Infrared drying of herbs (Research Note)

Abstract

Drying experiments on peppermint (Mentha piperita L.), anise hyssop (Agastache foeniculum L.), parsley (Petroselinum crispum L.) and garden angelica (Angelica archangelica L.) were conducted using near infrared drying, operating at a product temperature of 35-50°C. The oil content, composition and residual water content of the dried herbs were determined. The microbiological quality of the fresh and the dried material was determined for total bacterial count and coliforms, moulds and yeasts. The results indicate that infrared radiation is has potential for drying herbs since it is gentle and shortens the processing time.