Basharat Yousuf

Food packaging is essential part of modern food processing. Edible films and coatings have their importance as sustainable and biodegradable alternatives to conventional food packaging. They have been used long ago to perform some primary functions in food preservation, including moisture control, shelf life extension, and sensory enhancement. Various types of materials commonly used in film formulations are polysaccharides, proteins, and lipids. Currently there is increased emphasis on their applications in various food sectors. As a part of the growing trend toward sustainable food systems, edible films and coatings serve not only to preserve the food but also as an alternative to synthetic packaging materials, which often contribute significantly to environmental pollution. However, use and particularly their commercialization is facing challenges and limitations such as physical properties and consumer acceptance, and hence there is a need for deeper innovations and consideration of regulatory aspects.

Application of hydrocolloid based edible coatings is widely investigated as a promising means to retain quality and to extend the shelf life of food products. Present investigation was aimed to analyze influence of treatments, with different concentrations of lemon extract (0, 5, 10 and 15)% and coating with (0 and 5)% soy protein isolate (SPI), on fresh-cut melons. After the treatments, the samples were packed in polypropylene containers and kept at 4 °C for quality and shelf life analyses. The study involved 8 combinations of melon samples which were monitored in triplicate on specific days for different quality parameters including headspace gases, physicochemical, sensory and microbiological changes over the storage period. Lowest weight loss was indicated by samples treated with both lemon extract and soy protein isolate. When compared to control, coated samples indicated 4.36 log CFU/g lesser total plate count, and 2.39 log CFU/g lesser yeast and mold count at the completion of storage. Treatments showed effectiveness to retain vitamin C of melon samples. Total soluble solids, pH and titratable acidity varied remarkably through the storage life. Significant differences were observed in sensory attributes of control and coated samples. Chroma and color change (ΔE) values also reflected the potential of soy protein isolate coating to protect foods. Overall, the results suggested that lemon extract and soy protein isolate can help in retaining quality and extending the shelf life of fresh-cut melon.

Dehydration of foods is not simply a preservation technique in the present era, rather an important food processing operation which has many benefits in addition to enhancement of shelf life of foods. There are various methods of drying foods and most of them are unique in their own way. Liquid foods can be dried in many ways and foam mat drying is one such method which is being researched frequently for its potential use at commercial level. Foam mat drying has got almost all the features to be a commercially successful method of drying. It is a simple technique and has shown good results in drying of liquid foods with low glass transition temperature. Hybridization of this method has shown the results that make this technology look even more promising than the conventional one. Studies on freeze drying, vacuum drying and microwave drying of foam have indicated encouraging results with respect to drying kinetics and product quality. This review presents an overview of foam mat drying of foods. The procedure and technology of this method of drying have been summarized with an intention to make them easy to understand. The emphasis is, however, on the hybrid foam mat drying technology.