Grainy textures

A stable crystalline form for chocolate depends primarily on the method used to cool the fat present in the Hquid chocolate. To avoid the grainy texture and poor color and appearance of improperly cooled chocolate, the chocolate must be tempered or cooled down so as to form cocoa butter seed crystals (31). This is usually accompHshed by cooling the warm (44—50°C) Hquid chocolate in a water jacketed tank, which has a slowly rotating scraper or mixer. As the chocolate cools, the fat begins to soHdify and form seed crystals. Cooling is continued to around 26—29°C, during which time the chocolate becomes more viscous. If not further processed quickly, the chocolate will become too thick to process. 

Gut I stick of the butter into 8 pieces, and pulse them with the dry ingredients until well combined. The mixture should have a sandy, grainy texture. 

Grainy textures were obtained with 22% (w/w) and higher solution concentrations, but no clear evidence of a cholesteric to nematic transition was observed. 

Milk of UF-standardized protein and total solids content enables the production of fermented dairy products of improved quality and characteristics compared with those produced from milk fortified with milk powder or evaporated milk [11]. Due to the similarity of the protein fractions in HMPP and those of skim milk and the virtual absence of lactose, Mistry and Hassan [134] suggested its utilization for the development of new dairy products and the improvement of existing ones. When these authors used HMPP to produce nonfat yogurt, they found that fortification level up to 5.6% protein can produce acceptable yogurt with smooth texture and firm body that did not exhibit whey separation even without the addition of stabilizers. They noted, however, that >5.6% protein concentration, the yogurt becomes excessively firm and has a grainy texture and flat flavor. 

In the DSC cooling curve of the LC-PI, the first exothermic peak has been confirmed to be the transition from isotropic melt to liquid crystalline phase. A grainy texture is developed within seconds when the system is cooled to just below 290°C as shown in Figure 3.9. The transition temperature and heat of transition for the sample crystallized at 280°C are independent of crystallization time,... 

Figure 3.9 Grainy texture formed during liquid crystallization.

One last factor that affects the quality of ice cream is the size of the ice crystals. For very smooth ice cream, tiny crystals are needed. To produce these, the ice cream must freeze very slowly. Large crystals give a coarse, grainy texture. Now, as you savor that premium ice cream cone, you ll know just how colligative properties and the chemistry of freezing helped make it so delicious ... 

On the other hand, the nuclei of AIST can immediately transform to smaller crystallites ( 60 nm), which form domains (F). These domains are enlarged by edge-growth crystallization (F-G) and the crystallites coalesce at the final stage (300 ns ) of crystallization in AIST (G-H). These proposed schematic models are consistent with the TEM pictures, in which GST has a grainy texture filled with 100-nm-size grains, whereas AIST has a fine texture. 

Figure 4.9 An example of a membrane electrode assembly (MEA). The membrane is a iittie larger than the electrodes that are attached. These electrodes have the gas diffusion layer attached, which gives it a grainy texture. The manbrane is typicaiiy 0.05 to 0.1 mm thick, the eiectrodes are about 0.03 mm thick, and the gas diffusion iayer is between 0.2 and 0.5-inm thick.

The typical grainy texture of the M phase. (DSCG/water, x300, crossed polars +1 A red plate.)... 

Senthil and Kannan have also reported the synthesis of liquid crystalline ferrocene-based polymers containing phosphate groups in their backbones. The molecular weights of these polymers were relatively low however, they had very narrow polydispersities. Scheme 26 shows the synthesis of polymers 106 by the polycondensation of 104 with 105. The polymers with 8 and 10 methylene spacers in their backbones possessed clear nematic textures, while most of the other polymers with shorter aliphatic chains had a grainy texture. Only the polymer with ethylene spacers and a pendent phenyl group did not show anisotropic behavior. 

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