An increase or decrease in headspace volume of the flexible pouches replaced with oxygen, nitrogen, carbon dioxide and their mixtures were investigated. The changes in volume were associated with the physicochemical properties of gases and packaging materials, the initial gas compositions within the pouches and storage temperature.
Using brown rice as a model system, packaging tests were also conducted against living or oxygen-sensitive foods from the view point of volume changes of the packaging pouch. When oxygen uptake rate of the in-package food became in equilibrium with permeation rate of oxygen which penetnated the packaging materials, in-package nitrogen were eliminated from the pouch because of its higher partial pressure than ambient environment.

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It was previously reported that the brown colour pigment in roast coffee infusion was separated into main three components(A, B, and C)by Sephadex G-25 column chromatography. To clarify the precursors of these brown pigments, the following model roast method was designed. Pack the mixture of 2ml of test solution(pH5.5)and 1.5g of Celite hollowly in a test tube and heat at 190°C for 30 minutes. Add 6ml of water, warm in a boiling bath, cool and centrifuge. Brown pigments in supernatant are separated and estimated by column chromatography. Among many fractions of coffee beans extract separated by solvent extraction, lead acetate precipitation and ion exchange resin chromatography, the fraction containing sugar and chlorogenic acids produced three brown pigments. Sugars gave pigment A and a small amount of B, while chlorogenic acid did not. But when chlorogenic acid coexisted sugars, sugar alcohols, or arabinogalactan of coffee beans gave three pigments. Amino acid and caffein had no effect. In the same way, ether and ethyl acetate extracts from roasted sucrose, and glycerin aldehyde, glycol aldehyde and 5-hydroxymethylfurfrual gave three pigments.
From these results, formation mechanism of these brown pigments in coffee was proposed as follows:

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To evaluate the whipping properties of proteins extracted from yeast of the Candida family grown on n-paraffin, foam stability(leakage)and whippa bility were determined in comparison with those of soybean protein(SP), and the following results were obtained;
1. Foam stability of supernatant obtained by precipitating proteins from alkali extract showed a high level compared with that of extract(E)and protein isolate(P).
2. Leakage and whippability per one mg of protein-N generally decreased with the increase of protein concentration. The levels of whippability of E, P and protein isolate washed with ethanol(PE)were similar with one another, and they were all higher than that of SP in the range below 240mg% of protein-N. Foam stability of PE was remarkably superior to that of the other three samples, especially in the range of low protein concentration.
3. Whipping properties were generally affected with pH. Whippability of E, P and PE were superior, on the other hand foam stability of E and P were inferior respectively to those of SP in the range of pH 4-7. Foam stability of PE showed much higher level than those of the other three samples in an acidic to neutral pH range, and exhibited the level above 95% in the range of pH 3-5.

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An apparatus for measuring the organic acid content was designed and constructed. The apparatus was equipped with constant current unit. The impedance signal measured was converted from analoguetodigital and represented as acid content(%), i.e. as citric acid content for Satsuma mandarin juice, after arithmetrically computed with the corresponding equation. Compensation for the error resulted from the circuit was carried out automatically with the internal standard resistance at every measurement. The error of measurement was within 0.1% as conductance value.
A special temperature correction method was developed by a combination of a standard potassium chloride solution and the temperature coefficient of organic acid. In using the method, the acid content could be determined at the temperature range 5-35°C and the deviation was less than O.04% as citric acid.
The devised correction method was independent of the kind of organic acid, regardless of the variety of pK₁. The correction of the empirical errors, introduced by the measuring cell and contaminants in measuring water, and the check of reading would be simultaneously achieved by the temperature correction.

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Volatile carbonyl compounds in the vapor of cooked rice were analysed be means of the direct gas chromatography. As the result, besides carbonyl compounds which were reported by YASUMATSU et al., iso-buthylaldehyde, n-butylaldehyde and iso-valeraldehyde were newly inferred in the vapor of cooked rice.
Moreover, chromatogram pattern of new rice was compared with that of old rice and difference of both rices was racognized. Carbonyl ccimpounds were generally higher in old rice than in new rice, and n-caproaldehyde increased most remarkably and its increment was in proportion to the stored period.

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