FOOD MISCELLANEOUS

are hygroscopic substance that promotes the retention of water, especially one used to keep a food product moist.

polyols are highly hygroscopic, which enables them to function as humectants.

Because polyols do not chemically bind with water the way many gums do

offer the advantage of not increasing viscosity in applications where it isn't wanted.

can be used in low- to-intermediate-moisture foods where insufficient moisture for gum hydration is available.

humectancy for polyols works through physico-chemical means.

polyol will lower the equilibrium vapor pressure of a formula to lower the water activity.

attracts water and reduces its availability to
migrate - a feature that has many uses in foods

Examples of humectants

glycerine

used as a humectant is in dried fruits

apricots

figs

raisins

Lowering the vapor pressure of a food

helps retain moisture

depresses the freezing point.

help fruit pieces and flavored ribbons to remain soft in frozen desserts instead of turning hard and icy.

Glycerin has a sweet taste

sorbitol

propylene glycol

propylene glycol is slightly bitter

the choice for more strongly flavored products

polydextrose (polymeric polyols).

lowering the vapor pressure of a food

Lowering the Aw

reduce the water molecules from migrating

Chelating agents are food additives that prevent oxidation and increase shelf life of baked goods.

are organic compounds with a ring-like center which forms at least two bonds with the mineral ion to produce complex structures, referred to as chelates

Metals such as calcium, zinc, iron, copper and many others can interact with components of food systems or can act as cofactors for enzymatic activity.

By binding metals, chelating agents can delay/retard these activities, thus preserving the functional and sensory properties of food products

Destructive reactions

Discoloration

rancidity

color and flavor changes

texture deterioration

crystal formation

Some chelating agents can also act as effective antioxidants.

Metal ions

cause degradative changes through a variety of mechanisms.

can catalyze oxidation leading to oil rancidity as well as oxidative color changes.

cause discoloration, off-flavors and the formation of struvite crystals.

Application: Chelating agents are used in a wide range of food products and are FDA-approved additives in:

Canned products

Carbonated beverages

Mayonnaise

Baking mixes

Salad dressings

Shortening

Potato products

Pickled vegetables

Examples:

Ethylenediamine (EDTA):

The most universally known chelating agent, EDTA serves as a multi-dentate molecule because it can form two different bonds.

Disodium pyrophosphate:

In baking, the primary function of disodium pyrophosphate is that the compound serves as a source of acid to react with baking soda resulting in leavening.

During fermentation, leavening enables rise in the product due to the formation of carbon dioxide gas creating air pockets within the crumb as well as the evaporation of alcohol.

increased water retention capacity within the baked item leading to increased moisture and longer shelf life.

Phosphoric Acid:

Functions as a chelating agent preventing oxidation caused by metal ions.

Citric Acid:

Serves the capacity to slow the rate of discoloration as well as preserve aroma. Utilized as a preservative in fruit fillings of pastries and other baked items.

additives present in many commercial table salts as well as dried milks, egg mixes, sugar products, and flour

to keep the product from forming lumps, making it better for packaging, transport, and for the consumer.

Function

adsorbing excess moisture

coating particles and making them water repellent

Examples

calcium silicate (CaSiO3)

sodium aluminosilicate

calcium carbonate

magnesium carbonate

calcium stearate

stearic acid

talcum powder

lactose

magnesium stearate

microcrystalline cellulose

Silica

silicate

tricalcium phosphate

bentonite

substance causing expansion of doughs and batters by the release of gases within such mixtures, producing baked products with porous structure.

Such agents include air, steam, yeast, baking powder, and baking soda.

leavening may occur partially before and partially when the product is heated.

Leavening of baked foods with air is achieved by vigorous mixing that incorporates air bubbles, producing foam.

Egg white is well suited to this purpose

produces voluminous and strong foams that retain their expanded structure when dried by the baking process.

Examples

Steam

During baking, as the interior of the product nears the boiling point, the vapor exerts pressure within bubbles that have been incorporated earlier by other means, producing swelling.

Yeast

initiates fermentation

which releases carbon dioxide gas and substances that affect the flavor and aroma of the baked product.

sourdough method

sugar-fermenting bacteria have been allowed to develop

When added to a fresh dough mixture, the sponge produces fermentation

baking soda or baking powders

release of carbon dioxide

produce expansion

When it is mixed with an acid liquid it releases the gas carbon dioxide (CO2).

Problem

Release gas at once

if the cake batter sits around for a while the leavening will be lost and your baked goods will be flat.