• 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.

• Research in Plant Disease
• /
• v.8 no.2
• /
• pp.92-100
• /
• 2002

For the survey of viruses infected in peanut cultivated in Korea, peanut seeds and leaves showing viral symptoms were collected from their growing areas. Typical symptoms on virus infected peanut leaves including mosaic, mottle with necrosis, yellowing, stripe or vein banding and stunts were observed. Two viruses isolated from the naturally infected peanuts were identified as Bean common mosaic virus(BCMV-PSt) and Peanut mottle virus(PeMoV) by their host range, immunosorbent elcetron microscopy(ISEM), direct immuno staining assay(DISA), RT-PCR, and intracellural symptoms. Direct negative staining method by electron microscope showed filamentous particles of about 780 m in length as well as inclusion bodies. In ultrathin sections of BCMV-PSt and PeMoV infected tissues, cytoplasmic cylindrical inclusions as well as filamentous virus particles were observed in the cytoplasm of parenchyma cells. ISEM revealed filamentous particles strongly decorated with antiserums of BCMV-PSt and PeMoV Peanut seeds were stained with BCMV-PSt and PeMoV antisera indicating the possibility of seed transmission far these viruses. Seedlings germinated from peanut seeds which reacted with antiserums of BCMV-PSt by DISA showed mild mottle or stripe symptoms while mosaic and necrotic mottle symptoms were observed for PeMoV-positive seedlings. Filamentous particles were strongly decorated with each antiserum under ISEM observation. BCMV-PSt coat protein gene of about 1.2 Kbp was amplified by RT-PCR. Altogether these results indicate that BCMV-PSt is the most prevalent virus infecting peanut in Korea.

• Korean Journal of Food Science and Technology
• /
• v.38 no.2
• /
• pp.309-312
• /
• 2006

Aflatoxin $B_1$ in 70 retail samples, including 40 food-grade peanut (28 domestic, 12 imported) and 30 peanut butter (12 domestic, 18 imported) samples, was analyzed by high-performance liquid chromatography (HPLC) with fluorescence detection (FD), and positive samples were confirmed using HPLC with mass spectrometry (MS). Recoveries of aflatoxin $B_1$ spiked at 2 ppb exceeded 80% in both commodities. Detection limits for aflatoxin $B_1$ by HPLC-FD and MS analysis were 0.8 and 0.1 ppb, respectively. Four domestic and six imported peanut samples contained detectable levels of aflatoxin $B_1$ with means of 19 and 32 ppb, respectively. Aflatoxin $B_1$ was found in two domestic and three imported peanut butter samples with mean aflatoxin $B_1$ of 10 and 12 ppb, respectively. Peanut commodity showed more frequent aflatoxin $B_1$ contamination compared to its processed peanut butter product, and levels of aflatoxin $B_1$, especially in imported peanuts, were significantly (p<0.05) higher than those of other commodities. These results suggest peanut and peanut butter are not major contributors to dietary intake of aflatoxin $B_1$ in South Korea.

• Food Science and Preservation
• /
• v.17 no.3
• /
• pp.384-390
• /
• 2010

To assess the potential of peanut sprouts as a functional food material, the germination rate, resveratrol content, and nutritional components of sprouts were analyzed. Of all samples tested, Gyeong-buk peanuts had the highest germination rate. The resveratrol content was higher in peanuts than in peanut sprouts. The resveratrol level in Gyeong-buk peanut sprout ($15.5{\mu}g/g$) was the greatest of all tested samples. The cotyledon of Gyeong-buk peanut sprout had the highest resveratrol content ($24.89{\mu}g/g$), followed by the roots ($12.66{\mu}g/g$), but resveratrol was not detected in the stems. The levels of moisture, crude protein, crude fat, ash, and carbohydrate in Gyeong-buk peanut sprout were 6.69%, 35.58%, 33.08%, 2.96%, and 21.96% (all w/w), respectively, in dried material. Compared with peanuts, peanut sprouts contained higher protein levels, and a lower content of crude fat, but showed a minimal difference in mineral content. The amino acid content of peanut sprouts (2,551.8 mg/100 g) was higher than that of peanuts (87.89 mg/100 g). Specifically, the asparagine content of peanut sprouts (834.54 mg/100 g) was the highest of all amino acids. Saturated fatty acids, including myristic and palmitic acids, were detected in peanuts, and the levels of unsaturated fatty acids such as oleic (31.19 g/100 g) and linoleic acids (39.24 g/100 g) in peanut sprouts were higher than those of other fatty acids.

• Food Science and Preservation
• /
• v.22 no.5
• /
• pp.660-665
• /
• 2015

This study was conducted to evaluate the effects of peanut (Arachis hypogaea L.) powder on the physicochemical and sensory characteristics of Jook. The proximate composition of peanut powder was as follows: moisture, 1.8%; crude protein, 24.9%; crude lipid, 48.3%; crude ash, 2.9%; and carbohydrates, 22.1%. Each sample of Jook contained 20%, 40%, 60% and 80% of peanut powder when compared to the control, and their physicochemical properties were assessed. As the peanut powder content increased, there was a significant decrease in pH (p<0.05) In addition, Hunter's color L value decreased, whereas Hunter's color a and b values increased with increasing addition of peanut powder. The Jook showed lower spreadability and higher viscosity values as the peanut powder content increased. The results of the sensory evaluation showed that the Jook containing 40~60% peanut powder had the highest score. According to the overall preference, addition of 40% peanut powder positively affected the quality characteristics of Jook. These results suggest that peanut powder can be applied to Jook to achieve beneficial effects on the quality and functionality.

• Korean Journal of Medicinal Crop Science
• /
• v.28 no.1
• /
• pp.21-28
• /
• 2020

Background: Owing to its high efficiency in lipid and protein production, peanut (Arachis hypogaea L.) is considered one of most important crops world-wide. The kernels of peanuts are undoubtedly the most important product this plant, whereas the skin is almost completely neglected in nutraceutical terms. However, peanut skin contains potentially health-promoting phenolics and dietary fiber, and there is considerable potential for commercial exploitation. In this study, we evaluated the α-glucosidase inhibitory activity of an extract of peanut skin (PS). Methods and Results: The α-glucosidase inhibitory effects of 80% ethanol extracts of peanut (A. hypogaea L. 'Sinpalkwang') skin were evaluated and found to have a half-maximal inhibitory concentration (IC₅₀) value of 1.2 ㎍/㎖. Progress curves for enzyme reactions were recorded spectrophotometrically, and the inhibition kinetics revealed time-dependent inhibition with enzyme isomerization. Furthermore, using ultra-high performance liquid chromatography combined with quadrupole-orbitrap mass spectrometry, we identified 26 compounds in the peanut skin extract, namely, catechin, epicatechin, and 24 proanthocyanidins. Conclusions: The results suggest that peanut skin can be utilized as an effective source of α-glucosidase inhibition in functional foods and nutraceuticals.

• Korean Journal of Plant Resources
• /
• v.24 no.3
• /
• pp.272-279
• /
• 2011

It is very crucial to evaluate the genetic diversity of peanut genetic resources for identification of peanut germplasm accessions and variety improvement. Cultivated peanut generally has two subspecies, hypogaea and fastigiata. In this study, we identified peanut into three plant types, virginia (var. hypogaea), spanish (var. vulgaris), and valencia (var. fastigiata). Former one belongs to ssp. hypogaea and latter two are involved in ssp. fastigiata. Twenty SSR markers were used to assess the genetic variation of three sets, hypogaea, vulgaris, and fastigiata, respectively. Out of variety-specific SSR primers tried in this study, ten pairs of SSR primers showed polymorphisms. Each accession could be identified by a specific set of polymorphic SSR primers, and allele number was evaluated among accessions, with an average of 6.7 in var. hypogaea and 5.4 in var. vulgaris and fastigiata. For evaluation of genetic diversity, gene diversity ranged from 0.336 to 0.844 and PIC (polymorphism information contents) ranged from 0.324 to 0.827 were investigated. Dendrograms based on genetic distances were constructed, which showed the existence of three different clusters. And these three different clusters might be associated with the genes involved in three plant types. The results also suggested that there were plentiful SSR polymorphisms among peanut germplasm accessions in RDA (Rural Development Administration, Korea) Genebank and SSRs might play an important role in evaluating peanut accessions and cultivar improvement.

• The Korean Journal of Mycology
• /
• v.51 no.4
• /
• pp.383-387
• /
• 2023

Peanut plants showing mild wilt were found in fields of Iksan, Korea, in August 2021. The diseased peanut plants were collected, and the causal pathogens were isolated using potato dextrose agar (PDA) medium. The isolated IS-1 strain formed white mycelia on PDA, which turned black with age. Sclerotia were produced on the PDA and barley leaves laid on water agar 7 d after incubation at 30℃. The sequences of both the internal transcribed spacer (ITS) region and calmodulin gene of IS-1 showed a 100% similarity with that of Macrophomina phaseolina. A phylogenetic tree constructed using the ITS regions of fungal pathogens causing disease in peanut plants indicated that the IS-1 stain belongs to M. phaseolina. The inoculation of IS-1 sclerotia into peanut seedlings resulted in yellowing and wilt symptoms in aboveground plants and brown to dark rots in roots 35-40 d after inoculation. Overall, the morphological characteristics, molecular identification, and pathogenicity of IS-1 indicate that the causal pathogen is M. phaseolina. This is the first report of charcoal rot caused by M. phaseolina on peanut plants in Korea. Further study is needed to develop the control measures for charcoal rot in peanut plants.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.30 no.3
• /
• pp.439-443
• /
• 2001

The effect of fermentation of peanut milk with lactic acid bacteria on n-hexanal content was investigated. Changes in pH, titratable acidity and viable cell populations indicated that Streptococcus salivarius subsp. thermophilus was adapted better than Lactobacillus delbrueckii subsp. bulgaricus during fermentation. Analysis of headspace volatiles revealed that n-hexanal, which is one of the compounds responsible for undesirable green/beany flavor in peanut milk, completely disappeared as a result of fermentation. S. salivarius subsp. thermophilus was more effective than L. delbrueckii subsp,. bulgaricus in reducing the n-hexanal content. No significant difference was found in water sorption between fermented and unfermented peanut milk.

• KSBB Journal
• /
• v.31 no.1
• /
• pp.14-19
• /
• 2016

To investigate the effect of peanut sprout extract on skin care, we measured anti-oxidant activity and whitening action. As a result of measuring DPPH radical scavenging activity to examine independent anti-oxidation of peanut sprout extract, there was strongly scavenging activity. Fluorescent material DCF-DA was used to measure hydrogen peroxide created in RAW 264.7 cells, and all concentration dependently decreased ROS production. As a result of measuring nitric oxide to examine anti-inflammation of peanut sprout extract, there was strongly inhibited nitric oxide production in RAW 264.7 cells. Tyrosinase activation was found to inhibited dose-dependant. Melanin production was also prevented dose-dependant. Therefore, it is expected to be used effectively in development of functional cosmetic materials.