The hardness (a parameter obtained from texture profile analysis) and viscosity of thickener solutions with different flow properties (viscosity (μ) vs. shear rate (γ̇)) were measured for care foods for dysphagic patients. In addition, the correlation between hardness and velocity of food through the pharynx was investigated. Carboxymethyl cellulose (CMC) and locust bean gum solutions were almost considered Newtonian fluids, while solutions of xanthan gum and commercial thickening powder showed similar shear thinning. Plots of μ at a shear rate of 3 s-1vs. hardness were well fitted with a straight line. However, plots of μ at a shear rate of 25 s-1 and 50 s-1vs. hardness could be fitted with two different straight lines for solutions with different flow properties. As the values of hardness and viscosity increased, a decrease was observed in the maximum velocity through the pharynx, Vmax, which has been reported to be a good predictor of aspiration risk. These results confirm that the flow properties of solutions should be considered when substituting hardness for viscosity as an index for care food for dysphagic patients.
To produce a novel Mozzarella cheese, the homofermentative lactic acid bacteria (LAB) Streptococcus salivarius ssp. thermophilus, isolated in Hokkaido, was chosen from the authors’ originally constructed LAB library. Physiological analysis of this strain indicated relatively weak acid production. To use this LAB as starter bacteria to produce mozzarella-type cheese, citric acid was used as a supplement to decrease the pH. Thus, the manufacturing method using both lactic acid fermentation and pH adjustment was established for the mozzarella cheese. The mozzarella cheese made using this manufacturing method exhibited good flavor. Consequently, we demonstrated that the originally isolated strain could be applied to the cheese manufacturing process without the need to select variants that are tolerant to severe culture conditions. Therefore, this result indicated that wild strains might be applied to cheese manufacturing without the need for laborious pre-selection considerations.
In order to develop fish paste products with novel textures, “rice gel” prepared from high-amylose rice porridge was mixed with walleye pollock surimi, and a heat-induced gel was prepared. The physical properties of the gel were investigated by dynamic viscoelastic measurement and penetration test. High-amylose rice gel showed high emulsifying properties when mixed with oil. When the emulsified rice gel was mixed into walleye pollock surimi, both directly heated gel and two-step heated gel yielded greater breaking strength and break strain when compared to the same gels without oil. In particular, the two-step heated gel showed unique properties that differed from the conventional Kamaboko gel. Moreover, when the emulsified high-amylose rice gel was added to surimi, the changes in the physical properties of directly heated gel and two-step heated gel were different with regard to both penetration test and dynamic viscoelasticity measurement results.
In this study, a process for making softened green broccolis prepared with freeze-thaw impregnation of macerating enzymes was clarified. Blanching and freeze-thaw processes were required to achieve the corresponding firmness. The process that contributed the greatest to softening was an enzymatic reaction. The softened broccolis prepared with freeze-thaw impregnation of macerating enzymes exhibited 1/5∼1/6 firmness values compared with broccolis boiled for 6 or 10 minutes, and did not show significant differences in ascorbic acid contents and colorimetrically-determined a* values. These results suggested that the freeze-thaw impregnation of macerating enzymes is an effective method to produce adequately softened green vegetables.
We conducted a milk-clotting test and evaluated a model curd with the aim of making a new cheese using soybean and adzuki bean broths. Milk clotting time was slowed by the polyphenols contained in the bean broth; however, there was no significant difference in the curd yield with broth addition up to 40% (v/v), and a good model curd was formed. The appearance of the model cheese made with 30% (v/v) broth reflected the color tone of each broth type. This indicates the possibility of producing a new cheese in which the polyphenols contained in bean broths are incorporated into the cheese curd.
In Japan, the cultivation of new wheat varieties for use in bread and in Chinese and other noodles is an important and urgent objective for increasing the domestic wheat production and the food self-sufficiency ratio. Many molecular markers are currently available; those used in wheat breeding programs in Japan are generally employed to assess the amylose content, dough strength, grain hardness, wheat yellow mosaic virus, and preharvest sprouting. Molecular markers for flour color and grain yield will be developed in the next few years.
Glutenin subunit composition, amylose content, and grain hardness are critical determinants for the end-use properties of wheat. Glutenin composition determines gluten strength, which is important for bread-making. Lower amylose content increases springiness, which is important in white salted noodle production. Grain hardness affects the damaged starch content in flour ; a high damaged starch content increases water absorption and facilitates dough fermentation. These qualtiy attributes are genetically determined. Here, I review these genetic traits based on their allelic variation in imported wheat classes and domestic wheat cultivars. It is thus potentially possible to optimize the allelic compositions of these traits in order to improve the end-use properties of domestic wheat cultivars.