THE INFLUENCE OF ADDITION OF DEFATTED BLACKCURRANT
SEEDS ON PRO-HEALTH CONSTITUENTS AND TEXTURE OF
CEREAL EXTRUDATES
DOROTA GUMUL
1,4
, RAFAL ZIOBRO
1
, TOMASZ ZIE ˛BA
2
and EDWARD RÓJ
3
1
Department of Carbohydrate Technology, University of Agriculture, Balicka 122, Krakow 30-149, Poland
2
Department of Food Storage and Technology, Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
3
Fertilizers Research Institute, Supercritical Extraction Department, Pulawy, Poland
4
Corresponding author. TEL: +48-12-6624771;
FAX: +48-12-6624747; EMAIL:
rrgumul@cyf-kr.edu.pl
Received for Publication November 15, 2010
Accepted for Publication October 3, 2011
doi:10.1111/j.1745-4557.2011.00418.x
ABSTRACT
Extrudates used in the study were prepared on the base of cornmeal (100%) –
control, which was in 10, 30 and 50% replaced by defatted seeds of blackcurrant,
which were a by-product of supercritical fluid extraction, used for oil production.
The aim of the study was to check the influence of the level of defatted blackcurrant
seeds, on texture and chemical composition of the obtained extrudates. Special
attention was paid to pro-health constituents, i.e., dietary fiber, polyphenols, fla-
vonoids and anthocyanins. The addition of defatted seeds resulted in an increase of
polyphenol content, and antioxidant activity, and the rise in the level of flavonoids
and soluble dietary fiber as compared with control. The enrichment of extrudates in
pro-health components, as well as improvement of sensory score, suggests that 10%
addition of defatted blackcurrant seeds is a suitable level for preparation of extruded
fruit-cereal snacks.
PRACTICAL APPLICATIONS
The study demonstrates that defatted blackcurrant seeds could be a good, natural
source of bioactive components in cereal snacks produced by extrusion. The sug-
gested level of this component, optimal from sensory and dietary point of view, is
10%.
INTRODUCTION
Dietary fiber and polyphenols are important pro-health com-
ponents, which should be present in the human diet. Dietary
fiber, especially its soluble fraction, plays an important role in
human nutrition, because it lowers blood cholesterol, reduces
risk of cardiovascular disease, prevents colorectal cancer and
exerts other pro-health activities (Anderson 2003; Esposito
et al. 2005; Bravo 2007). Polyphenols constitute the main
group of plant antioxidants, and thus play an important role
in preventing cardiovascular diseases, and several types of
tumors (Astley 2003; Scalbert et al. 2005). The content of
soluble fiber and polyphenols in cereals is usually low (Ragaee
et al. 2006; Fardet et al. 2008), in contrast to berry fruits,
which contain high levels of those bioactive compounds
(Piesiewicz and Bartnikowska 1997; Borowska 2003; Szajdek
and Borowska 2008). Such a beneficial composition is not
only typical for fresh berry fruits, but also for the off-products
obtained in various branches of food industry, such as
pomace (Hilz et al. 2005), and defatted seeds (Rój et al. 2009).
The last product is obtained during oil extraction with super-
critical carbon dioxide, and has a high pro-health potential as
an additive, because of high amounts of dietary fiber and
polyphenols. Supercritical fluid extraction with CO2 is con-
sidered to be a safe method in food processing, because it does
not require the use of toxic solvents and high temperatures
(Brunner 2005; Pereira and Meireles 2010). It seems that the
valuable off-products obtained during oil extraction from
various plant materials should be utilized as a source of
important bioactive compounds in the food industry.
Recently, a successful trial to use defatted strawberry and
blackcurrant seeds as functional ingredients for gluten-free
Journal of Food Quality ISSN 1745-4557
395 Journal of Food Quality 34 (2011) 395–402 © 2011 Wiley Periodicals, Inc.