Dried bonito stock, a stock used extensively in Japanese cuisine, was also found to enhance the saltiness of reduced-salt foods, according to findings published in the Journal of Food Science.
“These results suggest that saltiness enhancement by dried bonito stock was caused by the characteristic taste (excluding umami) of dried bonito stock, while its characteristic aroma and umami were involved in preventing the loss of palatability of a low-salt diet,” wrote the researchers, led by M. Manabe from Doshisha Women’s College of Liberal Arts in Kyoto.
“Moreover, it was found that using a combination of [bonito] and dried kelp, as material for making stock, could contribute effectively to the preparation of palatable salt-reduced foods in Japan,” they added.
A body of evidence has linked excess salt (sodium chloride) in the diet to an increased risk of high blood pressure and stroke. Campaigns are underway around the world to encourage consumers to reduce their daily intake. The UK's Food Standards Agency (FSA), for example, advises that adults should consume no more than six grams of salt a day.
While an important part of reformulating foods to contain less salt lies with enhancing the taste of the salt that is there, ingredients companies are collaborating with their customers to do their part in reducing sodium in the individual components that go in to a finished product.
The Japanese researchers tested two kinds of dried bonito, arabushi and karebushi, and found that the karebushi type was most effective for “improving the palatability of food, regardless of the intensity of its saltiness”.
Furthermore, “the karebushi-dried kelp stock, without the addition of monosodium glutamate (MSG), effectively enhanced saltiness and improved the overall palatability of salt-reduced food,” said the researchers.
The compound inosine 5'-monophosphate (IMP) is known to be a major contributor to the flavor that has ensured the popularity of dried bonito as a stock, and like MSG is another typical umami substance.
Potential for prepared foods
“Our results would be useful in the development of new ways of preparing palatable salt-reduced foods,” wrote the researchers.
“Furthermore, invention of new seasonings to improve the palatability of salt-reduced food could make use of these findings,” they concluded.
Source: Journal of Food Science
Published online ahead of print, doi: 10.1111/j.1750-3841.2009.01283.x
“Improving the Palatability of Salt-Reduced Food Using Dried Bonito Stock”
Authors: M. Manabe, S. Ishizaki, T. Yoshioka, N. Oginome
Abstract available here.