• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.427-436
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• 2001

The effects of storage form (paddy and milled rice) and storage period (1, 2, and 3 years) of rice at low temperature $(4^{\circ}C)$ on physicochemical properties of milled and cooked rice and sensory characteristics of cooked rice were investigated. The proximate compositions except moisture content of rice decreased as the storage period increased. Water binding capacity, solubility and swelling power of rice flour decreased with the extended storage period. In the amylogram, the initial pasting temperature, paste viscosity and breakdown of paddy rice flour slurry decreased after 2 years of storage. Moisture content of cooked rice increased while the amount of water evaporated during cooking decreased. These trends were obvious with the longer storage period. Lightness and yellowness of cooked rice were greatly changed after 3 years of storage, regardless of storage form. Texture profile analysis of cooked rice by Texture Analyzer revealed that hardness, fracturability, gumminess were gradually increased while adhesiveness decreased as the storage period of rice increased. A trained panel found that color intensity, intactness of grains, rancid flavor, rice bran flavor, wet cardboard flavor, hardness and chewiness of cooked rice increased with the longer storage period. However, glossiness, transparency, plumpness, puffed corn flavor, dairy flavor, boiled egg white flavor, sweet taste, adhesiveness to lips, smoothness and inner moisture decreased with the extended storage period up to 3 years. Instrumental hardness was highly correlated with sensory hardness.

• Journal of Mushroom
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• v.12 no.4
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• pp.287-292
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• 2014

This study investigated the packaging status and sensory quality of fresh-cut mushroom products from retail markets. Fifty one fresh-cut mushroom products were surveyed / purchased from discount stores in four cities in January (winter), March (spring), August (summer), and October (autumn) 2009. Collected fresh-cut mushrooms include single variety products like whole oyster mushroom and winter mushroom, diced or sliced oak mushroom, sliced king oyster mushroom, and ready-to-cook mixed mushroom products. Most fresh-cut mushrooms were packed in trays made of aluminum, polystyrene (PS), polyethylene terephthalate (PET), nylon materials covered with PVC (polyvinyl chloride) wrap or solid PP (polypropylene) and PS. Eighty nine percent of the covers were labeled with manufacture and expiration date. Collected samples showed severe browning (10%) and off-flavor (4%). The percentage of products with a rating of 'good' or better in overall quality was 90%. Moreover, Survey showed seasonal differences in sensory qualities. All of the collected fresh-cut mushrooms in autumn and winter had high marketability. However, Mushroom products collected in spring and summer had lower quality, hence requires treatment to prevent browning and off-flavor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1307-1313
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• 2011

This study was conducted to evaluate the effects of irradiation temperature on the physicochemical and sensory properties of Tarakjuk, milk porridge. Tarakjuk was gamma-irradiated at different temperatures of $25^{\circ}C$ (in room), $4^{\circ}C$ (in ice), and $-20^{\circ}C$ (in dry ice) at a dose of 10 kGy, and then autoclaved at $120^{\circ}C$ for 15 min for comparison. pH and Hunter's color value of Tarakjuk were not changed by irradiation regardless of the temperature. However, the TBA (2-thiobarbituric acid) value decreased as irradiation temperature was decreased. The viscosity of Tarakjuk irradiated in dry ice was significantly higher than that irradiated at room temperature and in ice (p<0.05). For the sensory evaluation, there were no significant differences in overall acceptability between non-treated Tarakjuk and that irradiated in dry ice. Flavor pattern analysis using an electronic nose with a SAW (surface acoustic wave) sensor determined that the main peaks at retention times 3.88 and 7.34 sec were related with off-flavor induced by irradiation and unique flavor of Tarakjuk, respectively. These results indicated that irradiation at freezing temperature improved quality deterioration of Tarakjuk by gamma irradiation. However, sensory quality of Tarakjuk irradiated at freezing temperature was still lower than that of non-irradiated Tarakjuk. Therefore, further research is needed to improve the quality of Tarakjuk using combined treatment such as addition of antioxidants and vacuum packaging method.

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.218-225
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• 2010

To make sponge cake using Lentinus edodes powder, which is useful and valuable as a functional food material, we tested samples with 3, 6, 9, and 12% L. edodes powder to ascert200ain the quality characteristic and make optimize preparation. Samples and L. edodes powder-free control sponge cakes were compared in terms of quality characteristics including batter viscosity and specific gravity, moisture content, volume index, weight, color, textural characteristics, and sensory qualities, to determine the optimal ratio of L. edodes powder in the formulation. Viscosity and specific gravity of sample and control batter were not significantly different. Moisture content of the sample and control sponge cake also did not differ significantly, and weight of sample and control sponge cakes did not differ appreciably. The volume index of the samples displayed contrasting values, increasing with 3~6% L. edodes powder and decreasing with 9~12% powder. L, a, and b crust color values of samples sponge cakes were lower than those of control cakes. The L and a values of the control cakes was maximal, with values progressively decreasing with incorporation of more L. edodes powder. The b value decreased by 3% with the addition of up 6% L. edodes powder with no further decrease thereafter. L. edodes powder was the lower value. So was the color a, and L. edodes powder increased, a-values decreased. 3% difference was shown in b, the color and none between the samples with 6~12%. L. edodes powder showed lower values making a comparison with the control. Hardness and fracturablility were not appreciably affected by 3% L. edodes powder, but was affected by concentrations 6%. Fracturability og sample sponge cakes was consistently lower than control cakes. Fracturability made little difference in 3% samples, but it was not the same with more than 6% L. edodes powder samples; the samples showed lower value than the control. Adhesiveness was not significantly affected. Chewiness was lower in all sample cakes except those prepared with 3% L. edodes powder. Use of L. edodes powder conferreds higher resilience values as compared to thecontrols. Sensory attributes of color, flavor, softness and overall acceptability were the highest in control sponge cakes, as the amount of L. edodes powder increased, the acceptability decreased. L. edodes-flavor, pleasant taste and off-flavor were the lowest in control cakes, and values increased as the amount of L. edodes powder increased. The control sponge cakes showed the highest values in egg-flavor and moistness, which progressively increased as added L. edodes powder increased. The results indicate that control sponge cakes displayed were. the highest overall acceptability, with acceptability decreasing and it decreased as L. edodes powder content increased. However, 3~6% L. edodes powder can produce an acceptable product, and may be used as anoptimized mixture ratio.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1786-1793
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• 2005

The study compared the fatty acid profiles of 3 muscles (Longissimus dorsi, LD, Triceps brachii, TB and Semimembranosus, SM) obtained from Korean Hanwoo (18 steers, 24 months old) and Australian Angus beef (18 steers, 24 months old) and assessed their role in sensory perception. The samples of each carcass were prepared in the same manner, and cooked both as traditional grilled steaks and Korean BBQ style. A total of 720 Korean sensory panelists evaluated the beef samples for tenderness, juiciness, flavor, and overall liking. Oleic acid (18:1) was significantly (p<0.05) higher in TB than that in LD and SM. The essential linoleic acid (C18:2) was significantly (p<0.05) higher in TB and SM than that in LD. For LD muscle, the proportion of saturated fatty acids was significantly (p<0.05) highest, while that of polyunsaturated fatty acids was lowest among the three muscles. Australian Angus beef had significantly (p<0.05) higher n-3 PUFA than that of the Korean Hanwoo for the three muscles, while the latter contained significantly (p<0.05) higher n-6 PUFA than that of the former. The clustering analysis showed that there a was significant difference in fatty acids such as C16:0, C16:1n7, C18:0, C18:2n6, C18:3n3, C20:3n6, C20:4n6, C22:4n6, and C22:5n3 for sensory perception (tenderness, juiciness, flavor and overall likeness) of the beef from two origins (p<0.05) among three clusters. Especially, C14:0 had a significant effect on sensory perception only for Korean Hanwoo beef; while C20:5n3 had a significant (p<0.05) effect only for Australian Angus beef based on clustering with the sensory variables.

• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.709-712
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• 1994

The volatile components of citron juice juice extracted by three methods, which were Rotary-crushing and screening method (method I), Pressing method (method II) and Belt pressing method (method III), were analyzed with GC and GC/MS. Juice extracted by method III had more components of flavor than those by methods I and II. Also, the contents of total volatile components in method III were about 1.36 and 1.59 times than those in methods I and II, respectively. Limonene in juice extracted by method III was predominantly occupied, amount of which was 76.87%. Other important components were terpene hydrocarbons, such as ${\gamma}-terpinene$, ${\alpha}-terpinene$ and so on.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.10
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• pp.1373-1380
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• 2014

The thyroid hormone responsive protein (THRSP) gene is a functional gene that can be used to indicate the fatty acid compositions. This study investigates the relationships of exonic single nucleotide polymorphisms (SNPs) in the THRSP gene and fatty acid composition of muscle fat and marbling score in the 612 Korean cattle. The relationships between fatty acid composition and eight SNPs in the THRSP gene (g.78 G>A, g.173 C>T, g.184 C>T, g.190 C>A, g.194 C>T, g.277 C>G, g.283 T>G and g.290 T>G) were investigated, and according to the results, two SNPs (g.78 G>A and g.184 C>T) in exon 1 were associated with fatty acid composition. The GG and CC genotypes of g.78 G>A and g.184 C>T had higher unsaturated fatty acid (UFA) and monounsaturated fatty acid (MUFA) content (p<0.05). In addition, the $ht1^*ht1$ group (Val/Ala haplotype) in a linkage disequilibrium increased MUFAs and marbling scores for carcass traits (p<0.05). As a result, g.78 G>A and g.184 C>T had significantly relationships with UFAs and MUFAs. Two SNPs in the THRSP gene affected fatty acid composition, suggesting that GG and CC genotypes and the $ht1^*ht1$ group (Val/Ala haplotype) can be markers to genetically improve the quality and flavor of beef.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.33-37
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• 2003

Sensory quality of pine nut gruel was investigated to determine the effects of processing conditions on its quality. Response surface methodology was applied to investigate effects of water volume and pine nut weight ratios to rice weight and heating time on the preference of pine nut gruel in terms of color, flavor, viscosity, taste, and overall acceptance. Results showed that processing conditions did not affect the color of pine nut gruel. Viscosity and overall acceptance were affected by the ratio of water volume to rice weight and heating time. $R^2$ of response surface regression equations were 0.6954, 0.8333 (p<0.05), 0.9668 (p<0.01), 0.8664 (p<0.05), and 0.8159 (p<0.10) for color, flavor, viscosity, taste, and overall acceptance respectively. No relationship was observed between color and overall acceptance. The relationship between viscosity and overall acceptance was the highest.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.565-569
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• 2003

The objective of this experiment was to determine the effects of different levels of refined cod liver oil (RCLO) on laying performance, n-3 polyunsaturated fatty acids composition (n-3 PUFAs) and the organoleptic evaluation of duck egg yolks. A total of 180 30 wk old laying Tsaiya ducks, at the beginning of peak production, were allotted into 6 treatments with 3 replicates each. Ducks were fed one of the 6 experimental diets, supplemented with 2% tallow (control) and graded levels of RCLO at 2, 3, 4, 5, and 6% to a corn-soybean diets, respectively, for 6 wks. All of the experimental diets were formulated to be both isocaloric and isonitrogenous. Feed and water were supplied ad libitum throughout the experimental period. The results indicated that the RCLO supplementation levels did not affect (p>0.05) egg production, egg mass, feed intake, feed efficiency or body weight change. Egg weight was the lightest when the ducks received the 6% RCLO diet. The eicosapentaenoic acid, docosahexaenoic acid, and total n-3 PUFAs contents in the yolks increased with increasing RCLO supplementation. The taste and general acceptability of the hard-boiled eggs were not significantly different among the treatments. However, a fishy flavor was much higher when ducks were fed diets supplemented with 5% and 6% RCLO diets.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.584-591
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• 2019

Of all the various types of tea that are available, Pu-erh tea has attracted much attention because of its healthpromoting effects. The objective of this study was to investigate the physicochemical and antioxidant properties of two types of Pu-erh tea, Gushu Pu-erh and typical Pu-erh, extracted at 80 and 100℃, respectively. The Gushu Pu-erh extracts showed lower pH but higher antioxidant potential at both the temperatures, as compared to the typical Pu-erh. The mineral content of the tea extracts was greater at 100℃ than at 80℃. Among the seven categories of the flavor compounds that were detected, the peak area of esters was the highest in the Gushu Pu-erh extracts. The type of tea and the extraction temperature significantly affected the physicochemical and functional properties of these tea extracts. This study revealed that Gushu Pu-erh extracted at 100℃ for 3 min with 30 s of shaking provides better results in terms of the antioxidant potential and mineral content.