Gums and many modified starches in aqueous solution form gels under the proper conditions (Table 1). Gelation is usually dependent on some additional factor (temperature change and presence of divalent cations), and these properties are used during production to generate the desired degree of elasticity in the final food product. The elastic gel network prevents separation of dispersed oil and solids (eg, fruit) as well as giving a pleasing texture to the food. In most food products the external phase is water or an aqueous solution and the internal phase is a mixture of solid material or emulsified lipid. The viscosity of the product depends in part on the volume ratio of internal to external phases. Insoluble fibrous materials can physically adsorb several times their weight in water, so the addition of a small percentage of a material such as cellulose (either alpha or microcrystalline) or hemicellulose (cereal bran) will markedly reduce the amount of water, raising the internal to external phases ratio and hence the viscosity. As an example, a sauce might contain 20% solids (80% water) for an internal to external ratio of 20:80, or 0.25. Adding 5% powdered cellulose will convert about 30% of the water to the solid phase via adsorption, raising the internal to external ratio to 55:50, or 1.1, producing a marked difference in the viscosity of the sauce.

Sleeping Sanctuary

Sleeping Sanctuary

Salvation For The Sleep Deprived The Ultimate Guide To Sleeping, Napping, Resting And  Restoring Your Energy. Of the many things that we do just instinctively and do not give much  of a thought to, sleep is probably the most prominent one. Most of us sleep only because we have to. We sleep because we cannot stay awake all 24 hours in the day.

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