Objectives:　Many elderly people requiring long-term care suffer from oral motor disturbances. Therefore, providing them with guidance on food textures suitable to their masticatory function is very important. This study aimed to develop a method of judging masticatory function using commercially sold masticatory training food.

Methods:　Commercially sold masticatory training food was cut into a 2-gram semi-cylindrical piece using a standardized cutter. The test food was prepared by putting two semi-cylindrical pieces of different colors together to form a 4-gram cylinder. External observation of test-food mastication, and endoscopic observation of food bolus properties of flow into the pharynx were performed to assess masticatory function. Subjects’ sex, age, Food Intake Level Scale (FILS) at the first visit, eating and swallowing grade (Fujishima’s grade) after evaluation, mean mastication number, mean duration of mastication, and the relationships between these items and the food-bolus properties in the pharynx were investigated. The respective intraclass correlation coefficient (ICC) (2,1) was calculated.

Results:　The ICCs (2,1) of the masticatory movement and food-bolus properties were 0.898 and 0.964, respectively. The mean mastication number and the mean duration of mastication were significantly different due to the test-food properties (p＜0.05).

Conclusion:　This study demonstrated that external observation of test-food mastication using commercially sold masticatory training food is useful for determining masticatory function and for evaluating masticatory disturbances.

Objective:　The poor appearance of some food styles, such as blended or mashed food, negatively influences palatability, possibly leading to a loss of appetite. I think eye-tracking system can be effective in objectively determining food preference in patients individuals with communication difficulties. This study aimed to clarify the association between food preferences and gaze using an eye tracking system.

Subjects and Methods:　The study involved 50 healthy young individuals aged 20 or older. With an eye tracker unit attached to the lower part of the monitor. After that, 5 images as stimuli were randomly presented to the subjects to record their gaze. Each image contained 2 pictures of food on the left and right in the following combinations: 1）bread and sandwiches, 2）an omelet and boiled egg, 3）rice balls and rice, 4）potato chips and French fries, and 5）an apple and grated apple. After eye tracking, an interview on food preferences was conducted, while presenting the 5 images again. Subsequently, the frequency and total duration of the gaze points fixed on each food were analyzed. For statistical analysis, Wilcoxon’s signed rank sum test was used, with the significance level set at 5%.

Results and Discussion:　The subjects showed markedly higher fixation frequencies when gazing at their preferred foods. The results revealed an association between food preferences and gaze in healthy young adults.

　The author delivered an extremely low birth-weight (631 g) female infant at the gestational age of 24 weeks and 4 days. The infant was discharged to home 164 days after birth, with a weight of 3,976 g.

　Direct breastfeeding was difficult. Although she was able to ingest expressed breast milk from a bottle at a volume of approximately 500 ml/day, her intake per feeding was limited to approximately 40 ml, leading to the necessity of feeding at a frequency of 10-14 times/day. At the age of 209 days, as her milk intake began to decrease to 300 ml/day, resulting in weight reduction, nutritional management using nasal tube feeding was initiated at a volume of 600 ml/day. In consideration of future oral intake acquisition, we visited a dysphagia clinic when she was 292 days of age, and were instructed to perform swallowing training using gustatory stimulation to prepare for tube feeding. We were also notified of a possible shift of the feeding style to oral intake in about 1 year. The infant gradually became able to orally ingest small amounts, but her feeding function began to slow down at around the age of 400 days. Until that time, nasal feeding had been performed at a volume of 200 ml and intervals of 4 hours 5 times daily. From the age of 420 days, the interval was extended to 8 hours during the daytime to induce hunger, and the infant practiced oral intake. However, as her oral intake did not increase as much as expected, the nasal feed volume was reduced step by step from the age of 470 days, and this led to a gradual increase in her oral intake. The nasal tube was removed once weekly to confirm her daily oral intake, and the appropriate timing of tube removal was examined. At the age of 526 days, her feeding style was completely shifted to oral intake.

　Although nasal tube feeding is effective for temporary nutritional management, this experience suggests the necessity of predicting the period of oral intake acquisition in the early stages of nasal tube feeding, and designing step-by-step approaches for it.