Heat transfer in a pilot scale scraped surface heat exchanger was experimentally investigated, using water and gelatinized wheat flour fluids (solid content 1.8-10.7% (w/w)) as working fluids. Because gelatinized wheat flour fluids had non-NEWTONIAN characteristics, apparent viscosity of the fluids in the scraped surface heat exchanger was determined by use of a generalized form of the power number-REYNOLDS number plot for NEWTONIANS. Scraped side heat transfer coefficient (h_i) increased with increasing rotational speed of a rotary shaft. Mass flow rate (0.03-0.092kg/s) had no definite effects on (h_i). The experimental values of NUSSELT number (Nu) in the range of rotational REYNOLDS number, R_er>2×10³, agreed relatively well with theoretical values by a scraped surface renewal model on the basis of the penetration theory. For R_er<200, the experimental values of Nu were lower than the theoretical ones and the deviation between experimental and theoretical results increased with decreasing R_er.

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To investigate the quality changes during storage, edible amaranth (Amaranthus mangostanus L.), soup celery (Apium graveolens L. var. secalinum Aleff.), malabar spinach (Basella rubra L. var alba Makino), water convolvulus (Ipomoea aquatica Forsk.), chinese flowering cabbage (Brassica parachinensis Bail.) and pak-choi (Brassica chinensis L.) were sealed in 0.03mm polyethylene bags and held at 1, 6, 20 and 30°C, respectively. At 20 and 30°C storage, yellowing of leaves was mainly responsible to quality deterioration, while malabar spinach and pak-choi kept green for relatively long period. Chilling injury was observed in water convolvulus and edible amaranth at 1 and 6°C, and in malabar spinach at 1°C. The injury was manifested as the browning of leaves in the former 2 species, whereas it was as the pitting and softening (loss of turgidity) of leaves in the latter species. Other vegetables were kept good as storage temperature lowered. Decrease of ascorbic acid (ASA) content in edible amaranth, soup celery and pa-choi was retarded with low temperature storage. In malabar spinach and water convolvulus, the ASA content decreased rapidly at low temperatures occuring chilling injury, whereas in edible amaranth the change was retarded at low temperatures. In malabar spinach, the decrease of ASA content was very slow even at 30°C. Decrease of chlorophyll content was retarded at low temperature storage, except soup celery which showed no distinctive change among temperatures. Free amino acid content tended to increase with raising of storage temperature. Total phenol content showed a temporary rise and then decreased in water convolvulus stored at low temperatures. In other vegetables, the level was almost constant.

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Tangxin Pidan, Chinese duck shell egg coagulated with alkali, of which yolk contained soft core, "Tangxin", was ripened for 14 months at 5°C. Permeable matters of albumen and yolk were separated by dialysis against water. After two-week ripening, much water migrated from albumen into extrior of yolk (hard yolk), but not into the soft core (soft yolk). Throughout fourteen-month ripening, inorganic matters in a commercial alkaline solution, penetrated into albumen, diffused gradually into yolk. Changes in some permeable matters showed that chemical decomposition, caused by ripening, proceeded further in albumen than in yolk. In the inner zone of two-week ripened hard yolk, most of yolk spheres were hexagonally shaped and condensed into mass, trapping water among them. While yolk spheres in the soft yolk were disrupted and granules were released. In the outer zone of the hard yolk and all yolk ripened for 14 months, both yolk spheres and granules were disrupted. Yolk spheres in the mass may probably be more stable to alkali than dispersed yolk spheres. Consistency of the hard yolk might be attributable not only to alkaline denaturation of yolk protein but also to formation of the yolk sphere mass. In TEM of albumen any definite pattern was not observed, but sandy matrix was finer than that of heat-coagulated or freezedried fresh duck albumen.

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Dried plain Adzuki Ann granules prepared from Adzuki bean (Vigna angularis) and samples prepared by grinding an aqueous suspension of the dried Adzuki Ann granules by a homogenizer were used as models of intact and ruptured Ann granules respectively. This paper describes a method to determine the proportion of ruptured granules in a standard Ann sample containing intact and ruptured granules in various ratios, by measuring the percentage of starch solubilized by α-amylase. The dried sample (24mg) suspended in a buffer (pH 5.9) was allowed to react with α-amylase (1 unit) at 35°C for 30min. The suspension was then placed in a boiling water bath for 10min, cooled and centrifuged, and the amount of starch solubilized was measured. The amount of starch solubilized by the treatment with HCl (0.25N) instead of α-amylase was regarded as the total amount of starch in the sample. The percentage of starch solubilized by the α-amylase treatment was defined as the ratio of the amount of starch solubilized by the α-amylase treatment to that by the HCl treatment. It was found that the percentage of starch solubilized by the α-amylase treatment was about 2% for the intact granules and about 98% for the ruptured granules and increased linearly with a increasing proportion of ruptured granules in the standard Ann sample. The results suggest that the percentage of starch solubilized by the α-amylase treatment might be applied to the determination of ruptured and damaged granules in Ann samples.

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Effects of direct ethanol addition to raw ingredients on the preservation of semi-dried Japanese noodle and conditions for increasing the ethanol retention after drying were studied. (1) Ethanol in Japanese noodle was evaporated rapidly almost immediately after drying, however, the rate of ethanol evaporation was soon slowed down when moisture content came close to 30% of Udon. (2) Increase of viable cell counts was observed in ethanol non-added control samples of over 17-18% moisture content, however, the samples added 3-5% of ethanol did not show any increase at higher moisture content by 2-4%. (3) The effect of ethanol addition on the preservation of semi-dried Japanese noodle was ascribed to not only the lowering of water activity (Aw) of the sample, but also to the bacteriostatic and fungistatic effects of ethanol under lower Aw conditions. (4) Ethanol content of semi-dried Japanese noodle was successfully maintained at relatively high level under the drying condition of low temperature (20°C) and humidity (65% R.H.). (5) Retention of ethanol in semi-dried Japanese noodle was successfully improved by addition of sucrose or dextrin. On the other hand, the lowering of sodium chloride content of semi-dried Japanese noodle enhanced this effect.

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The general composition, inorganic cations, free amino acids and organic acids were examined on 11 kinds of special vinegars in Japan, which are commercially available at relatively high prices. The data obtained were compared to those of ordinary rice vinegars. The results were as follows: (1) Not much difference in general composition was detected among these vinegars, though sediments were found in most samples of black vinegars which emphasized addition of caramel during its preparation. (2) The major inorganic cations present in special vinegars were found to be Na followed by K and Mg. (3) The total free amino acid contents of special vinegars ranged from 56.9 to 362.6mg/100ml were rich in alanine, leucine, lysine, valine and glycine. The special vinegars were high in amino acid components as compared to the ordinary rice vinegars. The difference in their amount seemed to be caused by the difference in the raw materials and method of preparation. The ratio of essential amino acids to the total free amino acids ranged from 45 to 50%. (4) Lactic acid was the most abundant followed by pyroglutamic acid among organic acids except acetic acid in special vinegars. The results of this study showed that special vinegars which are sold at relatively high prices were doubtful in terms of quality and prices.

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It is reported that freshness of fish meat can be expressed by the K value according to the following calculation: K value (%)=(HxR+Hx)×100/(ATP+ADP+AMP+IMP+HxR+Hx). A freshness analyser, a kind of biosensor, was recently manufactured by the Oriental Electric Co., Niiza-shi. We examined the availability of this sensor and confirmed that the K value was obtained with a sufficient accuracy for practical application, within several minutes. Using this sensor, we determined the K values of fishes being put in the market. The samples used were horse mackerel (Trachurus japonicus), sardine (Sardinia melanosticta), saury pike (Cololabis saira) and pacific herring (Clupea pallasi) purchased from a departmentstore (A), supermarkets (B, C, D) and private retail stores (E, F). The K values of the samples increased up to 50% within several hours at 13-16°C and within 4 days at 3-5°C, respectively, but not at -20°C. The K values of the samples were diversed at every fish, every store, and every date of purchasing. It looks very hard to find the type of store where we can get the best goods. If the freshness of fishes were indicated by the K value labelled on package, it would be very convenient for the customers in choosing the fresh goods at store.

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A method is described for the determination of ethylenediaminetetra-acetic acid (EDTA) and its metal chelates in foods. The principle of the method is that free copper ion (Cu²⁺) reacts with bathocuproine but EDTA-Cu does not under definite condition. Food samples were homogenized with 0.1M NaOH, then subjected to equilibrium dialysis against 0.02M NaOH. EDTA and its metal chelates in the dialyzate were converted into EDTA-Cu at pH 2.5 by the addition of CuSO₄. This solution was then divided into two portions of equal volume. One portion was subjected to assay of free Cu²⁺, and the other to assay of total (the sum of free and chelated) Cu²⁺. EDTA was calculated from the difference between the absorbances (477nm) obtained with free and total Cu²⁺. Analyses of several foods with EDTA-Ca added showed the recovery of 88.7-99.4% for 50μg/g and 92.7-99.9% for 250μg/g. Food ingredients such as organic acids, proteins, amino acids, peptides, phenolic compounds and emulsifying agents were without interferences.

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A close correlation was demonstrated between the pungency of fresh cabbage evaluated by sensory tests and the concentration of allyl isothiocyanate (AITC) formed in macerated cabbage with 39 cultivars commonly grown in Japan. Most of the cultivars tested contained AITC lower than 0.5mg/100g, and had no pungency. Only 3 cultivars containing AITC higher than 2.0mg/100g showed a pungency. It was concluded that there is virtually no problem as far as the pungency is concerned, when cabbages grown in Japan are consumed raw.

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The relationship of natural flesh darkening to polyphenoloxidase (PPO) activity was investigated in several Japanese persimmon cultivars that had different intensities of flesh darkening during their fruit development. Flesh darkening in the fruits was found to be closely associated with PPO activity. That is, the initiation of flesh darkening was observed when PPO activity began to increase in the cultivars that had darkened flesh; however, no increase in PPO activity was seen in the cultivars that had non-darkened flesh. Ethanol treatment on the tree to intact pollination-variant type fruits when they were immature and still astringent somewhat accelarated both the increase in PPO activity and the initiation of flesh darkening. These results indicate that natural flesh darkening in Japanese persimmon fruits is partly due to the increase in PPO activity in the flesh, and ethanol treatment on the tree induces the early increase in PPO activity, which in turn initiates the flesh darkening.

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