• Preventive Nutrition and Food Science
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• v.4 no.1
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• pp.23-27
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• 1999

To evaluate the quality of fish extracts with spicy vegetables (garlic, onion and ginger) in suppressing fishy oder, fish extracts of crucian carp, loach, bastard halibut and jacopever were processed at 100 $^{\circ}C$ for 6 hours, and their in vitro and in vivo protein qualities were determined . Protein and total lipid contents were closely related to the degree of discarding floated lipid on fish extracts and the kinds of added apicy vegetables . Boiling (10$0^{\circ}C$) , appeared to improve in vitro protein qualities slightly more than hydrocooking (11$0^{\circ}C$), but those with mild processing tended to result in better protein qualities than high temperature cooking (136-14$0^{\circ}C$). Spicy vegetables did not have remarkable effects on improving in vitro protein quality parameters. Fish extracts with 10% ginger were generally higher in in vitro protein quality than with the other vegetables . In spite of higher in vivo protein digestibility of fish extracts containing spicy vegetables processed under mild conditions(10$0^{\circ}C$), PERs of those extracts were not higher htan those of extranct processed at high temperature.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.241-247
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• 1998

Fish extracts were processed at high temperature (136.7 ~14$0^{\circ}C$) for possible use as functional food ingredients. Raw fish meats and those hydrothermal extracts were compared with respect to in vitro and in vivo protein qualities. 95% of fat inraw meats was reduced in extracts but there were not remarkable changes in other macronutrients in freeze-dried extracts. Most of essential amino acids were decreased significantly but two times more proline and glycine were detected in extracts. High temperature cooking resulted 2.1 ~3.7 times of higher total free amino acid content infish extracts compared iwth raw meat, and taurine and glutamic acid were increased especially. Severe protein damages were occurred when invitro protein quality indices such as availblae lysine, hydrophilic browing, trypsin inhibitor formation and in vitro protein digestibility were measured on fish extracts. In vivo protein qualities were also strongly influenced by high temperature ; however rat-body-weight gain was nearly zero during PER assay, and rat PER or NPR of fish extracts were significantly lower (p<0.001) than those of cotnrol (ANRC casein) and original raw fish meats.

• Preventive Nutrition and Food Science
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• v.7 no.3
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• pp.287-292
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• 2002

The effect of cooking methods on in vivo and in vivo indices of the protein quality of hagfish meat were investigated. In vivo protein digestibilities of cooked meats (81.3~83.5 %) were not significant different (p<0.05) from those of van meat (82.9%), with the exception of steamed (11$0^{\circ}C$, 15 min) meat (86.3 %). Convection oven cooking (22$0^{\circ}C$, IS min) resulted in a higher trypsin indigestible substrate (TIS, 49.2 mg/g solid) compared with that of raw meat (38.9 mg/g solid). free amino acid content of raw meat was decreased after boiling (10$0^{\circ}C$, 10min). Both convection oven and microwave cooking (2,450 MHz, 3 min) decreased available lysine from 4.9g/16g N to 3.8~4.1g/16g N. In vivo apparent protein digestibilites (AD) of hagfish meat were similar fur raw (92.4%) and cooked meats, but were somewhat lower than ANRC (Animal Nutrition Research Council) casein (945%). The PERs (3.7~4.1) and NPRs (3.7~4.9) of cooked meats were significantly higher (p<0.05) than those of raw meat (PER 3.3, NPR 3.6 and ANRC casein (PER 2.5, NPR 2.6), despite their lower in vivo protein digestibilities. These results demonstrate that cooking at optimal conditions resulted in remarkably positive effects on in vivo and in vivo protein qualities of hagfish meats. Therefore, steamed hagfish meat is an excellent source of high quality protein from seafood products.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.211-216
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• 1999

Protein nutritional quality of fish extracts processed at $110^{\circ}C$ for 5 hours with spicy vegetables (garlic, onion and ginger) were evaluated using in vitro and in vivo (rat assay) parameters, Protein and total lipid contents were closely related to the degree of discarding floated lipid on fish extracts and the kinds of added spicy vegetables. Hydrocooking ($110^{\circ}C$, 5 hours) tended to result in better protein qualities than high temperature cooking ($136\~140^{\circ}C$). Spicy vegetables had not remarkable effects on improving in vitro protein quality parameters. The fish extract with $10\%$ of ginger was generally higher in vitro protein digestibility than those of the other vegetables. In spite of generally higher in vivo protein digestibility of fish extracts containing spicy vegetables processed at mild condition ($110^{\circ}C$), Protein efficiency ratios (PER) of-these extracts were not higher than those of extracts processed at severe conditions ($136\~140^{\circ}C$).

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.10-15
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• 1996

To determine the quality of heated protein, in vitro method, invluding lysine, lysionalanine, and fructose-lysine as well as homoarginine by guanidination of lysine, was assessed using heated casein with of without glucose. In vivo methods such as PER, digestibility and BV were also tried on homoarginine, lysinoalanine, fructoselysine, and lysine. The nonreactive lysine for huanidination was hardly digestive, while the non heat damaged lysine side chanis in the protein were accessible for guanidination as well as for the digestion. A linear correlation(${\gamma}$=0.80) was obstained between PER and digestibility of the analysed lysine. Digestibility of homoarginine was higher that of true protein. However, in the guanidinated heated casein with glucose, digestibility of homoarginine was significantly reduced. It is suggested that the homoarginine method may mislead to over- or underestimation of the damaged protein quality.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1612-1612
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• 2001

The production of grain for export and domestic use is one of Australia's most important agricultural industries, and the NIR technique has been used extensively over many years for the routine monitoring of grain quality, particularly moisture and protein content. Because most Australian grain is intended for human food production, the determinants of grain quality for livestock feed, apart from protein, have been largely ignored. However the increasing use of grain for feeding to pigs, poultry, beef cattle and dairy cows has led to an important national research project entitled “Premium Grains for Livestock”. Two of the objectives of this project are to determine the compositional and functional characteristics of grains which influence their nutritional quality for the various classes of livestock, and to adopt rapid and objective analytical tests for these quality criteria. NIR has been used in this project firstly to identify a set of grain samples from a large population of breeders' lines which showed a wide spectral variation, and hence a potentially wide variation in nutritional value. The selected samples were not only subjected to an extensive array of chemical, physical and in vitro analyses, but also were grown out to produce sufficient quantities of grain to feed to animals in vivo studies. Additional grains were also strategically selected from farms in order to include the effect of weather damage, such as rain, drought and frost. In this study to date, NIR calibrations have been derived or attempted, on both ground and whole grains, for in vivo dry matter digestibility (DMD), pepsin-cellulase dry matter disappearance, protein, fat, acid detergent fibre, neutral detergent fibre, starch, in sacco DMD and in vitro assays to simulate starch digestion in the lumen and small intestine. Results so far indicate high calibration accuracy for chemical components (SECV 0.3 to 2.6%) and very promising statistics for in vivo DMD (SECV 1.8, $R^2$ 0.93, SD 7.0, range 61.9 to 92.3, n=60). There appears to be some potential for NIR to estimate some in vitro properties, depending upon the accuracy of reference methods and appropriate sample populations. Current work is in progress to extend the range of grains with in vivo DMD values (a very laborious and expensive process) and to increase the robustness of the various NIR calibrations, with the aim of implementing uniform testing procedures for nutritional value of grains throughout Australia.

• BMB Reports
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• v.38 no.3
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• pp.259-265
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• 2005

Proteins must fold into their correct three-dimensional conformation in order to attain their biological function. Conversely, protein aggregation and misfolding are primary contributors to many devastating human diseases, such as prion-mediated infections, Alzheimer's disease, type II diabetes and cystic fibrosis. While the native conformation of a polypeptide is encoded within its primary amino acid sequence and is sufficient for protein folding in vitro, the situation in vivo is more complex. Inside the cell, proteins are synthesized or folded continuously; a process that is greatly assisted by molecular chaperones. Molecular chaperones re a group of structurally diverse and mechanistically distinct proteins that either promote folding or prevent the aggregation of other proteins. With our increasing understanding of the proteome, it is becoming clear that the number of proteins that can be classified as molecular chaperones is increasing steadily. Many of these proteins have novel but essential cellular functions that differ from that of more 'conventional' chaperones, such as Hsp70 and the GroE system. This review focuses on the emerging role of molecular chaperones in protein quality control, i.e. the mechanism that rids the cell of misfolded or incompletely synthesized polypeptides that otherwise would interfere with normal cellular function.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.277-284
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• 1999

To confirm the food quality of conventionally processed fish extracts, protein quality of boiled crucian carp(Carassius carassius) and bastard halibut(Paralichthys olivaceus) extracts and their residues were evaluated. For the both fish extracts, some of the essential amino acids were lowered significantly but two times more proline and glycine were detected in extracts than those in raw fish meats. Boiling(100oC, 5 hours) caused 1.8(crucian carp)~2.4(bastard halibut) times more total free amino acid contents in fish extracts as compared to those in original fish meats. Taurine, glutamic acid, proline, lysine, and ammonia were the predominant free amino acids released in fish extracts. In vitro digestibility of boiled fish extracts were lower at a level of 4~6% than those of raw fish meats. Fish extraction residue had a higher in vitro digestibility and had a 60% lower level of TI than that of original fish meats. 18(bastard halibut)~ 24%(crucian carp) of available lysine was reduced in boiled fish extracts but a remarkable variation was not noted between extracts and residues. PERs and NPRs of fish extracts were significantly lower than those of casein, while those values of extraction residue were slightly higher as compared to those of control(ANRC casein). In vivo apparent digestibility exhibited a similar trend to in vitro digestibility. Hematological properties in serum of rat fed with fish extracts and residue were not changed significantly but the serum cholesterol concentration were reduced in rats fed fish extraction residue comparing with those of control. These results suggest that body weight loss due to fish extracts may not affect physiological changes.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.81-90
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• 2004

Farmers need timely information on the nutritional status of their animals and the nutritive value of pastures and supplementary feeds if they are to apply successfully this existing nutritional information. Near infrared reflectance(NIR) spectroscopy has been used over the last forty years to analyse accurately protein, fiber, and other organic components in animal foods. NIR spectroscopy is a rapid, non-destructive, and non-polluting technology. When properly calibrated, NIR spectroscopy is used successfully with both concentrate and forage feeds. NIR methods predict in vitro digestibility accurately and precisely, and can predict in vivo digestibility at least as well as conventional "wet chemistry" methods such as in vivo digestion or the pepsin-cellulase method, and much more rapidly. NIR technology has been applied to the routine monitoring (through analysis of feces samples) of the nutritional status of cattle and other grazing animals. This report reviews the use of near infrared reflectance(NIR) spectroscopy to monitor the nutritive value of animal feeds and the nutritional status of grazing animals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.263-270
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• 1982

In an attempt to evaluate the nutritional quality of seaweed protein, the effects of heat treatment on the in vitro digestibility and trypsin inhibitor content in seaweed were determined. In this study, the nitrogen-to-protein conversion factors were also calculated on the basis of quantitative amino acid data. The results are as follows : 1. The in vitro protein digestbilty of red seaweeds (P. teoera anc P. suborbiculata) were ranged from 78.5 to 82.2, and green seawerd (E. linza) and brown seaweeds showed value under 80 in vitro digestibility. In general, trypsin inhibitor contents in brown seaweed were higher (0.33-0.54 mg/g) than those of red seaweeds (0.26-0.39 mg/g). And it is noted that the lowest trypsin inhibitor content was shown in green seaweed (E. linza) in spite of lowest in spite digestibility (78.5). 2. The in vitro protein digestibility of sun dried laver (P. tenera) was increased with cooling time (microwave heating), but it was not significant. Hot plate cooking raised the in vitro digestibility from 81. 1 to 84.5. The influence pot cooking time on trypsin inhibitor content was inversely proportional to in vitro digestibility. 3. Computed nitrogen factor, based on amino acid content (Factor method) and Kjeldahl nitrogen content (Kjeldahl mettled), were 5.83 (H. fusiforme)- 6.52 (P. tencra) as Factor method and 5.40 (U. pinnatifida)-6.29 (P. tenera) as Kjeldahl method. Individual value for each nitrogen conversion factor differed by species, especially in brown seaweeds. The best estimate of the protein content of seaweed can be calculated, from multiplying the summed amino acid content by conversion factor (Factor method).