5.4 Soy Coffee

PRODUCT/PROCESS DESCRIPTION

Soy coffee is a fine, brown powder made from roasted soybeans which is used as a coffee substitute by people who do not take coffeine for religious or health reasons.

Principles of Preservation and Methods of Processing

Preservation is achieved by heat inactivation of enzymes and micro-organisms and by removal of water to inhibit recontamination during storage. The process involves roasting soybeans and grinding to a powder.

PROCESS FLOW DIAGRAM

QUALITY CONTROL

Hygiene

The heat treatment used in the process and the low moisture content of the product mean that this product is relatively free of the microbial dangers associated with wet low acid foods. Normal hygienic food handling is sufficient.

Raw Material Control

Beans should be free of husk, soils and other debris and free of insect damage. They should be stored in a cool dry room on raised pallets and protected from insects, birds and rodents.

Process Control

The main control points are the roasting and grinding stages of the process. Overheating leads to a burnt flavour and aroma and a colour that is too dark. Underheating produces lack of flavour and aroma, a colour that is too light and possibly incomplete inactivation of enzymes and contaminating micro-organisms. The particle size of the powdered product is determined by the extent of grinding and the aperture size of the sieve.

Product Control

The colour and aroma of the product can be made more uniform by blending different batches of powder.

PACKAGING AND STORAGE

The powder is hygroscopic and should therefore be packaged into moisture proof containers (e.g. strong polythene bags) and fully sealed. Care is necessary to prevent the powder from contaminating the heat seal of a plastic bag and making it ineffective. The package should be filled carefully to the declared weight.

Equipment:

· Oven
· Grinding mill
· Sieve
· Scales