Kana Ioku

In our earlier studies, 445 Japanese texture terms were collected from questionnaires administered to food scientists/technologists and interviews with texture researchers. In the present study, foods associated with the 445 Japanese texture terms were collected and analyzed. Terms that have the same meaning but are represented by different Chinese characters and onomatopoeic words that are derived from the same sound were classified into same term groups. A total of 271 term groups were formed in the study. Eighteen trained descriptive panelists were asked to write down food items associated with each term group. As a result, a comprehensive pool of 935 kinds of food associated with the texture terms was developed, and the data was submitted for correspondence analysis to understand the structure of Japanese texture vocabulary. The dimension 1 contrasts fracture versus fluidity terms. The dimension 2 can be interpreted as the axis related to flufflness and airiness. The data obtained in this study can be applied to preliminary lexicon sources of descriptive sensory evaluation and can provide useful clues to the international understanding of Japanese texture terms.

In our earlier studies, 445 Japanese texture terms were collected from questionnaires administered to food scientists/technologists and interviews with texture researchers. In the present study, foods associated with the 445 Japanese texture terms were collected and analyzed. Terms that have the same meaning but are represented by different Chinese characters and onomatopoeic words that are derived from the same sound were classified into same term groups. A total of 271 term groups were formed in the study. Eighteen trained descriptive panelists were asked to write clown food items associated with each term group. As a result, a comprehensive pool of 935 kinds of food associated with the texture terms was developed, and the data was submitted for correspondence analysis to understand the structure of Japanese texture vocabulary. The dimension 1 contrasts fracture versus fluidity terms. The dimension 2 can be interpreted as the axis related to fluffiness and airiness. The data obtained in this study can be applied to preliminary lexicon sources of descriptive sensory evaluation and can provide useful clues to the international understanding of Japanese texture terms.

The present study investigated the vocabulary for food texture of Japanese consumers through questionnaires in metropolitan area and Kyoto-Osaka-Kobe area. Four hundred and forty five terms collected through questionnaires and interviews to texture researchers in our previous study were judged whether each term was used by consumers or not. In each questionnaire about 200 terms were listed because 445 terms were too many to judge by one subject. Four hundred and forty five terms were divided into 4 groups and two of them were selected at any combination so that combinatorial effect and order effect were reduced. Three thousand five hundred and thirty three subjects judged whether each term was used to describe food properties or not. Out of the 2 582 collected questionnaires, 2 437 were completed and thus used for further analysis. The criterion of the percentage of judgments as food expressions was 75% or greater and 135 terms met this criterion with a confidence level of 95%. The terms judged as food expressions at 90% or greater were 66 terms with a confidence level of 95% such as "katai (hard)", "creamy", "saku-saku (crispy)", "pari-pari (crispy)" and "neba-neba (sticky)". They were considered to be the core terms of texture vocabulary of Japanese consumers.

The present study investigated the vocabulary for food texture of Japanese consumers through questionnaires in metropolitan area and Kyoto-Osaka-Kobe area. Four hundred and forty five terms collected through questionnaires and interviews to texture researchers in our previous study were judged whether each term was used by consumers or not. In each questionnaire about 200 terms were listed because 445 terms were too many to judge by one subject. Four hundred and forty five terms were divided into 4 groups and two of them were selected at any combination so that combinatorial effect and order effect were reduced. Three thousand five hundred and thirty three subjects judged whether each term was used to describe food properties or not. Out of the 2 582 collected questionnaires, 2 437 were completed and thus used for further analysis. The criterion of the percentage of judgments as food expressions was 75% or greater and 135 terms met this criterion with a confidence level of 95%. The terms judged as food expressions at 90% or greater were 66 terms with a confidence level of 95% such as "katai (hard)", "creamy", "saku-saku (crispy)", "pari-pari (crispy)" and "neba-neba (sticky)". They were considered to be the core terms of texture vocabulary of Japanese consumers.

The flavonoid contents in the vegetables have the possibility to vary according to seasons. The flavonoid contents about 15 kinds of vegetables circulated in June were examined by HPLC after hydrolysis. In addition, the amounts of quercetin and luteolin in the green pepper during the year were studied with the main production area Miyazaki and Kochi. The content of quercetin in green pepper, was 3.15 ± 1.77 mg (aggregate average) and luteolin content was 8.15 ± 4.10 mg per 100 g of fresh weight. Flavonoid contents were increased in October to December, and the tendency to decrease in May to June. The relations with the amount of the ultraviolet rays irradiation was suggested. Moreover, a significant difference was observed among homes at time when a lot of contents were different. The contents of quercetin in June and in January in vegetables (kale, komatsuna, spinach, chin-gen-sai, and perilla) were not different significantly except for kale. Therefore, it was concluded that the changes of the amount of flavonoid in the vegetables were two ways, one of which was few changes and the other showed the maximum content in autumn during year.

Texture descriptive terms in Japanese were collected and validated. Five hundred and ninety-nine words were obtained from an open-ended questionnaire distributed to 116 food specialists in Sendai, northern area (25 individuals), Tokyo, central area (29), Osaka, western area (32) and Kagoshima, southern area (30). Out of these 599 words 332 terms were selected in a 2-day roundtable discussion made by 4 researchers. To the 332 terms added were 94 terms that have been collected from dictionaries, technical books on food texture and research papers about food texture. Thus, a list of 426 terms was presented to 55 selected assessors who had some experience of research on texture. They were asked whether these terms correctly expressed food texture. Then the data were evaluated by 4 experts who had been engaged in research on food texture or rheology for a long time. As a result of deletion and addition, 445 terms were obtained as a texture descriptive language. About 70% of the terms are onomatopoeic words. This shows onomatopoeic words play an important role in texture description in Japanese. Compared with the data taken from questionnaires in 1968, some new onomatopoeic words such as "mochi-mochi" and "puru-puru" are included in the list.

The flavonoid contents in the vegetables have the possibility to vary according to seasons. The flavonoid contents about 15 kinds of vegetables circulated in June were examined by HPLC after hydrolysis. In addition, the amounts of quercetin and luteolin in the green pepper during the year were studied with the main production area; Miyazaki and Kochi. The content of quercetin in green pepper, was 3.15 +/- 1.77mg (aggregate average) and luteolin content was 8.15 +/- 4.10mg per 100g of fresh weight. Flavonoid contents were increased in October to December, and the tendency to decrease in May to June. The relations with the amount of the ultraviolet rays irradiation was suggested. Moreover, a significant difference was observed among homes at time when a lot of contents were different. The contents of quercetin in June and in January in vegetables (kale, komatsuna, spinach, chin-gen-sai, and perilla) were not different significantly except for kale. Therefore, it was concluded that the changes of the amount of flavonoid in the vegetables were two ways, one of which was few changes and the other showed the maximum content in autumn during year.

Onion is a major source of flavonoids and is cooked in various ways in the world. The major flavonoids in onion are two quercetin glycosides, quercetin 4'-O-beta -glucoside (Q4'G) and quercetin 3,4'-O-beta -diglucosides (Q3,4'G), which are recognized as bioactive substances that are good for our health. We have investigated the effect of cooking procedures on the content of antioxidants. We selected quercetin conjugates, total phenol compounds, and ascorbic acid to estimate the amount of flavonoid ingestion from onion. We examined the following cooking methods: boiling, frying with oil and butter, and microwave cooking. Various cooking methods do not consider the degradation of quercetin conjugates when cooking onion. Microwave cooking without water better retains flavonoids and ascorbic acid. Frying does not affect flavonoid intake. The boiling of onion leads to about 30% loss of quercetin glycosides, which transfers to the boiling water, At that time, the effect of additives on the quercetin conjugates is different according to the compounds, The hydrolysis of quercetin glycosides for daily cooking might occur with the addition of seasonings such as glutamic acid. Additional ferrous ions accelerated the loss of flavonoids.

Onion is a major source of flavonoids and is cooked in various ways in the world. The major flavonoids in onion are two quercetin glycosides, quercetin 4'-O-beta -glucoside (Q4'G) and quercetin 3,4'-O-beta -diglucosides (Q3,4'G), which are recognized as bioactive substances that are good for our health. We have investigated the effect of cooking procedures on the content of antioxidants. We selected quercetin conjugates, total phenol compounds, and ascorbic acid to estimate the amount of flavonoid ingestion from onion. We examined the following cooking methods: boiling, frying with oil and butter, and microwave cooking. Various cooking methods do not consider the degradation of quercetin conjugates when cooking onion. Microwave cooking without water better retains flavonoids and ascorbic acid. Frying does not affect flavonoid intake. The boiling of onion leads to about 30% loss of quercetin glycosides, which transfers to the boiling water, At that time, the effect of additives on the quercetin conjugates is different according to the compounds, The hydrolysis of quercetin glycosides for daily cooking might occur with the addition of seasonings such as glutamic acid. Additional ferrous ions accelerated the loss of flavonoids.

Recently, much attention has been directed to problems of the environmental pollution. The present investigation was attempted to obtain a basic information about a possibility of the replacement of aluminium laminate film to plastic film which was more easy disposal treatment. Then, the effects on the stability of packed ground sesame seeds under ultraviolet light (UV) exposure (wavelength; 365nm), were compared among several packaging materials of different oxygen permeabilities and different 365nm UV absorbances. Against the oxidation of the sesame seed's oil, the plastic films cutting 365nm UV had a little protective function and the aluminium laminate film had the best one. On the protection of the roasted sesame aroma, the aluminium laminate film had also the best effect and the plastic films cutting 365nm UV had slightly the one. The plastic film with the permeability of 365nm UV brought the oxidative deterioration of the aroma. Volatile compounds growing from the clear plastic films under UV exposure, weaken the sesame aroma. So, the aluminium laminate film was the best packaging material.

The antioxidative effect of quercetin, quercetin 3-O-beta-D-glucopyranoside (Q3G), quercetin 4'-O-beta-D-glucopyranoside (Q4'G) and quercetin 7-O-beta-D-glucopyranoside (Q7G) was examined in solution and liposomal phospholipid suspension. First, their peroxyl radical-scavenging activities were investigated by measuring the inhibition of hydroperoxidation of methyl linoleate initiated by a radical initiator, 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN). Quercetin exhibited the highest peroxyl radical-scavenging activity judging from the rate of hydroperoxidation during the induction period (R(inh)) and the length of induction period (t(inh)). Although Q7G showed an induction period, its R(inh) was higher and its t(inh) was lower than that of quercetin. Neither Q3G nor Q4'G gave a clear induction period in the curve of hydroperoxide formation. The rate of hydroperoxidation in the presence of Q3G was higher than R(inh) of quercetin and the oxidative loss of Q3G was much slower than quercetin or Q7G when exposed to AMVN in solution. Q4'G exerted little inhibition compared to Q3G or Q7G. Next, the antioxidative activity of quercetin and its monoglucosides in phospholipid bilayers was examined by measuring the inhibition of lipid peroxidation in large unilamellar vesicles composed of egg yolk phosphatidylcholine (PC) and a water-soluble radical initiator. They retarded the accumulation of PC-hydroperoxides and the induction period increased in the order of Q4'G < Q3G similar to Q7G < quercetin. It is therefore concluded that quercetin acts as an antioxidant more efficiently than its monoglucosides when phospholipid bilayers are exposed to aqueous oxygen radicals.

The effects of rat bile-pancreatic juice (BPJ) on Fe2+ induced oxidation of soybean phosphatidylcholine (PC) was monitored to investigate the influence of this digestive juice on oxidative damage in the gastrointestinal tract. A large volume of BPJ (50% in the suspension of PC, v/v) suppressed the lipid peroxidation, but a smaller volume had the reverse effect. BPJ could decompose free fatty acid hydroperoxides (FFA-OOH) at a lower concentration (similar to 0.2 mM) completely, although its phospholipase activity liberated FFA-OOH from PC hydroperoxides. Sodium deoxycholate enhanced the Fe2+ induced oxidation of PC in a concentration-dependent manner when PC was suspended in the huller. Boiled BPJ suppressed Fe2+ induced and peroxyl radical initiated oxidation of sodium deoxycholate micelles of soybean PC up to similar to 50% (v/v). It was strongly suggested that rat BPJ had a biphasic effect on Fe2+ induced oxidation of phospholipids depending on the enhancement by bile salts and the inhibition by antioxidant components with radical-scavenging activity and hydroperoxide-decomposing activity.