• 한국축산식품학회지
• /
• 제41권4호
• /
• pp.650-663
• /
• 2021

The objective of this study was to examine the relationship between meat quality attributes and the changes of sarcoplasmic protein acetylation and myofibrillar protein acetylation in lamb longissimus thoracis et lumborum muscles at different postmortem phases. Protein acetylation, color, pH, shear force, myofibril fragmentation index and cooking loss were measured. The total level of acetylated sarcoplasmic proteins showed a negative relation with pH, a positive relation with a^*, b^* and cooking loss at the pre-rigor phase. Sarcoplasmic proteins acetylation affected postmortem pH by regulating glycolysis, which in turn affects color and cooking loss. The total level of acetylated myofibrillar proteins showed a positive relation with shear force at the pre-rigor phase. Myofibrillar proteins acetylation affected meat tenderness by regulating muscle contraction. This study indicated that acetylation played a regulatory role of meat color, water-holding capacity, and tenderization process at early postmortem.

• 한국수산과학회지
• /
• 제19권5호
• /
• pp.477-484
• /
• 1986

The interaction of myofibrillar protein with lipid or oxidized lipid was considered to be mostly contributing to the drop of digestibility of fish meat products. The digestibility of myofibrillar protein was $92.11\%$ for flounder and $88.04\%$ for hairtail fish, repectively, and as a rule it decreased as both the amount of lipid and reaction time increased. It also decreased with increase in the amount of added linoleate and oxidized linoleate. However, when the reaction continued for 6 hours or more the digestibility rather increased, which was provably due to the unfolding of protein structure. The hot air dried hairtail fish showed the lowest C-PER values among all dried fish products. The protein quality of flounder, hairtail fish and their dried ones except hot air dried ones measured by C-PER procedure were superior to that of ANRC casein. DC-PER values of all samples were greater than those of C-PER values and the greater discrepancies were noted in hairtail fish (fatty fish) products which possessed the lower in vitro protein digestibilities. Predicted diegstibilities, which were calculated using amino acid profiles, of all samples except raw ones were overestimated in comparison with in vitro protein digestibilities. From the observations so far, formation of complex of lipids and protein was thought to be the most important factor in lowering protein digestibility of the dried fish meat products.

• 한국축산식품학회지
• /
• 제43권2호
• /
• pp.305-318
• /
• 2023

This study investigated the protein digestibility of chicken breast and thigh in an in vitro digestion model to determine the better protein sources for the elderly in terms of bioavailability. For this purpose, the biochemical traits of raw muscles and the structural properties of myofibrillar proteins were monitored. The thigh had higher pH, 10% trichloroacetic acid-soluble α-amino groups, and protein carbonyl content than the breast (p<0.05). In the proximate composition, the thigh had higher crude fat and lower crude protein content than the breast (p<0.05). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of myofibrillar proteins showed noticeable differences in the band intensities of tropomyosin α-chain and myosin light chain-3 between the thigh and breast. The intrinsic tryptophan fluorescence intensity of myosin was lower in the thigh than in the breast (p<0.05). Moreover, circular dichroism spectroscopy of myosin revealed that the thigh had higher α-helical and lower β-sheet structures than the breast (p<0.05). The cooked muscles were then chopped and digested in the elderly digestion model. The thigh had more α-amino groups than the breast after both gastric and gastrointestinal digestion (p<0.05). SDS-PAGE analysis of the gastric digesta showed that more bands remained in the digesta of the breast than that of the thigh. The content of proteins less than 3 kDa in the gastrointestinal digesta was also higher in the thigh than in the breast (p<0.05). These results reveal that chicken thigh with higher in vitro protein digestibility is a more appropriate protein source for the elderly than chicken breast.

• Asian-Australasian Journal of Animal Sciences
• /
• 제20권8호
• /
• pp.1292-1296
• /
• 2007

To investigate the gel properties of surimi-like materials (SLM) made from pig heart (PH), psoas major muscle (PM) and semimembranosus muscle (SM) of pigs, the three muscles were diced, chopped and washed with 25 mM sodium phosphate buffer (pH 7.0) to extract myofibrillar protein. SLM from SM had significantly (p<0.05) higher moisture content and lower crude protein content compared with PH and PM samples. The cooked SLM from PH was darker than that from PM and SM. Gel from PH had significantly (p<0.05) lower L* and hue values, and higher b* and chroma values compared to gels from PM and SM. The cooked SLM from PH had poor water-holding capacity (WHC) resulting in higher cooking loss. SDS-PAGE showed that the bands of myosin and tropomyosin/troponin had reduced staining intensity in the PH sample, and some unidentified bands that were not in PM and SM samples were observed in PH samples.

• 한국식품영양학회지
• /
• 제11권4호
• /
• pp.409-415
• /
• 1998

This study was carried out to investigate the effects of freezing temperature on quality of vacuum packaging freezed beef. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -20$^{\circ}C$ were 5.23% and 5.17% to 60 days respectively, were increased significantly during freezing. The cooking loss of water bath and pan were increased significantly during freezing than the beginning of freezing, but were no different between -3$^{\circ}C$ and -20$^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -20$^{\circ}C$ freezing was higher than -3$^{\circ}C$freezing. The water soluble protein extractability was increased during freezing higher than during freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ freezing was higher than -20$^{\circ}C$ freezing, the 15 days storage of -3$^{\circ}C$ freezing was highest to 96%. The shear force value was not change during freezing, the myofibrillar fragmentation index during freezing was higher than the beginning of freezing, but was not change during freezing. The pH was decreased to freezing 45 days, after that increased.

• Fisheries and Aquatic Sciences
• /
• 제2권2호
• /
• pp.161-166
• /
• 1999

The rigor-mortis progress of cultured olive flounder spiked at the brain started much faster than that of wild one. They attained full rigor state after 30 hrs at $0^{\circ}C$, 36 hrs at $5^{\circ}C$ and 50 hrs at $10^{\circ}C$ in the cultured flounder, while after 36 hrs at $0^{\circ}C$, 50 hrs at $5^{\circ}C$, and 60 hrs at $10^{\circ}C$ in the wild. ATP concentration in the muscle was around $5.9\mu mol/g$ for wild and $6.2\mu mol/g$ for cultured flounder. ATP breakdown progressed rapidly in $0^{\circ}C$ samples, followed by $5^{\circ}C$ and $10^{\circ}C$ samples. $Mg^{2+}$-ATPase activity of myofibrillar protein in the presence of 0.25mM CaCb was higher in cultured myofibri1lar protein than in wild one. $Mg^{2+}$-ATPase activities of myofibrillar protein increased during storage in samples stored at $0^{\circ}C$ and $5^{\circ}C$ while decreased in samples stored at $10^{\circ}C$. The level of breaking strength of muscle immediately after death was higher in the wild muscle than in the cultured muscle. The breaking strength reached maximum level at 10 hrs after death in both samples.

• Animal Bioscience
• /
• 제34권11호
• /
• pp.1859-1869
• /
• 2021

Objective: The effects of a crude protease extracted from Cordyceps militaris (CM) mushrooms on the postmortem tenderization mechanism and quality improvement in spent hen breast were investigated. Methods: Different percentages of the crude protease extracted from CM mushrooms were introduced to spent hen breast via spray marination, and its effects on tenderness-related indexes and proteolytic enzymes were compared to papain. Results: The results indicated that there was a possible improvement by the protease extracted from CM mushroom through the upregulation of endogenous proteolytic enzymes involved in the calpain system, cathepsin-B, and caspase-3 coupled with its nucleotide-specific impact. However, the effect of the protease extracted from CM mushroom was likely dose-dependent, with significant improvements at a minimum level of 4%. Marination with the protease extracted from CM mushroom at this level led to increased protein solubility and an increased myofibrillar fragmentation index. The sarcoplasmic protein and collagen contents seemed to be less affected by the protease extracted from CM mushroom, indicating that substrate hydrolysis was limited to myofibrillar protein. Furthermore the protease extracted from CM mushroom intensified meat product taste due to increasing the inosinic acid content, a highly effective salt that provides umami taste. Conclusion: The synergistic results of the proteolytic activity and nucleotide-specific effects following treatments suggest that the exogenous protease derived from CM mushroom has the potential for improving the texture of spent hen breast.

• 한국수산과학회지
• /
• 제19권4호
• /
• pp.333-338
• /
• 1986

우리 나라 전역에 걸쳐 널리 분포하고 있는 붕어와 가물치의 영양학적 기초자료를 제공하기 위하여 단백질, 구성아미노산 및 유리아미노산의 조성을 분석하고, 육단백질중 근형질단백질과 근원섬유단백질은 SDS-polyacrylamide gel 전기영동하여 그 구성 sub-unit를 검토하였다. 가물치는 붕어에 비하여 조단백질의 함량이 $3\%$가량 높았으며 Ex 분의 함량 또한 월등히 많았다. 육 단백질을 구성하는 단백질 조성은 붕어의 경우 근형질 단백질이 $32.6\%$, 근원섬유 단백질이 $62.0\%$, 알칼리가용성 단백질이 $4.9\%$, 기질 단백질이 $0.6\%$이었으며, 가물치는 근형질 단백질이 $30.7\%$, 근원섬유 단백질이 $64.1\%$, 알칼리가용성 단백질이 $4.7\%$, 기질 단백질이 $0.4\%$를 차지하고 있었다. 근형질 단백질과 근원섬유 단백질 분획의 일부에 대하여 구성 subunit를 분석한 결과, 붕어의 근형질단백질은 10개의 subunit로 구성되어 있었고, 가물치는 12개의 subunit로 구성되어 있었다. 한편 근원직유 단백질은 붕어가 19개의 subunit이었으며, 가물치는 18개 subunit로 이루어져 있었다. 단백질의 구성아미노산 조성은 lysine과 glutamic acid를 제외하고는 대체로 붕어와 가물치가 비슷한 편이었으며, glutamic acid, lysine, aspartic acid 및 arginine이 전체 구성아미노산의 약 $46\%$를 차지하고 있었다. 또한 유리아미노산조성에 있어서 붕어는 histidine이 전체유리아미노산의 $52.2\%$를 차지하고 있었으며, 가물치는 glutamic acid, glycine와 taurine이 전체유리아미노산의 약 $84.5\%$를 차지하였다. 그리고 총 유리아미노산의 양에 있어서 가물치는 붕어의 약 6.2배에 달하였다.

• 한국수산과학회지
• /
• 제15권2호
• /
• pp.123-136
• /
• 1982

방어의 배육 보통육과 측육 혈합육을 $2^{\circ}C$에 보장하여 두고 선도변화 총계별로 단백질의 조성과 각축의 구성 및 유리아미노산의 조성을 분석하였으며, 건향질단백질과 근원섬유단백질에 대하여는 구성단백질의 분포변화를 확인하기 위하여 $NaDodSO_4$변한 다음, polyacrylamide겔 전기영동상을 비교 해석함으로써 적색육어류의 선도변화와 보통육 및 혈합육의 단백질조성 변화와의 관련성을 검토하였다. K-값과 휘발성염기질소 및 pH값으로 판정했을 때, 혈합육은 보통육에 비하여 선도변화가 빨랐다. 사후 선도변화와 더불어 근원질단백질과 노원섬유단백질은 감소하는 반면, 세포내잔사단백질은 상대적으로 증가하였으며, 이러한 변화는 보통육에 비하여 혈합육이 훨씬 심한 편이었다. Sodium dodecyl sulfate 화한 단백질을 polyacrylamide겔 전기영동함으로 분석한 결과, 보통육의 근원질단백질은 16개 성분, 그리고 혈합육의 근원질단백질은 12개 성분으로 구성되어 있었으며, 보장 10일째부터 보통육의 근원질단백질은에는 41,000dalton과 18,000dalton의 양분이 조금씩 증가하였고, 26,000 dalton과 23,500 dalton 및 23,000 dalton되 각 성분은 점차 감소하였다. 혈합육의 근원질단백질에 있어서는 49,000 dalton의 성분은 감소하였고 47.000 dalton의 성분은 새로이 형성되었으며, 26,000 dalton의 성분은 소감하였다. 근원섬유단백질의 전기영동분석결과에 의하면, 보통육의 근원섬유단백질은 17개 성분, 그리고 혈합육의 근원조직단백질은 16개의 성분으로 구성되어 있었다. 보장 10일에부터 보통육의 근원섬유단백질중에는 40,000 dalton의 성분이 증가하였고, 37,500 dalton의 성분은 점차 감소하였으며, 32,000 dalton의 성분은 새로히 출현하였다. 혈합육의 근원섬유단백질은 보장 9일째부터 58,000 dalton과 64,000 dalton의 성분은 그 농도가 단가하였으며, 17,500의 light chain-2 단백질은 소감하였고, 32,000 dalton의 성분은 새로이 출현하였다. 이 같은 전기영동상의 변화는 근원질단백질이 근원섬유단백질에 비하여 빨랐으며, 근원섬유단백질의 경화에 있어서는 혈합육쪽이 보통육에 비하여 빨랐다. 양 육의 단백질을 구성하는 아미노산을 분석한 결과, 즉살한 방어의 보통육 단백질은 글루탐산, 아스팔트산, 류신. 알기닌, 알라닌 등은 그 양이 어느 정도 많았고, 프롤린과 트?토판은 그 양이 적었으며, 혈합육에 있어서도 비슷한 경형이었다. 그리고 10일이 경과한 보통육에 있어서는 글루탐산과 아스팔트산이 현저히 감소하였으며, 9일이 경과한 혈합육에 있어서는 알라닌, 글리신, 그리고 알기닌이 현저히 감소하였다. 유리아미노산의 조성을 분석 결과, 즉살한 방어의 보통육중에는 히스티딘이 총유리아미노산의 약 $63\%$를, 그리고 혈합육중에는 타우린이 총유리아미노산의 약 $67\%$를 차지하는 양을 보였다. 그리고 $2^{\circ}C$에서 10일이 경과했을 때, 보통육에서는 히스티딘, 발린, 타우린이 증가하였으며, 알라닌, 류신 및 글리신 등은 조금 감소하였다. 같은 온도에서 9일이 경과한 혈합육에서는 타우린, 페닐알라닌, 글리신은 증하였으며, 히스티딘, 알라닌, 세린 등은 감소하였다.

• 한국축산식품학회지
• /
• 제23권2호
• /
• pp.122-127
• /
• 2003

본 연구는 유화형 소시지 제조시 이용되는 원료육에 대해 돼지 심장근으로부터 획득한 근원섬유 단백질 추출물인 수리미 유사물의 대체첨가가 제품의 품질특성에 미치는 영향을 구명하고자 수행하였다. 그 결과, 원료육에 대해 15% 수리미 유사물을 대체한 처리구가 대조구에 비해 가열감량은 유의적(p<0.05)으로 낮게 나타났고, 보수력은 유의적(p<0.05)으로 높게 나타났다. 전단가 및 경도에 있어서도 수리미유사물의 대체처리구가 대조구에 비해 유의적(p<0.05)으로 낮게 나타났다. 육색에 있어 명도(L)는 수리미유사물을 대체한 처리구가 대조구에 비해 유의적(p<0.05)으로 낮게 나타났으며, a, b값은 유의적인 차이가 나타나지 않았다(p>0.05). 한편, 관능검사 결과 대조구와 처리구간에 향미와 불쾌취에 있어 유의적인 차이가 나타나지 않았지만, 전체적인 기호도에 있어 15% 수리미유사물 대체처리구가 유의적(p<0.05)으로 높은 점수를 얻었다. 이상의 결과를 종합해 볼 때, 유화형 소시지제조시 돼지 심장근에서 획득한 근원섬유 단백질 추출물을 원료육 대비 15%까지 대체하더라도 가열감량을 낮춰 제품 수율을 높일 뿐만 아니라 보수력을 높이고 조직감을 부드럽게 하여 기호성을 증진시키는 효과를 얻을 수 있을 것으로 사료된다.