Herbal infusion – processing techniques, bioactivity, quality, and safety

Abstract

Botanical remedy, including herbal infusion or tisane, is getting attention from the healthconscious consumer to provide dietary polyphenol/dietary antioxidants. However, some quality and pharmacological aspects of dried herbs used in the tisane or herbal tea are taken for granted and can place the consumer's health and safety at risk. The purpose of this review is to investigate pre-harvesting and post-harvesting aspects of herbal tea that implicate the quality, i.e., therapeutic properties and safety, i.e., toxicity. Selection of botanical origin, agricultural practice, and pharmacological background (pharmacodynamic and pharmacokinetic aspects) of botanical material are the identified vital factors in the pre-harvesting aspects that should be considered before introducing the monoherbal or polyherbal preparation to ensure optimum benefits and safety. Besides the herbal blending preparation, the tea processing standard and drying technique are vital in ensuring the stability of herbal tea and consequently determining the quality of herbal infusion. The variation of processing techniques used and the pharmacological factors of herbal sources have laced on the quality and authenticity issues of herbal infusion and still need further studies to identify the potential health risks to the consumer.