Lactobacillus plantarum NCIMB 8826 strain was used as a model for succinic acid production by means of metabolic rerouting. Since this strain is the same as L. plantarum WCFS 1 whose genome has been completely analyzed, it is suggested that NCIMB 8826 strain possesses a potential succinic acid biosynthesis pathway. NCIMB 8826 strain produced a small mount of succinic acid grown in MRS medium in the presence of sodium bicarbonate. This means that the succinic acid biosynthesis pathway of this strain functions. In order to improve the potential of the succinic acid production, a pyruvate carboxylase of this strain was over in NCIMB 8826. However no remarkable increase of succinic acid production was observed, and the main product was still lactic acid. When a D-LHD and L-LDH double knocked-out mutant, which is a derivative mutant from NCIMB 8826 strain, was grown in MRS medium in the presence of sodium bicarbonate, a 12-fold amount of succinic acid was produced compared with that produced by the wild strain.

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In this study, the aroma characteristics of steamed sweet potato were compared with those of apple juice and the difference was clarified by sensory evaluation and odor sensor and electroencephalographic analyses. Although apple juice aroma was evaluated to be pleasant by all seven subjects, the same tendency was not observed for all the subjects on the electroencephalogram. Three subjects were relaxed by apple juice aroma, however no changes in α₁and α₂wave power were observed for the remaining four subjects. It was concluded that apple juice aroma elicits no unpleasant mood. On the other hand, by smelling steamed sweet potato aroma, α wave power was markedly decreased and a sense of tension [was enhanced]. A significant difference between apple juice aroma and steamed sweet potato aroma was observed on the basis of the changes in α wave power. It was clarified that steamed sweet potato aroma is different from apple juice aroma, and is not as pleasant as apple juice aroma.

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Partial seal packaging, which is a new type of modified atmosphere packaging (MAP), was studied to determine its ability to suppress yellowing and softening of Japanese apricot fruit. Five hundred grams of Japanese apricot fruit was placed in an OPS film bag (40μm thick × 150mm × 220mm) and was stored at 20°C. The sealing types used in this experiment were Pattern 1 (4-mm-wide vertically sealed line, 0.4-mm-wide fused part and 0.6-mm-wide nonfused part) and Pattern 2 (3-mm-wide obliquely sealed lane, 7.6-mm-wide fused part, and 2.4-mm-wide nonfused part). In Pattern 2, surface browning of fruit was observed due to insufficient gas permeability of the film. However, in Pattern 1, oxygen and carbon dioxide concentrations remained at about 6 % and 11-18%, respectively, and it was observed that yellowing and softening of the fruit was suppressed. On the other hand, in film packaging with 0.1% perforation, yellowing and softening were observed.

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We propose that half-dried cabbage is a very useful processed form of cabbage, because the appearance of its rehydrated form is almost the same as those of fresh cabbage; moreover, its microbial count showed no increase over a 3-week preservation, its γ-amino butyric acid content tended to increase, and its vitamin C was held constant. To produce half-dried cabbage, shredded cabbage was dehydrated up to 70% its original weight by vacuum drying at 50 hpa at 50°C. The dried cabbage was stored at-2 and 5°C. During 3 weeks of preservation, we analyzed the free amino acid and vitamin C contents of the cabbage once a week. We also measured the total bacterial and coliform counts, as well as the rehydration ratio of the sample immersed in water. The rehydration ratios of the dried cabbage samples preserved at 5 and -2°C decreased by 12.7% and 14.9%, respectively, after 3 weeks. The dried sample stored at -2°C did not freeze even with more than 2 weeks of preservation, and the rehydrated form of this sample hardly differed from fresh cabbage in appearance. Throughout the storage at both 5 and -2°C, the content ratio of glutamic acid to total amino acid decreased and that of γ-amino butyric acid content to total amino acid increased even though total amino acid content showed no change. Total vitamin C content seemed to remain unchanged, and the content ratios of both ascorbic acid and dehydroascorbic acid to vitamin C hardly varied throughout the preservation. The total bacterial and coliform counts of the dried sample hardly changed during preservation at both 5 and -2°C.

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