Food Standard and Quality Control

Lesson 06 : Factors affecting food quality


Air that is too dry or too damp damages many fresh foods. Excess humidity can lead to the growth of moulds and bacteria on meat, and fungus on fruit, vegetables and dry cereals. Excessive dryness can dehydrate meats as well as some fruits and vegetables. Controlling humidity is often a question of how air is circulated around products in trucks, shipping containers and storage areas. In turn, air flow is dependent on the type of containers in which food is packed (net bags for certain kinds of vegetables, slatted cartons for certain fruits), and the way these containers are packed together, e.g., with relatively little air flow among them or with spacers between cartons specifically designed to enhance air flow.

Example: Potatoesed for processing pose considerable challenges in that storage at temperatures sufficiently low to maintain dormancy causes the formation of higher sugars in the tubers. These lead to browning of the potato and to an increase in the levels of acryl amides formed during processing, from the interaction of the sugars with amino acids naturally present.

To avoid the higher sugar levels potatoes for processing are therefore typically stored at 7-9°C. Discoloration from high sugar levels is even more important in potatoes for chip production so these are stored at 9-12°C to help keep sugar levels down.

At these temperatures, sprouting will also cause irregular sugar concentrations in the tubers, resulting in irregular fry colours. Use of effective sprout suppression is therefore vital during storage.

Last modified: Thursday, 16 February 2012, 7:15 AM