Particles from Proteins, Enzymes and Carrier Materials

4 Particles from Proteins, Enzymes and Carrier Materials 

Particularly for trehalose, no vacuoles inside the particles could be observed. The volume ratios of the vacuole to the powder observed by using CLSM for 300 randomly selected particles are shown in Fig. 6.15 as a function of the DE value of the carrier material of the powder. The volume ratio is nearly constant till a DE value of 11, and then decreases sharply with increasing DE value, reaching zero for trehalose. The behavior of trehalose can be easily anticipated from the results of Fig. 6.14. 

The outer surface morphology of spray-dried trehalose/alcohol dehydrogenase (ADH) powder, with the addition of diflFerent amounts of bovine serum albumin (BSA) or P-lacto-globulin (Lg) is illustrated in Fig. 6.16 (Yoshii et al., 2008). The particle surface appears smooth in the case of AD H alone, no grooves could be found. 

However, the addition of proteins (BSA or Lg) in the feed solution affects the appearance of the particles. Fine grooves appear when the mass ratios of P-Lg or BSA to ADH are higher than 0.5. The increase in protein content deforms the surface of 

CA-MD as the carrier solid. The dextrose equivalent value (DE) of MD was varied between 2 and 25 trehalose represents a very high DE value. 

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