Brazzein Tipped to Become the Next Big Sweetener

23 Aug 2016 --- Scientists from the ACS' Journal of Agricultural and Food Chemistry have reported a step toward the commercial production of a fruit protein called brazzein that is far sweeter than sugar - and has fewer calories.

Brazzein first attracted attention as a potential sugar substitute years ago. Making it in large amounts, however, has been challenging. Purifying it from the West African fruit that produces it naturally would be difficult on a commercial scale, and efforts to engineer microorganisms to make the protein have so far yielded a not-so-sweet version in low quantities. The lead author of the study, Kwang-Hoon Kong Ph.D, and colleagues are working on a new approach using yeast to churn out brazzein.

Speaking with FoodIngredientsFirst, Kong explains that brazzein is the answer to low sugar and high protein diets. “Brazzein contains 4 calories per gram but is so sweet that any food portion will contain virtually zero calories. And it is also a protein and not a carbohydrate, it does not affect blood sugar and is safe for diabetics,” says Kong.

“Brazzein is one hundred percentage protein,” claims Kong. “It is the smallest (M.W 6473) of the protein sweeteners discovered so far and it is composed of a single chain of 54 amino acid residues.”

Working with Kluyveromyces lactis, the researchers coaxed the yeast to overproduce two proteins that are essential for assembling brazzein. By doing so, the team made 2.6 times more brazzein than they had before with the same organism. A panel of tasters found that the protein produced by this approach was more than 2,000 times sweeter than sugar.

“Brazzein also has a lower carbon footprint than stevia or monk fruit,” says Kong. “It costs about $40 per gram in our laboratory scale and can be grown outside of West Africa. Actually in our laboratory, Brazzein has been expressed in the yeast Kluyveromyces lactis, which is “generally regarded as safe” (GRAS).”

“It has an excellent taste similar to sugar,” Kong continues, “In tests it was shown to be superior to other sweeteners, being closer to sugar with little or no metallic or bitter aftertaste. As with all potent sweeteners the onset and duration of the sweetness is somewhat different and longer than sugar. Also, Brazzein combines well with most high intensity sweeteners such as acesulfame-K and aspartame, providing both quantitative and qualitative synergy. It improves stability, flavor and mouth feel when blended with acesulfame-K and aspartame, either alone or blended. It typically reduces the side taste of other sweeteners, for example, a blend of stevioside and brazzein is superior in taste quality to stevioside alone.”

by Elizabeth Kenward