• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.426-430
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• 1985

The effects of temperature on the visual color deterioration of Lithospermi radix were investigated under steady conditions of various pH and temperature. The changes of Hunter L, a, b, and ${\Delta}E$ values related to the color deterioration were sharply increased above $50^{\circ}C$ and the deteriorations were expressed linear relationships with the temperature above $60^{\circ}C$. Linear regression coefficients of Hunter L, a, b values decreased with an increase of heat treatment time, whereas the color difference was increased. The linear regression coefficients of Hunter L, a, b, ${\Delta}E$ values in 66.7% ethanol extract solution of Lithospermi radix for 1 hr were -0.3696, -0.4124, -0.2279, and 0.5983, respectively. Inear regression coefficients in color difference (${\Delta}E$) could be calculated from the coefficients in Hunter L, a, b values. The low pH treatment of extract from pH 6.07 to pH 1.35 led to decrease of Hunter a value and a little increase of Hunter L, b values, but the high pH treatment above pH 6.07 decreased all Hunter values. Particularly, the visual color of the extract of Lithospermiradix was appeared to be faborable at pH 4.0-6.5, which was a bright red color.

• Food Science of Animal Resources
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• v.21 no.4
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• pp.323-328
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• 2001

Meat quality of the domestic pork carcasses(n=330) classified in 3 groups according to the Hunter L values postmortem($\leq$50, 50.1∼55.0 and $\geq$55.1) was investigated. The carcass temperature(3, 5, 10 and 15hr postmortem) and temperature falling rate of postmortem increased as the Hunter L value increased. The pH postmortem(pH$\_$ohr/, pH$\_$24hr/) decreased as the Hunter L value decreased. In physical traits, the water holding capacity(WHC) increased and the purge loss decreased as the Hunter L value increased. However, shear force, cooking loss and fat hardness were not significantly different among different. Hunter L value groups(p<0.05). The meat color indices(CIE L*, a*, b*, chroma, hue and ΔE) increased as Hunter L value increased. The sensory characteristics had no significant difference among different Hunter L value groups(p<0.05). In conclusion, the results suggested that Hunter L values were related with pork quality such as temperature, pH, physical traits and color.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.165-167
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• 1983

Oxy - and metmyoglobin concentrations in beef chuck were measured by Hunter-Lab and spectrophotometer. The values of oxymyoglobin by Hunter-Lab got 34.03, 10.40, and 6.50 as average in L, a, and b while the CIE color primaries were 13.33, 11.58, and 9.94 in X, Y, and Z, respectively. The metmyoglobin values recorded 39.10, 13.20, and 10.13 in L, a, and b, of which values were converted to 17.88, 15.29, and 11.40 in X, Y, and Z of the CIE primaries. Absorption spectrum of oxymyoglobin showed 2 peaks which were 0.79 and 0.83 pf extinction coefficient with 530 and 570nm in wavelengh, and that of metmyoglobin appeared on an irregular curve with a summit of 0.58 and 500 in extinction coeffcient ($cm^2$/mg) and wavelength(nm) each.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.47-52
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• 1999

Comparative effects of phosphine fumigation and gamma irradiation were evaluated on the qualities of white ginseng prepacked in a commercial laminated film in terms of water absorption, Hunter color parameters(L, a, b) and organoleptic properties(overall color/appearance, flavor) during 6 months of storage at ambient(20oC, 70% RH) and accelerated(40oC, 90% RH) conditions. Moisture content of packed white ginseng(initial 8.44%) linearly increased with storage period, thereby reaching to about 10% (r=0.9966) in ambient and more than 15%(r=0.9886) in accelerated conditions, respectively, at the 6th month of storage. The storage at severe conditions resulted in remarkable changes in Hunter's color values, decrease in whiteness(L) and increase in redness(a) and yellowness(b), while both treatments, phosphine and irradiation less than 5kGy, did not cause any significant changes in color parameters. Phosphine fumigation was shown detrimental to overall flavor of white ginseng(p<0.01), however or ganoleptic qualities of stored samples were effectively maintained by irradiation less than 5kGy(p< 0.05). As the index on the guality of white ginseng stored at severe conditions its organoleptic quality was highly correlated with moisture content(r= 0.9777) and Hunter color values(over 0.9), suggesting the critical values of 15.5% moisture and 72.56, 7.15, 21.45 in Hunter's L, a, b values, respectively.

• Food Quality and Culture
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• v.3 no.2
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• pp.89-93
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• 2009

This study was conducted to investigate the effects of herbs (dill weed, fennel seed and rosemary) on color stability and lipid oxidation of ground pork patties during storage at $2^{\circ}C$ and $-20^{\circ}C$. Lipid oxidation was determined by the thiobarbituric acid reactive substances (TBARS) method. Fennel seed was identified as being the most effective ingredient in terms of meat redness (Hunter a-values) during storage at $2^{\circ}C$ (p<0.05). Patties treated with rosemary had lower Hunter a-values than control, and dill weed was the least beneficial in influencing meat redness, having significantly lower a-values than control patties. During frozen storage at $-20^{\circ}C$, no significant differences in a-values were observed between the control patties and those treated with fennel seed. Patties treated with rosemary had lower a-values than control and patties with dill weed had negative a-values throughout storage. The cooking process increased Hunter L-values and decreased a-values in all patty samples. TBARS values increased during storage. Rosemary displayed excellent antioxidative activity as evidenced by the completely inhibition of TBARS formation of cooked pork patties. Dill weed and fennel seed also exerted an intermediate but significant antioxidant effect during storage (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.3
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• pp.466-470
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• 2001

Response surface methodology was used for monitoring extraction conditions, based on quality properties of old pumpkin extracts. Hunter's color L value of extracts was maximized at 101℃, 2.6 hr and decreased gradually after maximum point. The polynomial equation for Hunter's color L value showed 10% of significance level and 0.8799 of R². Hunter's color a value was minimized at 117℃, 3.9 hr and R² of polynomial equation was 0.9852 within 1% significance level. Hunter's color b value and ΔE value increased as the extracting temperature and time increased. Extraction yield of old pumpkin was maximized at 110℃, 4 hr and increased in proportional to the extracting temperature and time, but decreased after 113℃ and 2 hr. Viscosity of pumpkin extracts were maximized at 120℃, nearly 3 hr. R² of polynomial equations for yield, viscosity and sugar content were 0.9532, 0.9812 and 0.8869, respectively. Optimum ranges of extraction conditions for quality properties of old pumpkin were 102∼109℃, 2.5∼3.5 hr, respectively. Predicted values at the optimum extraction condition agreed with experimental values.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.410-413
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• 1991

Prefried chicken patties were irradiated at dose levels of 0, 2, and 4 kGy using $Co^{60}$ source and stored at $3{\pm}1^{\circ}C$ and $-10{\pm}1^{\circ}C$, separately for the evaluation of color and sensory characteristics. Irradiation dose of 4 kGy slightly darkened the internal color of chicken patties. Except for the internal portion of the frozen samples, an increase (p<0.05) in Hunter 'L' values was observed for both the surface and interior of patties during storage. Upon refrigerated storage, Hunter 'a' values, both on the surface and internally, decreased as the storage period progressed. Only storage period affected (p<0.05) the Hunter 'b' values of patty surfaces and interiors. No difference (p<0.05) in odor, taste, color, and texture of the patties was observed for irradiation dose and storage period as evaluated by triangle tests except between 2 kGy and 4 kGy irradiated samples before forzen storage.

• Food Science of Animal Resources
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• v.21 no.3
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• pp.200-207
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• 2001

Effects of dietary chitosan on physico-chemical properties of pork were investigated. A total 24 pigs (55$\pm$5kg) were fed a control diet (a commercial feed) or chitosan-supplemented diets (T1: 0.2% chitosan, T2: 0.4% chitosan, T3: 0.6% chitosan) for 6 weeks. The 6 weeks later the initiated of the experiments, pigs were slaughtered and loins were collected from each treatment groups. The samples were stored at 0$\pm$1$^{\circ}C$ for 15 days. Ultimate pH tended to higher in the control than those in the treatments, and that of T3 was significantly lower than those of the others (P<0.05). Shear force and the total moisture contents were not significantly different between control and treatments and they decreased with storage days (P<0.05). Hunter L* values of control, T1 and T2 were significantly lower than that of T3 at 1 and 10 days (P<0.05). Hunter a* values of control were significantly higher than that of others at 1 and 5 days (P<0.05). Hunter b* values of control were significantly higher than that of others at 5 days (P<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.831-837
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• 1997

Response surface methodology(RSM) was applied in roasting processes of Polygonatum odoratum roots in order to monitor Hunter color parameters and to optimize organoleptic properties of the tea. In roasting processing based on the central composite design with variations in roasting temperature (110~19$0^{\circ}C$) and roasting time(15~75min), coefficients of determinations($R^{2}$) of the models were above 0.9827(p<0.01) in Hunter color parameters and above 0.7748 in organoleptic properties. Hunter color L and $\Delta$E values of the powdered samples decreased with the roasting processes, whereas Hunter color a and b values increased up to around 59 min at 136$^{\circ}C$ and thereafter showed a decreased tendency. Organoleptic qualities on color, taste and aroma of Polygonatum odoratum tea were improved along with roasting processes, thereby estimating the optimum roasting conditions by RSM for the maximized qualities of organoleptic properties as a range from 127$^{\circ}C$ to 135$^{\circ}C$ and from 60min to 66 min. Hunter color a value(redness) was found to generate a similar response surface to that of organoleptic properties, showing the possibility of quality index in roasting processes of Polygonatum odoratum roots.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.219-225
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• 2000

Physicochemical changes of refrigerated chicken legs treated with acetic acid and trisodium phosphate (TSP) during storage at the temperature of 1$\pm$2。C or 4。C. Chicken (average weight of 500$\pm$30 g) legs were treated with 2.5-10% (w/v) TSP and 0.5-2%(v/v) acetic acid soluions at exposure times of 10 min. pH values of chicken legs treated with 2.5-10% TSP significantly (P<0.05) increased at initial days compared to control, which were consistent with the results of treatments of 5-10% TSP solutions fur storage of 8 days at retail levels. Thiobarbituric acid (TBA) values of chicken legs treated with 2.5-10% TSP or 0.5-2% acetic acid solutions significantly increased from initial days to 4days of storage compared to controls. pH values of chicken legs treated with 0.5-2% acetic acid significantly decreased at initial days compared to control, which were consistent with the results of treatments of 1.5-2% acetic acid solutions for storage of 16 days at 4。C. Chicken legs treated with 0.5-2% acetic acid solutions were a significantly different Hunter color L$^+$ values during storage of 4 and 8 days compared to the controls. Chicken legs treated with 1-2% acetic acid solutions were a significantly different Hunter color a$^+$ values during storage of 16 days compared to the controls. Chicken legs treated with 0.5-2% acetic acid solutions were a significantly different Hunter color b$^+$ values during storage from 4 to 12 days compared to the controls.