Denaturation and Physical Characteristics of Spray-Dried Whey Protein Isolate Powders Produced in the Presence and Absence of Lactose, Trehalose, and Polysorbate-80

Abstract

The denaturation (loss of protein through aggregation and/or change in secondary structure) and physical characteristics such as powder morphology, particle size and size distribution, amorphous/crystalline behavior, and solubility of whey protein isolate (WPI) were investigated in a spray-drying process. The protective efficacy of sugars (lactose and trehalose) and low-molecular-weight surfactant polysorbate-80 (Tween-80) on the secondary structure (b-turn, b-sheet and a-helix) and physical characteristics of spray-dried WPI was quantified. The WPI, WPIþsugar, and WPIþTween-80 formulations were spray dried maintaining the total solids at 10% (w/w). The inlet and outlet temperatures were maintained at 180 and 80 C, respectively. The results showed that the loss of protein through denaturation and aggregation was not significant (p > 0.05). However, a significant (p < 0.05) alteration of the secondary structural elements was observed. Due to spray drying of WPI without protectants, the b-sheet and b-turn were decreased by 4.4 and 14.5%, respectively, and the random coil increased by 20.7%. The a-helix of WPI remained unaltered during the spray-drying process. The presence of Tween-80 effectively protected the a-helix and b-sheet but the b-turn remained vulnerable and was decreased. No significant (p > 0.05) change in the solubility of WPI was observed due to spray drying. Spray drying of WPIþsugar produced essentially amorphous particles. The dried powder particles were spherical with wrinkled or folded surface.

Physicochemical and functional properties of protein isolate produced from Australian chia seeds

“…Furthermore, the moisture evaporation flux in the spray drying process is very high, which results in strong evaporative cooling. All of these factors indicate that the temperature of CPI particles during spray drying was not high enough to denature protein during the drying process, which agrees with Haque et al (2015b)'s work on whey protein isolate.…”

Predictions of drying kinetics of aqueous droplets containing WPI-lactose and WPI-trehalose by application of composite reaction engineering approach (REA)

“…These stages insert numerous stresses on protein like heat stress, shearing stress and interfacial stress. These stresses denature considerable amount of protein during spray drying process (Anandharamakrishnan et al, 2007;Haque et al, 2015a).…”

Effects of infrared freeze drying on volatile profile, FTIR molecular structure profile and nutritional properties of edible rose flower (Rosa rugosa flower)

“…A ‘sugar region’, which may be contributed to by the stretching vibrations of CC and CO in glycosidic bonds and pyranoid rings, was detected in the absorption region of 1200–950 cm −1. 40 Moreover, the bands near 990, 1040, 1080 and 1150 cm −1 confirmed the existence of β‐glucans represented as β‐glycosidic bonds 41 . The absorption peak at 1045 cm −1 of the CO stretching and bending vibrations of the C‐OH groups of carbohydrates such as fructose and glucose was shifted to 1043 cm −1 and may be a result of the changes of some carbohydrates 39 .…”

“…Figure 7 shows the specific spectral deconvolution of different dried R. rugosa flower in the region 1700–1600 cm −1 . The peaks located at 1610–1640 cm −1 , 1640–1644 cm −1 , 1645–1659 cm −1 and 1660–1700 cm −1 are ascribed to β‐sheet, random coil structure, α‐helix and β‐turns, respectively 41 . As shown in Fig.…”