reology of jam - parameters: shear & fruit percentage

 bibliography: rheology oh high methoxil pectin Jelly Sons prepared above and below the gelation Temperature - Cornell University  institute of food science, April 1985 . 

Notes about pectin- SSICA Parma- 

Pectin concentration, molecular weighting degree of esterification: influence on volatile composition and sensory Characteristic of strawberries jam. 

Journal of food Science 1621. 

Level of esterification in HMP (high methoxylated pectins) affects jellying formation. Optimal strength of gel correspond to level 57 -58 % . 

Hydrocolloids non only modifies viscosity but often reduces intensity of flavor, odor test . Effects depends on kind of hydrocolloids used 

Key word: DE= degree of esterification and molecular weight (of pectin). 

Adding 0,05% of pectin affects headspace of jam: some volatile compound decreases. 

Methyl 3 pantanol
2-pentanone	Fruity banana
Pentanal	Slightly fruity herbaceous nut like.
2 pentanol	fruity
3 hydroxy 2 butane	Butter
Ethyl propanoato	Fruity babana apple
Methyl butanoate	fruity
2 hexanone	Fruity sweet
3 ethoxypropanal	Butter
Butyric acid	Cheese
Hexanal	Freshly cut grass
Ethyl butanoato	Apricot
2 hexanol	Butter
Furfural	Pungent caramel
Butyl acetato	Flowery
1 hexanol	Winery,fruity, flowery
2 acetyl furan	Herbaceous , balsamic sweet
Furan	Spicy smoky
Octanal	Potato
Nerolidal	Peanut
Geraniol	Flowery
Decana	Cooked
Heptanoic acid	Unpleasent , sweet and sour
Benzaldeide	Butter almond
Decanoic acid	Unpleasant

compound volatile found in jams and their odor evaluation. 

Experiments show that adding a thickening agent affect on sensory of jam: there a decrease of typical flavors. The higher the DE (degree of esterification the higher the loss of flavor).