Enhancement on enzymolysis of pigskin with ultrasonic assistance

ABSTRACT

The fur is hard to decompose during the fermentation process of diseased swine carcasses. In order to enhance the enzymolysis of pigskin, the ultrasonic was proposed to use during the process of the enzymatic hydrolysis. The response surface optimization experiments were carried out with the DH (degree of hydrolysis) as the response value and the optimum conditions for enzymatic hydrolysis were determined. Based the optimum conditions, orthogonal experiments were carried out with ultrasonic frequency, power and time as variables, and optimal ultrasonic parameters were obtained. Without the assistance of ultrasonic, the descending order of influence factors on DH was, temperature＞SC(Substrate concentration)＞RES(The ratio of enzyme to substrate)＞pH. Moreover, the DH value is of 10.42% under the following optimal conditions: RES is of 16,006 U/g, the temperature is of 48.92°C, the SC is of 59.76 g/L and pH is of 10.43. Frequency has the greatest effect on DH, followed by power, and finally time. The optimum hydrolysis time is of 5 h, and the DH is of 22.94% were obtained under the following optimum ultrasonic pretreatment conditions: frequency combination is of (20,40,40), power is of 600 W and time is of 25 min. Comparing with the group without ultrasonic pretreatment, the DH for the ultrasonic assistance increased by 4%, the hydrolysis time was shorten by 3 h, and the total amino acids increased by 15.98%.

Graphical Abstract

KEYWORDS:

• Pigskin
• ultrasonic
• pretreatment
• enzymatic hydrolysis
• degree of hydrolysis

Highlights

1. Ultrasonic pretreatment was proposed for enzymolysis of pigskin.

2. Degree of hydrolysis with the ultrasonic assistance increased by 4%.

3. The hydrolysis time with the ultrasonic assistance was shorten by 3 h.

4. Amino acids in hydrolysates increased by 15.98% with the ultrasonic assistance.

Acknowledgments

This work was supported by the [National Natural Science Foundation of China] under Grant [number 51706063]; [Young Key Teachers Training Program of Henan Higher Education Institutions] under Grant [number 2018GGJS028], and [Henan Youth Talent Project] under Grant [2019HYTP026].

Disclosure Statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [51706063]; Young Key Teachers Training Program of Henan Higher Education Institutions [2018GGJS028];Henan Youth Talent Project [2019HYTP026].