• Korean Journal of Food Science and Technology
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• v.7 no.3
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• pp.159-167
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• 1975

Present work was conducted to investigate the combined effects of gamma-radiation and chemical treatment on the inhibition of sprouting and decay of potato tubers. Irish Cobbler, Apollo and Shimabara potato tubers were immersed in 1000, 2000 and 3000 ppm solution of salicylic acid for 2 minutes, and then irradiated at doses of 5, 10, and 15 krad using an indoor gamma room of approximately 10,000 Ci of $^{60}Co$. Treated tubers were stored for 8 months at room temperature. The results of this work are summarized as follows: 1. Moisture content of irradiated potato tubers was changed less than the control, and decreased gradually along with an extended storage period. Ascorbic acid content was remarkably decreased by gamma-radiation and an extended storage period. 2. Reducing sugar content of irradiated potato tubers tended to increase greatly compared with unirradiated potato tubers, however, starch content of irradiated potato tubers decreased compared with the control. Reducing sugar and starch content of all groups also decreased gradually along with an extended storage period. 3. The storageability of Irish Cobbler variety was best among three varieties and Shimabara variety was worst among them when gamma-radiation is treated singly or in combination with the chemical. Sprouting of potato tubers was more suppressed in combination treatment than single treatment. 4. Decay of potato tubers was more reduced in combination treatment than single treatment. Chemical treatment or gamma-radiation followed by chemical treatment had no influence on decay or spronting of potato tubers. 5. Weight loss of potato tubers was considerably increased as storage period became extended. Shrinkage was, more serious in Shimabara than in rish Cobbler.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.535-540
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• 1996

Potato slices were dipped in solution of 2% CaCl$_2$, and 1% chitosan or preheated in each of these solutions for refrigeration for 4 weeks at 5$^{\circ}C$. Changes in L value, content of total phenol and chlorogenic acid and po lyphenol oxidase activity were determined. During refrigeration, it was found that L values of potato slices treated with CaCl$_2$, (CaPS) and those treated with chitosan (ChPS) increased. Contents of total phenol and chlorogenic acid of potato slices decreased, While potato slices preheated in CaCl, solution (Hcaps) showed much decreases. And polyphenol oxidase (PPO) activity of potato slices decreased except CaPS and decreases in PPO activities were much larger in preheated potato slices. From these results, of those treatments used, chitosan treatment combined with preheating have shown to be effective to control enzymatic browning of potato slices during refrigeration.

• Korean Journal of Food Science and Technology
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• v.10 no.3
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• pp.320-330
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• 1978

Riced dehydrated potato granules with a good reconstituton quality was made from Irish Cobber (IC) and Shimabara which are representative varieties in Korea. A part of IC potato granules was packed in small vinyl-bags while the rest, including some BHA (75ppm)-treated granules, was packed in $301{\times}407$ plain tin cans. These granules were stored in a room at room temperature, and their physico-chemical properties and lipid composition were studied. The color of the granules was measured with a Hunter-type Tristimules colorimeter. L, $a_L,$ and $b_L-values$ were respectively 83.8, -1.1 and 18.3. Variety and package-type did not affect the color. In general, it was darker than that of commercial wheat flour, but whiter than that of commercial defatted soy flour. At $100^{\circ}C$, the granules, irrespective of variety and package-type, absorbed water rapidly, and reached the maximum moisture content of $90{\sim}92%$ in 3 min., whereas they absorbed water more slowly at $8{\sim}14^{\circ}C$, and reached the maximum content of $72{\sim}74%$ in 5 minutes. Peroxide, TBA, carbonyl, acid, and iodine values of the granules after 3 months storage were respetively $150{\sim}460\;meq/kg,\;20{\sim}26,\;154{\sim}380$ micromole, $24{\sim}59,\;and\;70{\sim}78$. Except iodine values, all the chemical values were affected by variety and package-type. Ether and $CHCl_3-extracts$ of the granules from IC and Shimabara were subjected to GLC and TLC analyses. In case of IC, the major fatty acids were palmitic, stearic, and oleic (30.0, 18.8, 40.6), while in case of Shimabara they were palmitic, oleic, and linoleic acids (26.7, 39.6, 23.4%). The major lipid classes were, in both cases, triglycerides and phospholipids. Their contents were raspectively 19.1 and 43.1 (IC), and 30.1 and 37.4% (Shimabara).

• Food Science and Preservation
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• v.13 no.4
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• pp.438-444
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• 2006

This study was carried out to obtain fundamental data such as peeling efficiency and quality of potatoes and sweet potatoes peeled by hand, machine and alkali(NaOH). The weight loss by peeling was influenced by peeling methods. Weight losses by rotational brushing-type peeler showed the lowest value, 7.9% in potato, and 7.3% in sweet potato. Any significant differences in moisture content were not found in potatoes and sweet potatoes by peeling methods. The pH of potatoes and sweet potatoes just after peeling were 5.8-6.8 and 6.23-6.63, and decreased somewhat until 3 hrs after peeling. Hardness of potatoes and sweet potatoes peeled by hand with fruit knife were better than that of others. Depending upon the peeling method used the color and color differences undergo some changes in their color and browning. Color difference value of peeled potatoes by hand with a technical tools, and by mechanical peeler such as rotational cutting-type peeler and rotational brushing-type peeler showed just slightly. In particular, changes of rotor differences value of potatoes and sweet potatoes peeled by dipping with 10% NaOH solution at $100^{\circ}C$ was the highest in the samples peeled by NaOH.

• Horticultural Science & Technology
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• v.30 no.5
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• pp.603-612
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• 2012

In order to select potato clones for making cold chip, this study analyzed the glucose content, acrylamide content, and the correlation between the two properties after harvest, $4^{\circ}C$ and $8^{\circ}C$ low-temperature storage, and $20^{\circ}C$ heating treatment of 47 breeding clones and control cultivars 'Atlantic', 'Sumi', and 'Gui Valley'. In all of the control cultivars and 47 clones, glucose content was below 0.25% and acrylamide content was below 1000 ppb just after harvest, but after $4^{\circ}C$ low-temperature storage both the glucose content and acrylamide content increased rapidly and only 4 clones H7, H13, H16, and H40 showed a level below 500 ppb. In $8^{\circ}C$ low-temperature storage as well both contents increased, but the increase was relatively smaller than that in $4^{\circ}C$ low-temperature storage. In addition, $20^{\circ}C$ heating treatment decreased both contents. In the results of analyzing the correlation between glucose content and acrylamide content at low-temperature storage, a positive correlation was observed. In conclusion, clones H7, H13, H16, and H40 showing low glucose content even at low-temperature treatment were found to contain less acrylamide and therefore they were selected as potato clones suitable for making cold chip.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.364-369
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• 1982

Two varieties of potatoes, Irish cobbler and Shimabara stored for seven and nine months respectively by irradiation combined with natural low temperature (year-round temperature change:$2{\sim}17^{\circ}C)$ on a batch scale were investigated on the suitability for processing of potato chip. Nine months after storage, irradiated potatoes (Irish cobbler) tended to maintain somewhat-better texture and sensory quality than untreated in potato chip processing. Peel rate, closely related to potato chip yield, of untreated potatoes were $20{\sim}25%$ higher than those of irradiated and Agtron color determination of potato chip from both irradiated were commercially acceptable. Preservation of potatoes by irradiation combined with natural low temperature was evaluated as an alternative method of the supply for raw materials of potato chip processing in the off season in Korea.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.247-255
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• 2016

This study was performed to investigate the effect of packaging materials on quality characteristics of washed potatoes such as Hunter's a value, chlorophyll and potato glycoalkaloids (PGA) content during their storage for 15 days. Packaging methods were evaluated into five ways: no packaging (NP, positive control), paper bag (PB, negative control), onion net (ON), transparent oriented to polypropylene without hole (TP), opaque oriented polypropylene with 4 holes (OP). Hunter's a values of washed potatoes showed minus in NP and TP after 12 days storage, whereas all plus values were observed in those of PB, ON, and OP. Total chlorophyll content of washed potatoes was the highest in no packaging at 15 days after storage. The PGA content of washed potatoes showed low levels in flesh part (below $5mg/100g{\cdot}FW$) as well as in peel part ($4.5-9.3mg/100mg{\cdot}FW$) in all packagings up to 15 days after storage.

• Food Science and Preservation
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• v.15 no.6
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• pp.847-851
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• 2008

The handling and processing of agricultural products in Korea is done manually. Small plastic boxes, nets, and corrugated cardboard boxes are used as containers during harvesting, sorting and other product handling operations. However, these practices are labor-intensive, time-consuming, require various kinds of packing materials, and are expensive because of high operating costs. To overcome these problems, the use of pallet bins with pre-cooling and storage features for handling and processing bulk farm products was investigated. The airflow resistances through bulk potato, onion and mandarin stocks were measured, and the pallet bins and a pressure pre-cooling device were manufactured. The opening ratio, bed depth and airflow rate through bulk potato, onion and mandarin in the pallet bin were defined with regression equations. The cooling rates of bulk potato, onion and mandarin were 0.8C/h ($21.7{\rightarrow}0C$, 14.5 h), 0.4C/h ($15.4{\rightarrow}.0C$, 32.2 h) and 0.7C/h ($13.7{\rightarrow}C$, 18.8 h), respectively, with the pressure pre-cooling system. Temperature deviances for storage of bulk potato, onion and mandarin were 0.12C, 0.12C and 0.17C, respectively.

• Applied Biological Chemistry
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• v.29 no.4
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• pp.352-358
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• 1986

The relationship between weight reduction and rehydration of dehydrofrozen potato was determined. At initial stage of dehydration sliced potato lost moisture rapidly. After drying for 2 hours weight reduction of sliced potato was 56% for Superior var., and 55% for Irish Cobbler. The empirical drying equations were obtained as follows: ${\frac{M-M_e}{M_o-M_e}}={\exp}(-0.4487\;{\theta}^{1.2328})$ and ${\frac{M-M_e}{M_o-M_e}}={\exp}\;(-0.4951\;{\theta}^{1.1949})$ for Irish Cobbler and Superior, respectively, where $M_o$, $M_e$, and M are dry base moisture content(%) of initial, equilibrium and at time ${\theta}$ in hour, respectively. With the decrease of weight above 50%, the rehydration rate decreased sharply and the color index L value also decreased while a and b increased. Lightness of dehydrofrozen potato decreased slightly and rehydration rate remained constant during storage at $-18^{\circ}C$. The sulfite treatment led to increase of L value and decrease of a and b values.

• Korean Journal of Food Science and Technology
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• v.4 no.1
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• pp.29-35
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• 1972

Effects of various dosages of gamma ray ranging from 0 to 16 krad on sprout inhibition and nutritive value of potato tubers were investigated with Irish Cobbler variety. Sprout growth was gradually suppressed with increasing dosage, and completely inhibited with 16 krad treatment. Under this optimum dosage, weight loss of tubers was markedly reduced and tubers kept firm throughout the 2 month storage period. Irradiation had no adverse effects on the cooking quality of potato tubers. Moisture content of stored potato tubers was shown to be in inverse proportion to sprout growth. Tubers treated with 16 krad tended to contain somewhat higher percentage of total carbohydrate than those treated with lower dosages. Significantly larger amounts of ascorbic acid were retained in 8 and 16 krad treatments than in 0 and 2 krad treatments.