No abstract

Strained yogurt, labneh, produced by straining cow's milk set yogurt in cloth bags, was stored at 5, 15, and 25 degrees C, and changes in microbial counts, pH, titratable acidity, percentage of free whey, and sensory attributes were monitored during storage. Counts of total aerobes, psychrotrophic yeasts, yeasts and molds, and lactic acid bacteria, except in samples stored at 25 degrees C, increased irrespective of storage temperature. The pH of samples decreased, titratable acidity and percentage of free whey increased, and texture defects were detected at a later stage than flavor changes during storage. Shelf-life data of labneh was adequately described by the Weibull distribution. The nominal shelf life determined using sensory changes and yeast counts as failure criteria ranged from 8.5 to 10.5, 4.7 to 5.8 and 2.3 to 2.7 d at 5, 15 and 25 degrees C, respectively. Q10 (shelf life at T degrees C/shelf life at T+10 degrees C) for flavor quality loss was 1.98 at 5 degrees C, and the corresponding activation energy was 11.3 kcal/mol.

No abstract

More emphasis is now being placed on active learning in medical education. Ultrasound is an active learning tool that can be used to supplement didactic instruction. This study describes a self‐guided activity for learning floor of mouth ultrasound. Thirty‐three first year medical students learned floor of mouth scan technique and ultrasound anatomy through a brief PowerPoint module. They subsequently performed the scan on a standardized patient. Each student was asked to label the floor of mouth muscles on the image he or she acquired. After the activity, the students were given a quiz on anatomic relationships of the floor of mouth. Perceptions about the activity were collected through a survey. All 33 students obtained a floor of mouth image within a three minute time limit. Twenty‐four (73%) students were able to completely and accurately label the image in time. The mean score on the muscle relationships quiz was 93%. Overall perceptions were very positive with most students expressing a “high” or “very high” level of interest in incorporating similar self‐guided activities within the curriculum. This study showed that it is feasible for students to learn scan technique and recognize relevant ultrasound anatomy in an independent fashion through a brief active learning module. Furthermore, the students found the activity enjoyable. The implication is that similar activities could be developed which would provide additional ways to incorporate active learning strategies.

The odor detection thresholds of carvacrol (5-isopropyl-2-methyl-phenol), thymol (2-isopropyl-5-methyl-phenol) and p-cymene 2,3-diol (2,3-dihydroxy-4-isopropyl-1-methyl-benzene) in sunflower oil, determined by the three-alternative, forced-choice procedure, were 30.97, 124 and 794.33 mg kg -1 , respectively. Sunflower oil containing 13, 70, or 335 mg kg -1 of carvacrol, thymol or p-cymene 2,3-diol, respectively, was judged to be similar (P \ 0.01) in taste and odor to its antioxidant-free counterpart. The rate constant of sunflower oil oxidation, measured from the increase in peroxide value during storage at 25°C, was 9.2 9 10 -9 mol kg -1 s -1 while the rate constants were 9.3 9 10 -9 , 9.8 9 10 -9 , and 4.3 9 10 -9 mol kg -1 s -1 in the presence of 13 mg kg -1 carvacrol, 70 mg kg -1 thymol, and 335 mg kg -1 p-cymene 2,3-diol, respectively. At a level of 335 mg kg -1 , p-cymene 2,3-diol did not impart flavor taints and effected a 46.7% reduction in the rate of oxidation of sunflower oil. These findings indicate that the diphenolic p-cymene 2,3-diol could potentially replace synthetic antioxidants and is a valuable addition to the antioxidants used by the food industry in its quest to meet consumer demands for synthetic-additives-free and 'natural' foods.