Development of Value-Added Butter by Incorporating Whey Protein Hydrolysate-Encapsulated Probiotics

Abstract

The probiotic foods market is growing exponentially; however, probiotics' survivability and interaction with product attributes pose major challenges. A previous study of our lab developed a spray-dried encapsulant utilizing whey protein hydrolysate-maltodextrin and probiotics with high viable counts and enhanced bioactive properties. Viscous products such as butter could be suitable carriers for such encapsulated probiotics. The objective of the current study was to standardize this encapsulant in salted and unsalted butter, followed by storage stability studies at 4 °C. Butter was prepared at a lab-scale level, and the encapsulant was added at 0.1% and 1%, followed by physiochemical and microbiological characterization. Analyses were conducted in triplicates, and means were differentiated (p < 0.05). The viability of probiotic bacteria and the physicochemical characteristics of the butter samples with 1% encapsulant were significantly higher as compared to 0.1%. Furthermore, the 1% encapsulated probiotics butter variant showed a relatively higher stability of probiotics ratio (LA5 and BB12) than the control with unencapsulated probiotics during storage conditions. Although the acid values increased along with a mixed trend of hardness, the difference was insignificant. This study thus provided a proof of concept for incorporating encapsulated probiotics in salted and unsalted butter samples.

Keywords: butter; probiotics; whey proteins.

Figure 1

Confocal Laser Scanning micro image of WPH-MD probiotic encapsulant in butter matrix. Nile Red Fluorescence (red) represents fat phase and Fluorescein Isothiocyanate (green) represents protein bodies.

Figure 2

Frequency sweep measurements (storage and loss modulus) using a parallel plate system of 1% WPH-MD probiotic, 0.1% WPH-MD probiotic and control unsalted butter samples. The solid lines represent the trend lines for storage modulus (G′) and non-solid represents the trend lines for loss modulus (G″). The grey colored trend line represents the 1% WPH-MD probiotic unsalted butter variant, green represents 0.1% WPH-MD probiotic butter variant, and blue represents control with no WPH-MD probiotic encapsulant addition.

Figure 3

Frequency sweep measurements (storage and loss modulus) using a parallel plate system of 1% WPH-MD probiotic, 0.1% WPH-MD probiotic and control salted butter samples. The solid lines represent the trend lines for storage modulus (G′) and non-solid represents the trend lines for loss modulus (G″). The pink colored trend line represents the 1% WPH-MD probiotic unsalted butter variant, yellow represents 0.1% WPH-MD probiotic butter variant, and black represents control with no WPH-MD probiotic encapsulant addition.

Figure 4

Textural Profile Analysis of 1% WPH-MD probiotic butter variants. (a) TPA of 1% WPH-MD probiotic unsalted butter; (b) TPA of unsalted control; (c) TPA of 1% WPH-MD probiotic salted butter; (d) TPA of salted control.

Figure 5

Viable probiotic counts of (LA5 on MRS and BB12 on MRS, L-cysteine) unsalted butter samples during storage ($4 °\mathrm{C}$).

Figure 6

Viable probiotic counts of (LA5 on MRS and BB12 on MRS, L-cysteine) salted butter samples during storage ($4 °\mathrm{C}$).

Figure 7

Acid value of salted WPH-MD probiotic butter variants during storage ($4 °\mathrm{C}$).

Figure 8

Acid value of unsalted WPH-MD probiotic butter samples during storage ($4 °\mathrm{C}$).

Figure 9

Hardness of salted WPH-MD probiotic butter samples during storage at refrigerated conditions ($4 °\mathrm{C}$).

Figure 10

Hardness of unsalted WPH-MD probiotic butter variants during storage at refrigerated conditions ($4 °\mathrm{C}$).