Research Article
Application of Milk-Clotting Protease from Aspergillus oryzae
DRDFS13 MN726447 and Bacillus subtilis SMDFS 2B
MN715837 for Danbo Cheese Production
Jermen Mamo ,
1,2
Paulos Getachew,
3
Mbugua Samuel Kuria,
4
and Fassil Assefa
1
1
Microbial, Cellular and Molecular Biology Department, Addis Ababa University, Addis Ababa, Ethiopia
2
Department of Biology, College of Natural and Computational Science, Debre Berhan University, Debre Berhan, Ethiopia
3
Centers for Food Science and Nutrition, Addis Ababa University, Addis Ababa, Ethiopia
4
Food Science, Nutrition and Technology Department, College of Agriculture and Veterinary Science, University of Nairobi,
Nairobi, Kenya
Correspondence should be addressed to Jermen Mamo; jermenmamo@yahoo.com
Received 13 April 2020; Revised 25 May 2020; Accepted 26 May 2020; Published 10 June 2020
Academic Editor: Seyed Mohammad Taghi Gharibzahedi
Copyright©2020JermenMamoetal.isisanopenaccessarticledistributedundertheCreativeCommonsAttributionLicense,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
is study aimed to investigate the efficiency, biochemical composition, and sensory quality of Danbo cheese produced using
proteases derived from the fungus and bacterium compared to the commercial product. A fungal enzyme from Aspergillusoryzae
DRDFS13MN726447 and a bacterial enzyme from Bacillus subtilis SMDFS 2B MN715837 were produced by solid-state and
submerged fermentation, respectively. e crude enzyme from A. oryzae DRDFS13 and B. subtilis SMDFS 2B was partially
purified by dialysis and used for Danbo cheese production using commercial rennet (CHY-MAX® Powder Extract NB, Christian
Hansen, 2235 IMCU/g) as a control. e Danbo cheese produced using dialyzed fungal enzyme (E1) (267 U/mL), dialyzed
bacterial enzyme (E2) (522 U/mL), and commercial rennet (C) were analyzed for body property, organoleptic characteristics, and
proximate and mineral composition when fresh and after 2 months of ripening. ere was no significant difference in the cheese
yield (C =9kg, E1=8.6kg,and E2 = 8.9 kg) among the three treatments. e body properties of Danbo cheese produced with the
fungal enzyme (E1) were firm and acceptable as the control (C), whereas the Danbo cheese produced by bacterial enzymes has
shown a watery body. e overall organoleptic characteristics of Danbo cheese produced by the fungal enzyme (5.3) were similar
to control cheese produced by commercial rennet (5.5). Both cheese types were significantly different in organoleptic properties
from Danbo cheese produced by the bacterial enzyme (4.9). ere was no significant difference (p > 0.05) in the proximate
composition between the ripened Danbo cheese produced by fungal enzyme and the control cheese except for crude protein
content. However, the ripened cheese products showed a significant difference in their mineral composition except for sodium. In
conclusion, this study demonstrated that the fungal enzyme from Aspergillus oryzae DRDFS 13 is more appropriate for Danbo
cheese production than the bacterial enzyme from Bacillus subtilis SMDFS 2B. However, it requires further application of the
enzymes for the production of other cheese varieties.
1. Introduction
Cheese is one of the most important components of dairy
industries and more than 1000 different varieties are pro-
duced throughout the world [1]. Generally, different vari-
eties of cheese are industrially produced by using calf rennet
[2]. Among which, Danbo cheese is semihard cheese
characterized by surface ripening with few round pea-sized
holes and distinctive flavor and is consumed after ripening
for 2-3 months, but a few variants are allowed to mature
for up to 12 months [3]. e flavor of Danbo cheese
originates from smear bacteria that develop on the surface
during the first weeks of maturation [4]. It is originated
and most commonly consumed cheese in Denmark and
comprises about 13.2% of total Danish cheese production
[4, 5].
Hindawi
Journal of Food Quality
Volume 2020, Article ID 8869010, 12 pages
https://doi.org/10.1155/2020/8869010