Protein-rich red seaweed extract can be used in bread to aid heart health, say researchers.
The study published in the Journal of Food Science and Technology investigated use of protein hydrolysates from red seaweed – palmaria palmate – found in Europe and America.
The researchers from Ireland and the UK looked into this compound because of its renin inhibitory properties – the ability to treat high blood pressure and therefore prevent cardiovascular disease – which they discovered in an earlier 2012 study.
The aim of this study, they said, was to see if the renin inhibitory properties remained intact during baking and whether the end product held sensory appeal. The researchers tested the compound in wheat bread and buckwheat bread.
“This study confirmed that a renin inhibitory hydrolysate generated from P. palmate protein using the food grade enzyme papain retained bioactivity after the baking process,” they wrote.
“Furthermore, the textural and sensory attributes of the formulated breads containing the hydrolysate were deemed to be acceptable by a sensory panel.”
Bread widely consumed and heart problems rising
The researchers said use of the bioactive compound in a baked good, like bread, would be ideal because these products are so widely consumed.
“Baked goods are the most widely consumed foods in the world and therefore have great potential as vehicles for bioactive ingredients delivery. Indeed, many bread companies enrich their baked products with folic acid.”
Bakery manufacturers also use baked goods to add other health-promoting ingredients like protein and omega-3, they added.
As cardiovascular disease continues to impact people across the globe, bread would be an excellent medium to aid preventative measures, the researchers said.
“Approximately half of the global burden of cardiovascular disease can be attributed to hypertension or high blood pressure,” they said. And while this can be controlled through changes in dietary habits and through pharmacological treatments, they said protein hydrolysates from red seaweed used in bread looked promising.
“Although the area of healthy ingredients and functional foods is currently being widely researched, seaweeds still represent a relatively untapped source of plant protein,” the researchers said.
Lower loaf volume, but common with protein
The addition of 4% seaweed protein hydrolysate to wheat breads did result in a decreased loaf volume but the researchers said this was common when incorporating protein into bread. The protein compound led to a “greatly decreased breadloaf volume” in the buckwheat sample, they added.
The crust and crumb color of the breads also darkened with the incorporation of the red seaweed compound. However, the crumb structure remained strong – which is the most important for sensory aspects, the researchers said. “The addition of the renin inhibitory hydrolysate had no effect on the number of cells, cell wall thickness or cell volume of the breads.”
In terms of flavor, the sensory panel did report a bitterness, common with protein hydrolysates the researchers said, but they added that there are “numerous strategies that can be employed to de-bitter” the compound. Methods could include flavor agents, further enzymatic treatment or bitter inhibiting compounds, they said.
Source: Journal of Food Science and Technology
Published: May 2014, Volume 56, Pages 398-405. Online ahead of print, doi: 10.1016/j.lwt.2013.11.031
“Increasing the health benefits of bread: Assessment of the physical and sensory qualities of bread formulated using a renin inhibitory Palmaria palmate protein hydrolysate”
Authors: C. Fitzgerald, E. Gallagher, L. Doran, M. Auty, J. Prieto and M. Hayes