Freezing bread preserves freshness and alters starch structure

Freezing bread can serve both as a method for preservation and as a way to alter its nutritional impact. To maintain freshness, bread should be frozen while fresh at −18 °C, ideally in airtight bags to prevent drying. Sliced bread or rolls can be stored for approximately one to three months.

Beyond preservation, the process of freezing and thawing bread triggers a biochemical process known as retrogradation. This process rearranges starch chains to create resistant starch (Type 3), which is more difficult for digestive enzymes to break down into glucose. For individuals with diabetes, this can result in a slower rise in blood sugar levels and a reduced insulin requirement. Research from Oxford Brookes University suggests that toasting the bread after thawing can further enhance this effect.