The melting behavior of milk fat, hydrogenated coconut and cottonseed oils, and blends of these oils was examined by nuclear
magnetic resonance (NMR) and differential scanning calorimetry (DSC). Solid fat profiles showed that the solid fat contents
(SFC) of all blends were close to the weighted averages of the oil components at temperatures below 15°C. However, from 15
to 25°C, blends of milk fat with hydrogenated coconut oils exhibited SFC lower than those of the weighted averages of the
oil components by up to 10% less solid fat. Also from 25 to 35°C, in blends of milk fat with hydrogenated cottonseed oils,
the SFC were lower than the weighted averages of the original fats. DSC measurements gave higher SFC values than those by
NMR. DSC analysis showed that the temperatures of crystallization peaks were lower than those of melting peaks for milk fat,
hydrogenated coconut oil, and their blends, indicating that there was considerable hysteresis between the melting and cooling
curves. The absence of strong eutectic effects in these blends suggested that blends of milk fat with these hydrogenated vegetable
oils had compatible polymorphs in their solid phases. This allowed prediction of melting behavior of milk-fat blends with
the above oils by simple arithmetic when the SFC of the individual oils and their interaction effects were considered. 相似文献
Hitting the SPOT : In 1992, Ronald Frank published the first seminal paper on simultaneous parallel synthesis of multiple peptides on filter paper. He defined the approach as SPOT synthesis, an easy technique for positionally addressable, parallel chemical synthesis on a membrane support. Here, a basic overview of this technology is presented and a recently published applications are highlighted. At the end, the future of peptide arrays is discussed.