sensory data — stay tuned!

Dr. Harold Han — the “Happy Chemist” — combines his storied background in emulsion chemistry and science with curiosity and fascination in the rapidly growing cannabis industry. Developing nano and micro emulsions his entire career, Harold holds a Ph.D in Surface Chemistry from NYU and is the holder of multiple patents for his inventions in emulsion chemistry.

As the Chief Science Officer at Vertosa, Harold spearheads the company’s development of industry-leading and customized active ingredients for infused product makers, offering pre-suspended aqueous solutions to create incredibly homogenous and stable products while maximizing bioavailability, clarity, and taste.

To learn more about the science of cannabis, make sure to follow Harold on LinkedIn and check out his Happy Chemist videos.