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Moisture content of food material is a key factor influencing the quality of storage and extending the quality of a food product. Manufacturers develop new technologies to process sensitive food materials to supply new products with improved properties and high quality. The process in which the air is cooled sensibly while the moisture is removed from food is called cooling with dehumidification process. The system fundamentally acts as a heat pump, which pumps the heat from the dehumidified air to a different air stream in another area, with the aid of a refrigerant gas to carry the heat. This article reviews the potential of low-temperature heat pump dehumidifier drying used in the food industry. Moreover, this describes the principle of cooling with dehumidification (CWD) process, the importance of studying psychrometric charts to understand CWD process, measures used in identify energy efficiency, comparison of this method over common dryers, applications, advantages and limitations of the CWD drying method. Practical applications Multiple measures have been taken to increase the drying efficiency of convection drying, especially by the application of cooling with dehumidified techniques. This drying technique has comparably higher energy efficiency, better and consistent product quality and the ability to control drying temperature and humidity over other conventional methods. Low-temperature heat pump dryers are used increasingly applications in the food industry for the drying of grains, fruits, vegetables, herbs, spices, fish, meat, pet foods, and other heat-sensitive food products in several countries. 1 | INTRODUCTION Drying is a unit operation that has been applied in different industries including food industry since ancient times (Hall, 2007; Hepbasli, Colak, Hancioglu, Icier, & Erbay, 2010). Drying preserves the product by removing some amount of water in the material, while freezing reduces its temperature below the freezing point of water. There are three ways to eliminate moisture from the air: by cooling it to condense water vapor, by increasing the total pressure which leads condensation and passing the air over a desiccant, which pulls moisture from the air through differences in vapor pressures (Dai

The study was aimed to evaluate how drying methods and extracting solvents can preserve antimicrobial properties of Acmella flower pods. Four drying techniques (sun drying [SD], air drying [AD], oven drying [OD], and cooling with dehumidifying [CWD]) and three different solvent extractions (ethanol extracts [EE], water extracts [WE], and pet ether extracts [PEE]) were employed to evaluate extraction yield (EY), phytochemical analysis, and in vitro antibacterial activity. The highest EY was observed in CWD dried WE. Alkaloids, tannin, and quinone were detected in all extracts while flavonoid only in SD and CWD dried EE. CWD dried WE comprised all tested phytochemicals, except flavonoids. CWD dried WE showed higher zones of inhibitions (ZOI) 18.8, 14.0, 12.0, 20.2, and 17.3 mm for Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans, respectively. CWD dried pod extracts showed higher effectivity against bacteria and fungus while lowest given by SD extracts. CWD dried WE gave 20 volatile compounds in GC‐MS, including dilauryl thiodipropionate, clionasterol, and spilanthol. Practical applications This study provided a comprehensive evaluation of how the drying method and solvent used for extraction of Acmella oleracea flower pods can effect on the extraction yield, available phytoconstituents, and antimicrobial activity. Through this study, it was recognized that CWD drying followed by water extraction is the best method to preserve antimicrobial potential and bioactive constituents in preserving raw Acmella oleracea flower pods. Phytochemical availability and ability to inhibit Gram‐negative, positive bacteria, and fungus is an indication of Acmella flower pods' antimicrobial potential which can be employed to control food pathogenic microorganisms in food industry.

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Regular use of petroleum-based plastic packaging films has led to environmental impact due to their total non-biodegradability. Substantially, the food industry generates waste and agricultural-based raw materials have recently been applied to produce biodegradable, renewable and safe to eat packaging materials as a viable alternative to aforesaid dire consequences. Agro packaging concept has emerged where valuable compounds from by-products such as proteins are extracted from animal or plant sources to produce biofilms. Proteins are generally superior to the qualities of other biological compounds available in agricultural by-products. Their ability to form films with better mechanical and barrier properties has been studied and researches are in the process of exploring novel technologies in developing sustainable food packaging materials that are edible and active. This review explores possible applications of animal and plant protein sources from the agricultural by-products in bio-based film production and the inherited properties of these films. Moreover, selected animal by-product proteins such as collagen, gelatin, casein, myofibrillar proteins, keratin as well as plant by-product proteins including soy protein, wheat gluten, corn-zein, canola protein are discussed in details with special reference to available redundant protein types, technologies applied to obtain films, mechanical properties, functions of films and their applications.