“In this study, we reported a randomized placebo-controlled trial to assess the clinical safety and potential efficacy of continuously repeated intake of coffee cherry pulp juice concentrate, a product made from food waste from coffee manufacturing,” wrote researchers from the Institute of Nutrition at Mahidol University in Thailand.
The study, published in the journal Nutrients, was funded by MiVana Coffee, which grows organic Arabica coffee sustainably in the watershed forests of Thailand’s Chiang Rai province and supplied the test products.
Coffee cherry pulp
Coffee pulp, which refers to the skin and the pulp of the coffee fruit, is the main by-product of coffee production and contains an abundance of phytochemicals with antioxidant properties – especially polyphenols, such as chlorogenic acid, caffeine, catechin, epicatechin, chlorogenic acid and rutin.
“These compounds exhibit functional effects, such as lowered cholesterol, improved liver steatosis and reduced hyperlipidemia, as well as antioxidant and anti-inflammation effects, and improved cognitive function,” the study noted.
The researchers refer to a rat study reporting the safety of up to 300 mg of Coffeeberry – an ethanolic extract of the whole coffee fruit, as well as a clinical study in college athletes showing that whole coffee fruit powder at 800 mg per day for 28 days increased antioxidant capacity with no adverse event effects.
“Nevertheless, the safety profile of products from coffee pulp, which is the part that contains the richest levels of phytochemicals, is unknown,” they added. “Since components of coffee pulp, such as caffeine and tannins, or contaminants, such as mycotoxins, can pose a safety concern, it is important to evaluate the long-term safety of coffee pulp products.”
The randomized, double-blind, placebo-controlled trial assigned a total of 61 healthy adults between the ages of 20 and 55 years to either a coffee pulp juice group or a placebo group. Participants consumed the assigned product as a 14-gram sachet, twice daily before breakfast and before bed for 12 weeks. Contents of the coffee cherry pulp sachet were analyzed to control for bioactive and contaminant content.
“Each 14 g sachet contained polyphenols 62.5–69.5 milligram gallic acid equivalents (mg eq GA) with a total antioxidant of 1392.5–1539.5 micromoles of Trolox equivalents (μmoles TE),” the study reported. “Aflatoxin, arsenic, cadmium, lead, mercury and tin were not detected.”
Adverse symptoms, changes in body weight, hematological and biochemical parameters, vital signs, and heart function were evaluated using subject diaries, interviews, blood and urine tests and electrocardiograms throughout the test period and two weeks following study completion.
“The findings of this study suggest that a continuous intake of coffee cherry pulp juice concentrate of 28 g per day over a period of 12 weeks is considered safe for healthy volunteers,” the researchers concluded. “Moreover, it may provide beneficial effects in maintaining fasting plasma glucose and reducing total cholesterol and LDL.”
They added that future studies to explore the efficacy of coffee cherry pulp products should use a dose of up to 28 g per day, particularly for maintaining healthy cholesterol and managing blood sugar.
“Twelve-Week Safety and Potential Lipid Control Efficacy of Coffee Cherry Pulp Juice Concentrate in Healthy Volunteers”
Authors: Numphumg Rungraung et al.