Indiana Space Grant Consortium

Three eolnmereia[ starters (A, B, and C) were selected for intensive study after several experimental cheese-making trials. Two of these were starters that produeed cheeses with open texture and fruity-fermented flavor; the third culture consistently yielded normal-flavored, close-textured product. Comparisons were made with respect to culture survival patterns during manufacture, relative rates of sugarand protein-degradation in ripening cheeses, and total carbonyl production in milk cultures. Taxonomic studies on the component strains also were conducted. No significant differences were observed in the rates of sugar-and protein-degradation between the normal (A) and defective cultures. Cultures associated with defective cheeses, however, survived the manufacturing process in greater numbers and dominated the cheese flora over longer periods of time. Furthermore, the defective cultures were found to contain high carbonyl-producing Streptococcus Iactis and Streptococc~s diacetilactis strains in contrast to Starter A, which was entirely made up of low carbonyl-produeing Streptococc~s cremoris strains and a few Leuconostoc strains. An apparent correlation between taxonomic and carbonyl-produeing characteristics of speeifie starter cultures and the quality and grade of the corresponding cheeses was shown.

Two mixed-strain lactic starters, A and C, selected for consistent production of normal and fruity-flavored Cheddar cheese, respectively, were cultured in 11% nonfat milk for 24 hr at 30 C, and the amounts and kinds of carbonyl compounds produced by each were compared. Tentative identification of 2,4-dinitrophenylhydrazones of the carbonyls showed the presence of acetaldehyde, propionaldehyde, acetone, pyruvie acid, diacetyl, glyoxal, and an alphaketo alkanal in Starter A. Starter C contained the same compounds but lacked propionaldehyde, which was replaced by formaldehyde. Striking differences were noted between A and C in the concentration of acetaldehyde, diacetyl, and pyruvie acid, the latter containing more than twice the eoneentration of these compounds found in Starter A. It appeared that cultures associated with high carbonyl production in milk also were responsible for fruity offflavor defects in Cheddar cheese.

The State of Indiana is in the process of creating a set of database tools to allow improved access, sharing, and understanding of information about community-level resources for any location within the state. This paper describes developing efforts to identify the needs of users in local government, community planning, emergency response, and agricultural extension offices to utilize the growing technical capabilities of geospatial information systems to improve environmental quality and local resource utilization for citizens of the state.

The author, Gerry Stahl, has attempted to create a large, broad book on a tremendously complex, multidisciplinary subject. This sense of scope exists on several dimensions. The 21 essays represent ...

1521 Spaceflight and weightlessness decreases skeletal muscle function and lean muscle mass due to the lack of a weight-bearing stimulus. Our previous data utilizing a ground-based model of weightlessness, unilateral lower limb suspension (ULLS), demonstrated significant decrements in human calf muscle function and size with as little as 12 days of ULLS. We hypothesized that periodic resistance and aerobic exercise performed during 17 days of ULLS would attenuate decreases in calf muscle strength and size. During 17 days of ULLS, seven male subjects performed lower leg resistance exercise with a torque velocity dynamometer on days 3, 8 and 12. Additionally, on days 4, 9 and 13 all subjects performed an incremental exercise bout up to 80% of peak VO2 on a bicycle ergometer. Calf muscle strength was tested throughout a range of seven test velocities (0 ° -300 °/s) before and after ULLS. Cross-sectional area (CSA) of the calf muscle group was measured before and after ULLS using magnetic resonance imaging (MRI). Gastrocnemius and soleus muscle biopsies were obtained on four subjects pre- and post-ULLS for histochemical and metabolic enzyme analysis. Peak isometric and isokinetic strength was maintained across all test velocities following ULLS. Further, muscle fiber composition, fiber area, capaillary density and metabolic enzymes(citrate synthase, phosphorylase, β-hydroxy-acyl coenzyme A dehydrogenase) remained unchanged. Finally, MRI revealed no significant difference in CSA of the calf muscle group following lower limb suspension. Thus, the resistance and aerobic testing protocols prevented the inactivity-induced decrements in calf muscle function and size following 17 days of ULLS.