Shelf-life boost? Potato peel extract can delay bread staling, say Italian researchers

Potato peel extracts may not only add fiber but can also be added to bread to extend shelf-life, according to research by the University of Parma.

Potato peel has previously been touted as an added source of fiber through extracts usually added in large quantities - 5–20%. But researchers have found other benefits.

Small amounts delay staling

A study published in the journal Food Chemistry by Elena Curti and her team at the University of Parma says the extracts could delay bread staling.

“Potato fiber improved the texture of bread, possibly by a retention of water allowing for the maintenance of a softer crumb texture during storage,” said the study.

“Potato fiber (extracted from potato peel) was found to have an important effect, when added in limited amounts (0.4%), on bread properties during storage,” it continued.

Study design

In the study, Curti and her team assessed two potato fiber fortified breads against a control bread. Both fortified breads had 0.4% of potato fiber by weight, but one had had greater water content.

They used a potato fiber named Hi-Fiber 115 from Italian functional ingredients firm Hi-Food. All breads were made with wheat flour in a home bread maker.

The scientists compared physio-chemical properties such as water activity, moisture content and frozen water content over seven days of storage.

They also examined Nuclear Magnetic Resonance to compare molecular activity.

Soft texture

Curti et al. found the texture of the potato fiber breads was softer than the control. The fortified breads displayed decreased rigidity and other factors that helped maintain the product during storage.

“More information should be collected to better understand the nature of potato fibre interactions with other bread components (e.g. starch),” said the study.

“The effect of higher amounts of potato fiber on bread staling could also be considered, to evaluate the optimal level of addition that represents the compromise between technological and sensory quality. The implementation of potato fiber addition at industrial level could be in last instance carried out,” it concluded.

Source:

Food Chemistry, Vol. 195, 15 March 2016, 64–70

doi:10.1016/j.foodchem.2015.03.092

‘The use of potato fibre to improve bread physio-chemical properties during storage’

Authors: Elena Curti, Eleonora Carini, Agoura Diantom, Elena Vittadini