• Nutrition Research and Practice
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• 제16권3호
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• pp.354-365
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• 2022

BACKGROUND/OBJECTIVES: Understanding the mechanism of chewing and swallowing food is important when creating a proper diet for older adults. This study investigated whether texture-modified model foods can reduce the difference in chewing and swallowing parameters between healthy community-living young and older adults. SUBJECTS/METHODS: In total, 35 older and 20 young adults (mean age: 75 and 25 years, respectively), matched for sex and number of teeth, were recruited and their unstimulated salivation and tongue pressure were measured. Simultaneous assessment of chewing and swallowing characteristics was conducted using surface electromyography and a videofluoroscopic swallowing study while the participants ingested 8 g of model food with one to four levels of hardness. RESULTS: The average tongue pressure and salivation among older adults were 61% and 49.7%, respectively, of the corresponding values observed in young adults. The older adult group used significantly (P < 0.05) increased muscle force with more chewing cycles (P < 0.05) than the young adult group, which was maintained even when consuming foods with the lowest hardness, although without chewing. However, the age effect on oral processing time existed only for the hardest foods. Swallowing difficulties among older adults were demonstrated by the significant increase in vallecula aggregation time. The total food intake duration was significantly (P < 0.05) longer in older adults than in young adults, regardless of food hardness. CONCLUSIONS: There were measurable differences in the process of chewing and swallowing food between young and older adults, which can be improved with food hardness control. Adjusting food hardness may help food intake in healthy older adults.

• Asian-Australasian Journal of Animal Sciences
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• 제20권7호
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• pp.1127-1134
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• 2007

Gels were made from surimi-like pork (SLP) made from muscles obtained at 1, 24 and 72 h post-mortem. The SLP from pre-rigor muscle had higher pH and moisture percentage compared to in- or post-rigor muscles. Also, SLP from pre-rigor muscle showed higher concentration of water-soluble protein that was washed out during the process. Gel from post-rigor muscle exhibited higher a* and b* value, and also resulted in higher Chroma and lower hue values. The dark color of gel from post-rigor muscle was related to higher concentration of sarcoplasmic protein in SLP and denser structure in the gel matrix. SDS-PAGE showed higher intensity of the phosphorylase in the sarcoplasmic protein fraction from pre-rigor muscle. Gel from post-rigor muscle showed higher hardness and sensory firmness, and the greater firmness was related to higher concentration of protein in SLP, and a compact network with smaller pockets in the gel matrix.

• 한국수산과학회지
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• 제24권6호
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• pp.405-412
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• 1991

Whitefish와 Burbot는 북미지역, 유럽 등지에서 비교적 널리 이용되고 있는 담수어종이지만 Whitefish는 조직이 연하여 가공중 부스러지기 쉽다는 점이 문제가 되고 있으며, 이와는 대조적으로 Burbot육은 끈적한 점액이 어피를 둘러싸고 있어 이용이 제한되고 있는 외에 가공저장중에 조직이 tough해지는 결점이 있다. 따라서 본 실험에서는 이들의 조직상의 제 문제를 개선함으로써 두 of종의 가공성을 높이고 나아가 상품적 가치를 제고할 목적으로 이들의 texture에 영향을 미친다고 생각되는 각종 인자들을 살펴보았다. 두 어종의 어육을 fillet로 하여 대조군과 인산염 완충용액을 high pressure injection법으로 처리한 군의 pH, 수분 함량, Total collagen량의 차이를 검토하였고 아울러 $-12^{\circ}C$에서 3개월 간 저장한 후의 이들의 변화를 살펴보았으며, 이들 제 인자들이 Instron texturometer로써 측정한 texture와 어떻게 관련되어 지는지를 다중 회귀방정식을 이용하여 분석하였다. pH는 인산염 처리구가 대조구보다 다소 높았다. 3개월 저장으로 두 어종 모두 pH와 수분함량이 감소하였다. Instron texturometer으로 측정한 texture의 값과 이들 제 인자들 사이의 상관관계는 조직이 약한 whitefish에서는 상관계수가 낮아 특정인자가 두드러진 영향을 미친다고 보기는 어려웠으나 조직이 단단한 burbot육은 이들 인자 중 pH가 비교적 상관계수가 높게 나타났다.

• 한국가금학회지
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• 제26권3호
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• pp.195-201
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• 1999

The present study was conducted to investigate the effects of dietary supplemental dry powder of chinese medicine refuse (CMR) on the growth performance and physiological status of broiler chicks. The treatments consisted of corn-soybean meal control diet, CMR 4 and 8% diets. A total of 120 Arbor Acre broiler chicks were randomly allotted to 12 pens ; four pens per treatment and 10 birds per pen. The body weight gain and feed intake did not show ant differences among the treatment groups, but feed conversion was significantly higher (P〈0.05) in CMR 8% group than that of the control group. Hunt L and b did not show ant differences among the treatment groups, but hunt a was darker (P〈0.05) in CMR 4 and 8% group than that of the control group. The blood concentrations of total protein, sugar, glutamic-oxaloacetic-transaminase (GOT), glutamic-pyruvic-transaminase (GPT) Hemogloben were not different among the treatment groups. The pH of thigh muscle were lower in CMR 4 and 8% groups than that of the control group, but crude fat, crude ash of thigh muscle and bone hardness in brolier chicks did not show ant differences among the treatment groups. The saturated fatty acid content of the thigh muscle tende to decrease dietary CMR increased.

• Asian-Australasian Journal of Animal Sciences
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• 제19권11호
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• pp.1658-1664
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• 2006

The objective of this study was to investigate the effects of sodium alginate (SA) and pressurization levels on pH, water-binding and textural properties of pork muscle gels (PMG) containing salt. Ground lean pork with 1.0% NaCl and a given amount of SA (0.25, 0.5, 0.75 and 1.0%, respectively), was pressurized to 100, 200 or 300 MPa and subsequently gelled by heating. Results showed that addition of SA into pork muscle enhanced water-holding capacity (WHC) of PMG (p<0.05) as SA increased from 0.25% to 1.0%, with pH slightly increased (p>0.05). A decrease (p<0.05) was observed in all textural parameters (hardness, cohesiveness, springiness and chewiness). Pressurization had no effect on the tendency of WHC to increase or the decrease of the textural parameters. However, the effectiveness of pressurization to enhance textural properties of PMG was significant at some SA levels, especially ${\geq}200MPa$ and at ${\leq}0.75%$ SA levels. Different combinations of pressure and SA levels could bring about variation in textural properties of PMG while SA enhanced WHC of pork muscle. The multiformity of the texture will open up a wide range of technological possibilities for the manufacture of pork-based restructured low-fat products.

• 한국축산식품학회지
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• 제32권6호
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• pp.756-762
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• 2012

The pre-rigor salting effects on physicochemical properties of ground duck breast muscle were evaluated in this study. The pre-rigor salting treatments were prepared within 30 min after slaughter, the duck breast muscles after post mortem 48 h were used to prepare the post-rigor treatments. The pre-rigor salting treatment had significantly higher pH value than post-rigor salting treatment (p<0.001), and all pre-rigor salting treatments showed a significant higher pH value. As a result, the pre-rigor salting treatment showed increased water holding capacity and decreased cooking loss compared to those in the post-rigor salting treatment. No significant differences in redness and yellowness were observed among the treatments (p>0.05). The increased solubility of salt-soluble proteins in the pre-rigor salting treatment leads to increase the hardness, gumminess, and chewiness. Also, the pre-rigor salted duck breast muscle had similar textural properties compared to those of post-rigor duck breast muscle containing sodium tri-polyphosphate (STPP). The 2-thiobarbituric acid (TBA) values of all treatments were ranged from 0.121 to 0.177 mg/kg. The lowest TBA value was observed for post-rigor duck breast muscle containing STPP, however, pre-rigor salting did not influence lipid oxidation of ground duck breast muscle. Therefore, the pre-rigor salting method, especially a single addition of sodium chloride to pre-rigor muscle, is more efficient method for improving cooking loss.

• 한국수산과학회지
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• 제49권3호
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• pp.270-276
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• 2016

This study investigated the sensory characteristics (texture, odor, taste and color) of jerky produced from ground sea rainbow trout (SRT) Oncorhynchus mykiss frame muscle (FM). The hardness of the ground SRT-FM jerky was 453.9±91.0 g/cm², which was lower than that of commercial animal jerky (893.5±404.6 g/cm²) and commercial fish jerky (1,394.4±363.5 g/cm²). The difference in the hardness values of the ground SRT-FM jerky and commercial animal jerky was not significant. The volatile basic nitrogen content of the ground SRT-FM jerky was 48.3±1.6 mg/100 g, which was higher than that of commercial fish jerky (21.6±6.2 mg/100 g) and commercial animal jerky (18.2±6.3 mg/100 g). However, the fish odor of the ground SRT-FM jerky was masked by the presence of various additives. The hydrophilic and lipophilic browning indices of the ground SRT-FM jerky were higher than those of the commercial jerky. The total taste value of the ground SRT-FM jerky was 169.0, and the major amino acids were glutamic acid and aspartic acid. These results suggest that ground SRT-FM jerky would be acceptable to consumers.

• Animal Bioscience
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• 제34권4호
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• pp.652-661
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• 2021

Objective: Wooden breast (WB) is a novel myopathy affecting modern broiler chickens, which causes substantial economic losses in the poultry industry. The objective of this study was to evaluate the effect of WB abnormality on meat quality, redox status, as well as the expression of genes of the nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway. Methods: A total of 80 broilers (Ross 308, 42 days of age, about 2.6 kg body weight) raised at Jiujin farm (Suqian, Jiangsu, China) were used. Twelve unaffected (no detectable hardness of the breast area) and twelve WB-affected (diffuse remarkable hardness in the breast muscle) birds were selected from the commercial broiler farm according to the criteria proposed by previous studies. Results: The results indicated that WB showed histological lesions characterized by fiber degeneration and fibrosis, along with an increase of muscle fiber diameter (p<0.05). Moreover, higher pH value, lightness, yellowness, drip loss and cooking loss were observed in the WB group (p<0.05). Compared with the normal breast (NOR) group, the WB group showed higher formation of reactive oxygen species (p<0.05), increased level of oxidation products and antioxidant activities (p<0.05), accompanied with mitochondrial damages and lower mitochondrial membrane potential (p<0.05). Meanwhile, the relative mRNA expressions of Nrf2 and its downstream antioxidant genes including heme oxygenase-1, NAD(P)H qui none dehydrogenase 1, glutathione peroxidase, superoxide dismutase, and glutamate-cysteine ligase were higher than those of the NOR group (p<0.05). Conclusion: In conclusion, WB myopathy impairs meat quality by causing oxidative damages and mitochondrial dysfunction in broilers, even though the activated Nrf2/antioxidant response element pathway provides protection for the birds.

• 한국수산과학회지
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• 제48권1호
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• pp.16-25
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• 2015

This study compared the food quality of salmonid fishes according to the species, country of origin, and separated part, such as fillet and frame. The proximate composition of chum salmon from Norway (CS-N) was 74.4% moisture, 19.5% crude protein, 4.2% crude lipid, and 1.2% ash. These values were within roughly 1% for the other salmon species. There was no significant difference (at P<0.05) in the Hunter a value of salmon muscle according to sepatated parts. However, there was a significant difference (P<0.05) in Hunter a value of salmon muscle according to the species and country of origin. There were significant differences in odor intensity and hardness of the salmon according to the species. The major free amino acid in all of the salmon muscles was anserine, which ranged from 61.3 to 73.0%. The taste value was the highest for salmon imported from Alaska (CS-A), followed by pink salmon, CS-N, and muscle separated from the frame (AS-C). In the taste value of all salmon muscles, the major amino acid was glutamic acid. The total amino acid content of salmon muscles ranged from 18.36 to 19.64 g/100 g, and the major amino acids were glutamic acid and aspartic acid. There were differences in the mineral contents, including Ca, P, K, and Fe, and fatty acid composition of salmon muscle according to species.

• 한국축산식품학회지
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• 제35권5호
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• pp.577-584
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• 2015

This study was conducted to evaluate the effect of pre-rigor salting level (0-4% NaCl concentration) on physicochemical and textural properties of pre-rigor chicken breast muscles. The pre-rigor chicken breast muscles were de-boned 10 min post-mortem and salted within 25 min post-mortem. An increase in pre-rigor salting level led to the formation of high ultimate pH of chicken breast muscles at post-mortem 24 h. The addition of minimum of 2% NaCl significantly improved water holding capacity, cooking loss, protein solubility, and hardness when compared to the non-salting chicken breast muscle (p<0.05). On the other hand, the increase in pre-rigor salting level caused the inhibition of myofibrillar protein degradation and the acceleration of lipid oxidation. However, the difference in NaCl concentration between 3% and 4% had no great differences in the results of physicochemical and textural properties due to pre-rigor salting effects (p>0.05). Therefore, our study certified the pre-rigor salting effect of chicken breast muscle salted with 2% NaCl when compared to post-rigor muscle salted with equal NaCl concentration, and suggests that the 2% NaCl concentration is minimally required to ensure the definite pre-rigor salting effect on chicken breast muscle.