• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.198-198
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• 2017

Cultivated varieties of sweet potato were from dry texture type to tender texture type on the basis of consumer preferences. There are many differences in the quantity of sweet potato, starch content, pigment, and sugar content depending on the cultivation season and area, even in the same variety. Therefore, in this study, we attempted to establish optimum time of harvesting through growth characteristics and variation in component like starch, sugar, polyphenol and flavonoid. Four sweet potato varieties were used in this experiment. Among them, Jinhongmi (JHM) & Yulmi (YM) were as dry texture type and Pungwonmi (PWM) & Hogammi (HGM) were as tender texture type. Sweet potatoes were transplanted on 23 May, 2016 and were investigated storage root weight and component contents every 20 days from 60 days to 120 days and surveyed yield at 110, 120, 130 days after transplantation. Result revealed that storage root weight of YM, JHM, and HGM were 30.1, 38.9, 20.8 g respectively in 60 days after transplanting. Storage roots of PWM gerw faster with the weight of 88.2 g. In 120 days after transplanting, storage root weight varied from 88.3 to 118.7 g, HGM was the smallest, and PWM was the largest. Sugar contents of sweet potato ranged from 21.0 to $23.8Brix^{\circ}$ in 60 days after transplanting and from 27.5 to $30.78Brix^{\circ}$ in 120 days after transplanting. In particular, the sugar content of HGM was the highest over $30Brix^{\circ}$ after 80 days. The starch content of dry texture type (YM, JHM) increased from 15.5% to 20.4% and tender texture type (PWM, HGM) increased from 11.0% to 17.3%. Starch content tended to be high in dry type sweet potatoes. The content of polyphenol and flavonoid were highest in 60 days after transplanting and was reduced according to cultivation period. The total yield of PWM was high as 3,154 kg/10a and large storage root of over 250 g accounted for 47.4% in 110 days after transplanting. Storage root (YM, JHM, HGM) of 81~150 g accounted for 34.9% ~ 43.2% in 120 days after transplanting. These are the most marketable. Because consumer in Korea prefers small, round and about 100g size sweet potato. The ratio of large storage root (over 250 g) were increased in all varieties at 130 days after transplanting. Therefore, it is considered appropriate to harvest PWM at 110 days and YM, JHM, HGM at 120 days after transplanting, which planted in late May.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.39-39
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• 2017

In Asia, sweet potato (Ipomoea batatas) is a very important crop for starch production. Approximately 74.3% of the total sweet potato production quantity is produced in Asia (FAO, 2014) and China is the largest producer of sweet potato. Post-harvest management is particularly important because it is difficult to maintain the quality as well as quantity of sweet potatoes. Despite the importance of post-harvest management, researches on sweet potato have been focused on production-related study such as breeding of new variety, improved techniques of cultivation, so there is limited research on storage after harvest. Curing is a normal practice after sweet potato harvest to promote wound healing and extend postharvest storage life. In Korea, harvested sweet potatoes are usually cured for 4 to 7 days at $30-33^{\circ}C$ and 80-95% relative humidity within one week. Since the optimum storage temperature of sweet potato is regarded as $15-20^{\circ}C$, additional facilities and costs are required to raise the temperature for curing. However, the majority of small farmers do not have the capacity to provide additional facilities and costs. This study was initiated to suggest a new curing method to accelerate the wound healing by applying chemical oxidation to the wound surface of sweet potato. Oxidative stress is known to play an important role in the synthesis of secondary metabolites including lignin. In addition, chemical oxidation can be applied to prevent spoilage caused by microorganisms. Powerful gaseous oxidant with excellent penetration ability and superior sterilization effect was selected for this study. Lignification, weight loss, and spoilage rate of artificially wounded sweet potatoes were investigated after oxidant fumigation. There were clear differences in morphological analysis such as lignification pattern, lignin deposition color, and continuity of lignified cell layers between oxidant-fumigated sweet potatoes and control. These results show that gaseous oxidant can be used to supplement or replace the curing practice, to improve shelf-life as well as curing cost reduction.

• 한국식품저장유통학회지
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• 제31권1호
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• pp.33-45
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• 2024

Three spring potato varieties (Atlantic, Chubaek, and Superior) were cultivated for 80, 90, and 100 days and compared in terms of their total and marketable yields and specific gravities. Subsequently, changes in the quality parameters (weight loss, sprouting rate, disease incidence, dry weight, and specific gravity) of potatoes cultivated for 100 days were monitored during two-month storage in improved and semi-underground warehouses at 4℃ and room temterature. The productivities of Atlantic, Superior, and Chubaek were maximized at cultivation periods of 100, 100, and >90 days, respectively. In all cases, cold storage resulted in <5.3% weight loss and no marketability loss. However, two-month room temperature storage resulted in pronounced marketability loss due to weight loss (6.2, 7.3% and 10.9% for Atlantic, Superior, and Chubaek, respectively) and sprouting (in ~13%, >75%, and 99% of Atlantic, Superior, and Chubaek tubers, respectively). The marketability of Atlantic, Superior, and Chubaek during cold storage was maintained for >2, ~2, and <2 months, respectively. All varieties were characterized by rapid sprouting, low dry weight and specific gravity, and rapid marketability loss during storage.

• 한국식품영양과학회지
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• 제46권6호
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• pp.744-750
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• 2017

본 연구에서는 240일간 저장한 네 가지 품종의 감자를 Bacillus subtilis로 발효한 후 제조한 감자 칩의 아크릴아마이드 함량과 색도 변화를 알아보고자 하였다. B. subtilis에 의한 단시간 발효는 모든 품종의 감자 슬라이스로부터 유리된 환원당 제거에 효과적이었으나 총당 함량 감소에는 영향을 미치지는 않았다. 또한, 새봉과 진선 감자 슬라이스 내 존재하는 아스파라긴 함량도 감소하였다. 이러한 결과는 복합적으로 감자 칩의 아크릴아마이드 생성량과 색 형성에 영향을 미쳤다. 대서를 제외한 나머지 세 품종은 모두 83% 이상의 아크릴아마이드 감소율을 보였다. 따라서 본 연구는 B. subtilis에 의한 단시간 발효를 통하여 저장감자를 가공식품으로 활용할 수 있는 방안을 제시하고 있다.

• 한국환경농학회지
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• 제35권4호
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• pp.247-255
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• 2016

BACKGROUND: Acrylamide (CAS No. 79-06-1) is known to be a carcinogenic compound, and is classified as a Group 2A compound by the International Agency for Research on Cancer (IARC, 1994). Acrylamide can be generated during the browning process via the non-enzymatic Maillard reaction of carbohydrates such as reducing sugars and of amino acids such as asparagine, both of which occur at a temperature above $120^{\circ}C$. Potato tubers contain reducing sugars, and thus, this will affect the safety of processed potato products such as potato chips and French fries. In order to reduce the level of acrylamide in potato processed products, it is therefore necessary to understand factors that affect the reducing sugar content of potatoes, such as environmental factors and potato storage conditions, as well as understanding factors affecting acrylamide formation during potato processing itself. METHODS AND RESULTS: Potatoes were cultivated in eight regions of Korea; For each of these different environments, soil physico-chemical characteristics such as pH, electrical conductivity, total nitrogen, available phosphate, and exchangeable cation content were measured and correlations with potato reducing sugar content and potato chip acrylamide levels were examined. The reducing sugar content in potato during storage for three months was determined and acrylamide level in potato chip was analyzed after processing. The storage temperature levels were $4^{\circ}C$, $8^{\circ}C$, or $10^{\circ}C$, respectively. The acrylamide content of chips prepared from potatoes stored at $10^{\circ}C$ or $20^{\circ}C$ for one month was analyzed and the different frying times were 2, 3, 5, and 7 min. CONCLUSION: This study showed that monitoring and controlling the phosphate content within a potato field should be sufficient to avoid producing brown or black potato chips. For potatoes stored at low temperatures, a reconditioning period ($20^{\circ}C$ for 20 days) is required in order to reduce the levels of reducing sugars in the potato and subsequently reduce the acrylamide and improve chip coloration and appearance.

• 한국식품영양학회지
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• 제23권1호
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• pp.23-29
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• 2010

Pigment concentrates with violet-red color and sweet taste were obtained from purple-fleshed sweet potato(PFSP) using ethyl alcohol and water. Extract from general potato(GP) were used as a control. The relative stability of PFSP pigment concentrate(PFSPPC) in a storage test over 15 days was confirmed in the order of dark > fluorescence > sun-light irradiation. The relative stability of GP pigment concentrate(GPPC) in a storage test over 15 days was confirmed in the order of sun-light > fluorescence > dark storage. The RRP of PFSPPC was higher than that of GPPC, but the color strength of GPPC was 1/2 that of PFSPPC. Treatment of PFSPPC with aluminum potassium sulfate(0.2~0.3%, w/w) best improved its stability. The improved RRPs of PFSPPC were 45.16~47.31% in sun light irradiation, 55.91~60.22% in fluorescence irradiation, and 76.34~75.97% in dark storage conditions. In substituting aluminum potassium sulfate for chitosan, an amount of 0.2~0.3%(w/w) was suitable, giving similar results in improving pigment stability for all concentrates tested. Also, freeze-dried PFSPPC powder was manufactured as a substitute for dextrin, and also as a substitute for chitosan to the extent of 0.25%(w/w). The results of storage stabilite for freeze-dried PFSPPC and GPPC powder over 15 days, irradiation were, PRRs of 74.47~89.36% and 61.54~76.92%, respectively. The stability improving effect of freeze dried PFSPPC powder was confirmed by the results of storage experiments at various conditions. The use of freeze-dried PFSPPC powder was therefore confirmed to be an effective treatment for general foods.

• 한국식품저장유통학회지
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• 제14권1호
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• pp.8-17
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• 2007

수도수(TW), 0.85% 식염수(0.85% NaCl) 및 0.5% Sodium metabisulfite(0.5% SMS)를 대조구로 하고 강산성 전기분해수(SAEW ; Strong Acidic Electrolyzed Water, pH 2.53, ORP 1,088 mV, HClO 91.25 ppm)와 약알칼리 전기분해수 (LAEW ; Law Altaline Electrolyzed Water, pH 8.756, ORP 534 mV, HClO 105.70 ppm)를 침지액으로 하여 박피 감자와 고구마의 초기품질 및 $5^{\circ}C$ 저장중 품질변화를 비교 검토하였다. 저장중 총페놀성 화합물 함량 변화는 감자에서는 처리구간 차이가 거의 없었으나 고구마에서는 LAEW 침지 박피 고구마가 다소 낮은 경향을 나타내었다. PPO 활성은 저장기간 전반에 걸쳐 전기분해수 침지구인 SAEW 및 LAEW 침지 박피 고구마가 상대적으로 낮은 활성을 나타내었다. 색차 변화량과 조직감의 감소량은 전기분해수 침지 박피 감자와 고구마가 TW, 0.5% NaCl 및 0.5% SMS 침지 박피 처리구에 비해 상대적으로 작았다. 총균수와 대장균 군수는 저장초기 및 저장 3-6일까지는 전기분해수와 0.5% SMS 침지 박피 감자와 고구마가 생대적으로 낮은 균수를 나타내었으며, 관능평가 결과 종합적 기호도는 저장기간 전반기인 9일 정도까지는 LaEW가 타 처리구에 비해 다소 높게 평가되었으나 유의적 차이는 거의 없었다.

• Asian-Australasian Journal of Animal Sciences
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• 제25권9호
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• pp.1329-1337
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• 2012

This study was conducted to evaluate the effects of adding purple-fleshed sweet potato (PFP) powder on the texture properties and sensory characteristics of cooked pork sausage. Sodium nitrite alone and sodium nitrite in combination with PFP were added to five different treatments sausages (CON (control) = 0.01% sodium nitrite, SP25 = 0.005% sodium nitrite and 0.25% purple-fleshed sweet potato powder combination, SP50 = 0.005% sodium nitrite and 0.5% purple-fleshed sweet potato powder combination, PP25 = 0.25% purple-fleshed sweet potato powder, PP50 = 0.5% purple-fleshed sweet potato powder). The sausages were cooked to $74^{\circ}C$, stored at $4^{\circ}C$ for 6 wks, and used for chemical analysis, textural properties, and a sensory evaluation on 0, 2, 4 and 6 wks of storage, respectively. Similar CIE $a^*$ and $b^*$ values were determined in sausages from CON, SP25 and SP50 at the end of storage, and they were higher in CIE $a^*$ but lower in CIE $b^*$ than that of the PP25 and PP50 sausages. Significant differences were observed for brittleness and hardness when PFP was added to the sausages but were not confirmed after 4 wks of storage. The objective color score was influenced by adding PFP; however, the effect was not dose dependent. In overall acceptability, panelists favored the CON, SP25, SP50, and PP50 sausages but did not prefer PP25 sausages at the end of storage. Therefore, adding PFP to cooked pork sausages improved color and texture properties and sensory characteristics, but further study is needed to determine the proper ratio of sodium nitrite and PFP.

• The Plant Pathology Journal
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• 제16권6호
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• pp.318-320
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• 2000

Potate tubers with slver scurf lesions were collected from the cold storage at Pyungchang, Kangwon province in Korea. The causal agent of the silver scurf was identified as Helminthosporium solani by mycological characteristics of conidia and conidiophores. Pathogenicity of the fungus was confirmed by artificial inoculation on the potato tuber. This is the first report of potato silver scarf by Helminthosporium solani in Korea.

• 한국식품과학회지
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• 제14권4호
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• pp.364-369
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• 1982

감마선 조사(照射)와 자연저온(自然低溫)에 의한 감자의 상업적(商業的) 저장법(貯藏法) 개발(開發)을 목표(目標)로 제일보(第一報)와 같은 방법으로 Irish cobbler와 Shimabara 품종(品種)을 7개월(個月) 및 9개월간(個月間) 각각(各各) 저장(貯藏)하면서 potato chip 제조적성(製造適性)에 대한 실험(實驗)을 한 결과(結果)는 다음과 같다. 1. 9개월간(個月間) 저장(貯藏)한 Irish cobbler로 제조(製造)된 potato chip은 기계적(機械的) 및 관능검사결과(官能檢査結果) 대조구(對照區)가 무처리구(無處理區)보다 우수하였다. 2. Potato chip 수율(收率)에 영향이 큰 제피율(除皮率)에 따른 손실은 무처리구(無處理區)가 조사구(照射區)보다 $20{\sim}25%$ 높았다. 3. 단경기(端境期)에 있어서 potato chip 가공원료(加工原料)로써 방사선(放射線)과 자연저온(自然低溫)에 의하여 저장(貯藏)된 감자가 적당하였다.