“…The inclusion criteria was being aged between 18-65 years. The exclusion criteria were as follows: (1) salivary flow rate less than 0.1 mL/min (diagnostic criteria for xerostomia); (2) disease in the teeth, mouth, pharynx, larynx, esophagus, or respiratory system; (3) consumption of functional foods or use of oral care products that influence the oral environment during the test period; (4) mouth breather; (5) burden on the mouth, pharynx, larynx, esophagus, and respiratory system; (6) smoker; (7) heavy drinker; (8) irregular wake-up time and bedtime; (9) serious disease in the liver, kidney, heart, lung, gastrointestinal tract, blood, endocrine system, and metabolic system; chronic disease; or serious medical history of these; (10) serious food allergy, such as milk or drug allergies, or a serious medical history of these conditions; (11) pregnant, under lactation, or expected to be pregnant during the course of the study; and (12) determined as ineligible for participation in this study, judging from the principal researcher/doctor's opinions on the findings of their background. The background information confirmed by the principal researcher/doctor included recent hospital records, medication status, subjective symptoms, and basic demographics such as sex, age, body weight, and height.…”