Storage and Aluminum Foil Packaging Dependent Physical Properties of Tomatoes

Tomatoes (Lycopersicon esculentum Mill) and tomato products are an important part of human diet. It is rich source of vitamins A, C, potassium, minerals and fibers. Lycopene is a phytochemical nutrient element found in many fruits and vegetables, but excessively found in tomato that imparts natural red colour [1, 2]. Use of tomatoes is increasing day by day and a variety of products like puree, syrup, paste, ketchup, juice etc. are made. Viswanathan et al. [3] concluded that properties viz., size, density, moisture and force varied with the variety of the tomato fruits. The per cent seed, pulp and skin content in the fruit also varied with the variety. To design and optimization a machine for handling, cleaning, conveying, separation and storing, the physical attributes and their relationships must be known [4]. Designing such equipment without consideration of these properties may yield poor results. Therefore the determination and consideration of these properties have an important role [5]. Among these physical properties, length, width, thickness, mass, volume, projected areas and center of gravity are the most important factors in sizing systems [6]. Varshney et al. [7] studies the physical and mechanical properties of tomato and revealed that moisture content and weight density of fruits decreased while loss and volume shrinkage increased with storage period. TaheriGaravand et al. [5] studied on some morphological and physical characteristics of tomato used in mass models to characterize best post harvesting options. Onifade et al. [8] investigate some physical properties of local variety of tomatoes that are relevant in the handling and processing of the fruits. The primary purpose of a manufacturer is to protect the food products, to keep it in good condition and to preserve under suitable form of packaging for a finished product. As aluminum foil acts as a complete barrier to light and oxygen (which cause fats to oxidize or become rancid), odors and flavors, moisture, and bacteria, it is used extensively in food and pharmaceutical packaging. Aluminum foil is used to make long life packs (aseptic packaging) for drinks and dairy products which enables storage without refrigeration. Foil is a very thin sheet of rolled aluminum. The thickness of foil ranges from the thinnest currently produced commercially at about 0.0065 mm (or 6.5 μm) to the defined upper limit of 0.2 mm (or 200 μm). Standard household foil is typically 0.016 mm thick and heavy duty household foil is typically 0.024 mm thick. Thin foils are fragile and are sometimes laminated to other materials such as plastics or paper to make them more useful.