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Potato flakes

Introduction

Potato flakes are a dehydrated potato product made primarily from cooked and mashed potatoes. During conventional production, potato mash is spread in a thin layer over heated drum dryers. The dried sheet is then removed and broken into flakes. The product can be rehydrated with water or other liquids and is commonly used in instant mashed potatoes and processed foods.

Potato flakes are one of several forms of dehydrated potato products. Other forms include potato granules, dried slices, dices and potato flour. Potato flakes and potato granules may be used for some similar purposes, but they differ in particle form, structure and manufacturing method.

Production

Commercial production generally begins with washing, peeling and trimming whole potatoes. The potatoes may then be cut, blanched or precooked, cooled and cooked until they are soft enough to be mashed.

The cooked potatoes are mashed or riced to form a relatively uniform potato mash. Processing conditions may be adjusted to influence the texture, colour and rehydration properties of the final product. Depending on the applicable food regulations and production method, permitted ingredients or processing aids may also be used.

The mash is applied in a thin layer to the surface of one or more heated rotating drums. Moisture evaporates rapidly, leaving a dry sheet of potato solids. This sheet is removed from the drum and reduced to flakes of the required size.

Official United States procurement specifications recognise flakes and granules as forms of dehydrated potato products. These specifications also describe processing steps such as washing, steam peeling, cutting, cooking and dehydration.

Physical and functional properties

During cooking, starch within the potato cells gelatinises. Further structural changes occur during drum drying. When the flakes are later mixed with water, the gelatinised starch absorbs moisture and contributes to the viscosity and texture of the reconstituted product.

The functional properties of potato flakes depend on several factors, including:

• potato variety;
• dry-matter content;
• cooking conditions;
• degree of cell damage;
• drum-drying conditions;
• flake size;
• formulation; and
• storage conditions.

Excessive mechanical treatment may damage potato cells and release more starch. This can produce an excessively sticky or pasty texture after rehydration.

Potato flakes are usually cream-coloured or pale yellow. Their colour may vary according to the potato variety, processing conditions and permitted ingredients. Their flavour is generally associated with cooked potatoes, although storage conditions may affect flavour and colour over time.

Uses

The most widely recognised use of potato flakes is the preparation of instant mashed potatoes. The flakes are rehydrated with hot water or another liquid and may be mixed with milk, fat, salt or seasonings.

Potato flakes are also used in fabricated potato snacks made from potato-based dough. In these products, the flakes provide potato solids and may contribute to dough formation, texture and flavour. The Food and Agriculture Organization has identified mashed-potato products and snack foods among the uses of potato flakes.

Other reported applications include:

• soups and sauces;
• bakery products;
• fillings;
• coatings;
• prepared meals;
• formed potato products; and
• some meat-based or plant-based formulations.

Their function varies according to the formulation. They may contribute water absorption, thickening, binding, solids content, texture or potato flavour.

Potato granules

Potato granules are also made from cooked and dehydrated potatoes. However, their finished structure consists of small granular particles rather than thin flakes. Differences in particle structure and cell condition can influence rehydration, texture and handling.

Both flakes and granules are recognised as forms of dehydrated instant mashed potato products in United States Department of Agriculture specifications.

Potato starch

Potato flakes should not be confused with potato starch. Potato flakes retain a broad range of potato solids, while potato starch consists mainly of starch separated from potato tissue.

Because their compositions differ, potato flakes and potato starch generally perform different functions in food formulations.

Potato flour

The expression potato flour is not used consistently in every market. It may refer to flour produced from dried whole potato material, but it is sometimes confused with potato starch in commercial or culinary use.

For this reason, technical specifications and ingredient declarations are important when distinguishing potato flakes, potato flour and potato starch.

Storage

Potato flakes readily absorb moisture from the surrounding environment. They are therefore generally stored in sealed packaging under cool and dry conditions.

Moisture absorption may cause caking and may alter rehydration behaviour. Exposure to heat, oxygen or light may also contribute to changes in flavour, colour and general product quality.

Shelf life is not identical for all potato flakes. It depends on factors such as:

• moisture content;
• formulation;
• packaging material;
• oxygen exposure;
• storage temperature; and
• storage humidity.

For this reason, shelf-life information is normally established for a specific product and packaging system rather than treated as a universal property.

Food regulation

In the Codex Alimentarius food-category system, dried potato flakes are included as an example within the category of dried vegetables, roots and tubers.

Requirements for additives, contaminants, labelling, microbiological criteria and processing aids vary among jurisdictions. Food manufacturers and suppliers are therefore required to follow the regulations applicable in the country of production and the country in which the product is sold.

See also

• Instant mashed potatoes
• Dehydrated food
• Drum drying
• Potato granules
• Potato starch
• Potato flour
• Snack food