Emulsion characteristics of salad dressings as affected by caprine whey protein concentrates

Figures & data

Figure 1. Elastic modulus (Gʹ) and viscous modulus (Gʺ) as a function of frequency of salad dressings made with 1.0% (w/w) protein incorporation.

CWP (♦); UWP (■); Aggregates (○); Bovine WPC (▲).

Figure 2. Microstructure of salad dressings added of whey protein products. 1: bovine whey protein concentrate; 2: aggregates powder; 3: unclarified caprine whey powder; 4: clarified caprine whey powder. Images a: product at 0.5% protein; images b: product at 1% protein. Images a and b: magnification of 1000x; image 4c: magnification of 4000x.

Table 1. Rheological properties [G*, Gʹ, and Gʺ] of salad dressings made with caprine cheese whey powders and bovine whey protein concentrate.

	CWP	UWP	Aggregates	Bovine WPC
0.5% Protein
G* (Pa)	1074.71±72.82 ^a	361.26±7.67 ^b	338.56±25.37 ^b	192.80±1.37 ^c
Gʹ (Pa)	1051.01±73.81 ^a	345.20±0.38 ^b	329.18±25.53 ^b	179.74±1.24 ^c
Gʺ (Pa)	223.73±3.61 ^a	88.83±2.09 ^b	78.78±1.99 ^c	69.74±0.36 ^d
1.0% Protein
G* (Pa)	1505.13±12.90 ^a	536.49±49.91 ^b	1552.50±73.54 ^a	212.47±22.04 ^c
Gʹ (Pa)	1478.63±12.20 ^a	523.80±49.36 ^b	1534.04±73.83 ^a	197.12±23.81 ^c
Gʺ (Pa)	280.82±4.89 ^a	115.71±7.90 ^b	237.16±4.19 ^c	78.52±0.18 ^d

CWP, clarified whey powders; UWP, unclarified whey powders; Aggregates, aggregates powders; Bovine WPC, Bovine whey protein concentrate. Mean values ± standard deviation.

a,b,c,d: Means within a row followed by different letters differ significantly (p < 0.05).

Table 2. Storage stability (%) of salad dressings made with caprine cheese whey powders and bovine whey protein concentrate after different periods and temperature of storage.

	CWP	UWP	Aggregates	Bovine WPC
0.5% Protein
Day 0	83.26±0.98	82.60±0.89	81.81±0.78	81.45±0.30
Day 1
25°C	83.04±0.98	83.93±0.55	83.79±0.14	81.86±0.96
4°C	84.23±0.86 ^ab	84.62±0.47 ^a	82.76±0.32 ^bc	82.31±0.48
6 months
25°C	94.81±1.56 ^a	92.35±0.32 ^ab	94.78±1.68 ^a	90.52±0.13 ^b
4°C	96.78±0.61 ^a	93.63±0.16 ^b	92.15±0.92 ^bc	91.56±0.83 ^c
1.0% Protein
Day 0	84.52±0.35 ^a	85.72±1.48 ^a	91.04±0.47 ^b	81.99±0.29 ^c
Day 1
25°C	88.12±1.99 ^a	87.86±0.08 ^a	93.35±0.77 ^b	83.59±0.43 ^c
4°C	88.00±0.01 ^a	87.85±0.06 ^a	92.86±0.11 ^b	83.96±1.44 ^c
6 months
25°C	100.00±0.00 ^a	96.94±1.13 ^b	100.00±0.00 ^a	88.85±1.58 ^c
4°C	100.00±0.00 ^a	97.13±0.01 ^b	100.00±0.00 ^a	93.81±1.19 ^c

CWP, clarified whey powders; UWP, unclarified whey powders; Aggregates, aggregates powders; Bovine WPC, Bovine whey protein concentrate. Mean values ± standard deviation.

a,b,c: Means within a row followed by different letters differ significantly (p < 0.05).

Table 3. Colour parameters (CIE L*a*b*) of salad dressings made with caprine cheese whey powders and bovine whey protein concentrate.

	CWP	UWP	Aggregates	Bovine WPC
0.5% Protein
L*	55.92 ± 2.25 ^a	55.72±0.51 ^a	55.73±0.19 ^a	49.63±0.78 ^b
a*	−0.74 ± 0.10 ^a	−0.64±0.00 ^ac	−1.27±0.05 ^b	−0.57±0.00 ^c
b*	5.27 ± 0.28 ^a	5.08±0.03 ^a	7.00±0.13 ^b	5.01±0.02 ^a
1.0% Protein
L*	66.93±4.77 ^a	62.63±0.39 ^ab	66.58±4.34 ^a	58.44±0.78 ^b
a*	−0.92±0.07 ^a	−0.89±0.00 ^a	−1.87±0.08 ^b	−0.69±0.02 ^c
b*	5.64±0.12 ^a	5.40±0.02 ^a	9.54±0.32 ^b	6.18±0.00 ^c

CWP, clarified whey powders; UWP, unclarified whey powders; Aggregates, aggregates powders; Bovine WPC, Bovine whey protein concentrate. Mean values (±) standard deviation.

a,b,c: Means within a row followed by different letters differ significantly (p < 0.05).