The denaturation of rabbit skeletal myofibrils caused by freezing and thawing was measured by the change of Ca²⁺-ATPase activity. The changes in activity were high at concentrations of myofibrils less than 0.2mg/ml. The rate of denaturation was increased by the repetition of freezing and thawing, or by prolonged freezing time. The denaturation caused by freezing and thawing was protected in the presence of non-ionic surfactants such as Tween 20. The addition of 0.3 % Tween 20 was effective for the protection against denaturation. The effective concentration for non-ionic surfactants were lower than for sugars. The addition of Tween 20 and glycerol showed a synergistic effect for the protection of freezing-thawing denaturation.

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This paper describes the possibility of transport in cream cheese by way of a dry container truck in summertime using an adiabatic container, refrigerant and an adiabatic sheet. The adiabatic container consists of a small scale collapsible box and shows 3. 7 to 5. 6 times the overall coefficient of heat transfer in comparison with that of the large one. The experimental results are shown that the freezing point and the latent heat of melting for the refrigerant are almost the same values as the pure water, respectively. It is difficult to keep the cream cheese temperature under 8°C (The initial temperature is 0°C) after keeping 24 hrs only using the adiabatic container, however, it can be controlled within the 8°C by changing the outer package (from a corrugated fiberbord box to a foam polystyrene box) and using the adiabatic container with the refrigerant and the adiabatic sheet. The experimental results confirm that it can be controlled to the desirable temperature for the cream cheese using an efficient container, outer package, refrigerant and sheet in the adiabatic properties.

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The content of chemical constituents in small mume fruit (Japanese Apricot, Prunus mume Sieb. et Zucc. var. microcarpa Makino, cv. Ryukyo koume and cv. Koshu koume) was determined in relation to growth and maturation in investigations conducted between May 11th to June 22 nd 1981. The following results were obtained. 1) The growth curve of the fruit showed a double sigmoidal pattern like that of stone fruits, the three growth phases were designated into periods rapid growth stage, stagnation stage and rapid enlargement stage. 2) The fruit reached a maximum hardness of 1011±113g/φ in the fruit stagnation stage and decreased about 1/3 of maximum hardness in relation to fruit enlargement. 3) The AIS content of the fruit was 4.65% in the immature stage, and the initial content decreased about 1/2 during growth and maturation. The ratio of total pectin to AIS increased from 16.9% to 29.7% during growth and maturation. 4) An increase was observed in ash, total nitrogen and free amino acid content during the growth of the fruit and a corresponding decrease with its enlargement. 5) The titratable acidity content of the fruit was in the region of 3.1 to 5.5g/100 g. It was observed to increase in the fruit stagnation stage reaching a constant in the fruit enlargement stage. The results were similar to the changes in the soluble solids content. 6) The fruit contained malic, citric, oxalic and succinic acids. The content was in the region of 3478 to 6517mg/100g during growth and maturation. The changes showed similarity to those of titratable acidity content. A significant increase was observed from 8% to 60% in citric acid content during growth and maturation and the malic acid content increased in the stagnation stage, then decreased from 86% to 39% in the fruit enlargement stage. A marked decline was noticed in the ratio of malic acid to citric acid from 10.59 to 0.65 during growth and maturation. 7) The total amount of free amino acid in the fruit increased to a maximum of 340mg/100g with its growth, then the maximum content was observed to decrease about 1/2 in the fruit enlargement stage and increase as it became over-ripe. In all stages of growth and maturation, between 73% to 87% of the total free amino acid in the fruit flesh was occupied by asparagine and when 7-amino butyric acid, glutamic acid, glutamine and aspartic acid were added, this totalled between 93% to 98%. 8) Significant changes in the content of the fruit sugars, sucrose, glucose, fructose and sorbitol were observed in fruit growth and maturation. The composition of major sugar was between 36% to 54% glucose in the immature stage, glucose and sorbitol between 22% to 31% in the stagnation stage, between 33% to 34% sucrose and between 49% to 78% in the enlargement and over ripe satages. Also a decrease was observed in glucose content and the fructose content decreased after an increase, also a decline was noticed in the ratio of glucose to fructose from 4.94 to 0.55 during growth and maturation. 9) The mineral content reached its maximum of 3123 ppm in the fruit stagnation stage, and the maximum content decreased about 78% in the fruit enlargement stage. Between 90% to 95% of the mineral content of the fruit flesh was occupied by K, increasing to 99% with the addition of Ca and Mg.

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Investigations were conducted into the effect of manufacturing conditions on the hardness of salted small mume fruit which had been cured by the brine salting method. A comparison was made of the pectic substances and Ca content with the hardness of the fruit. The following results were obtained. 1) The yield rate of salted small mume fruit produced by the brine salting method was 10% higher than that produced by the dry salting method. 2) The content of Ca bound to pectic substances in salted small mume fruit was in the order PSP (hexametaphosphate-soluble pectin) > HSP (hydrochloric acid-soluble pectin) > WSP (water-soluble pectin). 3) As the Ca content (mg/g in PSP) increased, the translation from PSP to HSP and an increase in hardness were observed. 4) Salted small mume fruit containing Ca compounds were observed to maintain their hardness significantly longer than those with Mg compounds and, in the case of Ca compounds, salted mume fruit containing weak electrolytic Ca compounds were observed to maintain their hardness longer than those with strong electrolytic Ca compounds. 5) The Ca content (mg/g in PSP and WSP) was noticed to increase with the addition of Ca compounds, and a decrease in PSP and WSP and an increase in HSP and hardness were observed

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The content of chemical constituents in mume fruit (Japanese Apricot, Prunus mume Sieb. et Zucc.) was determined in relation to ten varieties. The following results were obtained. 1) The weight of the fruit varied from between 2.6 and 3.6g (small size), 15.0 to 34.3g (middle size) and 65.4g (large size). 2) The percentage of the total weight of the fruit occupied by the pit was observed to be in the order of small size > middle size > large size. 3) The total nitrogen, free amino acid and ash content of the small size fruit were greater than the middle size and large ones, but the titratable acidity content was reduced with an increase in size. 4) The small size fruit contained more alcohol-insoluble solid and total pectin than the middle size ones. 5) Malic and citric acids were found to be the major organic acids in mume fruit. A ratio of 1. 51 : 3. 32 of malic acid to citric acid was observed, revealing a higher content of malic acid. 6) The free amino acid and ammomia (except 'Ryukyo koume') content of the small size fruit (276-758 and 67.2-84.8mg/100g) were significantly greater than the middle size and large ones (87-180 and 0.3-2.2mg/100g). 7) The sugar component varied widely according to the variety of mume fruit. In the small and middle sizes, sorbitol and sucrose was the predominant sugar, but no significant change was observed in the large size fruit.

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