Quality Characteristics and Glass Transition Temperature of Hydrocolloid Pre-Treated Frozen Pre-Cut Carrot

Figures & data

Table 1 Effect of different hydrocolloid pre-treatments on instrumental texture parameters of frozen-thawed pre-cut carrot (n = 4)

		Hardness (N)		Fracturability (N)		Adhesiveness (Nm)
Treatment	Levels	Longitudinal	Transverse	Longitudinal	Transverse	Longitudinal	Transverse
Pectin	0.2	1.26±0.03^b	1.41±0.02^c	0.094±0.014^a	0.102±0.003^a	0.872±0.005^b	0.810±0.006^b
	0.3	1.43±0.04^c	1.59±0.08^d	0.108±0.009^a	0.113±0.002^a	0.789±0.011^c	0.740±0.006^c
	0.4	1.80±0.03^e	1.96±0.04^e	0.114±0.013^b	0.121±0.011^b	0.700±0.014^d	0.688±0.009^d
CMC	0.2	1.42±0.08^c	1.53±0.11^cd	0.085±0.016^a	0.095±0.016^a	0.911±0.008^a	0.887±0.007^b
	0.3	1.60±0.05^d	1.73±0.04^d	0.095±0.007^a	0.105±0.008^a	0.827±0.005^b	0.788±0.005^c
	0.4	2.07±0.13^e	2.22±0.14^f	0.107±0.018^a	0.117±0.006^b	0.749±0.003^c	0.639±0.008^d
Xanthan Gum	0.2	1.59±0.03^d	1.73±0.13^d	0.074±0.005^a	0.090±0.013^a	0.800±0.011^bc	0.767±0.012^c
	0.3	1.88±0.11^e	2.03±0.07^d	0.123±0.008^b	0.131±0.014^b	0.691±0.008^d	0.668±0.012^d
	0.4	2.61±0.06^g	2.74±0.08^g	0.133±0.010^b	0.141±0.003^b	0.588±0.013^e	0.570±0.007^e
Sodium Alginate	0.2	1.33±0.04^bc	1.49±0.13^c	0.089±0.014^a	0.103±0.008^a	0.936±0.012^a	0.879±0.011^b
	0.3	1.55±0.12^cd	1.78±0.02^d	0.086±0.009^a	0.117±0.008^b	0.828±0.004^b	0.823±0.015^b
	0.4	1.85±0.07^e	2.25±0.15^f	0.117±0.018^b	0.127±0.005^b	0.755±0.006^d	0.726±0.011^c
Control		0.84±0.04^a	1.10±0.17^a	0.075±0.015^a	0.088±0.003^a	0.975±0.005^a	0.962±0.009^a
Values with different superscripts in the same column differ significantly. Least significant difference (P < 0.05).

Figure 1 Effect of different hydrocolloid pre-treatments on drip losses of frozen-thawed pre-cut carrot. (P < 0.05).

Table 2 Instrumental color values and overall acceptability of the hydrocolloid pre-treated frozen-thawed pre-cut carrot (n = 4, n^x = 10)

	Levels	L*	a*	b*	OAA^x
Pectin	0.2	48.73±0.06^d	29.38±0.03^d	32.28±0.05^a	6.63±0.07^b
	0.3	49.31±0.04^b	28.71±0.02^c	35.41±0.02^b	6.86±0.08^c
	0.4	50.42±0.03^e	23.36±0.03^b	38.35±0.01^d	7.41±0.06^d
CMC	0.2	44.39±0.02^b	29.36±0.01^d	33.53±0.01^a	6.19±0.03^a
	0.3	46.17±0.03^c	25.46±0.03^b	35.81±0.03^b	6.38±0.08^b
	0.4	48.67±0.01^d	24.17±0.02^b	38.28±0.01^d	7.10±0.06^d
Xanthan	0.2	42.25±0.02^a	28.19±0.01^c	33.11±0.02^a	7.22±0.05^d
	0.3	44.86±0.03^b	25.59±0.02^b	35.65±0.02^b	7.85±0.03^f
	0.4	49.55±0.05^e	23.99±0.02^b	37.06±0.01^c	6.26±0.04^a
Sodium Alginate	0.2	42.12±0.03^a	28.44±0.03^i	33.48±0.04^a	7.57±0.03^e
	0.3	44.90±0.01^b	27.34±0.01^c	36.25±0.02^b	7.52±0.02^e
	0.4	47.39±0.04^c	24.81±0.02^b	38.81±0.03^d	6.86±0.03^c
Control		42.98±0.02^a	17.23±0.02^a	30.74±0.01^a	5.86±0.03^a
Values with different superscripts in the same column differ significantly. Least significant difference (P < 0.05).

Figure 2 DSC thermograms showing glass transition temperatures (T_g ″′) of the carrot samples pre-treated with (a) CMC, (b) Pectin, (c) Sodium Alginate, and (d) Xanthan gum. (Figure provided in color online.)

Table 3 Glass transition temperatures (T_g ″′), Onset temperature (T_o ) and Peak temperatures (T_p ) of the hydrocolloid pre-treated frozen-thawed pre-cut carrot (n = 3)

	Levels	Tg ″′ (°C)	To (°C)	Tp (°C)
Pectin	0.2	−1.41±0.03^c	−3.69±0.14^d	8.87±0.10^b
	0.3	−1.05±0.02^d	−3.20±0.05^c	10.64±0.04^c
	0.4	−0.63±0.06^e	−3.05±0.12^c	12.06±0.07^d
CMC	0.2	−1.50±0.05^c	−4.12±0.04^e	10.39±0.03^c
	0.3	−0.98±0.06^d	−4.22±0.06^e	11.24±0.02^d
	0.4	−0.28±0.13^f	−4.51±0.09^f	12.61±0.05^e
Xanthan	0.2	−2.60±0.09^b	−2.82±0.08^b	8.54±0.02^a
	0.3	−2.17±0.12^b	−2.74±0.03^ab	9.12±0.04^b
	0.4	−1.39±0.04^c	−2.68±0.02^a	10.24±0.04^c
Sodium Alginate	0.2	−2.73±0.07^b	−3.29±0.10^c	9.04±0.05^b
	0.3	−1.74±0.12^c	−3.12±0.03^c	10.23±0.03^c
	0.4	−1.28±0.08^c	−2.92±0.04^b	11.24±0.02^d
Control		−5.40±0.23^a	−2.41±0.05^a	8.36±0.08^a
Values with different superscripts in the same column differ significantly. Least significant difference (P < 0.05).