In the present study, combination of infrared (IR) based dry blanching and hybrid drying involving IR‐hot air was used for bitter gourd slices. Infrared blanching conditions were standardized based on the degree of enzyme (peroxidase and polyphenol oxidase) inactivation and product quality. The performance of IR blanching was compared with microwave (MW), water, and steam blanching. The performance of hybrid drying was compared to that of hot air (HA) drying. Microwave and IR blanched slices retained higher amount of ascorbic acid (95% and 93%, respectively) and charantin (76.8% and 74.8%), as compared to water and steam blanching. Infrared blanching followed by hybrid drying required ∼66% lesser time than water blanched‐HA dried with higher retention of charantin (68.4%), ascorbic acid (86.3%), and chlorophyll (42.9%), also consuming 79% less energy than HA drying. The results showed that IR‐based blanching and hybrid drying could be used effectively to produce dried bitter gourd slices having better quality. Practical applications Bitter gourd (Momordica charantia L.) is a good source of ascorbic acid and charantin. This study explored the potentials of infrared assisted blanching and hybrid drying of bitter gourd slices as an alternative to wet blanching (water & steam) and hot air drying. The infrared (IR) assisted blanching and hybrid drying employed in the present study resulted in shorter processing time with higher nutrient retention and higher energy efficiency than HA drying. The results indicated that IR assisted blanching and hybrid drying techniques have great industrial potential to reduce processing time as well as energy, besides producing the better quality product.

Spearmint (Mentha spicata L.) leaves were dried using four different methods, namely, infrared‐hot air (IR‐HA) drying, radiofrequency‐hot air (RF‐HA) drying, low‐humidity air (LHA) drying, and hot air (HA) drying at three different temperatures (30, 40, and 50°C). The effect of the methods on time required for drying, product quality in terms of chlorophyll, total carotenoids, essential oil yield and its composition, color, browning index (BI), and rehydration ratio was evaluated. The IR‐HA hybrid drying at 50°C resulted in faster process with nearly 62% lesser drying time, as compared to HA drying, and also resulted in higher retention of essential oil (85.7%), carvone (79.6%), and lower BI (50.4). The specific energy requirement of IR‐HA hybrid drying reduced by 60% as compared to HA drying at 50°C. The results showed that hybrid drying involving IR could be effectively used to obtain good quality of dried spearmint leaves in a shorter time with better energy efficiency. Practical applications Spearmint is popular for essential oil, and carvone is the major volatile compound present in the oil, giving its characteristic odor. This study explored the effect of drying methods (IR‐HA, RF‐HA hybrid drying, and LHA drying) on drying characteristics, quality of dried spearmint and its comparison with HA drying. The study showed that IR‐HA drying resulted in shorter processing time with a higher yield of essential oil, carvone retention, and energy efficiency than other drying methods. The results indicated that IR‐HA hybrid drying technique could be explored as an alternative to HA drying of heat‐sensitive herbs like spearmint.

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