Amelioration of cocoa organoleptics using A.oryzae cysteine proteases.

Pushpa, S. Murthy and Sneha, H. P. and Janardhan, P. and Kusumotoc, Ken-Ichi (2020) Amelioration of cocoa organoleptics using A.oryzae cysteine proteases. LWT - Food Science and Technology, 120. pp. 1-9. ISSN 0023-6438

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Abstract

The A.oryzae strains isolated from coffee were screened to evaluate their potential for production of acid aspartic protease. The strains with highest activity were then subjected to UV-mutagenesis and the lethality was determined by spore spread plate method. The mutant strain CPO 025 produced 1.3 × 104 U/ml, which is 1.53 fold higher than the parent with survival rate of 76 ± 2%. The Central Composite Rotatable Design(CCRD) based Response Surface Methodology(RSM) was employed to optimize the parameters for Aspartic protease production. The mutant strain subjected to solid-state fermentation (SSF) using wheat bran as substrate yielded 1820 U/mg specific activity with functional conditions of moisture (35%), inoculum (6.5 CFU/ml), fermentation duration (108 h), and temperature (28 °C). The partially purified proteases by DEAE-Sepharose had attributes with 6082 U/mg specific activity, optimum pH 3.6, temperature 35 °C and MW of 35 kDa. Enhanced activity by β-mercaptoethanol and inhibition by iodoacetic acid confirmed cysteine protease. Application of cysteine protease with cocoa beans upsurged flavour profile compared to the untreated beans. The elevated level of dimethylpyzarine and ketone3,5-Bis(tert-butyl)-4-hydroxy-propiophenone indicated efficient protein hydrolysis with desirable cocoa flavour. Thus cocoa organoleptic enhancement with flavourzyme can camouflage poorly fermented cocoa and economy of the industry.

Item Type:	Article
Uncontrolled Keywords:	A. oryzae Aspartic protease Cocoa Cysteine Flavourzyme
Subjects:	600 Technology > 07 Beverage Technology > 03 Cocoa 600 Technology > 08 Food technology > 16 Nutritive value > 05 Enzymes
Divisions:	Plantation Products Spices and Flavour Technology
Depositing User:	Food Sci. & Technol. Information Services
Date Deposited:	27 Apr 2020 06:21
Last Modified:	27 Apr 2020 06:21
URI:	http://ir.cftri.res.in/id/eprint/14263

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