Led by Rizana Imtiaz, a research technologist at dairy giant Fonterra, the team revealed that, whey protein concentrates seem to be important in reducing firmness over time, whilst milk protein concentrates play various roles in texture depending on the modifications made during the manufacture of the ingredient.
Imtiaz and her research colleagues said the design approach used in the study“could be applied to a bar manufacturer's specific formulation to develop a predictive model that will help them adjust key ingredient levels to manipulate the texture in bars.”
“Protein bar manufacturers will be able to select the type of dairy protein and the level of the proteins in a blend required to achieve desired texture in bars based on the findings of this study,” said the researchers.
“This study has also shown the importance of the crumbliness/cohesiveness texture dimension and investigated a method to quantify this using instrumental texture analysis,” they added.
Protein performance
The research team noted that the type of protein or the combination of proteins used in high protein bars “can have a significant influence on the texture of the bars.”
“The most common protein source used in the industry is a combination of dairy protein and soy protein,” noted Imtiaz – adding that whilst a number of different dairy proteins are used in such bars, the most preferred dairy proteins tend to be calcium caseinate and whey protein hydrolyzate.
However, manufacturers desire different textures in their bars. “For this purpose, understanding the effect of proteins and protein blends on the two main texture dimensions in bars will be useful,” said the researchers.
“Using this knowledge, it will be possible to calculate or predict the texture in bars.”
Study details
The new study assessed the influence of three functionally modified dairy proteins – including one whey protein concentrate and two milk protein concentrates – on the texture of high protein bars.
“A mixture design was used to study the synergistic effects of these three proteins on bar texture,” explained Imtiaz and her colleagues.
Mathematical models were then developed to optimise the texture over a 12-month storage period for bars using one or more of the three proteins.
The team noted that each of the three dairy proteins gave unique texture in bar, whilst blending the proteins together “demonstrated synergistic and/or antagonistic effects on the firmness and crumbliness/cohesiveness of the bars.”
Whey protein concentrate proved to be important to minimize firmness over time, whilst the modified milk protein concentrates performed differently from each other in bars due to the different modifications made during the manufacture of these ingredients.
“This study was successful in developing mathematical models to calculate the texture of high protein bars that can be achieved with specific ratios of the three dairy proteins … Furthermore, the model can predict the texture changes over a 12-month storage period for bars with specific protein blends.”
