Microbial populations (total bacteria, lactic acid bacteria and coliforms), TBA, VBN and POV were investigated for evaluating the shelf life of pork loins gamma-irradiated at doses of 1, 3, 5 and 10 kGy with air-contained and vacuum-packaged methods. The initial microbial populations decreased with gamma irradiation depending upon the dose and microorganisms in the vacuum-packaged samples were inhibited more than those in the air-contained samples. POV, TBA and VBN values were higher in the air-contained samples than in the vacuum-packaged samples. In conclusion, the combination of gamma-irradiation and vacuum-packaging could extend the shelf life of chilled pork loin.

전분 추출용으로 대부분 사용되고 있는 도토리 종실의 가해해충 사멸방법을 연구할 목적으로 현행 검역해충 사멸방법인 methyl bromide (MBr) 훈증처리와 감마선 조사법에 대하여 살충효과와 이들이 몇 가지 이화학적 품질에 미치는 영향을 비교 검토하였다. 국내산 도토리의 가해해충은 도토리밤바구미 (Curculio drntipes Roelofs)와 복숭아명나방 (Dichocrocis punctiferalis Guenee)으로 확인되었다. 이들

Chestnuts(Castanea cretana, Eunki) were used for quality evaluations from the physiological and physicochemical points of view during storage under different temperatures and relative humidities for 8 months. Quality criteria included spouting, rotting, weight loss, and the changes in moisture, total sugar, reducing sugar, and total vitamin C of the stored sample. Sprouts(roots) were developed in about 2 months in all stored samples which had been mixed with sawdust(50% moisture) and stored under the conditions of 2∼25 and 62∼95% RH. The sprout development was more significant in the storage temperature of Pit(96, 805% RH, PT)and room(167, 8510% RH, RT) than low(31%, 805% RH, LT)and ambient(1411, 675% RH, AT). The rates of rotting and weight loss were appreciable in the order of PT, AT, RT and LT, and those of LT were 1∼2%. The use of wet sawdusts resulted in the increase of moisture contents in stored samples, thereby causing the rotting phenomena. Some chemical components of stored samples were found liable to the changes according to storage conditions, that is; total sugars showed a decreasing tendency along with a temporary increase during storage, and both reducing sugar and vitamin C were similarly accumulated in the samples stored at low temperature conditions. The results indicated that long-term storage of chestnuts will be possible in either cases of the application of low temperature following sprout-inhibition treatment or the use of lower temperature than 0 to suppress its sprouting during storage.

In order to develovpment of new sterilizing method applied to food industry, effects of ozone treatment on microorganisms, associated with food hygiene were investigated. Microorganisms were immersed in water and sparged with ozonised air(ozone concentration, 3mg liter-1) at an air flow rate of 5 liter min-1. When organisms were treated with benzoic acid and sorbic acid of 0.4∼1.0g/, respectively, they were not dectable perfectly. Sodium benzoate had an effect on Penicillium islandicum. When bacteria were sparged with ozonised air, Pseudomonas aeruginosa completely inhibited at 60 minutes, and the killing Aspergillus flavus and Penicillium islandicum. Also, all of bacteria were inactivated after immersed with ozonated water for 10minutes, but two fungal species were not effective.

Potatoes, Irish cobbler, were subject to quality evaluation from the physiological and physicochemical points of view during storage under different temperatures and relative humidities for 11 months. Quality criteria were sprouting, rotting, weight changes, moisture, total sugar, reducing sugar and vitamin C. Low temperature condition(LT, 2∼4, 80% RH) was enough to preserve Potatoes for 11 months, but it was indicated to be limitations that the increase in reducig sugar as well as sprouting by about 3.3 to 6.7% occurred from the 3rd month of storage. Meanwhile, pit temperature(PT, 3∼15, 75∼85% RH), room temperature(RT, 7∼17, 80∼95% RH) and ambient temperature(AT, 2∼25, 62∼72 RH) were shown infeasible conditions for the storage of potatoes mainly due to the increase In sprouting-rate and subsequent quality-loss after 3 months of storage. Based on the results, it proposed that more economical conditions, ranging 10 to 15 and about 80% RH following sprout inhibition treatment should be used for the long-term storage of potatoes.

Organoleptic qualities were evaluated putting emphasis on flavor and color of white ginseng powders which were treated with ethylene oxide(EO) and gamma radiation(5, 10kGy) for microbial decontaminations. Immediately after treatments, there was no significant changes in the overall flavor and color of the samples between the nontreated control and both treatments. The color of even airtight-packaged samples, however, was changed(p2 when treated with EO and 10 kGy. These changes in color were confirmed by the instrumental determinations for the stored samples. Thus, it can be proposed that gamma Irradiation below 10kGy combined with airtight packaging is required for keeping the organoleptic quality of white ginseng powders for more than 6 months of storage.

For the purpose of improving microbiolgical quality of carrot powder, which is being used as minor ingredients of convenience foods, comparative influence of Υ-irradiation and ethylene oxide(E.O) fumigation was investigated with emphasis on sterilizating effect and physicochemical propertied Carrot powder sample was contaminated with thermophiles 4.0103/g, acid tolerant bacteria 3.7103/g and coliforms 1.6102/g, respectively. And thus sanitation process was required. E.O fumigation in commercial practice was not enough to destroy thermophilic bacteria, while Υ-irradiation at below 5 kGy could reduce all microorganisms up to undectected levels. Radiosensitivity(D10) of thermophiles was shown to be 2.25 kGy. The applicable dose of irradiation to the improvement of microbiological quality showed insignificant influences on the physicochemical quality of the sample.