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U prezentaciji je predstavljena osnova procesa ekstruzije i proizvodnje ekstrudiranih proizvoda te primjeri primjene različitih nusproizvoda prehrambene industrije u proizvodnji nutritivno vrjednijih ekstrudiranih proizvoda s naglaskom na prikaz dobivenih rezultata u sklopu projekta FUNEXFOOD.

Cold plasma is used in food industry for food decontamination and surface treatment of packaging. It has been proven to have influence on different compounds, showing potential for application in inactivation of toxins, degradation of pesticides as well as in modification of properties of protein, starch and fiber. The aim of this research was to investigate influence of cold plasma treatment on modification of tapioca starch. Tapioca starch was treated with cold plasma, Na2HPO4, Na5P3O10, and by combination of plasma treatment with each chemical modification. Gelatinization properties (by DSC), paste properties (by micro viscoamylograph), swelling power and solubility, and paste clarity (spectrophotometrically) were determined and results showed that cold plasma treatment decreased gelatinization temperatures and increased gelatinization enthalpy, increased swelling power and solubility, reduced paste clarity and had no significant effect on paste viscosity. When combined with chemical modifications, cold plasma entangled influence of chemicals, reducing their influence on swelling power, solubility and paste clarity and improving their influence on gelatinization properties and paste viscosity.

Fruits are rich in several bioactive compounds and as such represent the simplest form of functional foods. Some of the bioactive compounds found in fruits showed to have great impact on human's enhancing human health and preventing disease. One of the more important bioactive compounds with impact on human health are polyphenols. Processing of fruits into fruit products result with high amounts of by-product material rich in polyphenols. One of such by-product is the residue of pressed grapes, grape pomace. The extraction of polyphenol from grape pomace has been well studied and numerous methods for polyphenolic extraction are developed. However, there are new extraction techniques which give better yields and higher stability of polyphenols during extraction. The aim of this work was to investigate the effect of cold plasma and ultrasound on the extraction of polyphenolic compounds from dried grape pomace. Cold atmospheric plasma assisted extraction was conducted by using aqueous solution of ethanol or methanol acidified with hydrochloric acid (49.5:49.5:1) and the influence of frequency and treating time were tested. Ultrasound extraction was conducted by using the same solvents, however in this case the influence of temperature and treating time were tested. Total polyphenols were determined by Folin- Ciocalteu spectrophotometric method. The highest yield of polyphenols (30.2 mg/100g) was achieved using aqueous solution of ethanol at frequency 100 Hz, and treating time, 15 min. Considering ultrasound the highest yield of polyphenols (6.0 mg/100g) was achieved using aqueous solution of ethanol at 80 °C, and treating time, 15 min. Antioxidant activity (AOA) of samples was determined by DPPH method. The highest AOA (1.28 moltrolox/ml) was measured in grape pomace extracts obtained by using aqueous solution of ethanol at frequency 100 Hz, and treating time, 15 min. In samples treated with ultrasound, the highest AOA (0.89 moltrolox/ml) was achieved using aqueous solution of ethanol at 80 °C, and treating time, 15 min.

Extruded snack products are one of the most popular snacks consumed worldwide. Usually they are not fortified with nutrients, but they can be very good source of nutrients, because of their prevalence. Consequently, the objective of this research was to increase nutritional value of the extruded corn-based snacks with wheat enriched with selenium (Se). Se is important for reduction of hydroperoxide, because glutathione peroxidase (GPX) is dependent on Se, and GPX catalyzes reduction of hydroperoxide. Except as antioxidant, Se has important part in maintaining thyroid hormone homeostasis, has role in reproduction, immunity, aging process, protection against heavy metal poisoning. Lack of Se can be associated with various diseases, including cancer, due to its antimutagenic and anticancer properties. Since poisoning with Se is also possible, there are recommendations for daily intake which amount to about 55 μg for adults. Wheat enriched with Se was milled to flour and flour was added to corn grits in 10, 20, 30, 40% d. m., and mixture moisture was set to 15%. Prepared samples were extruded in laboratory single screw extruder with 4 mm round die, screw with compression ratio of 4:1, at temperature profiles: 140/170/170 °C ; 150/180/180 °C and 160/190/190 °C. Obtained extrudates were air-dried and physical properties were determined. Addition of flour increased total color change (ΔE) in obtained extrudates, but increasing temperature of extruder did not have significant influence on ΔE. Both flour addition and increasing temperature of extruder had influence on expansion ratio (ER), but not so much on bulk density (BD). The highest ER values had snacks with 10 and 20% added wheat flour, extruded at temperature profile 140/170/170 °C. Increasing temperatures of extruder and addition of flour decreased ER. Both parameters decreased fracturability of extrudates and did not show significant influence on hardness. Wheat enriched with selenium was successfully incorporated in extruded snack products based on corn grits. Since selenium is important mineral for humans, this can be a good example for development of new functional products.

Osnovne sirovine za proizvodnju glukozno- fruktoznih sirupa (GFS) su saharoza ili škrob. Zbog niže cijene proizvodnje, danas na tržištu prevladavaju GFS-i na bazi škroba. Škrobni sirupi se dobivaju cijepanjem α-1→4 i/ili α-1→6 glikozidnih veza molekula škroba (amiloze i amilopektina) procesom koji se naziva hidroliza škroba. Za proizvodnju škrobnih GFS-a koristi se 95 %-tni glukozni sirup koji se tretira s enzimom glukoza izomerazom, koji izomerizira glukozu u fruktozu. Hidrolizom saharoze nastaje smjesa glukoze i fruktoze (invertni šećer), a provodi se pomoću kiselina ili enzima invertaze. GFS-i imaju široku primjenu u prehrambenoj i farmaceutskoj industriji, a u pčelarstvu se koriste za prihranu pčela te, nažalost, i za patvorenje meda.

Ambalažni materijali imaju široku primjenu u svakodnevnom životu potrošača i u industriji. Velika količina nepovratne plastične ambalaže postala je ekološki problem, a moguće rješenje predstavlja razvoj biorazgradljivih polimera. Biorazgradljivi polimerni materijali proizvode se različitim postupcima iz obnovljivih izvora životinjskog ili biljnog podrijetla i mogu se razgraditi kompostiranjem na ugljikov dioksid, vodu, anorganske sastojke i biomasu. Tijekom tog procesa ne stvaraju se nikakvi štetni spojevi. Istraživanja pokazuju da ambalaža od biorazgradljivih polimera sprječava gubitak vlage u pakiranju, smanjuje oksidaciju lipida i poboljšava okus plodova, povećavajući njihovu trajnost i mikrobiološku stabilnost. U ovom radu provedena su ispitivanja toplinskih svojstava diferencijalnom pretražnom kalorimetrijom (DSC) i termogravimetrijskom analizom (TGA) mješavina biorazgradljivih polimera, polilaktida (PLA) i termoplastičnog škroba (TPS). TPS je pripremljen s različitim udjelima glicerola kao plastifikatora. Zbog hidrofilne prirode TPS-a ispitana je i apsorpcija vode PLA/TPS mješavina. Termoplastični škrob utječe na porast stupnja kristalnosti PLA u ispitivanim mješavinama, dok PLA utječe na porast toplinske stabilnosti TPS- a. Utjecaj glicerola kao plastifikatora TPS-a nema značajnu ulogu u ispitivanju toplinskih svojstava, dok je ispitivanje apsorpcije vode pokazalo da se uz veći udio glicerola dobivaju niže vrijednosti apsorpcije vode.

The impact of cold atmospheric plasma (CAP) and ultrasound (US) assisted extraction on gallic acid, p-coumaric acid, catechin, epicatechin and quercitin from dried grape pomace was investigated. The solvents used for the extraction were aqueous solution of ethanol or methanol, acidified with hydrochloric acid (49.5:49.5:1). The investigated parameters in case of CAP were tretment time (5, 10, 15 min) and frequency (20, 50, 100 Hz), and in the case of US, treatment time (5, 10, 15 min) and temperature (20, 40, 80°C). The results showed that in both cases the better extraction solvent was ethanol acidified with hydrochloric acid. The highest yields in extracts obtained by CAP assisted extraction have been achieved by extracting polyphenols at 100 Hz for 15 min. The contents of gallic acid, p-coumaric acid, caffeic acid, catechin, epicatechin and quercetin were 4.21 ; 6.80 ; 54.09 ; 53.68 ; 53.19 ; 45.31 mg/100g DW, respectively. In extracts obtained by US assisted extraction, the highest content of investigated polyphenols have been achieved by extracting polyphenols at 80 °C for 15 min. The contents of gallic acid, p-coumaric acid, caffeic acid, catechin, epicatechin and quercetin were 2.32 ; 5.87 ; 36.19 ; 40.25 ; 23.02 ; 24.97 mg/100g DW, respectively. Contents of all investigated polyphenols were higher in extracts obtained by CAP assisted extraction.

Volatile organic compounds represent a fingerprint of a specific honey and therefore could significantly affect the quality of mead (honey wine). Mostly this substance are grouped in to chemical categories such as aldehyde, ketone, acid, alcohol, hydrocarbon, terpenes and benzene compounds and their derivatives, furan and pyran derivatives. The aim of this research was to assess the impact of immobilized cell fermentation on volatile aroma of MEAD (honey wine). Aroma profile was determined using GC/FID and sensory analysis was conducted according to German DLG model. Results showed that immobilized cell technique gives honey wine with lower ester contents, but significantly higher content of volatile organic compounds from honey.

Wheat flours, Kraljica and Olimpija, and hulless barley flours, Mandatar and Osvit, were extruded in a single screw extruder at 25, 30 and 35% moisture level and extrusion die head temperature of 90, 100 and 110 °C. The effects of extrusion conditions on water absorption (WAI) and solubility (WSI) indices, and colour parameters were determined. The extrusion process significantly increased water absorption of flours , with the highest values of WAI obtained at higher moisture content and higher die head temperature. The higher moisture content led to the hgiher values of WSI for both wheats with the highest values obtained at 35% moisture content and 110 °C. Both barley extruded flours showed minor decreases in WSI compared to the native flours, with higher WSI values for the higher moisture content. All colour parameters were significantly affected by the extrusion process. The total colour change parameter (∆E) had the lowest values for flours extruded at lowest moisture content. The results suggest that extrusion of wheat and barley flours allows modifying flour features and might be an alternative to obtain flours with different functionality, depending on the extrusion conditions.

Cocoa shell, a by-product of cocoa industry, is valuable source of dietary fibers, phenolics, methylxanthines and vitamins. Recently, the presence of high-valuable bioactive components in cocoa shell was recognised and the pallet of food products enriched with cocoa shell is increasing. The most abundand bioactive components of cocoa shell are methylxanthines (theobromine and caffeine) and flavanols (catechins, epicatechins and procyanidins). Cold plasma treatment is often used for decontamination of products but also effects food constituents. The aim of this study was to determine bioactive components profile of cocoa shell and evaluate the effect of cold plasma treatment of their composition and content. Qualitative and quantitative determination of 6 phenolic components (gallic acid, caffeic acid, p-coumaric acid, (+)-catechin, (-)-epicatechin and (-)-epicatechin gallate) and 2 methylxanthines (theobromine and caffeine) was performed by chromatographic method with absorbance detection while total phenolic content was determined by Folin-Ciocalteu method. The results showed that theobromine, caffeine and (+)-catechine are major bioactive components of cocoa shell followed by gallic acid and (-)-epicatechin. Although water extraction decreased bioactive components content compared to untreated cocoa shell, the decrease was lower when cold plasma treatment was applied.

Fumonisins are naturally occurred Fusarium mycotoxins, which mainly contaminate maize and its by-products, especially during heavy rainy periods and in case of substantial temperature changes during the maize growth and harvesting period. The combination of processing time and temperature applied during thermal processing of cereals remains one of the most important methodologies through which industrial processing can reduce mycotoxin content. In order to establish the effect of thermal processing on the total fumonisin content in naturally contaminated maize, this study made use of cooking, roasting and extrusion cooking, run at different temperatures (100 – 220 °C) for a different length of time (10 – 30 min). Before and after treatment, contaminated maize samples were analysed for fumonisin content using a validated enzyme-linked immunosorbent assay (ELISA). In comparison with cooking, which yielded a negligible mean fumonisin content reduction (up to 5%), roasting and extrusion resulted in a significantly higher fumonisins’ reduction (by 62% and 96%, respectively). A significantly higher (p < 0.05) and almost complete fumonisins’ reduction was achieved with extrusion at the highest temperature regime (135/190/190 °C - extruder’s dosing/compression/ejection zone). The results show that roasting and especially extrusion are effective and valuable methods able to significantly reduce maize fumonisin content.

he scope of my research covers the preparation and characterization of biomaterials, poly(lactic acid) (PLA), poly(epsilon- caprolactone) (PCL) and thermoplastic starch (TPS). After that the characterized biomaterials were exposed to biodegradation through composting process. The composting process was conducted in an adiabatic closed reactor for 21 days. The biomaterials were mixed with composting substrate (bio waste) and during composting process it was monitored temperature, pH-value, % moisture and volatile matter and evolved CO2. The thermophilic phase prevailed in the composting process, indicating intensive biodegradation of substrate and biodegradation of investigated biomaterials. During biodegradation study it was notices that the percentage of biodegradability increased with the increase % of TPS in blends. SEM analysis revealed the formation of pores, cavities, discontinuities, and cracks resulting from the time beneath the compost. Since, the microorganisms use starch as a carbon source, higher concentration of TPS causes considerable acceleration of biodegradation of PCL and PLA. During composting process all investigated materials showed a high degree of biodegradation, but to obtain higher percentage of biodegradation it will be good to prolonged time of composting process or to inoculate some microorganisms which can enhance biodegradation of materials.

Extrusion is a popular process often used for the modification of flours with the aim to improve their properties. The aim of this study was to investigate the properties of corn flours obtained by milling of corn grits extrudates produced with addition of cocoa shell aqueous extracts. The extracts were prepared by using cold plasma as innovative technology and included extraction under following conditions: 1) ratio cocoa shell : water = 1 : 50, cold plasma frequency 100 Hz for 60 min ; 2) ratio cocoa shell : water = 1 : 30, cold plasma frequency 100 Hz for 30 min. The obtained extracts were added in corn grits in order to prepare the samples with 15% moisture content. Prepared samples were extruded in the laboratory single screw extruder at two different temperature profiles: 1) 135/170/170 °C ; 2) 155/185/185 °C, by using screw with compression ratio 4:1 and die with 4 mm diameter. Obtained extrudates were air-dried, milled and physical and rheological properties of flours were determined. The obtained results showed the extrusion process significantly changed all investigated properties of flours in comparison with non-extruded sample. Water absorption index (WAI) and water solubility index (WSI) increased, where the higher temperature profile had a greater effect. Damage of starch (DS) increased and resistant starch (RS) content decreased after extrusion process, regardless of the type of extract. The obtained results for rheological properties indicate the extrusion process decreased peak viscosity as well as that the extruded samples were less prone to retrogradation.

Nowadays extrusion is an important process in food industry due to the HTST (High Temperature Short Time) effect that is applied in many processes. It is used to produce a wide variety of products, from modified starch and flours, over pasta and meat products, to snack and confectionary products. Although it is considered to be an HTST process, it still may result in the formation of acrylamide and other compounds potentially harmful for human health. To overcome this issue, extrusion assisted with supercritical CO2 has been introduced, opening the possibility to obtain products of retained quality at lower temperatures. The aim of this paper is to give a short overview of research on extrusion with supercritical CO2 and address some issues related to it.

Oilseed cakes are generated as a by-product in the production of oil. They represent a rich source of protein and dietary fibers, so in the recent years started their application in the production of various types of food products, mainly bakery (bread, biscuits, tortillas) and protein supplements. One of the areas where new product development, including application of oilseed cakes, can have large impact is most certainly production of extruded snack products, which are consumed worldwide, by all age-groups from toddlers to seniors. The objective of this research was to increase nutritional value of the extruded corn-based snacks with pumpkin (Cucurbita pepo L.) oilseed cake, which is defatted by supercritical CO2 extraction. Defatted pumpkin cake (DPC) was added to corn grits in 3, 6 and 9% d. m., and 1% of pectin was added with the aim to produce products with properties of ready-to-eat snacks. Prepared samples with 15% of moisture content were extruded in the laboratory single screw extruder at temperature profile 135/170/170 °C, using a screw with compression ratio 4:1 and die with 4 mm diameter. Obtained extrudates were air-dried overnight, and physical properties of extrudates were determined. The obtained results showed that addition of DPC resulted in decrease of expansion ratio (ER) and increase of bulk density (BD) of obtained snack products. Furthermore, addition of DPC and extrusion process resulted in significant colour change, where the total colour change (ΔE) increased proportionally to the amount of DPC. Extrusion process resulted in the increase of water absorption index (WAI) and water solubility index (WSI). Final conclusion is that the extruded corn snack products were successfully improved with DPC, which is rich in nutritional components, and this can be a good example for development of new products.

Cilj ovog rada bio je ispitati utjecaj fermentacije s imobiliziranim stanicama kvasca na profil arome i senzorska svojstva destilata proizvedenih od rogača (Ceratonia siliqua L.), koji se obično uzgaja u primorskom području Republike Hrvatske. Uzorci destilata proizvedeni i postupkom klasične fermentacije te tehnologijom s imobiliziranim stanicama kvasca. Aroma profil dobivenih destilata određena je primjenom GC/FID metode, a senzorska analiza prema standardnoj njemačkoj DLG metodi. Dobiveni rezultati pokazali su da tehnika s imobiliziranim stanicama kvasca daje destilate s većim udjelom etanola i manjom količinom estera, uz zadovoljavajuću senzorsku kvalitetu. Stoga se može zaključiti da fermentacija s imobiliziranim stanicama kvasca predstavlja obećavajuću tehniku za proizvodnju destilata od rogača (Ceratonia siliqua L.).

Extruded snack products are popular among all age groups. Various by-products can be incorporated into the extruded snacks, and one such product is Camelina sativa L. cake, a by-product of oil production, rich in polyphenols, fibre, and protein. Defatted Camelina sativa L. cake (DCC) was added to corn grits in ratios of 3, 6, and 9% d. m., 1% of pectin was added and the moisture of the mixture was set to 15%. The prepared samples were extruded in a laboratory single screw extruder with a 4 mm round die, screw compression ratio of 4:1, at the temperature profile 135/170/170 °C. The obtained extrudates were air- dried and their physical properties and their soluble and insoluble dietary fibre content were determined. The obtained results showed that the addition of DCC resulted in a decrease of the expansion ratio (ER) and an increase of bulk density (BD) of the obtained snack products. Furthermore, the addition of DCC and the extrusion process resulted in a significant colour change, proportional to the amount of DCC. The extrusion process resulted in the increase of the water absorption index (WAI) and the water solubility index (WSI), whereas the addition of DCC did not influence the WAI significantly, and it decreased the WSI. The soluble and insoluble fibre content increased with the addition of DCC. The concluding remark is that DCC was successfully applied in the nutritional fortification of extruded snacks, serving as a good example for the development of new products.

Volatile organic compounds in honey are grouped into the chemical categories such as aldehyde, ketone, acid, alcohol, hydrocarbon, norisoprenoids, terpenes and benzene compounds and their derivatives, furan and pyran derivatives. They represent a fingerprint of a specific honey and therefore could significantly affect the quality of honey brandy. The aim of this research was to assess the impact of immobilized cell fermentation on volatile aroma of honey brandy. Aroma profile was determined using GC/FID and sensory analysis was conducted according to German DLG model. Results showed that immobilized cell technique gives honey brandies with lower ester contents, but significantly higher content of volatile organic compounds from honey.

Extrusion is the process which is used for the production of a wide range of final products (pasta, snacks, meat products, confectionery, etc.), as well as for modification of various types of flours in order to improve their properties. The aim of this study was to determine the effect of extrusion process on the properties of mixtures of barley flour and apple pomace. Mixture ratios (barley flour : apple pomace) used in this study were: 85 : 15, 70 : 30 and 55 : 45. Mixtures with 30 % moisture content were extruded at the temperature regime 70/90/110 °C. The research included determination of physical and rheological properties of non-extruded and extruded samples. It was found that with addition of apple pomace viscosity of extrudates decreased. Extrusion caused reduction of falling number. Increasing of apple pomace content in mixtures resulted in decrease of falling number. Sedimentation values were low both in non-extruded and extruded samples, probably due to low content of proteins in mixtures. Extrusion also resulted in increase of water absorption index. Dough stability was 0, due to lower quantity and poor quality of gluten. Extruded samples had higher farinograph quality number, which increased with increasing of apple pomace content.

Introduction. Brewer‘s spent grain (BSG) is the major by-product of the brewing industry, which is available in large quantities throughout the year, but its main application has been limited to animal feeding. BSG is a lignocellulosic material containing about 17% cellulose, 28% non-cellulosic polysaccharides, chiefly arabinoxylans, and 28% lignin. Because of that, it can be also serve as an attractive adjunct in human nutrition (3). The aim of this research was to investigate the potential of BSG application in production of value-added corn snack products. Materials and Methods. Corn grits used in this study was kindly provided by the mill Đakovo of the "Žito" Company Ltd. Osijek, produced in 2014. BSG was kindly provided by Osijek Brewery d.o.o., Osijek, (produced in 2013), and pectin by "Kandit" Ltd. Osijek. BSG was dehydrated in laboratory oven Memmert UFE 500 at 60°C, and milled at laboratory mill IKA MF10 with 2 mm sieve. Mixtures with 0, 5, 10 and 15% d. m. of added BSG were extruded in the laboratory single screw extruder (19/20 DN, Brabender, Germany) at following parameters: moisture content (15%), temperature profile (135/170/170°C), screw compression ratio (4:1), round die (4 mm), and 1% d. m. of added pectin with the aim of production of corn snack products. Obtained extrudates were air-dried overnight and milled in laboratory mill IKA MF10 with 1 mm sieve before the analysis. Chemical composition (standard ISO methods), resistant starch (RS) (1), total, soluble and insoluble dietary fibre (TDF, SDF and IDF) (2), total polyphenols content (TPC) and antioxidant activity (DPPH) (4) were determined. Results. The obtained results showed that the addition of BSG to corn grits caused significant increase of IDF content and slight increase of SDF and RS contents. Furthermore, products with BSG had a higher amounts of protein, ash and fat, and in accordance with this lower content of raw carbohydrates. Results for total polyphenols showed that the addition of BSG in corn grits proportionally increased their contents, but decreased antioxidant activity (DPPH). Conclusions. According to obtained results it can be concluded that the BSG as inexpensive by- product of brewering industry can be successfully incorporated in corn grits with the aim of production nutritionally more valuable corn snack products.

Introduction. Nowadays, a tendency for reducing food industry waste is becoming more prominent due to a growing interest for utilization of food industry by-products for various purposes. These by- products contain many potentially useful substances and they could become significant raw materials in the production/development of new products. Apricot kernels as by-products of processing are a valuable source of bioactive components like amygdalin, tocopherols, phenolic compounds and fatty acids. Some of them were studied in this research. Materials and Methods. Apricot kernels were obtained from Association of fruit brandy producers (Kneţevi vinogradi, Croatia). The initial oil content in apricot kernels was determined by Soxhlet extraction system using n-hexane as a solvent. Crude oil was obtained by cold pressing of apricot kernels on the laboratory screw press, and its oil quality parameters, namely, peroxide number, free fatty acids, moisture, insoluble impurities, iodine number and saponification number were determined. Furthermore, oil from apricot kernels was obtained also by supercritical CO2 (SC-CO2) extraction at pressure of 300 bar, temperature of 40°C and CO2 mass flow of 2 kg/h. The oil was collected every hour during extraction process (total extraction time was 5 hours). The oils obtained by screw pressing and with SC-CO2 were analysed for fatty acid composition, total tocopherols and amygdalin concentration. The apricot kernel extract was produced using 50% ethanol solution and was analysed for antioxidant and antibacterial activity, as well as amygdalin concentration. Antioxidant activity of extracts was determined by DPPH method. Antibacterial activity was conducted against four test bacteria strains: Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. It was assessed in terms of minimum inhibitory concentrations by a modified broth microdilution method. Fatty acid composition was determined by gas chromatography with flame ionization detector (GC-FID). Tocopherol concentrations were performed on reversed-phase High Performance Liquid Chromatography (HPLC) with fluorescence detection (FLD) and amygdalin concentration by HPLC with UV detection. Results. The initial oil content in apricot kernels was 49.60%, and moisture content 6.87%. The moisture content in crude cold pressed apricot kernel oil was 0.13%, peroxide number 0.49, free fatty acids 1.78, insoluble impurities 0.46%, iodine number 103.45, and saponification number 192.11. Concentration of total tocopherols during SC-CO2 extraction decreased from first collected fraction to the last, precisely from 2.52 mg/g of oil to 0.50 mg/g of oil. However, the concentration of total tocopherols in cold pressed apricot kernel oil was significantly lower (0.94 mg/g of oil) compared to SC-CO2 oil, while α-tocopherol was not detected. Fatty acid composition showed prevalence of palmitic, oleic (cis-9) and linoleic (cis-9, 12) acid, specifically 5.93%, 57.33% and 33.81% in all SC- CO2 extracts, which showed a great similarity to values of oil obtained by cold pressing.

Growing environmental concerns have created an urgent need to develop new biodegradable polymers or functional materials from combination of existing biodegradable polymers that have comparable properties with conventional polymeric materials at an equivalent cost [1]. This study focused on physical properties of binary and ternary blends polylactide (PLA), polycaprolactone (PCL) and thermoplastic starch (TPS). TPS was developed by plasticizing wheat starch with glycerol in the laboratory single screw extruder. Binary and ternary blends containing different compositions of PLA, PCL and TPS (with 30 mas. %) were prepared using a Brabender mixer. The miscibility of blends was investigated by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Mechanical analysis, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) were employed to study the mechanical properties and thermal stability of the blends. DSC analysis revealed that both PCL and TPS affected the PLA phase which resulting in an increase of its crystallinity. On the other hand, PLA acted as a nucleating agent [2] in PCL and, TPS restricted some level of mobility of PCL chains, reducing its crystallinity. When TPS, PCL and PLA were blended, there was a pronounced increasing in tensile strength and Young modulus compared to the neat TPS. The thermal stability of the blends was determined by TGA and insignificant influence was observed by adding the TPS. [1] V. Mittal, T. Akhtar, N. Matsko, Macromol. Mater. Eng. 300 (2015) 423. [2] V. B. Carmona, A. C. Corrêa, J. M. Marconcini, L. H. C. Mattoso, J. Polym. Environ. 23 (2015) 83.

Brewer’s spent grain (BSG) is the major by-product of the brewing industry, which contains about 17% cellulose, 28% non-cellulosic polysaccharides. It is available in large quantities throughout the year, but its main application has been limited to animal feeding. Nevertheless, due to its high content of protein and fibre (around 20 and 70% dry basis, respectively), it can also serve as an attractive adjunct in human nutrition. The aim of this research was to investigate the potential of BSG application in production of modified wheat flours by extrusion process [1-2]. Mixture ratios (wheat flour : BSG) investigated in this study were: 85 : 15, 70 : 30 and 55 : 45. Mixtures with 30 % moisture content were extruded in the laboratory single screw extruder at temperature profile 70/90/110 °C, using a screw with compression ratio 1:1 and die with 5 mm diameter. The research included determination of physical and rheological properties of non-extruded and extruded samples. The obtained results showed that the addition of BSG in wheat flour and extrusion process decreased all viscosity parameters. Furthermore, extrusion caused the reduction of falling number and sedimentation values, but the increment of water absorption index and dough development time. Dough stability for all extruded sample was 0, probably due to gluten “dilution” and degradation during the extrusion.

Extruded snack products are a popular product type among all consumers’ niches – from infants to elderly, since they are tasty and easy to consume regarding chewing and preparation. However, this is energy dense, nutritionally rather poor product category. Therefore, the aim of this research was to increase nutritional value of the extruded corn-based snacks with defatted Camelina sativa L. cake. Namely, Camelina sativa L. is valued for its oil, rich in omega-3-fatty acids. By-product of oil production is cake, rich in polyphenols, fibre and protein. Around 10 – 14 % of oil resides in the cake and may cause problems during extrusion due to low friction in barrel and fat oxidation. The residual oil was extracted from the cake by supercritical-CO2 extraction and defatted cake was obtained. Defatted Camelina sativa L. cake was added to corn grits in 3, 6 and 9 % d. m., 1 % pectin was added and mixture moisture was set to 15 %. Prepared samples were extruded in laboratory single screw extruder with 4 mm round die, screw with compression ratio of 4:1, at temperature profile: 135/170/170 °C. Obtained extrudates were air-dried and resistant starch content was determined according to AOAC 2002.02 method, starch damage according to AACC 76-31 and polyphenol content by Folin-Ciocalteau. Although extrusion resulted in significant decrease of resistant starch and polyphenol contents, resistant starch and polyphenol contents in extruded samples increased proportionally to addition of defatted Camelina sativa L. cake, while starch damage decreased. Defatted Camelina sativa L. cake was successfully applied in nutritional fortification of extruded snack, maximizing the utilization of the seeds and reducing the environmental impact of oil industry.

A growing trend in the food industry is the use of by-products. Using by-products of the food industry improves the nutritional value of new products while at the same time improves the utilization of these by-products and reduces overall waste. In this paper the effect of the addition of apple pomace in the amount of 45% on particle size distribution and chemical composition of corn snack products is examined. Addition of apple pomace significantly influenced the chemical composition of the snack product, reducing the proportion of protein (from 7, 36 to 4, 36) and increasing the proportion of fiber (from 3, 36 to 21, 65%) compared to snack product produced from only corn grits. Nutritional value of snack product is significantly improved with the apple pomace addition, while is not significantly influenced by the particle size.

Nusproizvodi prehrambene industrije predstavljaju jeftinu i lako dostupnu sirovinu sa velikim nutritivnim potencijalom. Podrijetlom iz različitih grana prehrambene industrije, mogu predstavljati značajan izvor proteina, prehrambenih vlakana i drugih biološki vrijednih komponenti, ali s druge strane često su nestabilni i skloni biorazgradnji. Ekstrudiranjem se značajno povećava njihova stabilnost, a time i mogućnost njihove implementacije u prehrambene proizvode. Zastupljenost keksa i srodnih proizvoda u strukturi dnevnog obroka omogućava da se promjenom njihovog sastava pojedine nutritivno vrijedne komponente uspješno uvedu u prehranu ljudi. Ipak, svaka promjena u sirovinskom sastavu neminovno utječe na kvalitetu proizvoda. Odstupanje od uobičajenog okusa, izgleda ili boje za danu vrstu proizvoda može rezultirati odbacivanjem proizvoda od strane potrošača i neuspjehom na tržištu. Dodatak pojedinih nusproizvoda prehrambene industrije u proizvodni proces ima za cilj povećanje nutritivne vrijednosti finalnih proizvoda, njihovu bolju valorizaciju u ekonomskom pogledu i smanjenje ukupnog otpada. U radu će biti dan pregled dosadašnjih rezultata istraživanja po pitanju fizikalno-kemijskih karakteristika ekstrudata kukuruzne krupice obogaćene pivskim tropom, pšeničnom klicom, izluženim repinim rezancima i tropom jabuke, a zatim i utjecaja zamjene dijela pšeničnog brašna navedenim dodacima na reološka svojstva tijesta i karakteristike tvrdog keksa i čajnog peciva (senzorska ocjena, tehnološka svojstva, nutritivna vrijednost).

Extruded snack products are one of the most popular snacks consumed all over the world.Usually they are not fortified with nutrients, but they can be very good source of nutrients, because of their prevalence.Consequently, the objective of this research was to increase nutritional value of the extruded corn-based snacks with defatted hemp (Cannabis sativa L.) cake. Hemp seeds contains 25 – 35% lipids, 20 – 25% protein and 20 – 30% carbohydrate, 10 – 15% insoluble fibers, and minerals.[1] In production of oil by cold pressing, cake is by-product rich in protein, fibre and polyphenols. Usually 10 – 14% of oil resides in cake and may cause problems during extrusion due to low friction in barrel and fat oxidation. The residual oil was extracted from the cake by supercritical-CO2 extraction and defatted cake was obtained. Defatted hemp cake was added to corn grits in 3, 6 and 9% d. m., 1% pectin was added and mixture moisture was set to 15%. Prepared samples were extruded in laboratory single screw extruder with 4 mm round die, screw with compression ratio of 4:1, at temperature profile: 135/170/170 °C. Obtained extrudates were air-dried and resistant starch content was determined according to AOAC 2002.02 method, [2] starch damage according to AACC 76-31, [3] polyphenol content by Folin-Ciocalteau, [4] antioxidant activity by DPPH radical scavenging activity[4] and soluble and insoluble dietary fiber according to AOAC 991.43.[5] Although extrusion resulted in decrease of resistant starch and polyphenol contents, resistant starch and polyphenol contents in extruded samples increased to addition of defatted hemp cake, while starch damage decreased. There was no significant difference between antioxidant activity of non- extruded and extruded samples, while it increase with addition of defatted hemp cake. Even extrusion resulted in decrease of fiber content, soluble, insoluble and total dietary fiber increased proportionally to addition of defatted hemp cake. Extruded snack products were successfully fortified with defatted hemp cake and it is well applied waste of oil industry. Since the hemp cake is rich in nutritional components, this can be a good example for development of new products.

Extruded snack products are one of the most popular snacks all over the world, since they are tasty and easy to consume regarding chewing and preparation. Because they are not nutritionally rich products, there is a challenge for food industry to improve them with various additives. Regarding to that, the aim of this research was to improve nutritional properties of corn snacks with defatted pumpkin cake. Defatted pumpkin (Cucurbita pepo L.) oilseed cake (DPC) was added to corn grits in 3, 6 and 9 % d. m., 1 % pectin was added with the aim to produce products with properties of ready-to-eat snacks, and mixture moisture was set to 15 %. Prepared samples were extruded in laboratory single screw extruder with 4 mm round die, screw with compression ratio of 4:1, at temperature profile: 135/170/170 °C. Obtained extrudates were air-dried and resistant starch content was determined according to AOAC 2002.02 method, starch damage according to AACC 76-31 and soluble and insoluble dietary fiber according to AOAC 991.43. The obtained results showed that addition of DPC did not have significant influence on resistant starch content. Starch damage content decreased with addition of DPC and content of soluble and insoluble fibers increased by the addition of DPC. Final conclusion is that the extruded corn snack products were successfully improved with DPC, which is rich in nutritional components, such as dietary fibers and proteins and that is a good example for development of new type of products, interesting for all age groups, from children to retirees.

Debljina i pretilost jedan su od javnozdravstvenih problema s kojima se učestalo susrećemo kako u liječničkim ordinacijama, tako i u svakodnevnom životu. U velikoj mjeri ovoj pojavi doprinose i loše prehrambene navike koje se usvajaju u najranijoj dječjoj dobi, poput grickanja snack proizvoda u međuobrocima, koji su kalorijski vrlo bogati, ali nutritivno siromašni. Visoki udio škroba i njegova brza probavljivost čine ove proizvode namirnicama visokog glikemijskog indeksa, a često sadrže i visoki udio soli. Istovremeno, ovi proizvodi gotovo da ne sadrže vlakna, vitamine i druge nutritivno važne sastojke. Kako bi se doskočilo ovom problemu od iznimne je važnosti promoviranje zdravih prehrambenih navika, kojima mogu doprinijeti i rješenja poput razvoja proizvoda sa smanjenom kalorijskom i/ili povećanom nutritivnom vrijednošću. Upravo je to jedan od ciljeva projekta „Primjena nusproizvoda prehrambene industrije u razvoju funkcionalnih i okolišno prihvatljivih ekstrudiranih proizvoda i dodataka“. U sklopu istraživanja na projektu, dodatkom nusproizvoda prehrambene industrije: pivskog i jabučnog tropa, izluženih repinih rezanaca i odmašćenih pogača od proizvodnje ulja, razvijena je paleta snack proizvoda na bazi kukuruzne krupice tipa flips kojima je smanjen glikemijski indeks, povećan udio vlakana i rezistentnog škroba, uz zadržavanje visokog stupnja prihvatljivosti od strane potrošača. Ovakvi proizvodi smanjene kalorijske vrijednosti, ali visokog osjećaja sitosti dobra su zamjena postojećim proizvodima na tržištu i imaju veliki potencijal komercijalizacije.

Snack products are one of the most popular products worldwide, tasty, easy to consume, but poor in nutritional quality. They can be directly (second generation / 2G) or indirectly expanded (third generation / 3G). The nutritional quality of the product may be increased by supplementation with different additives. One of them is hazelnut cake, a by-product of hazelnut oil production rich in proteins, fibres, and phenolic compounds. Defatted hazelnut cake was added to corn grits in ratios of 3, 6, and 9% d. m. The prepared samples were extruded in a laboratory single screw extruder. For the production of 3G snacks, supercritical CO2 (injection pressure: 140 bar) was added during the extrusion process, between the second and the third heating zone, which were at lower temperatures than for the production of 2G snacks. The obtained extrudates were air-dried, and then the 3G products were expanded by microwave heating. Resistant starch (RS) content was determined according to the AOAC 2002.02 method, the polyphenol content by the Folin- Ciocalteau, and soluble and insoluble dietary fibre according to AOAC 991.43. The contents of all three analyzed parameters increased with the addition of defatted hazelnut cake. 3G snacks had lower polyphenol content than 2G snacks, and a higher content of RS and soluble and insoluble dietary fibre. The obtained results show that hazelnut cake can be successfully applied in the production of nutritionally improved 2G and 3G corn snack products, and supercritical CO2 can be used for the production of 3G snacks.

Cocoa husk is by-product of chocolate production, made in roasting cocoa bean process. Since app. 10 % of the bean is husk, this is large environmental load if not further exploited. It is rich in fibre, protein, minerals, and polyphenols, contains theobromine and is potentially valuable raw material for food, cosmetic and pharmaceutical industries. The aim of this research was to investigate potential of cocoa husk application in enrichment of corn-based extruded products. It was added to corn grits in 5, 10 and 15 % d. m., moisture of mixtures was set to 15 % and prepared samples were extruded in laboratory single screw extruder at 135/170/170 °C, with 4 mm-round die and screw of compression ratio 4:1. Resistant starch (AOAC 2002.02), starch damage (AACC 76-31), polyphenol content (Folin- Ciocalteau) and antioxidant activity (DPPH) was determined. Resistant starch, polyphenol contents and antioxidant activity of extruded products increased proportionally to addition of cocoa husk, while starch damage slightly decreased, indicating that cocoa husk may be successfully employed as nutritional fortification agent.

Extrusion is a modern procedure for processing different types of raw materials and production of wide range of food products, where the corn grits are often used as main raw materials. Therefore the aim of this study was to determine the effect of screw configuration (4:1 and 1:1), moisture content (15% and 20%) and particle size of corn grits (>500 µm and

Studija okolišnih i bioloških uvjeta za razvoj optimalnih uzgojnih područja matice sive pčele proizašla je u okviru projektnih aktivnosti koje su se odvijale tijekom 2015. i 2016. godine u okviru projekta BEE Promoted – Promocija pčelarstva. Projekt je financiran u sklopu EU IPA prekograničnog programa Hrvatska – Bosna i Hercegovina (2007. - 2013.). Studija je pripremljena na osnovu prikupljenih, sistematiziranih i analiziranih podataka o potencijalima pčelarstva u tri područja: Zadar, Bihać i Posušje. Studija je podijeljena u 5 poglavlja i prikazuje potencijal proizvodnje pčelinjih proizvoda u navedenim područjima, zatim evaluaciju ljudskih i materijalnih resursa potrebnih za uzgoj matica, kao i SWOT analizu i pregled aktivnosti potrebnih za održivost i poboljšanje stanja pčelarstva u ispitivanom području.

Kurkuma (Curcuma longa) spada u porodicu Zingiberaceae i tradicionalno se stoljećima koristi u prehrani u Azijskim zemljama. Indija je najveći proizvođač, konzument i izvoznik kurkume. Njezin gomolj sušen i samljeven koristi se širom svijeta kao začin (najpoznatiji začin čiji je glavni sastojak kurkume je curry) i kao aditiv mnogim proizvodima kojima je potrebna intenzivna žuta boja koja je zdravstveno prihvatljiva. Najznačajniji sastavni dio gomolja kurkume je grupa bioflavonoida tj. kurkumini (kurkumin (77 %), demetoksikurkumin i bis-demetoksikurkumin). Kurkumin se izolira metodom ekstrakcije organskim otapalima, najčešće etanolom uz upotrebu Soxhleta, ultrazvučnom i mikrovalnom ekstrakcijom, a u novije vrijeme zbog povećane upotrebe u prehrambene svrhe (dodaci prehrani) kao otapalo koristi se triacilglicerol. Kurkumin posjeduje značajna protuupalna, antioksidativna, kemoprotektivna, antikancerogena i gastroprotektivna svojstva, djeluje na neurosistem i jedan je od najistraživanijih bioflavonoida današnjice. Cilj ovog rada je prikazati dobrobiti kurkume i kurkumina u prehrani i zdravlju ljudi i životinja.

Micetizam (trovanje gljivama) predstavlja čest oblik intoksikacije hranom, kako u svijetu tako i u našoj zemlji. Od 5 000 vrsta viših gljiva, koliko ih raste u Europi, smatra se da je samo 60 vrsta otrovno, od čega je 7 smrtonosno. Premda je broj otrovnih vrsta relativno malen, statistike pokazuju da u Europi godišnje ima oko 10 000 slučajeva otrovanja, od čega mnogo smrtnih slučajeva. Najznačajnije vrste otrovnih gljiva u Republici Hrvatskoj su: zelena pupavka (Amanita phalloides), otrovna zavodnica (Omphalotus olearius), muhara (Amanita muscaria), crvenjača (Cortinarius orellanus), bljuvara (Russula emetica), ludara (Boletus satanas), panterova muhara (Amanita pantherina), zelenkasta vitezovka (Tricholoma flavovirens) i žućkasta pupavka (Amanita citrina). S obzirom na duljinu latencije i tip kliničkog sindroma micetizam se dijeli na micetizam s kratkom latencijom i micetizam s dugom latencijom. Prvi karakterizira pojava simptoma 1 – 4 sata nakon ingestije otrovnih gljiva, pri čemu dominiraju simptomi od strane gastrointestinalnog sustava (mučnina, povraćanje, abdominalni bolovi, dijareja i dr.), a u pravilu ima dobru prognozu. Drugi karakterizira pojava simptoma vezanih uz teško oštećenje jetre i bubrega (žutica, ascites, grčevi mišića, vrtoglavica, halucinacije, oskudno mokrenje i dr.), obično nakon 5, 12, 24 i više sati od ingestije otrovnih gljiva i u pravilu ima lošu prognozu, često i smrtni ishod. Potrebno je naglasiti kako kod micetizma nema specifičnog protuotrova za bilo koju vrstu otrovne gljive, nego samo suportivna terapija. Cilj ovog rada je ukazati na veliku učestalost i problem micetizma u kliničkoj praksi te povećati svijest ljudi o važnosti dobrog poznavanja gljiva prilikom branja, kao i pravilnog skladištenja, pripreme i konzumacije jestivih gljiva.

Poremećaj ravnoteže u organizmu između proizvodnje reaktivnih kisikovih radikala (ROS) i antioksidansa nazivamo oksidacijskim stresom. Do pomaka ravnoteže dolazi ukoliko je smanjena antioksidacijska obrana organizma ili ako je povećano stvaranje slobodnih radikala. Antioksidansi su sve one tvari koje u maloj količini u kratkome vremenu neutraliziraju djelovanje slobodnih radikala i drugih oksidansa. Oni nastaju u stanici ili se u organizam unose hranom ili u obliku dodataka. Antioksidansi onemogućuju stvaranje slobodnih radikala u organizmu, uništavaju stvorene slobodne radikale ili popravljaju oštećenja u stanici nastala djelovanjem slobodnih radikala.U radu su prikazani biomarkeri oksidacijskog stresa u ljudi i životinja, prema podjeli na enzimske, neenzimske, te ostale biomarkere s naglaskom na biomarkere umora perifernih mišića. Biomarkeri umora perifernih mišića u ljudi i životinja su markeri staničnog mišićnog oštećenja i pokazatelji mišićnog stresa, a koriste se za uvid u mehanizme iscrpljenosti tijekom vježbanja kako bi se otkrio povećani umor ili se otkrili manjkavi metabolički putevi. Utvrđivanje oksidacijskog stresa važno je zbog mogućnosti pravovremenog uključivanja antioksidacijskih tvari koji povećavaju antioksidacijski kapacitet ljudskog i životinjskog organizma.

Brewer's spent grain (BSG) is a by-product generated after the production of bear. This by-product is rich source of dietary fiber and proteins, and has potential to increase nutritional value of cookies. This paper examines the influence of fresh, no-dried and no-milled brewer's spent grain addition (15, 25 and 50%) on sensory characteristics, instrumental parameters of color (CIE L*, CIE a* and CIE b*), microbial stability (according to ISO standards) and fiber and protein content of cookies (according to AOAC methods). Addition of BSG decreased L* and b* values, while a* values increased. Protein content of cookies increased from 7.55oh to 9.69%, and fiber content from 6.8 to 15.55%. Surface appearance, hardness, grittiness and flavor of cookies with addition of 25% of BSG were the best compared to those of cookies with 15 and 50% BSG addition. ln fresh BSG, Enferobacteriaceae were detected (40 cfu/g), while in all final products, cookie samples, Enterobacteriaceae, E. coli, Clostridium spp., yeasts and molds were not detected. The results have shown that fresh, no-dried and no-milled BSC increased nutritional value of cookies without negative influence on cookie sensory characteristics and microbiological stability.

Med predstavlja vrlo složen sustav koji zauzima posebno mjesto u različitim kulturama u povijesti čovječanstva gdje je korišten kao hrana i kao lijek. Sastav i svojstva meda ovise o brojnim čimbenicima, prije svega o biljnim vrstama, klimatskim uvjetima, uvjetima okoliša i dr., a općenito ga čine ugljikohidrati, voda, proteini, aminokiseline, enzimi, vitamini, minerali, tvari arome i brojne druge tvari u manjim udjelima. Upravo tvari koje pčele svojom aktivnošću unose u med i koje se u medu nalaze u relativno malim udjelima čine med posebnim i vrijednim proizvodom. Med, kao uostalom i brojni drugi prehrambeni proizvodi, zbog cijene ali i zbog dostupnosti, odnosno povećanom potražnjom, podložni su patvorenju. Za patvorenje meda danas se koriste različita sredstva, ali najčešće se spominju invertni šećer, škrobni sirupi, saharoza, melasa i slično, zbog sličnosti nekim svojstvima, dostupnosti i cijeni. Osim toga, na tržištu se pojavljuje i na druge načine patvoren med, što predstavlja problem kako kupcima tako i proizvođačima meda. Danas su u cilju utvrđivanja patvorenja hrane, time i meda, razvijene brojne metode. Cilj ovoga rada je ukazati na najčešće metode patvorenja meda i dati pregled metoda koje se koriste za utvrđivanje patvorenja.

Corn grits is main raw material for production of numerous extrudates (snacks, breakfast cereals, etc.). In order to increase nutritive value of extruded products, different type of food industry by-products have been recently used. Namely, these inexpensive materials are good source of dietary fibres, proteins, polyphenols and other valuable nutrients. However, during the extrusion process higher amount of fibres, proteins and oils could reduce expansion, which results in poor physical properties of products. In this study possibility of pectin addition (0.5 and 1% d.m.) with the aim of resolving the problem of poor expansion and textural properties in corn extrudates enriched with brewer's spent grain (BSG) and sugar beet pulp (SBP) (5, 10 and 15% of added by-products) was investigated. Samples were produced in the laboratory single screw extruder at following parameters: temperature profile (135/170/170 °C), screw compression ratio (4:1), round die (4 mm) and moisture content (15%). Obtained extrudates were air-dried overnight, and expansion ratio (ER), bulk density (BD), hardness and fracturability were determined. The obtained results show that the addition of by-products decreased expansion ratio and fracturability, but increased hardness and bulk density of extrudates. On the other hand, pectin addition resolved the problem of poor expansion and textural properties in extrudates with by-products. In extrudates with SBP good results were obtained when pectin was added in amount of 0.5%, but in extrudates with BSG satisfactory results were obtained with 1% of pectin. In conclusion, pectin can be used successfully in production of corn extrudates enriched with BSG and SBP, with the aim of resolving the problem of poor physical properties in these extrudates.

By-products of plant food processing, which are rich in fibre and bioactive compounds, have attracted much attention for their functionality and potential as food ingredients in recent years. Extrusion, as a continuous process with high versatility and productivity, offers a good avenue to incorporate different types of by-products in ready-to-eat snacks and breakfast cereals. In addition, incorporating of these by-products can improve nutritional value of extruded products that are otherwise carbohydrate-rich, high glycaemic products. The aim of this study was to investigate the possibility of application brewer’s spent grain (BSG), sugar beet pulp (SBP) and apple pomace (AP) in production of corn snack products. By-products were mixed with corn grits at different ratios (0/100 ; 5/95 ; 10/90 and 15/85), where in the mixtures with BSG and SBP pectin was added at level 1% d. m., with the aim to produce products with properties of ready-to-eat snacks. Prepared samples with 15% of moisture content were extruded in the laboratory single screw extruder at temperature profile 135/170/170 °C, using a screw with compression ratio 4:1 and die with 4 mm diameter. Obtained extrudates were air-dried overnight, and physical and sensory properties of extrudates were determined. The obtained results showed that addition of by-products to corn grits resulted in decrease of expansion ratio (ER) and fracturability, whereas bulk density (BD) and hardness of extrudates increased. Acceptable scores in sensory evaluation received all samples with brewer's spent grain and sugar beet pulp (with addition of 1% pectin), and samples with 5 and 10% of apple pomace. It can be concluded that these three by-products can be successfully incorporated in corn grits with the aim of production acceptable expanded corn snack products.

Extrusion is one of the most significant processes in food industry, where corn grits is often used as main raw material. In order to increase nutritive value and improve physical and chemical properties, in corn grits can be added flours of different grains, dehydrated fruits and vegetables, etc. Cocoa shell as a by-product of cocoa beans processing is a significant problem in the food industry. Since it is a good source of dietary fiber and polyphenols, it could be used as raw material for development of new products. Therefore, the aim of this study was to investigate the influence of extrusion process and cocoa shell addition (in proportions of 5%, 10% and 15%) on properties of extrudates based on corn grits. On obtained extrudates physical properties were determined, which included: expansion ratio, bulk density, texture, color, water absorption index and water solubility index. It was established that addition of cocoa shell resulted in decrease of expansion ratio and fracturability, but in increase of bulk density and hardness of extrudates. Extrusion caused lightening of control sample of corn grits, but darkening of extrudates with added cocoa shell. Water absorption index and water solubility index increased significantly after extrusion. From all above it can be concluded that cocoa shell can be successfully added to corn grits in order to produce new extruded products.