BLUEBERRY JUICE ENCAPSULATED ON MALTODEXTRIN: THE IMPACT ON THE PROPERTIES OF WHITE CHOCOLATE

Abstract

The lower content of phenolic compounds in white chocolate makes this confectionery product unhealthier and, thus, adequate for enrichment compared to other types of chocolates like dark or milk. Less phenolics in white chocolate is due to absence of dark cocoa solids, abundant in these compounds. This study aimed to develop a new product with a higher nutritional value than regular white chocolate by enriching white chocolate with blueberry juice as a natural source of polyphenols. Since phenolic compounds are highly sensitive to heat, light, oxygen, and pH, encapsulated form of blueberry juice was used to increase their stability in the product. Blueberry juice was encapsulated on maltodextrin (B/M) and added to white chocolate at 80 g/kg and 100 g/kg concentrations. Enrichment significantly (p<0.05) increased the content of total dietary fibres and carbohydrates in the white chocolate and decreased proteins and total fats. The addition of the encapsulates significantly (p<0.05) impacted all particle size parameters, especially volumeweighted mean D[3,4] which increased (14.38 μm for B/M80 and 16.00 μm for B/M100) compared to the control (13.06 μm). Rheological properties are of great importance for products like chocolate and the incorporation of the encapsulates significantly (p<0.05) increased the values of rheology parameters like Casson viscosity (1.04 Pa s for B/M80 and 1.21 Pa s for B/M100). Likewise, enrichment significantly (p<0.05) decreased the hardness of the sample (B/M80) compared to the control. Furthermore, the content of total polyphenols and antioxidant capacity significantly (p<0.05) increased following the added concentration of the encapsulates. The highest content of total polyphenols and antioxidant capacity was observed in the chocolate sample enriched with 100 g/kg of encapsulate. The colour of the enriched samples significantly (p[removed]0.05) except for the sweetness. The enriched chocolate samples were less sweet. The results of this study indicate the potential of maltodextrin as a carrier of sensitive bioactive compounds for the enrichment of products like white chocolate.

Niži sadržaj fenolnih jedinjenja u beloj čokoladi čini ovaj konditorski proizvod manje zdravim i time adekvatnim za obogaćivanje u odnosu na druge vrste čokolade, crnu ili mlečnu. To se dešava zbog odsustva tamnih čvrstih delova kakaoa u beloj čokoladi, bogatih ovim jedinjenjima. Naše istraživanje je imalo za cilj da razvije novi proizvod sa većom nutritivnom vrednošću od obične bele čokolade. Poznato je da su fenolna jedinjenja veoma osetljiva na toplotu, svetlost, kiseonik i pH, i zbog toga je bilo potrebno njihovo inkapsuliranje na maltodekstrinu. Sok od borovnice, kao izvor polifenola, inkapsuliran je na maltodekstrinu (B/M) i dodat u belu čokoladu u količini od 80 g/kg, odnosno 100 g/kg. Obogaćivanje bele čokolade značajno je (p<0.05) povećalo sadržaj ukupnih dijetetskih vlakana i ugljenih hidrata uz smanjenje sadržaja proteina i ukupne masti. Dodavanje inkapsulata značajno je (p<0.05) uticalo na sve parametre veličine čestica, posebno na vrednost zapreminsko srednjeg prečnika D[3,4] koja je povećana (14.38 mm za B/M80 i 16.00 mm za B/M100) u poređenju sa kontrolom (13.06 mm). Reološka svojstva su od velikog značaja za proizvode kao što je čokolada, a inkorporacija inkapsulata značajno (p<0.05) povećava vrednosti reoloških parametara kao što je Cassonov viskozitet (1.04 Pa∙s za B/M80 i 1.21 Pa∙s za B/M100). Isto tako, obogaćivanje je značajno (p<0.05) smanjilo tvrdoću uzorka (B/M80) u poređenju sa kontrolom. Štaviše, sadržaj ukupnih polifenola i antioksidativni kapacitet značajno su porasli (p<0.05) nakon dodavanja određene koncentracije inkapsulata. Najveći sadržaj ukupnih polifenola i antioksidativni kapacitet uočen je u uzorku čokolade sa 100 g/kg inkapsulata. Boja obogaćenih uzoraka značajno se (p<0.05) razlikovala od kontrolnog uzorka. Uticaj dodatog inkapsulata na senzorna svojstva nije bio značajan (p>0.05) osim slatkoće. Uzorci čokolade koji su obogaćeni bili su manje slatki. Rezultati ove studije ukazuju na potencijal maltodekstrina kao nosioca osetljivih bioaktivnih jedinjenja za obogaćivanje proizvoda poput bele čokolade.