This article has been corrected. See "Erratum to: Comparisons of Beef Fatty Acid and Amino Acid Characteristics between Jeju Black Cattle, Hanwoo, and Wagyu Breeds" (Vol: 40, Issue:3, Page: 495)
ARTICLE

Comparisons of Beef Fatty Acid and Amino Acid Characteristics between Jeju Black Cattle, Hanwoo, and Wagyu Breeds

Seung-Hoon Lee1,https://orcid.org/0000-0001-6703-7914, Chung-Nam Kim2,https://orcid.org/0000-0003-0833-0111, Kyoung-Bo Ko2https://orcid.org/0000-0002-5837-0974, Se-Pill Park2https://orcid.org/0000-0002-6965-7831, Ho-Kyoung Kim3https://orcid.org/0000-0002-7995-1129, Jun-Mo Kim4,*https://orcid.org/0000-0002-6934-398X, Youn-Chul Ryu2,*https://orcid.org/0000-0001-8940-624X
Author Information & Copyright
1Division of Biotechnology, College of Life Science, Korea University, Seoul 02841, Korea
2Division of Biotechnology, SARI, Jeju National University, Jeju 63243, Korea
3Division of Food Nutrition and Culinary Art, Dong-Eui Institute of Technology, Busan 47230, Korea
4Department of Animal Science and Technology, College of Biotechnology and Natural Resources, Chung-Ang University, Anseong 17546, Korea

These authors contributed equally to this work.

*Corresponding author : Jun-Mo Kim, Department of Animal Science and Technology, College of Biotechnology and Natural Resources, Chung-Ang University, Anseong 17546, Korea Tel: +82-31-670-3263 Fax: +82-31-675-3108 E-mail: junmokim@cau.ac.kr
*Corresponding author : Youn-Chul Ryu, Division of Biotechnology, Jeju National University, Jeju 63243, Korea Tel: +82-64-754-3332, Fax: +82-64-725-2403 E-mail: ycryu@jejunu.ac.kr

© Korean Society for Food Science of Animal Resources. This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Received: Mar 28, 2019 ; Revised: Apr 09, 2019 ; Accepted: Apr 09, 2019

Published Online: Jun 30, 2019

Abstract

Jeju black cattle are known as one of Korea’s traditional cattle. However, Hanwoo is more well-known to Korean meat consumers as representative beef cattle. Despite the popularity of these two breeds, comparison of the nutritional characteristics between Jeju black cattle and Hanwoo have not been studied. Here, we compared the fatty acid and amino acid characteristics between two Korean traditional cattle and Wagyu breeds. A total of 62 cattle were used in this study. The Jeju black cattle beef had significantly higher unsaturated fatty acids than Hanwoo (p<0.05). Savory fatty acids, including oleic acid were also higher than in Hanwoo cattle (p<0.05). The negative flavor fatty acids, such as palmitic acid were significantly lower than in Hanwoo (p<0.001). On the other hand, linoleic acid which imparts a negative flavor was higher than Hanwoo (p<0.05). Amino acids, including alanine and glutamine, usually representative of the umami taste were present in significantly higher proportions in Jeju black cattle (p<0.05). In addition, bitter tasting amino acids, including valine, leucine, isoleucine, and methionine were lower in Jeju black cattle beef than in Hanwoo (p<0.05, p<0.001, p<0.001, and p<0.001 each). Taken together, our results suggest that Jeju black cattle beef had higher savory flavor and umami taste which affected consumers preference for the meat.

Keywords: beef; nutritional characteristics; Jeju black cattle; Hanwoo; Wagyu

Introduction

Based on Korean historical records, Korean native cattle have lived on the Korean peninsula since the fourth century (Kim and Lee, 2000). The Korean native cattle have traditionally included four cattle breeds, composed of three coat color patterns (Jo et al., 2012; Lee et al., 2014). The three color patterns are a brown or red, a black-striped brown, and two black color breeds (Lee et al., 2014). The Korean native cattle breeds were used as working cattle until the 1960s. With the development of farming technology, Korean native cattle became used as beef meat (Kim and Lee, 2000; Lee et al., 2014). The well-known Hanwoo cattle breed has the largest population in South Korea. The other three non-brown or red color breeds have smaller populations. Among the minor breeds, Jeju black cattle live only on Jeju Island (Han et al., 2011).

Jeju black cattle beef were a rare gift given to the king in the Chosun era. The king only could eat that beef on his birthday, New Year’s Day, and on Memorial Day of the royal family. Presently, Jeju black cattle beef is available at specialty butcher shops due to development of production technology. However, people recognize Hanwoo as the representative beef meat cattle of Korea and favor it for roasting. Wagyu is the popular Japanese cattle breed for its texture, flavor, and tenderness. The roasted beef is a popular meat food in South Korea. Consumers prefer the palatability and flavor from its marbled fat (Frank et al., 2016). Because of these preferences, beef consumption has increased every year (Korea Meat Industries Association, 2000). The flavor of beef meat is derived from its fatty acid content (Frank et al., 2016; Lorido et al., 2015). Fatty acid content is an important factor in the beef meat industry (Frank et al., 2016; Melton et al., 1982). The type and amount of fatty acids in beef meat have a great effect on quality perception and sensory characteristics, such as taste, tenderness, and flavor (Enser et al., 1996; Frank et al., 2016; Hocquette et al., 2014).

Fatty acids are categorized into saturated fatty acids (SFA) and unsaturated fatty acids (UFA). The SFAs are composed of single bond fatty acid chains, and therefore are usually solids room temperature. On the other hand, UFAs are generally liquids at room temperature because their molecular structure is not linear. Moreover, a previous study reported that the UFAs have a key role in meat flavor (Elmore et al., 1999). In another study, the fatty acid and amino acid characteristics of cattle breeds, including Hanwoo were reported (Hwang and Joo, 2017). However, a comparison of these characteristics between Hanwoo and Jeju black cattle was not performed. Through identification of differences between these two Korean traditional cattle breeds the quality of Korean beef meat production can be enhanced. In this study, we examined the fatty acid and amino acid characteristics of Hanwoo and Jeju black cattle beef and suggest the unique nutritional characteristics of Jeju black cattle beef that have made it a popular meat choice in Korea.

Materials and Methods

Meat samples

A total of 62 cattle of the Hanwoo (n=28; females (F)=11, castrated males (CM)=16), Jeju black cattle (n=25; F=8, CM=17), and Wagyu (CM=10) breeds were used in this study. Hanwoo and Jeju black cattle were raised in the same farm and same feeding condition and slaughtered on Jeju Island. After slaughter, the longissimus dorsi (LD) muscles were sampled and cut into 2.5 cm thick steaks. The muscle samples were vacuum-packed and stored at 4°C until 41 days postmortem. Wagyu beef was commercial meat imported from Australia and also vacuum-packed and stored at 4°C until 41 days postmortem.

Fatty acids and amino acids analysis

To compare the nutritional content, fatty acid and amino acid composition was measured. The fatty acids and amino acids were measured by gas chromatography-flame ionization detector (GC). A total of 37 fatty acids were measured using 25 g of muscle collected from each animal. The samples were methylated with 14% BF3-Methanol and diluted using 1 mL isooctane. The column used was 100 mm×0.25 mm×0.2 μm (Supelco TMSP-2560, Sigma-Aldrich®, USA). The carrier gas was nitrogen at 0.8 mL/min. The injector and the detector were tested at 240°C and 285°C each. The split ratio was varied between 100 and 1. The standard solution of fatty acids was a 0.1 g fatty acid methyl ester mixture (SUPELCOTM 37Component FAME Mix, Bellefonte, PA, USA) diluted to 100 mg/mL in isooctane. The GC retention time of the standard solution is presented in Table S1 and Table S2.

Statistical analysis

The association between cattle traits were measured using the general linear model (GLM) procedure (SAS; SAS Institute, Inc., USA). To compare the mean values between the cattle breeds, Duncan’s multiple range test was used. A value of p<0.05 was considered statistically significant.

Results and Discussion

In this study, we performed fatty acid composition analyses of Hanwoo, Jeju black cattle, and Wagyu breed using a GC method. The fatty acids compositions are presented in Table 1. Palmitic acid showed a significant difference between Hanwoo and Jeju black cattle. Hanwoo beef had much more palmitic acid than Jeju black cattle (p<0.001). In a previous study, palmitic acid, an SFA, had a negative effect on beef meat flavor (Westerling and Hedrick, 1979). Consumers prefer the good flavor of fatty acids in beef fat marble (Kim et al., 1999). Therefore, Jeju black cattle with relatively less palmitic acid, is a popular choice of consumers. There was a significant difference in oleic acid and linoleic acid among breeds (p<0.05). Jeju black cattle showed the highest proportion of oleic acid and contained more oleic acid and linoleic acid than Hanwoo. These fatty acids are representative fatty acids in beef meat (Dryden and Maechello, 1970; Enser et al., 1996; Westerling and Hedrick, 1979). Oleic acid has been reported to have a role in good meat flavor and savory taste (Dryden and Maechello, 1970). The savory taste and flavor are important traits for meat consumers, thus a rich oleic acid content can make meat taste better.

Table 1. Comparison to fatty acids composition between Jeju Black, Hanwoo and Wagyu cattle
Fatty acids Hanwoo Jeju Black cattle Wagyu (n=10) Significance1)
Female (n=11) Castrated male (n=16) Female (n=8) Castrated male (n=17)
C14:0 (Myristic acid) 3.30±0.692) 3.50±0.91 2.35±0.25 2.38±0.56 3.36±0.34 ns
C14:1 (Myristoleic acid) 0.91±0.47 0.99±0.42 1.06±0.61 0.93±0.04 1.03±0.21 ns
C15:0 (Pentadecanoic acid) 0.25±0.05 0.20±0.08 0.00±0.00 0.22±0.10 0.13±0.11 ns
C16:0 (Palmitic acid) 28.74±2.29a 26.83±1.86ab 21.23±1.87b 22.52±1.41b 24.80±0.29b ***
C16:1 (Palmitoleic acid) 4.10±0.49 4.37±0.85 5.07±2.16 4.45±1.07 5.45±1.40 ns
C17:0 (Heptadecanoic acid) 0.66±0.18 0.30±0.25 0.72±0.42 0.39±0.20 0.80±0.21 ns
C17:1 (Heptadecenoic acid) 0.59±0.06 0.82±0.08 0.94±0.12 0.64±0.07 0.67±0.03 ns
C18:0 (Stearic acid) 11.13±0.66 10.37±0.99 8.44±1.73 9.45±1.79 10.05±1.82 ns
C18:1n-9 (Cis-Oleic acid) 47.20±4.03b 49.75±3.14ab 56.34±5.66a 53.95±4.48a 49.91±1.99ab *
C18:2n-6 (Cis-Linoleic acid) 1.95±0.48b 1.94±0.39b 2.56±0.46a 2.66±0.49a 2.62±0.45a *
C20:0(Arachidic acid) 0.04±0.00 0.02±0.00 0.00±0.00 0.00±0.00 0.00±0.00 ns
C18:3n-6(y-Linolenic acid) 0.05±0.01 0.03±0.01 0.00±0.00 0.03±0.01 0.00±0.00 ns
C18:3n-3(Linolenic acid) 0.10±0.03 0.09±0.01 0.00±0.00 0.13±0.05 0.14±0.06 ns
C20:1 (Cis-11-Eicosenoic acid) 0.36±0.23 0.41±0.11 0.47±0.07 0.61±0.29 0.24±0.01 ns
C20:2 (Cis-11,14-Eicosadienoic Acid) 0.00±0.00 0.00±0.00 0.00±0.00 0.65±1.46 0.00±0.00 ns
C20:3n-6 (Cis-8,11,14-Eicosatrienoic acid) 0.15±0.06 0.13±0.08 0.37±0.21 0.28±0.02 0.24±0.03 ns
C20:4n-6(Arachidonic acid) 0.47±0.32 0.25±0.23 0.45±0.40 0.71±0.68 0.56±0.05 ns
SFA (%) 44.22±3.23a 41.31±3.11a 32.74±4.17b 35.09±3.76b 39.28±3.62ab ***
MUFA (%) 53.16±3.16b 56.34±2.85b 63.88±3.79a 60.58±3.98a 57.30±3.49ab **
PUFA (%) 2.62±0.66b 2.35±0.67b 3.38±0.68a 4.33±1.15a 3.42±0.69a *

1) Significance levels for breeds: ns, not significant, * p<0.05, ** p<0.01, *** p<0.001.

2) SMeans±SD.

a,b SDifferent superscript letters indicate significant differences between breeds at p<0.05.

SFA, saturated fatty acids; MUFA, mono-unsaturated fatty acids; PUFA, poly-unsaturated fatty acids.

Download Excel Table

Linoleic acid was reported to cause a negative flavor in meat (Westerling and Hedrick, 1979). Jeju black cattle beef may be less flavorful than Hanwoo meat because of linoleic acid, but the absolute amount of linoleic acid is less than the palmitic acid amount. Therefore, its effect to decrease flavor in Jeju black cattle beef could be expected to be small. Jeju black cattle showed a lower proportion of SFAs than Hanwoo (p<0.001). SFAs are known to be the main culprit in hyperlipidemia and hypercholesterolemia (Bingham et al., 2002; Micha and Mozaffarian, 2010; Mozaffarian et al., 2010). These conditions are reported to cause cardiovascular disease and diabetes (Bingham et al., 2002; Micha and Mozaffarian, 2010). Therefore, lower proportions of SFAs are more preferable. In addition, the consumers’ preference has changed from flavor to health (Joo et al., 2017). Therefore, the lower SFAs in Jeju black cattle beef are likely to be preferred by consumers.

In contrast to the SFA ratio, the UFA ratio, including mono-UFA (MUFA) and poly-UFA (PUFA) was higher in Jeju black cattle than Hanwoo (MUFA: p<0.01, PUFA: p<0.05). The UFA ratio is also known to be associated with better health (Cross et al., 2007; Kontogianni et al., 2008). In previous studies, a high UFA ratio prevented cardiovascular disease, a common disease with a high mortality rate (Kim et al., 2018; Rawshani et al., 2017). Hence, the Jeju black cattle could be a better choice for consumers who consider health a priority.

To compare the nutritional characteristics between Hanwoo, Jeju black cattle, and Australian Wagyu breed, we tested the amino acid composition of meat using GC. The amino acid composition results are presented in Table 2. The amino acid composition was significantly different among breed. Jeju black cattle had higher amounts of alanine than Hanwoo (p<0.05). The amino acid alanine is associated with a sweet taste in meat (Shallenberger and Acree, 1967), so Jeju black cattle beef could be perceived to be sweeter than Hanwoo meat. Glutamic acid was higher in Hanwoo than Jeju black cattle (p<0.01). Glutamic acid is known for its umami taste, the fifth basic taste (Kirimura et al., 1969; Lindemann, 1996; Nelson et al., 2002). Therefore, the consumers might perceive more umami taste in Hanwoo beef.

Table 2. Comparison to amino acids composition between Jeju Black, Hanwoo and Wagyu cattle
Amino acids Hanwoo Jeju Black cattle Wagyu (n=10) Significance1)
Female (n=11) Castrated male (n=16) Female (n=8) Castrated male (n=17)
Alanine 16.97±1.27b2) 22.54±2.98a 22.41±3.49a 23.71±3.98a 22.89±3.18a *
Asparagine 2.05±0.83 1.32±0.37 1.42±0.07 1.80±0.51 1.90±0.24 ns
Aspartic acid 1.76±0.06a 1.64±0.11a 0.00±0.00b 1.25±0.31b 0.05±0.02b **
Cysteine 0.98±0.03b 0.46±0.03b 1.87±0.14a 0.58±0.01b 0.20±0.01b *
Glutamic acid 4.01±1.16a 2.39±0.42b 1.68±0.09b 2.08±0.95b 2.02±0.36b **
Glutamine 11.70±1.50b 25.76±2.62a 33.86±8.41a 25.47±7.34a 25.76±2.62a *
Glycine 5.81±0.20 5.80±1.07 5.05±0.40 6.26±1.64 5.61±1.14 ns
Histidine 3.14±0.45 2.59±0.52 3.53±1.20 3.34±1.49 3.51±1.22 ns
Isoleucine 5.16±0.43a 2.96±0.74b 2.20±0.38b 2.72±0.73b 2.67±0.56b ***
Leucine 11.07±0.72a 6.22±1.36b 4.55±0.65b 5.59±1.61b 6.05±1.20b ***
Lysine 1.64±0.17b 1.64±0.31b 2.68±0.37a 2.18±0.89ab 2.02±0.37ab *
Methionine 5.90±0.28a 3.80±0.45b 2.47±0.30c 3.29±0.93bc 3.67±0.43b ***
Ornithine 1.48±0.44 1.18±0.18 1.87±1.15 0.93±0.39 1.73±0.25 ns
Phenylalanine 7.27±0.39a 4.64±0.75b 3.65±0.62b 4.60±1.00b 4.64±0.78b **
Proline 1.95±0.04b 2.61±0.23a 2.42±0.33ab 2.65±0.33a 2.63±0.31a *
Serine 6.05±0.07a 3.94±0.60b 2.62±0.01b 3.81±1.39b 3.91±0.89b **
Threonine 4.98±0.17a 2.82±0.68b 1.95±0.28b 2.74±1.00b 2.84±0.88b **
Tyrosine 1.04±0.13b 2.66±0.63a 2.32±0.06a 2.41±0.64a 2.69±0.76a **
Valine 6.32±0.82a 4.50±0.92ab 3.14±0.65b 3.93±1.42b 4.43±1.42ab *

1) Significance levels for breeds: ns, not significant, * p<0.05, ** p<0.01, *** p<0.001.

2) Means±SD.

a,b Different superscript letters indicate significant differences between breeds at p<0.05.

Download Excel Table

The amino acids imparting bitter tastes, including valine, leucine, isoleucine, and methionine were higher proportions in Hanwoo than in Jeju black cattle (p<0.05, p<0.001, p<0.001 and p<0.001 each). Compared to the other basic tastes of sweet, sour and salty, the bitter taste remains longer (Kato et al., 1989; Nishimura and Kato, 1988; Solms, 1969). In addition, a previous study showed that people were displeased by a single bitter taste (Drewnowski and Gomez-Carneros, 2000). Therefore, Jeju black cattle could be more preferable than Hanwoo beef.

Conclusion

Jeju black cattle had much more UFA and savory amino acids, including alanine, than Hanwoo and Wagyu breeds. The UFAs, such as oleic acid, provided rich favor. In addition, these UFAs could reduce blood cholesterol. The savory amino acids, such as alanine may affect consumer preference because of the savory taste they impart to beef.

Taken together, our results suggest that Jeju black cattle beef had higher savory flavor and umami taste which affected consumers preference for the meat.

Notes

Conflict of Interest

The authors declare no potential conflict of interest.

Acknowledgements

This research was supported by the 2018 scientific promotion program funded by Jeju National University. We are grateful to Sustainable Agriculture Research Institute (SARI) in Jeju National University for providing the experimental facilities.

Notes

Author Contributions

Conceptualization: Park SP. Methodology: Ko KB. Writing - original draft: Lee SH, Kim CN. Writing - review & editing: Lee SH, Kim CN, Ko KB, Park SP, Kim HK, Kim JM, Ryu YC.

Notes

Ethics Approval

This article does not require IRB/IACUC approval because there are no human and animal participants.

Supplemenrary Materials

Supplementary Tables

kosfa-39-3-402-suppl1.pdf

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