Protein is a vital macronutrient that helps in the survival of human beings.

In recent years the consumer’s preference for highly convenient food possessing superior characteristics, high nutritional value with minimum processing, easy to eat, safe, should have a longer shelf life and mouth-watering taste has increased. All these demands of the consumer are impossible to be fulfilled by the existing thermal treatments, which provide food with reduced nutritional and sensory qualities with lesser shelf life. This diverted the attention of food professionals towards non-thermal technologies which are eco-friendly, energy-efficient, and do not process food at a higher temperature for a longer time. As a result, non-thermal technology delivers food with higher nutritional and sensory values and with longer shelf life. Non-thermal treatments are cost-effective technologies that constitute a newer bunch of tools that are developing steadily and are being explored across the globe. This review discusses in brief non-thermal technologies like ultraviolet, pulse electric field, high-pressure processing, ultrasonication, cold plasma, and supercritical carbon dioxide.

Freeze drying has been a very successful technology in the food and pharma industries, particularly owing to the benefits it offers in terms of product quality. It is most recommended for high-value foods and those that contain heat-sensitive ingredients. Over the years, to meet industry requirements, several variants of the freeze-drying technology have been developed, even to meet specific drying applications. The process of freeze-drying is highly energy-intensive and time-consuming. Nevertheless, innovative techniques are available with the potential to produce products at reduced drying times and lower cost, while being environment-friendly and maintaining freeze-dried quality. This review summarizes advances in the application of infrared, microwave, ultrasound, pulsed electric field, and other techniques as pretreatments and/or to assist conventional freeze-drying processes. Freeze drying combined with other techniques can provide more benefits in terms of energy, time, and cost savings. In this review, comparative studies have been presented to describe these aspects. Such techniques to assist the freeze-drying process can be linked well with sustainable food processing strategies, particularly considering a significant reduction in energy requirements.