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Describe the raw materials or food products that are suitable for each type of cans.

1. Lacquer CansLacquers are widely used to protect metal packaging from corrosion. The coatings formed upondrying of canning lacquers must be able to withstand the conditions under which canned foods aresterilized (about 120C) and be resistant to the long-term action of protein and acid mediums, andthey must not contain substances harmful to health or that change the appearance, smell, or color ofthe food product. These requirements are best met by coatings of lacquers based on synthetic resins.Therefore , the type of foo d prod uc ts i s d ependent on the type of lacque r s used .

Table 1: Metal Can Lacquers and their typical usesResin Sulfide Stain Resistance Typical UsesOleo- resinous Poor Acid FruitsSulfur resistant oleo resinous(added zinc oxide)

Good Vegetables and Soups

Phenolic Very good Meat, fish, soups & VegetablesEpoxy-phenolics Poor Meat, fish, soups, vegetables,

beer, beverages (top coat)Epoxy- phenolics with zincoxide

Good Vegetables & Soups

Aluminized epoxy-phenolics Very good Meat ProductsVinyl Solution N/A Beers & BeveragesAcrylic Very good (pigmented) Vegetables, Soups & prepared

foods containing sulfide stainersPolybutadiene Very good (if zinc) Beer and beverage (1 st coat).

Vegetables and soups if withZnO.

2. Tin-plated (ETP)cans

Tin plated in sufficient thickness, provides good corrosion-resisting properties to steel, and issuitable for direct contact with many products. For instance (uncoated):

White Fruits : Peaches, apricots, pineapple and pearsTomato based products : Tomatoes in brine, beans in tomato sauce, tomato puree & tomato paste.Vegetable products : Mushrooms & AsparagusAcidic Food Products : Desirable as it eliminates oxygen but it causes discoloration of the contents.Clear Juices : Pears, peaches, pineapples and yellow lumps.Oils : Vegetable oils (large catering tins)Dry foods : Milk powder, instant baby food, sweets, roasted nuts, biscuits, teas and etc.

3. Tin-Free Steel (TFS) cansSometime referred as electrolytic chromium coated steel, is created by electrolytically coating blackplate with a thin layer of chrome oxide. TFS food can ends need both internal and external coatingsfor protection. The function of a chromium coating is to prevent atmospheric oxidation or sulphurstaining of the steel by foodstuffs and to improve lacquer adhesion. Thus, the internal type oflacquer (Table 1) used determines the type of food products suitable. One example of TFS cans withcoating:

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