Low Field NMR Studies of Wheat Bread Enriched with Potato Juice During Staling

Abstract

Potato juice is a by-product in the production of starch from potato tubers. However, published studies indicate that it is a source of bioactive compounds with antioxidant and anti-inflammatory effects. The use of health-promoting additives may, however, affect the quality of the fresh final product as well as the stored one. Water behavior is one of the parameters whose analysis allows for the monitoring of the shelf life of products. Therefore, the research reported in this paper was aimed at investigating the effect of replacing wheat flour with spray-dried potato juice (SDPJ) at 2.5%, 5% and 7.5% on water behavior during bread staling. 1H Nuclear Magnetic Resonance (NMR) was used to analyze the impact of SDPJ on the dynamics of water in bread crumb. The NMR analyzes revealed that 7.5% addition of SDPJ resulted in an increased ratio of bound to bulk water (decreased T1 spin-lattice time) and decreased mobility of bulk water (decreased T22 spin-spin time). The enriched breads also showed different dynamics of water during storage, however, in each of the analyzed variants a slight increase in T1 was noted. It has also been shown that enrichment of bread in SDPJ accelerates the evacuation of water from the polymer network.

Keywords

• bread staling
• potato juice
• 1h nmr
• water activity
• water behavior
• water dynamics