Functionality of oat based food ingredients

Sammanfattning: This master thesis work was performed in collaboration with the agricultural cooperative Lantmännen. With the ambition to take a world leading role in the development of unique products based on oats, Lantmännen has developed two oat based powders; one protein powder, PrOatein™, and one β-glucan powder, PromOat®. The aim of this master thesis project was to investigate the functional properties of the products and evaluate their potential use as ingredients in food formulations. Based on this, potential food product prototypes using PrOatein™ and PromOat® as ingredients were developed. The analysis of PrOatein™ was aimed to investigate the protein solubility and how it was affected by changes in pH and ionic strength, and the combination of the two. It was found that solubility showed no or little change in a pH range of 3.14-6.42. Ionic strengths in the range of 7.63-1030 mmol/L had effect on solubility at pH 3.15, 4.80 and 5.24 but not at pH 6.42 and 4.32. The overall solubility is rather low, ≈5% of the total protein. High pressure homogenisation as a pretreatment was shown to somewhat increase the solubility, decrease particle size, increase sedimentation time and increase the total volume of the sediment. The analysis of PromOat® was aimed to investigate the rheological properties and how it was affected by changes in pH and ionic strength, as well as at what concentration a yield stress was present. PromOat® showed Newtonian flow behavior at a concentration of 1% w/v and shear thinning behavior at concentrations of 3, 6 and 9% w/v. The flow behavior was unaffected in a pH range of 3.14-6.42 and at ionic strengths in the range of 6.83-1010 mmol/L. Yield stress was seen above a PromOat® concentration of 7.4% w/v. Overall, PromOat® serves well to be used as a viscosity modifier in food products. The part of the project devoted to product development aimed to develop prototypes of high protein (≥20 energy%) and high fiber (≥3 g fiber/100 kcal) products. High concentration of PrOatein™ gave a tendency of astringency to the mouthfeel of the formulation while PromOat® gave a sensation of filmyness. However, a combination of the two seemed to counteract the astringency and filmyness that the ingredients contributed with separately. It was concluded that the combination of PrOatein™ and PromOat® make good ingredients for the formulation of a smoothie and a pudding with suitable viscosity and a pleasant mouthfeel. The developed food products contained sufficient amounts of PromOat® and PrOatein™ to be claimed as high protein and high fiber products.