Vesna Tumbas Šaponjac

Sour cherry pomace extract encapsulated in whey and soy proteins: Incorporation in cookies.

One of the potential sources of valuable bioactives is pomace, a by-product from fruit juice processing industry. In the presented study, bioactive compounds extracted from cherry pomace, encapsulated in whey and soy proteins, have been incorporated in cookies, replacing 10% (WE10 and SE10) and 15% (WE15 and SE15) of flour. Total polyphenols, anthocyanins, antioxidant activity and colour characteristics of enriched cookies were followed during 4 months of storage. Total polyphenols of WE10, SE10, WE15 and SE15 have shown a slight increase (23.47, 42.00, 4.12 and 1.16%, respectively), while total anthocyanins (67.92, 64.33, 58.75 and 35.91%, respectively) and antioxidant activity (9.31, 24.30, 11.41 and 12.98%, respectively) decreased. Colour parameters (L(∗), a(∗) and b(∗)) of cookies were influenced by the colour of encapsulates. Fortified cookies received satisfactory sensory acceptance as well. Encapsulated sour cherry pomace bioactives have positively influenced functional characteristics of fortified cookies and their preservation.

Bioactivity of Meeker and Willamette raspberry (Rubus idaeus L.) pomace extracts

Taking into account the substantial potential of raspberry processing by-products, pomace extracts from two raspberry cultivars, Meeker and Willamette, were investigated. Total phenolic, flavonoid and anthocyanin contents were determined. Willamette pomace extract (EC₅₀=0.042 mg/ml) demonstrated stronger 2,2-diphenyl-1-picrylhydrazyl DPPH radical-scavenging activity than did Meeker pomace extract (EC₅₀=0.072 mg/ml). The most pronounced cell growth inhibition effect was obtained in the breast adenocarcinoma cell line, reaching EC50 values of 34.8 and 60.3 μg/ml for Willamette and Meeker extracts, respectively. Both extracts demonstrated favourable non-tumor/tumor cell growth ratios and potently increased the apoptosis/necrosis ratio in breast adenocarcinoma and cervix carcinoma cells. In reference and wild bacterial strains, minimal inhibitory concentrations (MIC) were achieved in a concentration range from 0.29 to 0.59 mg/ml, and minimal bactericidal concentrations (MBC) in a range from 0.39 to 0.78 mg/ml. The results indicate significant antioxidant, antiproliferative, proapoptotic and antibacterial activities of raspberry pomace and favour its use as a functional food ingredient.

Chemical composition and potential bioactivity of strawberry pomace

This study has been designed to screen phenolic compounds of strawberry pomace obtained from two strawberry cultivars, ‘Clery’ (SC) and ‘Marmolada’ (SM), and their biological activity (O2˙−, ˙OH, DPPH˙ and ABTS+˙ antioxidant capacity, α-glucosidase inhibition and reducing power). The SM pomace contained significantly higher (p < 0.05) amounts of total flavonoids and anthocyanins, individual phenolic acids and flavonoids, among them protocatechuic acid, catechin and pelargonidin-3-glucoside (1838.31 and 1646.68 per 100 g DW, respectively) being the most abundant. The SM pomace showed higher DPPH˙ and ABTS+˙ antioxidant capacities and reducing power, as well as higher activity towards O2˙− , ˙OH (EC50˙OH = 2.77 mg mL−1) and α-glucosidase inhibitory potential (ECα-GIP50 = 1.16 mg mL−1). Our results support the use of strawberry pomace as a rich source of phytochemicals for further utilization in the food industry as supplements or ingredients for food fortification.

Encapsulation of Beetroot Pomace Extract: RSM Optimization, Storage and Gastrointestinal Stability

One of the great problems in food production are surplus by-products, usually utilized for feeding animals and for preparation of dietary fibre or biofuel. These products represent potential sources of bioactive antioxidants and colour-giving compounds which could be used in the pharmaceutical industry and as food additives. In the present study beetroot pomace extract was encapsulated in soy protein by a freeze drying method. Process parameters (core: wall ratio, extract concentration and mixing time) were optimized using response surface methodology (RSM) in order to obtain the optimum encapsulate (OE) with the highest polyphenol encapsulation efficiency (EE) and radical scavenging activity on DPPH radicals (SA). Using the calculated optimum conditions, the EE (86.14%) and SA (1668.37 μmol Trolox equivalents/100 g) of OE did not differ significantly (p < 0.05) from the predicted ones. The contents of total polyphenols (326.51 mg GAE/100 g), flavonoids (10.23 mg RE/100 g), and betalains (60.52 mg betanin/100 g and 61.33 mg vulgaxanthin-I/100 g), individual content of phenolic compounds and betalains by HPLC, and the ability to reduce Fe3+ ions, i.e., reducing power (394.95 μmol Trolox equivalents/100 g) of OE were determined as well. During three months of storage at room temperature, polyphenol retention was much higher (76.67%) than for betalain pigments, betacyanins (17.77%) and betaxanthins (17.72%). In vitro digestion and release of phenolics from OE showed higher release rate in simulated intestinal fluid than in gastric fluid. These results suggest encapsulation as a contemporary method for valorisation of sensitive bioactive compounds from food industry by-products.

Bioactive Compounds and Antioxidant Properties of Goji fruits (Lycium barbarum L.) Cultivated in Serbia

Objective: Goji fruit extracts, methanol (MGE) and hexane (HGE), were subjected to evaluation as potential source of phenolic antioxidants and antiradical activity. Methods: Some phenolic compounds (gallic, protocatechuic, vanillic, chlorogenic, coumaric, caffeic and ferulic acid and catechin and rutin), vitamin C and carotenoids were identified and quantified by HPLC. Antioxidant activity was tested by measuring ability to scavenge DPPH and hydroxyl radicals. Also, reducing power of goji fruit extracts was determined. Results: HPLC analysis results showed predominance of gallic acid (40.44 mg/g g.f). Vitamin C content in MGE was 716.91 mg vitC/100 g g.f. IC50DPPH· varied from 26.64 μmolTEAC/g for HGE to 62.15 μmolTEAC/g for MGE, while RP0.5 values varied from 952.23 μmolTEAC/g for MGE to 1360.48 mg/mL for HGE. IC50·OH for MGE was 1844.01 μmolTEAC/g. Conclusions: Our results support the use of goji fruits as rich sources of phytochemicals for further utilization in the food industry as supplements and functional food ingredients.

Effect of extraction conditions of paprika oleoresins on their free radical scavenging and anticancer activity

AbstractGround spice paprika was extracted with hexane, by conventional Soxhlet procedure (SX oleoresin), and with supercritical carbon dioxide at three different pressures — 20, 30 and 40 MPa (SF20, SF30 and SF40 oleoresins). The effect of extraction method and conditions on the colour intesity of paprika oleoresins, content of α-tocopherol, as well as antioxidant and antiproliferative activity was examined. Hexane showed highest selectivity for paprika pigments (886.02 ASTA), while α-tocopherol showed highest solubility (3846.9 mg kg−1) in supercritical carbon dioxide at 20 MPa. All paprika oleoresins exhibited good superoxide anion radical scavenging activity SF30 being the best superoxide anion radical scavenger. Cell growth activity was evaluated in vitro in human cell lines:cervix epitheloid carcinoma (HeLa), breast adenocarcinoma (MCF7) and colon adenocarcinoma (HT-29). The highest antiproliferative activity was exhibited by SX in MCF7 cell line (IC50=14.28 mg mL−1). Extract SF40 produced significant and selective antiproliferative action towards HeLa cell line. These results suggest that paprika oleoresins, due to high antiradical and tumor cell-inhibiting activity, can be regarded as functional food ingredients.

Antioxidant and Sensorial Properties of Linden Honey with Dried Apricots

The total phenol (TPh) and flavonoid contents (TFd), and antioxidant and sensorial properties of linden honey (LH) with dried apricots (20, 30, and 40%) were evaluated. TPh increased 4.3 times for LH40 (from 23.96 to 102.87 mg gallic acid equiv./100 g honey), while increase of TFd was slightly lower, ca. 2.9‐fold for LH40 (from 18.11 to 51.72 mg rutin equiv./100 g honey). Based on HPLC analysis, the most dominant phenolic compound was gallic acid (11.14 mg/100 g honey in LH and 42.65 mg/100 g honey in LH40). In three different assays, the antioxidant activity increased with increasing concentration of apricots in honey. The values varied from 13.36 for LH to 7.06 mg/ml for LH40; the values ranged from 189.83 for LH to 11.23 mg/ml for LH40; the RP0.5 (reducing power) values ranged from 169.00 for LH to 27.60 mg/ml for LH40. Based on the correlation analysis, it is obvious that TPh and TFd were associated with the antioxidant activities of honey samples. A high degree of correlation existed between antioxidant activities of honey samples and TPh (R from 0.945 to 0.996) and TFd (R from 0.805 to 0.934). Obtained scores for individual sensory properties indicated very good quality of honey with dried apricots.

Detection of Bioactive Compounds in Plants and Food Products

In addition to many essential nutritional components, plants contain various groups of biologically active non-nutrients. “Bioactive compounds” are defined as compounds that cause a specific biological response in humans and animals. Foods produced with bioactive compounds can be marketed as functional foods. Functional foods are defined as foods or food components that provide health benefits beyond basic nutrition (for the intended population). Increasing the content of bioactive compounds in foods is specifically addressed to produce new food products with improved nutraceutical values, able to prevent chronic diseases. For proper understanding of the benefits they provide, there is a need for optimized and effective protocols and methods for isolation, accurate detection and valorization of bioactive compounds, and determination of their biological effects. Accurate and reproducible identification and quantitation of bioactive compounds is essential to establish relationships between different food components and their influence on health to proclaim health benefits. Also, this is essential for establishing appropriate dietary intake levels and safety guidelines necessary (for justifying health claims) achieving desired health-beneficial properties. The aim of this work is to provide an overview on the protocols and methods presented in literature for detection of bioactive compounds, focusing on polyphenols, carotenoids, vitamin C, and tocopherols.

Encapsulated sour cherry pomace extract: Effect on the colour and rheology of cookie dough

In this study, the effect of encapsulated sour cherry pomace extract on the physical characteristics of the cookie dough (colour, textural and rheological properties) was investigated. Sour cherry pomace extract encapsulated in whey (WE) and soy proteins (SE) was incorporated in cookie dough, replacing 10% (WE10 and SE10) and 15% (WE15 and SE15) of wheat flour. The dough samples containing encapsulates had the grey-blue colour (b* values significantly decreased compared to control sample). Due to the presence of anthocyanins, a* values of the dough colour increased significantly with the addition of encapsulates. The addition of soy protein encapsulate increased hardness, resistance to extension and viscosity of cookie dough and decreased deformation compliance (J), while the addition of whey encapsulate caused dough softness, higher deformation compliance and lower values of viscosity compared to control sample. Values of storage and loss modulus, G′ and G″, significantly decreased when wheat flour was replaced with WE and increased when the flour was replaced with soy protein encapsulate. The addition of soy protein encapsulate resulted in higher cookie hardness.

Microencapsulates and extracts from red beetroot pomace modify antioxidant capacity, heat damage and colour of pseudocereals-enriched einkorn water biscuits

Cereals supply humankind with carbohydrates, proteins and several health-enhancing compounds, including antioxidants. Pomace, a by-product of beetroot juice preparation, is rich in antioxidants (phenolic compounds and betalains). The aim of this work was to study the effect of pomace extract addition, either pure or microencapsulated, on antioxidant properties, heat damage and colour of einkorn water biscuits enriched with pseudocereals. Pomace extract addition had different effects on total polyphenol contents and antioxidant capacity (FRAP and ABTS) in diverse blends. In bread, wheat and einkorn matrices, a significant increase was observed, while in pseudocereals-enriched blends, richer in antioxidants, only microencapsulation improved their content. Pomace extract addition led to furosine reduction and hydroxymethylfurfural increase. Microencapsulate-enriched WB were richest in betanin, isobetanin, total phenolics and antioxidant capacity. In conclusion, pomace extracts, by-products of juice manufacturing, significantly improve some nutritional characteristics of baked products, especially when conveyed as microencapsulates.