Valorisation of blueberry and raspberry pomace through the formulation of value-added gluten-free cookie

Sporedni proizvodi industrijske prerade voća, trop borovnice i maline, postupcima sušenja i mlevenja prevedeni su u oblik pogodan za aplikaciju u prehrambene proizvode. Ovako dobijeni sastojci imaju visok sadržaj prehrambenih vlakana, esencijalnih masnih kiselina poput linolne i α-linolenske, a karakteriše ih i izbalansiran odnos PUFA/SFA. Od makronutrijenata, u najvećoj koncentraciji prisutni su K, Mg i Ca. Imajući u vidu da su glavne fitohemikalije bobičastog voća polifenolna jediinjenja, u proizvedenim funkcionalnim sastojcima određen je sadržaj ukupnih rastvorljivih polifenola, antocijana i flavonoida, kao i sastav i sadržaj odabranih polifenolnih jedinjenja primenom LC/MS-MS tehnike. Primena osušenih i samlevenih tropova kao sastojaka prehrambenih proizvoda ispitana je u formulaciji bezglutenskog keksa, sa ciljem njegovog funkcionalnog obogaćivanja. Za optimizaciju formulacije keksa korišćen je postupak odzivne površine (RSM), a formulacija u kojoj je bezglutenska smeša zamenjena sa 28,2% tropa borovnice i 1,8% tropa maline dobijena je kao optimalna, uzimajući u obzir sve zadate kriterijume. Dodatkom ova dva funkcionalana sastojka u gorenavedenom odnosu, postignuto je značajno poboljšanje nutritivnih svojstava bezglutenskog keksa, a dobijeni proizvod po kvalitetu može da parira komercijalno dostupnim funkcionalno obogaćenim keksovima, namenjenim zdravoj populaciji. Rezultati dijetetske interventne studije sprovedene na 20 zdravih, normalno uhranjenih ispitanika ženskog pola, ukazuju da se konzumiranjem kreiranog bezglutenskog keksa u količini od 32 g dnevno, postiže značajna redukcije LDL holesterola, i povećanje nivoa adiponektina u krvi, a budući da se ovaj adipocitni-sekretorni protein dovodi u vezu sa antiinflamatornim i antiaterogenim potencijalom u tretmanu metaboličkog sindroma i dijabetesa tipa 2, može se očekivati protektivno dejstvo kreiranog bezgutenskog keksa.Blueberry and raspberry pomace, by-products from fruit juice industry, were processed into the new food ingredients by drying and grinding. The obtained functional ingredients are characterized by high content of dietary fibres and essential fatty acids (linoleic and α-linolenic acid), as well as by optimal ratio of PUFA/SFA. The main macronutrients in dried and ground pomace are K, Mg and Ca. The content of total phenolic compounds, anthocyanins and flavonoids were determined, as well as composition and content of individual phenolic compounds using LC/MS-MS in order to evaluate their antioxidant potential. In the form of dried powder, blueberry and raspberry pomace were used as ingredients in formulation of gluten-free cookies. Response surface methodology (RSM) approach was applied to obtain optimal ingredients proportion. Formulation in which gluten-free flour mixture is substituted with 28.2% of the blueberry and 1.8% of the raspberry pomace was found to be optimal following the used optimization criteria. Addition of blueberry and raspberry pomace has led to a remarkable improvement in nutritional properties, and resulted in a product with similar nutritional profile with commercially available gluten containing cookies. Dietary intervention study on a group of 20 healthy, normal weight female subjects was conducted to investigate the health effect of the created gluten-free cookies. The results showed a significant reduction in levels of LDL cholesterol, and an increase in plasma concentrations of adiponectin, suggesting a potential positive effect of the created product on human health