Enzymatic browning reaction of apple juices prepared using a blender and a low-speed masticating household juicer

Figures & data

Table 1. General properties of apple juice prepared using a blender (BLD) or a low-speed masticating (LSM) household juicer.

	BLD	LSM
Yield (%)	88.8 ± 2.2^b1	76.2 ± 4.5^a
Total soluble solids (°Brix)	12.1 ± 0.2^b	11.4 ± 0.2^a
pH	4.42 ± 0.10^ns2	4.49 ± 0.19^ns
Titratable acidity (%)	0.15 ± 0.01^ns	0.14 ± 0.01^ns

¹ The data with different letters are significantly different (p < 0.05).

² Not significant.

Table 2. Color values of apple juice prepared using a blender (BLD) or a low-speed masticating (LSM) household juicer.

	Non-Blanched		Blanched^1
	BLD	LSM	BLD	LSM
L	67.6 ± 0.4^a2	73.5 ± 0.8^b	76.0 ± 0.2^c	84.3 ± 0.9^d
a	12.0 ± 0.1^d	1.9 ± 0.1^c	–3.6 ± 0.2^b	–5.8 ± 0.1^a
b	70.3 ± 0.3^d	53.2 ± 0.4^c	34.4 ± 0.2^b	24.3 ± 0.2^a

¹ The apples were incubated for 10 min at 80°C before juice extraction.

² The data with different letters are significantly different (p < 0.05).

Figure 1. Color change of apple juice immediately following preparation using a blender (BLD) or a low-speed masticating (LSM) household juicer. A, non-blanched BLD juice; B, non-blanched LSM juice; C, blanched BLD juicer; and D, blanched LSM juice.

Figure 2. Polyphenol oxidase (PPO) activity of apple juice prepared using a blender (BLD) or a low-speed masticating (LSM) household juicer (A) in the absence of Triton X-100 and (B) in the presence of 0.05% Triton X-100. Fresh apple juices were filtered through gauze (whole juice), and centrifuged at 500 g for 20 min for the separation of supernatant from precipitate. Data are expressed as mean ± SD (n = 3). The data with different letters are significantly different (p < 0.05).

Figure 3. Antioxidant contents of non-blanched and blanched apple juices prepared using a blender (BLD) or a low-speed masticating (LSM) household juicer. (A) Total polyphenol content; and (B) total flavonoid content. ¹⁾mg of tannic acid equivalent per mL of juice; and ²⁾mg of catechin equivalent per mL of juice. Data are expressed as mean ± SD (n = 3). The data with different letters are significantly different (p < 0.05).

Figure 4. Antioxidant activities of non-blanched and blanched apple juice prepared using a blender (BLD) or a low-speed masticating (LSM) household juicer. (A) ABTS radical cation decolorization activity; and (B) DPPH radical scavenging activity. ¹⁾mg of Trolox equivalent per mL of juice; and ²⁾μL of apple juice per mL of reaction mixture. Data are expressed as mean ± SD (n = 3). The data with different letters are significantly different (p < 0.05).