Coffee substitutes: A review of the technology, characteristics, application, and future perspective

Despite being one of the most frequently consumed beverages worldwide, there are concerns that excessive consumption of coffee can have adverse effects, especially concerning the addictive and stimulating effects of the alkaloid caffeine, which contributes to coffee's popularity. It is known to increase the risk of hypertension and heart rate among predisposed individuals, adversely affecting the nervous system. Even though they differ in nature from those found in coffee, coffee substitutes can be considered economically and health-wise as a favorable alternative to natural coffee brews. This review summarizes the state-of-the-art varieties of plants used as coffee substitutes and discusses their production technology, chemical composition, nutritional properties, health benefits, economic challenges, and rationale for choosing the plant as a substitute for coffee. Various instant products and coffee substitute blends are also available on the market especially based on different kinds of plants and herbs like ginger, rye, date pits, quinoa, lupine, chicory, barley, rye, oak, and so on. These coffee substitutes have several advantages especially having no caffeine and containing different beneficial phytochemicals, although the results of the difference between the levels of harmful compounds in coffee and coffee substitutes were contradictory. Therefore, it is no wonder that the development of coffee substitutes, which are beverages that are able to mimic the taste and aroma of coffee, is on the rise at present.