Категории: Все - oxidation

по Ummi amira 3 лет назад

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FOOD MISCELLANEOUS

Chelating agents are crucial in food preservation and are approved by the FDA for use in a variety of products, including pickled vegetables, salad dressings, and carbonated beverages.

FOOD MISCELLANEOUS

FOOD MISCELLANEOUS

Leavening agent

baking soda or baking powders

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.

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

release of carbon dioxide

produce expansion

sourdough method

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

sugar-fermenting bacteria have been allowed to develop

Yeast

initiates fermentation

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

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.

Leavening of baked foods with air is achieved by vigorous mixing that incorporates air bubbles, producing foam.
produces voluminous and strong foams that retain their expanded structure when dried by the baking process.
Egg white is well suited to this purpose
leavening may occur partially before and partially when the product is heated.
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.

Anti-caking agent

Examples
bentonite
tricalcium phosphate
silicate
Silica
microcrystalline cellulose
magnesium stearate
lactose
talcum powder
stearic acid
calcium stearate
magnesium carbonate
calcium carbonate
sodium aluminosilicate
calcium silicate (CaSiO3)
Function
coating particles and making them water repellent
adsorbing excess moisture
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.

Chelating agents

Examples:
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.

Phosphoric Acid:

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

Disodium pyrophosphate:

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

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.

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.

Ethylenediamine (EDTA):

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

Application: Chelating agents are used in a wide range of food products and are FDA-approved additives in:
Pickled vegetables
Potato products
Shortening
Salad dressings
Baking mixes
Mayonnaise
Carbonated beverages
Canned products
Metal ions
cause discoloration, off-flavors and the formation of struvite crystals.
can catalyze oxidation leading to oil rancidity as well as oxidative color changes.
cause degradative changes through a variety of mechanisms.
Some chelating agents can also act as effective antioxidants.
Destructive reactions
crystal formation
texture deterioration
color and flavor changes
rancidity
Discoloration
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

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

Humectants

Examples of humectants
polydextrose (polymeric polyols).

reduce the water molecules from migrating

Lowering the Aw

lowering the vapor pressure of a food

propylene glycol

propylene glycol is slightly bitter

the choice for more strongly flavored products

sorbitol
glycerine

Glycerin has a sweet taste

Lowering the vapor pressure of a food

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

depresses the freezing point.

helps retain moisture

used as a humectant is in dried fruits

raisins

figs

apricots

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

humectancy for polyols works through physico-chemical means.
can be used in low- to-intermediate-moisture foods where insufficient moisture for gum hydration is available.
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.

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