FOOD. Science. Technology. Quality

Food. SCIENCE. Technology. Quality

Food. Science. TECHNOLOGY. Quality

Food. Science. Technology. QUALITY




In polyphenols compounds changes in the industrial production process of concentrated strawberry juice


The aim of this study was to estimate changes in polyphenols contents in concentrated strawberry juice during production in the industrial scale. The samples were collected before production, after juice pressing, after juice clarification, and after juice concentration, during two weeks production in “AGRICO” company in 2005. The polyphenols compounds content including procyanidins polymers were determined by HPLC method. The derivatives of p-coumaric acid, ellagic acid, gallic acid, quercetin, kaempferol, pelargonidin, cyanidin, and especially (+)-catechin and procyanidins were identified in the samples. Among anthocyanins pelargonidin and cyaniding derivatives were determined. Quite big differentiation of polyphenols compounds content in strawberries during two weeks of production process were showed. The total amount of those compounds varied from 1970.5mg/kg to 3390.3 mg/kg. Amount of procyanidins in raw materials ranged from 1417.5 mg/kg to 2751.8 mg/kg. In comparison to raw material after pressing the amount of this polyphenols compounds was five times smaller. Procyanidins are connected to insoluble polysaccharides of cellular’s walls and it remains in the pulp. Other polyphenols compounds content differences in strawberry fruit and in juice were smaller. Further production steps such as clarification and concentration less influenced on polyphenols compounds losses. Clarification and concentration of strawberry juice result in smaller losses of polyphenol compounds in juices (17% and 5% respectively). Strawberries’ procyanidins are the most valuable compounds of its raw material, however they are being lost during production process. The main stage of strawberry juice production where the biggest amount of polyphenols compounds is lost is fruit pressing. Degradation of this compounds is smaller during clarification and concentration process.


strawberry (Fragaria x ananasa), concentrated strawberry juice, phenolic compounds