TY - JOUR

T1 - Hydrolysis of chlorogenic acid in apple juice using a p-coumaryl esterase of Rhizoctonia solani

AU - Siebert, Mareike

AU - Berger, Ralf Günter

AU - Pfeiffer, Franziska

N1 - Funding information: We thank the panellists for their participation in sensory tests. M.S. is grateful to Gottfried Wilhelm Leibniz University of Hannover for granting a scholarship for researching enzymatic ways to food quality improvement.

PY - 2019/10/18

Y1 - 2019/10/18

N2 - BACKGROUND: Apple juice is rich in polyphenolic compounds, especially in chlorogenic acid. A sour and bitter taste has been attributed to the compound. Chlorogenic acid in coffee powder was quickly hydrolysed by a p-coumaryl esterase of Rhizoctonia solani (RspCAE) at its optimal pH of 6.0. It was unknown, however, if RspCAE would also degrade chlorogenic acid under the strongly acidic conditions (pH 3.3) present in apple juice. RESULTS: Treatment of apple juice with RspCAE led to a chlorogenic acid degradation from 53.38 ± 0.94 mg L−1 to 21.02 ± 1.47 mg L−1. Simultaneously, the caffeic acid content increased from 6.72 ± 0.69 mg L−1 to 19.33 ± 1.86 mg/L−1. The aroma profile of the enzymatically treated sample and a control sample differed in only one volatile. Vitispirane had a higher flavour dilution factor in the treated juice. Sensory analysis showed no significant difference in the taste profile (p < 0.05). CONCLUSION: These results demonstrated a high stability and substrate specificity of RspCAE. An increase in caffeic acid and a concurrent decrease in chlorogenic acid concentration may exert a beneficial effect on human health.

AB - BACKGROUND: Apple juice is rich in polyphenolic compounds, especially in chlorogenic acid. A sour and bitter taste has been attributed to the compound. Chlorogenic acid in coffee powder was quickly hydrolysed by a p-coumaryl esterase of Rhizoctonia solani (RspCAE) at its optimal pH of 6.0. It was unknown, however, if RspCAE would also degrade chlorogenic acid under the strongly acidic conditions (pH 3.3) present in apple juice. RESULTS: Treatment of apple juice with RspCAE led to a chlorogenic acid degradation from 53.38 ± 0.94 mg L−1 to 21.02 ± 1.47 mg L−1. Simultaneously, the caffeic acid content increased from 6.72 ± 0.69 mg L−1 to 19.33 ± 1.86 mg/L−1. The aroma profile of the enzymatically treated sample and a control sample differed in only one volatile. Vitispirane had a higher flavour dilution factor in the treated juice. Sensory analysis showed no significant difference in the taste profile (p < 0.05). CONCLUSION: These results demonstrated a high stability and substrate specificity of RspCAE. An increase in caffeic acid and a concurrent decrease in chlorogenic acid concentration may exert a beneficial effect on human health.

KW - apple juice

KW - chlorogenic acid

KW - p-coumaryl esterase

KW - Rhizoctonia solani

UR - http://www.scopus.com/inward/record.url?scp=85071341463&partnerID=8YFLogxK

U2 - 10.1002/jsfa.9940

DO - 10.1002/jsfa.9940

M3 - Article

C2 - 31325326

AN - SCOPUS:85071341463

VL - 99

SP - 6644

EP - 6648

JO - Journal of the Science of Food and Agriculture

JF - Journal of the Science of Food and Agriculture

SN - 0022-5142

IS - 14

ER -