Table 2.

Application of plant proteases in meat tenderization.

Enzyme	Sample	Treatment	Positive Effect	Negative Effect	Reference
Papain	Spent hen leg cuts	-0.025% papain -Infusion and forking technique	-Improve tenderness, salt soluble protein, WHC, emulsifying tendency, and emulsion stability	N/A	[124]
Papain	Yak meat	-Injection of 80 U/mL papain	-Reduce shear force -Improve tenderness -Increase WHC	-Degrade color	[110]
		-Injection of 80 U/mL papain -Incubation for 30 min at 55 °C -Followed by HPP at 50 MPa for 15 min	-No color changes -Improve tenderness -Increase WHC	N/A
Papain	Jumbo squid (Dosidicus gigas)	-Incubation with papain solution for 40 min in a 30 °C water bath	-Improve tenderness -Reduce the muscle hardness -Reduce shear force -Reduce myofibrillar protein content	-Reduce WHC	[119]
Bromelain	Brahman cattle round cuts	-Treatment with freeze-dried bromelain powder extracted from pineapple crown	-Decrease hardness	-Reduce WHC -Reduce moisture content -Degrade color -Increase cooking loss	[65]
Bromelain	Buffalo meat	-Soaking with pineapple fruit extract	-Improve tenderness -Increase (WHC) -Reduce the cooking loss or shrinkage	N/A	[62]
Bromelain	Beef round cuts	-Treatment with bromelain powder from pineapple crown	-Increase amino acids content -Increase tenderness	-Reduce WHC	[70]
Ficin	Camel round cuts	-Treatment with 100 ppm papain, stored at a temperature 4 °C for 4 days	-Decrease hardness, springiness, cohesiveness, gumminess, chewiness, and shear force -Increase tenderness	N/A	[79]
Ficin	Mutton	-Treatment with 0.10 g/L ficin	-Reduce the hardness of tan mutton by 8% -Preserving the color of meat	-Reduce WHC	[77]
		-Incubation of the treated sample with 0.10 g/L ficin at 55 °C for 1 h and followed by HPP at 50 MPa or 150 MPa for 15 min	-Reduce the meat hardness by 48% if 50 MPa of pressure used and 41% if 150 MPa of pressure used -Reduce the cooking loss and centrifugal loss -High sensory score for tenderness, flavor, and texture	N/A
Actinidin	Pork muscle and	-Treatment with actinidin at 0.5 mg/100 g of muscles	-Increase tenderness -Reduce shear force	N/A	[2]
	rabbit muscle
Actinidin	Brisket steaks	-Injection of 5% of a 3 mg/mL solution of commercial actinidin extract (Actazin™ from Anagenix Ltd.) -Followed by vacuum tumbling and sous vide cooking process for 30 min at 70 °C	-High acceptability -High sensory score for tenderness, juiciness, and flavor -No changes in pH, color, and cooking loss	N/A	[83]
Zingibain	Chicken breast	-Treatment with crude ginger extract	-Reduce shear force -Increase myofibrillar fragment index -Reduce myofibrillar fragment length -Increase tenderness -Not affecting cooking loss	N/A	[94]
Cucumin	Buffalo meat	Cucumis extract (5% w/v) and ginger extract (0.2% w/w)	-Increased collagen and myofibrillar protein solubility -Lowered shear force -Improved sensory attributes	-Extensive proteolysis	[43]
Cucumin	Goat meat curry	Cucumis powder (2.0%) spray, citric acid (1.0%)	-Increased soluble collagen, lowered shear force	-	[125]