• Journal of the Korean Home Economics Association
• /
• v.29 no.4
• /
• pp.25-35
• /
• 1991

This study was carried out to determine the proximate composition, amino acids and fatty acids contents and changes of physicochemical characteristics of each oil extracted from Spanish and Virginia type peanuts grown in Korea roasted at 110, 120, 130 and 14$0^{\circ}C$ for 2 minutes. 1. The moisture contents of raw Spanish and Virginia type peanuts were 6.5~6.8% respectively. The crude ash and reduced sugar contents of raw Spanish and Virginia type peanuts were 2.3% and 16.5% and the crude protein content was 27.0% in Spanish type peanuts and was aproximately 1% higher than in Virginia type peanut. The protein content was 25.7%~26.7% in Virginia type peanut roasted at 110, 120, 130 and 14$0^{\circ}C$. The crude fat content of Virginia type peanut was 46.0% which was aproximately 1% higher than that of Spanish type. But four kinds of oils content were 51.3%~51.8% in Spanish type peanut roasted at 110, 120, 130 and 14$0^{\circ}C$, which was about 2% higher than those of Virginia type. 2. Amino acids existed in peanut were glutamie acid, arginine, aspartic acid, leucine, glycine, phenylalanine, proline-lysine, tyrosine, valine and isoleucine, etc mainly. But methionine and threonine contents were very low. The content of glutamic acid was the highest in 71.6-81.7mg among amino acids. Glutamic acid content of Virginia type peanut was about 12% higher than that of Spanish type peanut. Total amino acid content was 441.8mg/g in Virginia type peanut and that was 16% higher than that of Spanish type peanut. The lysine content of Spanish and Virginia type peanuts roasted at 14$0^{\circ}C$ were 24% and 13%, these were lower than those of peanuts roasted at 11$0^{\circ}C$. 3. Main fatty acids of raw Spanish and Virginia type peanut oils were oleic(40.99-46.58%), linoleic(33.21-38.82%) and palmitic acid(9.72-11.58). Linoleic acid content of raw Virginia type peanuts was 5.6% higher than that of raw Spanish type peanut. And the oleic acid content of Spanish and Virginia type peanuts roasted at 11$0^{\circ}C$, 12$0^{\circ}C$, 13$0^{\circ}C$ and 14$0^{\circ}C$ was 50-53% and 41-43% respectively. Linoleic acid content of Spanish and Virginia type peanuts roasted at same temperatures as the former was about 28-31% and 37-38% respectively. That linoleic acid content of roasted peanuts was lower than that of raw peanuts. Linoleic acid content of raw and roasted Virginia type peanut, were higher than that of Spanish type peanuts. 4. Acid value and peroxide value of oils extracted from roasted Spanish and Virginia type peanuts were much higher than those of oils extracted from raw peanuts. The maximum AVs of oils extracted from Spanish and Virginia type roasted peanuts were samples roasted at 12$0^{\circ}C$and those AVs were 0.50 and 0.63 respectively. And the maximum POVs of oils extracted from Spanish and Virginia type roasted peanuts were samples roasted at 12$0^{\circ}C$ also and those POVs were 26.8 and 32.8 meq/kg. oil respectively. Acid value and peroxide value of oils extracted from roasted peanuts were increased with increasing the roasting temperatures from 11$0^{\circ}C$ to 12$0^{\circ}C$, then decreased, while TBA values were increased continuously with increasing the roasting temperatures.

• Journal of agriculture & life science
• /
• v.45 no.4
• /
• pp.121-133
• /
• 2011

Effects of roasting on vitamin E content, color, microstructure and moisture of peanuts, and vitamin E content in peanut oils prepared from the roasted peanuts were investigated. Runner-type peanuts were roasted at 140, 150, and $160^{\circ}C$ for 10-20 min. As roasting temperature and time increased, the CIELAB $L^*$ value of peanuts decreased while $a^*$ and $b^*$ values increased, resulting in formation of the golden brown color of roasted peanuts. Moisture ratio (M/Mo) and color $b^*$ value of peanuts roasted at 140 to $160^{\circ}C$ showed a correlation of $b^*=21.61\;(M/Mo)^2-40.62\;(M/Mo)+34.12$ ($R^2=0.9123$). Overall changes in the tocopherol contents of peanuts and peanut oils were significantly affected by roasting temperature and time (p<0.05). Roasting at $140^{\circ}C$ caused a slight increase in the levels of tocopherols of peanuts over roasting time up to 20 min (p<0.05). There was no significant change in the tocopherol levels of peanuts during roasting at $150^{\circ}C$ for 20 min (p>0.05). At $160^{\circ}C$, the levels of tocopherols significantly decreased during the initial 10 min of roasting (p<0.05) while there was no extended loss after 10 min, resulting in about 5, 12, 20, and 10% losses of ${\alpha}$-, ${\beta}$-, ${\gamma}$- and ${\delta}$-T, respectively. After 20 min, total tocopherols decreased by 18%. However, tocopherol contents of pressed peanut oils significantly decreased at all roasting temperatures (p<0.05). After roasting peanuts at $160^{\circ}C$ for 20 min, about 84% of initial ${\alpha}$-T in peanut oils was retained. ${\alpha}$-T was the most stable to roasting while ${\gamma}$-T was the least. Swollen epidermal cells on the inner surface and broken cell walls of parenchyma tissue of peanut cotyledon were observed in peanuts after roasting at $160^{\circ}C$ for 15 min. Severe changes in microstructure of peanut by roasting would contribute to vitamin E stability because of exposure of oil droplets in peanuts to oxygen.

• Journal of the Korean Society of Food Culture
• /
• v.32 no.2
• /
• pp.128-134
• /
• 2017

The purpose of this study was to investigate the quality characteristics of roasted peanuts and the antioxidative effect of peanut oil added with sesame oil. Saltiness of roasted peanut increased with increasing salt content. In terms of color value, L and b values decreased as increasing concentration increased, whereas a value increased with increasing salt content. Overall, sensory evaluations proved that roasted peanuts with 15% added salt was preferred over other samples. For peanut oil added with sesame oil, acid values increased during the storage period, whereas samples made with sesame oil had lower values than the control group. Peroxide values increased rapidly for 21 days and then decreased. The acid and peroxide values were lower in peanut oil added with 50% sesame oil compared to peanut oil added with 30%, 10%, and 70% sesame oil, as well as the control. The TBA values of peanut oil made with 50% and 30% sesame oil were lower than those of the control and 70% and 10% sesame oil. According to the Rancimat method, PS-50% (524 min) and PS-30% (453 min) demonstrated longer induction periods as compared to the control (280 min), PS-70% (445 min), and PS-10% (291 min) samples.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.18 no.2
• /
• pp.216-222
• /
• 1989

Water adsorption characteristics and lipid rancidity of fresh and roasted Peanuts were investigated at $25{\sim}60^{\circ)C$ and $11{\sim}85%$ relative humidity. peanuts of 50g were reached to the equilibrium water content in 14 days at $40^{\circ}C$, in 30 days at $25^{\circ}C$, respectively, in all of the relative humidity. BET monolayer water contents were $2.19{\sim}2.69%$ in fresh peanuts and $2.47{\sim}2.67%$ in roasted ones as dry basis at $25{\sim}40^{\circ)C$. Zero order reaction rate of peroxide value(POV) were $8{\sim}21times$ lower as $0.032day^{-1}$ and $0.142day^{-1}$in fresh peanuts than those of $0.663day^{-1}$ and $1.120day^{-1}$ in roasted peanuts at water activity of 0.51, but those were showed the relatively smaller differences according to the water activity and temperature. The critical peroxide value(POV) and carbonyl value(CV) were determined as 15.0meq/kg and 4.7meq/kg at $60^{\circ}C$ $0.51a_w$ by the regression analysis between chemical and sensory evaluation.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.6
• /
• pp.1212-1219
• /
• 1999

The oils were extracted from the mixture of roasted(for 20 min at 190oC) perilla seeds(RPS) and roasted (commercially) peanuts(RPN) by solvent extraction(SE) and mechanical expression(ME). The effects of mixing ratio on physicochemical characteristics and oxidative stability of their oils were investigated. Yields of both SE and ME oils were increased as the RPN ratio in the mixture increased. In all the SE and ME oils, the major fatty acids were oleic, linoleic and linolenic acid, and total saturated fatty acids increased gradually, but total unsaturated fatty acids decreased gradually as the RPN ratio in the mixture was increased. The specific gravity and refractive index of both SE and ME oils decreased as the RPN ratio in the mixture was increased. Acid value, saponification value and iodine value of SE oils decreased as the RPN ratio in the mixture increased, whereas acid value and iodine value of ME oils decreased and saponification value increased. The colors of ME oils were darker brownish than SE oils. The oxidative stability of SE oils was decreased as the RPN ratio in the mixture increased, whereas that of ME oils was increased. Sensory evaluation of all the oils extracted from the mixture with various mixing ratio showed significant differences in flavor, taste, color and overall acceptance(p<0.01). The oil extracted from the mixture of the mixing ratio of 8:2(RPS:RPN) showed slightly higher preference regardless of extraction method.

• Korean Journal of Plant Resources
• /
• v.20 no.6
• /
• pp.553-557
• /
• 2007

The purpose of this study is to establish an extraction and analysis method for $\alpha$-tocopherol, and to then distinguish among varieties. The $\alpha$-tocopherol contents of 22 varieties of peanut seeds were analyzed by HPLC. Peanut seeds of cv. Palkwang were processed in two ways, by boiling and roasting. The $\alpha$-tocopherol contents of the two types of peanuts were compared with fresh seeds without any processing. $\alpha$-Tocopherol was detected at a retention time of 2.95 minutes. Five standards of $\alpha$-tocopherol covering a range of $20{\sim}100{\mu}g/ml$ were made up in 2% isopropyl alcohol/n-hexane and analyzed in duplicate. The $\alpha$-tocopherol contents differed according to extraction temperature. The contents were $85{\mu}g/g$ or less at $10^{\circ}C\;and\;20^{\circ}C$ and $94{\mu}g/g$ at $30^{\circ}C$, but they were decreased at $40^{\circ}C$ or higher. The $\alpha$-tocopherol contents in 22 peanut varieties were $61.36{\sim}96.80{\mu}g/g$ according to variety. Fresh peanuts contained $106.7{\mu}g/g$ of $\alpha$-tocopherol, while boiled peanuts contained $108.8{\mu}g/g$ of $\alpha$-tocopherol, and roasted peanuts contained $109.2{\mu}g/g$ of $\alpha$-tocopherol.

• Korean Journal of Plant Resources
• /
• v.20 no.6
• /
• pp.558-562
• /
• 2007

The high-performance liquid chromatography(HPLC) method for the determination of trans-resveratrol in 34 germplasms and processing methods of peanut seeds has been modified. Peanut germplasms contained trans-resveratrol contents of $0.14{\sim}4.96{\mu}g/g$, but findings for the testa color were not significant. However, two germplasms, 'KIGAN' and 'CS1', contained more trans-resveratrol contents than the other germplasms. The contents of their were $2.26{\mu}g/g\;and\;4.96{\mu}g/g$. The tested processing methods caused no significant changes in trans-resveratrol contents. The contents of fresh, boiled, and roasted peanuts were 0.36, 0.32, and $0.40{\mu}g/g$, respectively in cv. Palkwang, and 0.22, 0.22, and $0.26{\mu}g/g$, respectively, in cv. Jakwang. Differences were not significant among fresh, boiled, and roasted peanuts. The grains of 'Palkwang' and 'Jakwang' contained trans-resveratrol contents of $0.34{\mu}g/g\;and\;0.24{\mu}g/g$, and testa contained $1.12{\mu}g/g\;and\;1.00{\mu}g/g$, respectively. However, when comparing absolute quantity, the trans-resveratrol contents appears to be approximately $3{\sim}4$ times higher in the testa than in the grain of the peanut, although the total contents were not different because the ratio of testa was low in peanut seeds.

• The Korean Journal of Food And Nutrition
• /
• v.32 no.2
• /
• pp.155-159
• /
• 2019

The purpose of this study was to evaluate the antioxidant activity of roasted and germinated peanut flours. This study also aims to utilize it as a functional material to be applied to processed foods. The moisture, crude protein, crude fat and ash carbohydrate contents of the common peanut powder used in this study were 1.27, 25.63, 42.19, 2.38, 28.20 g / 100 g, respectively. The moisture content, crude protein, crude fat and ash carbohydrate in germinated peanut powder were 1.47, 25.86, 42.86, 2.25 and 26.66 g / 100 g, respectively. 26.52, 45.02, 2.33, 24.70, g / 100 g, and the dietary fiber content of peanut, roasted peanut and germinated peanut powder was 12.27, 13.05 and 14.22 g / 100g, respectively. The antioxidants and radical scavenging ability of polyphenols and flavonoids in peanut powder treated with germination and germination compared to ordinary peanuts. Resverasterol content was high in the germinated peanut powder. Especially, germinated peanut powder can act as a natural antioxidant.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.46 no.4
• /
• pp.279-283
• /
• 2001

The content and composition of tocopherol were analyzed in peanuts produced in Korea. The tocopherol assay was consisted of an extraction with n-hex-ane:isopropanol mixture followed by high pressure liquid chromatography with fluorescence detection. Tocopherol content was higher in leaves and seeds but lower in seed coats and shells. $\alpha$-/${\gamma}$- Tocopherol ratio was as low as 0.53 in seeds and as high as 22.5 in shells. Tocopherol content in seeds of nine varieties ranged from 142 to 220 ng/mg dry weight, and the $\alpha$-/${\gamma}$-tocopherol ratio from 0.40 to 0.75. Tocopherol content decreased by 18% but $\alpha$-/${\gamma}$-tocopherol ratio increased by 44% in roasted seeds. The results indicate that the level of tocopherol in Korean peanut varieties is moderate and the ratio of $\alpha$- to ${\gamma}$-tocopherol is low.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.33 no.s01
• /
• pp.64-85
• /
• 1988

Peanut seeds are characterized by high oils and proteins with good quality, and are utilized as an edible oil source and a protein-rich food products. The end products, being peanut butter, salted seed, confections, roasting stock and other by-products are favored in world-wide because of their unique roasted peanut flavor. As with many other foods, interest in the composition and chemistry of peanut is largely a result of thier use as human food. Thus, a more complete knowledge of thier chemical and food quality and flavor properties is desired. Literatures are reviewed mainly focucing on the physicochemical properties and nutritional quality of oil, protein and flavor in peanuts. Chemical properties of protein and oil, and volatile flavor component in peanut seeds are studied extensively in view point of chemical and food nutritional value. But in crop base, the synthesis and genetic studies of the chemicals could not provide valuable informations on the breeding for quality improvement. Some essential amino acids are limiting in peanut seeds and the tocopherols are very important in oil stability and for dietary adequacy ratio in high linoleic acid peanut oil, but it is thought to be quite difficult to improve by breeding technique as their lack information of gene actions. However, the selections of high protein and oil, and some essential amino acids and linoleic acid rich genotypes could be helpful for the quality improving. Research studies are also needed to elucidate the relationships between flavor components and consumer perception of peanut flavor.