Novel methodologies have been developed to predict the values of sensory evaluation score by selecting the combination of measurement methods for grouping viscoelastic parameters, and coupled PLS and ANN modeling have been presented as a quality evaluation model based on the relationship analysis between viscoelastic parameters and sensory scores for Cheddar cheese. Ten Cheddar cheeses were selected as test samples and viscoelastic characteristics of the samples were obtained by three measurement methods of fracture, creep and texture tests. Thirty-eight sensory terms including 10 terms of texture attribute were selected and then sensory evaluation using the terms as well as consumer palatability test were conducted for collecting both sensory and palatability scores, respectively. The relationships between viscoelastic parameters and texture changes in human mouth were explainable by adapting the relationships between the viscoelastic characteristics and texture in the mastication process of the force vs. time curve obtained from the two bites process of the sample, and thus selection manner for the combinations of viscoelastic measurement methods corresponding to sensory texture scores were demonstrated by comparing the accuracy of PLS regression equations. Furthermore, ANN models to predict sensory texture and palatability scores were successfully presented by applying each viscoelastic parameter obtained by the selected combinations of the measurement methods. By the modeling process proposed in this study, ANN models were operational to utilize the optimal viscoelastic measurement methods contributing to the sensory and palatability scores.
To utilize blue shark Prionace glauca meat, acid-induced gel (i. e.Sujime gel) property of the fish meat, which can be produced by soaking suwari gel in vinegar, was investigated and improved. Both suwari gel and acid-induced gel could not be obtained by the same method empirically applied to other fish meats, including Alaska pollack frozen surimi. The endogenous transglutaminase activity of the shark meat was extremely low, compared to that of fishes used for gel product. The endogenous protease activity, including acid-activated protease activity, was also low. By the addition of microbial transglutaminase (MTGase), the suwari gel was formed, and excellent acid-induced gel could be obtained by soaking suwari gel in acetic acid solution. The egg white, which is one of the essential additives to prepare acid-induced gel from Alaska pollack, had no effects on the acid-induced gel property from the shark meat. Those suggest that acid-induced gel from blue shark meat can be obtained by soaking MTGase-induced suwari gel in vinegar.
Recently, remarkable progress in the fields of IT, biotechnology, space-technology has been achieved. However, it seems that only low development has been achieved in the retort sterilization technology, especially in the methods to estimate temperature of central part of foods exactly. An improved estimation method named ATS method (Ambient Temperature Slide method) was developed to solve some theoretical and practical problems in the sterilization technology in 2006. Both accuracy and convenience of the ATS method have been inspected enough so far by many experimental data, however, the ATS method have been doubted regarding propriety of assumption that the deviation rate (β) of temperature of central part of packed foods from space-mean temperature is equal to one (1). This theoretical problem could be solved by using a similarity relation between the temperature history curves of the space-mean and the central part of the packed food. In addition, it was found that a heat-transfer coefficient (h) was a very small value compared to conventional expectation by using one-dimensional finite-difference method in retort sterilization. This new finding should be investigated by further experiments.
To establish a cultivation process in high density cultivation of mung bean sprouts, heterotrophic growth behavior and the efficiency in high density cultivation were evaluated. In a growing test of mung bean in individual cultivation in test tubes and high density cultivation in single beds, courses of temperature, fresh weight, oxygen concentration, carbon dioxide concentration were measured, and specific growth rate, specific oxygen uptake rate, specific carbon dioxide evolution rate were investigated. In the individual cultivation and the high density cultivation, it was show that the growth stage was divided by different physiological states into the early stage of cultivation, the middle stage, and the late stage. When amount of sprinkled water is 0.6 t/h/cart in high density cultivation, effectiveness factor on fresh weight value maintained higher during cultivation time. Compared with 0.6 t/h/cart sprinkled water, high density cultivation with 0.4 t/h/cart sprinkled water has decreased effectiveness factor on fresh weight, and increased temperature in the lower layer and varied distribution of fresh weight and sprouts shape in a vertical direction in packed bed were investigated. These results suggest controlling the amount of sprinkled water may promote mass transfer and heat exchange, which contribute high productivity of high density cultivation.
A theoretical method to calculate the evolution of the size distribution of oil-droplets in O/W emulsions over time was proposed based on the model where the coalescence rate of two oil-droplets was expressed by second-order kinetics using the rate constant evaluated from the activation energy for coalescence. The force between two oil-droplets of different diameters was appropriated by the force between two oil-droplets of equivalent diameter, and the increase in the rate of the number density of oil-droplets was estimated by solving the mass balance equation. The evolution of the size distribution of oil-droplets in several conditions agreed well with well-known features of coalescence of oil-droplets in O/W emulsion such as instability with larger oil-droplet size.
The effect of emulsification on encapsulation efficiency of microcapsule, consisting of dextrin (wall material), methyl linoleate (core material), and polysorbate (emulsifier), was examined. In this study, normal or 2-step emulsification was adopted to improve encapsulation efficiency of the microcapsule. The results showed that the encapsulation efficiency of the microcapsule prepared by 2-step emulsification was higher than that of the microcapsule by normal emulsification. Oil droplet size distributions of emulsion prepared by both emulsifications were almost the same, but DSC curves during freezing were different. The exothermic peak of the emulsion by 2-step emulsification was shifted to a higher temperature. This shift indicated that the oil droplets in the emulsion were more dispersed. Hence, it was suggested that the dispersed state of oil droplets might affect the encapsulation efficiency.
Katsuobushi is one of the most famous Japanese traditional foods and it has been empirically known that giving moisture was effective to realize good shaving with yielding less powder. In this article, in the aim of finding scientific elucidation for this presumption, shaving experiments were carried out with varying moisture content of the Katsuobushi under the almost constant temperature as 25°C. For the experimental consistency, the moisture content of the sample was controlled by using saturated salt solutions and the commercial shaving equipment was introduced. As a result, it was found that most of the shaved product was obtained as powder if the moisture content was less than 0.5% d.b. With gradual increasing of moisture content of Katsuobushi, the powder content gradually decreased, and at the condition moisture content reached about 14% d.b., the powder content drastically decreased. By referring existing data, the glass transition temperature of Katsuobushi of 14.4% d.b. in moisture content was appeared to be about 25°C, that coincided with the sample temperature at the shaving. From the result, it would be elucidated that moistured Katsuobushi could be shaved with less powder content because the glass transition temperature of the Katsuobushi went down below the actual temperature at the shaving and the Katsuobushi turned into rubbery state.