In order to examine how much AN is eluted from PAN-containers having different residual AN(RAN) concentrations in the material there of into alcoholic beverage, and in order to examine the influences of different container volumes on the elution, AN eluted from three kinds of PAN-containers (2,400ml, 1,000ml and 500ml) was investigated at 40℃for 10 to 90 days, using food simulating solvents; 20 %, 35%, 50 %, 65 % ethanol. 　The results of the analysis showed that the amount of AN eluted from the PAN-containers was decreased in the order of 65%, 50%, 35%, 20% ethanol. The amount of AN eluted from the PAN-container of 2,400ml having a RAN concentration of 1.0 µg/g in the material and 1,000ml having a RAN concentration of 0.2 µg/g in the material thereof into 65% ethanol was individually below the lower limit of detection under the severe storage conditions of 40℃ for 90 days. In the 500ml PAN-container, a RAN concentration in the material has to be more less than 0.3 µg/ g. 　The lower limit of detection of eluted AN was 0.005 µg/ml.

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Using 'Le Lectier' pears following after-ripening, examination was made of any preventive condition for internal browing occuning during storage and any simple method of storage. Internal browing was more liable to occur for more advanced after-ripening and for higher storage temperature. CA storage, however, caused no internal browning at all at a gas composition of 0₂ 3 % and C₂ 0 %. Then, in order to make simple formation of such a gas environment, fruits were film pack-stored with commercial CO₂ absorbent material (2ℓ CO₂ absorption/ a piece of absorbents), and proper packaging condition proved to be 60 µm-thick low-density polyethlene film packaging with a film area of ca.1000cm²／kg fruit. Storage at 0℃for 45 days under this condition caused an equilibrated intra-packaging gas composition of 0₂ 2.5～3 % and CO₂ 0 %. Internal browning rate was 7 %, representing practically surfficient quality fruits. On the other hand, gas analysis of fruits revealed that internal browning of fruits developed upon massive accumulation of CO₂ in the pulp or the core tissue.

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　An optimum cushioning design method for reducing the cushion volume and for properly designing the cushion shape has been Firstly, the present optimum design method was modified to be applicable to products with protuberance. Secondly, the effect of the protuberance length on the optimum shape of cushions calculated by this newly developed design method was investigated 　The results are summarized as follows. (1) The protuberance length shorter than a certain value does not affect the optimum shape of cushion. (2) The thickness and the volume of cushion as well as the cost of packaging materials increase linearly with the length of protuberance. On the other hand, the strain decreases linearly with the length of protuberance. (3) The strain of cushion required for minimizing its volume is larger than that required for maximizing its thickness. Furthermore, the area of cushion and the cost of packaging material at minimum volume is smaller than those at maximum thickness. (4) The height of products dose not affect the optimum shape of cushion.

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Thermal processing is a most commonly used method for extending the shelf ｌｉｆe oｆ processed food. The heat ｓｔｅrilization of foods in cans or retortable pouches has been conducted conventionally by heating the food container in a pressurized stem or hot-water retort at predetermined temperature and time. Although this process will certainly make microorganism and spores inactive, it may cause destruction of essential nutrients that leads to deterioration of product quality. Under these circumstances the significant point is to find out the condition for the maximum nutrient or quality retention as well as the sufficient bacterial reduction required for stable and safe products. For this purpose, ｉｔ ｉs ｖｉｔａllｙ important to find out the optimum temperature profile and its effect on product quality. With ａ view to predict the effect of various temperature profiles with an equal sterilizing value on quality retention, a model was constructed to simulate the thermal processing of foods packed in retortable pouches. Five types of retort temperature proｆｉｌes were selected that are conventionally used in thermal processing of food industry. This paper presents an optimum report temperature profile obtained by computer simulation. It was found that a trapezoid-type temperature profile is the best one among these five types of profiles

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