Treament of "maceration" in cider-making appreciably reduces the amount of malate in apple juice and cider. Apple fruit malic enzme is likely to be one of the enzymes which play the most principal role in the reduction of acidity. To obtain the best conditions to reduce acidity, malic enzyme was extracted and purified from mesocarp tissue of ripe apple fruits of Delicious variety by DEAE-cellulose column chromatography and preparative polyacrylamide-gel electrophoresis. The purified enzyme appeared to be almost (but not completely) homogeneous as evaluated by polyacrylamide-gel electrophoresis.
The optimum pH for the enzyme reaction was, in the presence of Mn⁺⁺, 6.2-6.6 at a low level of L-maiate (3×10^-8M), while 7.6 at a high level of L-maiate (5×10^-2M, a normally occurring concentration in apple juice). Activity of the purified enzyme was most stable at pH 5.0 and the stability declined on either side of this pH value. Treatment with tannic acid lowered the enzyme activity to 50-60% of the initial activity. The enzyme was strongly inhibited by Hg⁺⁺, while inhibition by Cu⁺⁺ was far more slight.

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In the previous paper the authors reported the functional properties of Yuba-film made from soybean 11S and 7S globulins. The present work aims at elucidation of the effects of lipid to the properties of Yuba-film prepared from the respective proteins.
The protein solutions homogenized with soybean oil were used to prepare the Yuba-film, and physical properties of the formed films investigated, and extractability of lipid by solvents from the films was also examined to reveal the lipid distribution in the films.
The films containing lipid were generally stronger and more extensible than the protein film, and the 11S film was more significant in these properties in comparison with the 7S film. The lipid contained in the 7S film was largely extracted with ether and chloroform-methanol mixture, but only partial lipid was extracted from the 11S film. From the result it might be thought that 11S was more lipophile than 7S.

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As a part of study on the changes in quality of honey by heating, the changes of content, acidity, color and antibacterial activity were investigated.
1) With increasing temperature and time of heating. the content ratio of fructose to glucose and that of sucrose to sum of fructose and glucose declined, but, on the contrary, the ratio of lactone acidity to free acidity increased.
2) When honey was heated, the amount of hydroxymethylfurfural (HMF) increased and color darkened by browning reaction. It was observed that, in the browning reaction under acidic medium like honey, fructose reacted more rapidly than glucose, and under this condition the reaction proceeded through HMF in spite of absence of amino acids. But the reaction was difficult to proceed in the system wherein HMF was the starting material.
3) Hydrogen peroxide which gives major antibacterial activity against Staphylococcus aureus in honey was produced from glucose through the action of glucose oxidase. The loss of the antibacterial activity of honey by heating was considered to attribute to absence of the peroxide due to inactivation of glucose oxidase by heating.

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A proteoliplid has been isolated from the chlorofolm: methanol (2:1) extract of defatted soybeans by the procedure of fluff formation after dialysis against chlorofolm: methanol (2:1) and water. The proteolipid gave a yield of 0.04% of the defatted soybean and showed a single spot on a thin-layer chromatogram of silica gel. The content ratio of protein (N×5.7) and lipid was nearly 2:1.

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The antioxidant action on linoleic acid of four types of caramels which were prepared by different methods (A from glucose, sodium hydroxide and ammonium sulfite; B from glucose and ammonium hydroxide; C from glucose, sodium sulfite and ammonium sulfite; D from sucrose) was investigated. The results obtained are as follows.
1. Caramel B showed the highest antioxdative activity under the various conditions. The relative activities compared with those of BHA were as follows: ca. 1/11 for caramel B, ca. 1/100 for caramel A and C, ca. 1/500 for caramel D.
2. Comparison of the antioxidative activity of dialyzed caramel with that of undialyzed one showed that the latter exhibited higher activity than the former in any type of caramel.
3. By the investigation on the relationship between the antioxidative activity and color intensity, nitrogen content, or reducing power of caramel, it was indicated that, generally, the higher color intensity or nitrogen content, the higher antioxidative activity. But a definite relation was not found between the antioxidative activity and the reducing power.

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Emulsifying capacity of egg yolk was determined by the following method:
1. First, 20g of fresh egg yolk and 24ml of salt-acetic acid solution were put in the 3 quart bowl of Hobert Mixer Model C-100-T. The contents in the bowl were mixed by the wire "D" whip continuously, and refined soybean oil was added in the bowl until the emulsion was formed and collapsed.
2. The visual end point was adopted the changing point from "Oil in Water" to "Water in Oil" at the time of the emulsion was collapsed. Emulsifying capacity of egg yolk was showd as weight of added soybean oil at the end point under various concentration of salt and acetic acid in continuous water phase.
The result were:
1. If the concentration of salt and acetic acid in continuous water phase was more than 10% as sodium chloride and 4% as acetic acid, yolk in the bowl was gelled and the emulsion became ununiform and unstable one.
2. When their concentration was less than 10% as sodium chloride and 4% as acetic acid respectively, smooth emulsion was formed, but the result was showed that the lower concentration, the higher emulsifying capacity became.
3. And, if the continuous water phase was included salt and acetic acid in the same time, the emulsifying capacity of egg yolk was downed by multiplication effect of salt and acetic acid.

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The commercially available flavoring substances such as beef extract, yeast extract and hydrolyzed vegetable protein, were fractionated into seven fractions (1-VII) by column chromatography on Sephadex G-25 and Amberlite XAD-2, thereafter, the relationship between components and flavors was studied.
Fraction I containing mainly peptides with high molecular weight gave colloidal feeling in organoleptical test, and produced weak meat-like aroma by heating.
Fraction III containing peptides. with low molecular weight and Maillard reaction products gave beef-like flavor and it was elucidated that this fraction was the most important fraction in beef extract.
Fraction IV containing mainly free amino acids was the main component of hydrolyzed vegetable protein, but not so of beef extract. The flavor of fraction IV of yeast extract gave yeasty and brothy feelings, and this fraction could be separated into two fractions giving brothy taste and yeasty odor by column chromatogrphy on Amberlite XAD-2.

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Mayonnaise sauce is required the emnulsion stability, paticularly the prevention of separation of oils for transportion from manufacturer to retailer. Several methods were compared for evaluation of stability of mayonnaise against transport vibration.
The results indicated that vertical vibration (amplitude 15mm, 500c.p.m., 60min.)and followed centrifugation (140G, 30min.) using polyethylene bottle could be adopted as index of the stability of mayonnainse.

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Evaluation of by-products of citrus processing industries as culture media was investigated employing Pleurotus ostreatus as an edible mushroom.
Dried peel of Citrus Unshu gave satisfactry results when used with small amount of rice bran and calcium carbonate with comparison of saw dust of broad leaf tree.

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