Drying as a technique for food preservation has a long history. It remains a very efficient and widely used way to greatly extend the life of foodstuffs. Once safely protected from light and gases, the food retains its nutritional value and texture until re-hydrated. Removing the water eliminates any support for bacteria and other contamination. It also removes a high proportion of the product weight and space requirements, saving valuable resources used in storage and transport.
Aluminium foil can provide the essential barrier needed to stop the ingress of moisture and escape of subtle flavours. It also prevents the UV rays, present in most forms of lighting, from causing ‘photo-oxidation’ and the rancid taste from fat and oil components in dried food products.
Alufoil, mainly in the form of sachets, is widely used to pack such food items as peas, beans, milk and soup powders, cake mixes, sweet and savoury sauces, herbs and spices, yeast, instant beverages such as chocolate and malt-based drinks, tea and coffee. Single serve sachets ensure that the rest of the contents remain in top condition. The sachet or pouch for dried products can be made in a variety of sizes and shapes, from the smallest ‘stickpack’ of instant coffee to very large multi-portion packs used by the catering industry for such products as soup and cake mixes.
In the savoury foods sector there are usually sensitive but essential ingredients upon which the flavour and food value depend. Dry cheese products such as powdered Parmesan, require strictly controlled but low humidity content for long life coupled with good flavour. Meat, fish and poultry stock cubes, often high in moisture-loving salt, receive full (and deadfold) protection from a non-laminated alufoil wrapper.
Many cake mixes, powdered dessert sauces and biscuits are high in sugar, a highly hygroscopic ingredient. The shelf life of biscuits can also suffer if not fully protected from oxygen and moisture. Alufoil laminated pouches and sachets can stop such deterioration.
Sold in single-serve sachets, drinks such as powdered milk and chocolate, malt-based drinks, instant coffee and tea can all benefit from the longevity provided by alufoil helping to make sure that the drink can still be fully enjoyed many months later, even beyond its ‘use by’ date.
For many dry food products several versions of alufoil lined cartons can combine technical efficiency with great consumer convenience and attractive graphic design. Powdered food products such as baby milk and drinks such as chocolate and tea can be effectively packed in foil-lined cartons. Some cylindrical designs offer an easy-open, fully protective alufoil membrane under a plastic reclosable lid. Rectangular cartons can be perforated at the top seam for easy opening.
A fine example of alufoil’s protective role is the packaging of aromatic herbs and spices. Alufoil has been scientifically proven as a complete barrier for the organic molecules which make up flavour and taste. Dried yeast, a ‘living’ organism, will last for very long periods in the total protection from moisture that an alufoil sachet can provide.