Apple fermented drinks could outshine kombucha with bioactive benefits

Kombucha is a fizzy, tangy drink made by fermenting tea.

However, brewers ferment other plant-based drinks to explore nutritional properties and flavors.

Researchers in ACS Agricultural Science & Technology compared the biochemistry and flavor of kombucha with brews made from apple and passion fruit juices.

They found that the apple beverage contained high levels of bioactive compounds called flavonoids and ranked highly among taste testers, signaling its promise as a kombucha alternative.

Kombucha-like beverages

To make kombucha, brewers ferment sweetened tea with a spongy disk of microbes known as a SCOBY, or symbiotic culture of bacteria and yeast.

The resulting beverage contains beneficial bacteria from the fermentation process and bioactive compounds from the tea, including flavonoids, phenolics, and anthocyanins, which may have antioxidant and anti-inflammatory properties.

Few studies have investigated whether liquids other than tea could be brewed as kombucha-like beverages with boosted antioxidant levels or unique flavors.

So, Socorro Vanesca, Frota Gaban, and coworkers fermented antioxidant-rich apple and passion fruit juices with a SCOBY to find out.

Apple fermentation

After fermenting apple juice, passion fruit juice, and tea in separate jars for ten days at room temperature, the researchers measured the levels of several bioactive compounds in each brew.

The researchers found that apple beverages had the highest levels of flavonoids, followed by kombucha and passion fruit drinks.

The kombucha and apple beverages had comparable levels of phenolic compounds that were higher than those of the passion fruit beverage, and all three brews had similar amounts of anthocyanin, a red-colored antioxidant.

The researchers asked 12 volunteer taste testers to evaluate each beverage’s color, aroma, and flavor.

The taste testers noted an amber color for the apple beverage, yellow for passion fruit, and gold for the kombucha.

The volunteers reported stronger, fruitier aromas for the fermented fruit juices than the tea.

However, the passion fruit drink tasted more bitter than the sweeter apple and tea drinks, which received equal votes as the favorite beverage.

Because fermented apple juice has more flavonoids and a pleasant taste than other beverages, the researchers say it could be a successful alternative to kombucha made from tea.

They plan to explore the health benefits and flavors of other fermented fruits.

Kombucha is a probiotic beverage derived from the fermentation of sweetened Camellia sinensis tea by a SCOBY, typically over 7–10 days at room temperature.

Yellow passion fruit is grown in tropical and subtropical countries. This fruit has been extensively used in traditional medicine as a sedative and anxiolytic agent and is believed to possess antioxidant, anti-inflammatory, gastroprotective, and antidiabetic properties.

The apple is one of the most popular fruits produced worldwide.

Apples’ health benefits, particularly in the prevention of chronic diseases such as cardiovascular diseases, are attributed to their high dietary fiber content and bioactive compounds such as flavan-3-ols, phenolic acids, dihydrochalcones, and flavonols.

This study explored the effects of substituting C. sinensis tea with apples and passion fruit.

It assessed potential physicochemical, proximate, bioactive, and sensory properties’ alterations.

The objective is to develop a product with a bioactive compound content similar to or higher than that found in kombucha and novel sensory characteristics that resonate with potential consumers.