The freshness-preserving effects of contact dehydration sheets (CDS) on Pacific cod and Japanese red bream were verified by three methods for freshness assessments: K value, volatile basic nitrogen (VBN), and viable cell counts. The amount of drips and moisture content of the two fishes samples wrapped in CDS were measured and compared with those wrapped in poly (vinylidene chloride) film as a control. The results of the drip loss and moisture content indicate that CDS appeared capable of absorbing the majority of the excess moisture. Distinct freshness-preserving effects, based on the K value and VBN, were apparent from using CDS for Pacific cod. Since cod flesh has a high water content, this fish becomes tainted very easily. No significant differences in viable cell count between the two wrapping treatments throughout the storage period for either fish was apparent.

View full abstract

A histological comparison of heated and unheated surimi (minced fish meat) was made to evaluate the distinction.
Sasakamaboko (broiled surimi) and raw surimi were used in this study. The materials were fixed in 10% formalin solution, embedded in paraffin, and cut by a microtome. Sections were stained with two acid dyes, which were selected and paired from seven acid dyes on the basis of differences in molecular weight and color. Each pair of dyes was dissolved in a citrate-phosphate buffer solution and adjusted to pH 2.2.
The inside of the sasakamaboko differed from the raw surimi in its stainability. The sasakamaboko differentiated clearly from raw surimi by staining with the dye pair of picric acid with Direct blue 1and Sirius red F 3 B. The inside of heated surimi was stained by picric acid with Tartrazin and Naphtol green B, whereas raw surimi was stained with Sirius red F 3 B and Direct blue 1.

View full abstract

In order to clarify the mechanism for the sol-gel transition of a gelatin solution by adding sugar and alcohol, we measured the viscosity by a non-destructive method, as well as the optical rotation, dynamic viscoelasticity and rupture characteristics.
The starting time for gelation was reduced, the gelation time was extended and the gelation temperature was increased by adding sugar. On the other hand, the starting time for gelation and the gelation time were extended, and the gelation temperature was reduced by adding alcohol.
Changes during sol-to-gel transition occurred in the following order: increasesd dynamic viscosity, dynamic elasticity, and then optical rotation.
The specific rotation of the gelatin solution was highest in the presence of sorbitol. It seems that helices were formed more easily. As cooling progressed, both the dynamic elasticity and dynamic viscosity of gelatin with sorbitol increased the most.

View full abstract

The effects of sucrose on the rheological properties of corn starch paste was studied by static and dynamic viscoelasticity measurements, DSC measurements and microscopic observation. The sucrose concentration was varied between 0% and 55% by weight. The viscosity of the paste increased with increasing sucrose concentration up to 20 wt% and then decreased with increasing sucrose concentration above 20 wt%, although the viscosity of the samples containing sucrose was higher than that of the control at higher shear rate; i. e., the shear thinning behavior became less pronounced. A lower content of sucrose enhanced the swelling of starch granules, while a higher content of sucrose decreased the rate of swelling and resulted in a higher gelatinization temperature to higher temperature. No effect on the viscoelasticity of corn starch paste containing more than 20 wt% sucrose was apparent when the sucrose was added after gelatinization. The viscoelasticity of corn starch paste to which sucrose had been added after gelatinization increased with increasing sucrose concentration.

View full abstract

An investigation was made to examine effects of pickling in various proportions of lemon juice and rice vinegar on the hardness and taste of pickled fish.
Commercially available lemon juice and vinegar were used.
The fish samples were treated with 5% salt, kept in a refrigerator for 20 hours, and then pickled for 5 hours in various mixtures of lemon juice and vinegar. It was found that the lemon juice in the mixture softened the fish meat. Increasing the proportion of lemon juice in the mixture accelerated, the penetration of the solution into the fish meat and thus increased the softening effect.
A sensory evaluation showed that a ratio of vinegar to lemon juice of 8: 2 resulted in the best, umami (flavor-enhancement) taste with 5% statistical significance.

View full abstract

A questionnaire survey was conducted of young adults aged from 18 to 29 on buying and discarding food materials to investigate their attitudes and awareness to wasting food.
Males living alone tended not-to buy fresh vegetables and fish and prepare their own evening meals. They instead bought highly processed foods, and discarded old vegetables and packaged food without separating the contents from the packaging more often than females. Females living alone bought fresh vegetables and fish in smaller amounts and prepared their evening meals, although they discarded old vegetables more often than females living with the family. However, such females living alone prepared evening meals more frequently tended to discard old vegetables less than others from a cross tabulation analysis. The females made more use of old vegetables had a more appropriate attitude to discarding some foods after the use-by date, and had greater awareness about the disposal of leftover food and small packed foods, and about the use-by date.

View full abstract

Pan-frying with diacylglycerol-rich cooking oil (DG oil) was carried out to assess the influence of thermal cooking on the oxidative stability of DG oil in comparison with that of triacylglycerol-rich cooking oil (TG oil). The DG oil was spread over the surface of an aluminum pan coated with stainless steel, which was heated for a specified time with an IH electric heater. The color difference (ΔE value)of the DG oil after 120 seconds of heating at a temperature of more than 200°C was greater than that of the TG oil. The p-anisidin and carbonyl values, which were used as oxidative indices of the DG and TG oils, were not changed at a temperate of less than 200°C, but these values increased in proportion to the heating time at ahove 200°C. The acid value of the DG and TG oils did not change above or below 20O°C, while the peroxide value of both oils increased in proportion to the heating time below 200°C. The amounts of polyunsaturated fatty acids (C18: 2 and C18: 3) decreased markedly after 120 seconds of heating at above 200°C. These results indicate that the thermal oxidation of DG oil during pan-frying was basically the same as that of TG oil, and that both oils seemed to be stable during short-term heating at temperatures less than 200°C.

View full abstract

“Nimono” dishes of vegetables boiled in seasoned soup are, said to be one of the most difficult to cook because of the tendency to cause boil-collapse. With the purpose of establishing a method to prevent boil-collapse in “nimono” during quantity cooking, we chose potato as the material, used different pre-cooking methods, and compared the amount of boil-collapse. The four methods of precooking used were steaming, deep frying, stir frying, and boiling. The degree of potato boil-collapse was measured by an overall analysis of the amount of collapsed potato in the seasoned soup, the color difference, the value of breaking strength, the state of the tissues in the potatoes that did not collapse, and the rating by sensory evaluation. The results indicate, that deep frying was the most effective precooking method to prevent the boil-collapse of potatoes in “nimono. ”

View full abstract

The characteristics of diacylglycerol-rich oil (DAG) were examined by comparing the use of DAG with triacylglycerol-rich oil (TAG) as a control for preparing sauté vegetables and French dressing and mayonnaise.
The DAG and TAG samples were prepared to give a fatty acid composition and tocopherol content as similar as possible to each other.
Each product was evaluated organoleptically for its degradation rate, by a creepmeter for its break patterns, and by an optical microscope for its visual image.
French dressing for salads was allowed to stand for 60 min after its preparation, and separation of the vinegar and oil was determined. The separation was slower with DAG than with TAG, about 1/2 the amount of DAG to TAG separating.
Mayonnaise prepared with DAG was more favorably evaluated in terms of its appearance and texture. The results of the evaluation of breakage patterns with the creep meter and of image analysis by optical microscopy support the results obtained from the organoleptic test.
Little overall significant difference was apparent between the products prepared with DAG and those with TAG.

View full abstract

The brown alga Chorda filum (L. ) Lam., called tsuru-mo in Japanese, is harvested and consumed in only a few towns along the coast of the Japan Sea. In Sado, (Niigata), and Wajima, (Ishikawa), in Japan, the alga is dried under the sun and stored for 1 year before being sold in retail shops. The dried product of Chorda filum is washed and rubbed well with plenty of water five to ten times before cooking. We analyzed the water-soluble components in both the dried and water-washed products. The amounts of ash (58.4 to 16.2g/100g of dry matter), fucoidan (10.1 to 1.3), Na (6.83 to 1.28), K (18.0 to 1.44), and Mg (2.22 to 1.26) in the dried product were decreased by washing, and these might have been eluted in the water. However, carbohydrates (32.7 to 75.8), alginic acid (2.0 to 34.7), and Ca (2.31 to 3.16) each showed an increased contents on the dry basis after washing with water.

View full abstract

A survey was carried out on 326 students (156 males and 170 females) in order to investigate their consciousness of traditional dishes, especially traditional local cuisine, and examine their future dietary preferences which have been changing extensively in recent years.
It was revealed with statistical significance that traditional local cuisine is being continued more in joint families than in nuclear families. Over 90% of both male and female students considered that the traditional local cuisine should be continued in the future. The main reason for this among, approximately 40% was that it is considered important to maintain traditional food culture. The students of both sexes evaluated highly the healthy or tasty attributes of traditional local cuisine. The special “shiroebi” and “kanburi” dishes of Toyama were evaluated highly by over 70% of all students.
The results show that consciousness and interest in traditional local cuisine in the younger generation were fairly high and that continuing such cuisine within the families was desirable.

View full abstract