In addition to showing a high ability to encapsulate the casein ingredient, the soy protein isolate-pectin mixture was found to reduce the bitter taste of the hydrolysate, according to findings published in Food Research International.
“More than masking the taste of the casein hydrolysate, the microcapsules produced in this study may add nutritional value to the product in which they are incorporated due to inherent properties of the components,” wrote the authors, led by Debora Mendanha.
“The casein hydrolysate has functional properties, additionally pectin is a soluble fibre and soy protein has high nutritional value.”
Researchers from the University of Sao Paulo used Solae’s Supro soy protein isolate (SPI) and CP Kelco’s Genu low-methoxy pectin to encapsulate Kerry’s Hyprol casein hydrolysate. The casein ingredient is intended for use as a protein-source in infant products, and for enricing the protein content of food and beverages.
With the fear of commodification continuously looming, food manufacturers are turning to microencapsulation technologies as a way of achieving much-needed differentiation and enhancing product value. Many scientific studies have reported promising results for pectin to encapsulate a range of different ingredients.
Study details
The researchers fixed the SPI and pectin ratio at one to one, and encapsulated three different concentrations of the casein hydrolysate: 50, 100 and 150 per cent of the total mass of the polymers.
All three formulations formed microcapsules, said the researchers, and all “reduced the bitter taste, the hygroscopicity and allowed controlled release properties of the casein hydrolysate”, they added.
The capsule with the lowest casein content was considered most adequate, they said, because of its higher encapsulation efficiency (over 90 per cent) and lower ability to absorb water (hygroscopicity).
When tested by a panel of 20 trained tasters, all of the microencapsulated samples were rated as less bitter than the free casein hydrolysate, said the researchers.
Mendanha and her co-workers considered this an interesting approach for the bitter taste masking of a value-adding ingredient, considering that both SPI and pectin are “abundant, inexpensive and renewable raw materials”, they said.
Source: Food Research International
Volume 42, Issue 8, Pages 1099-1104
“Microencapsulation of casein hydrolysate by complex coacervation with SPI/pectin”
Authors: D.V. Mendanha, S.E. Molina Ortiz, C.S. Favaro-Trindade, A. Mauri, E.S. Monterrey-Quintero, M. Thomazini