Grape seeds are one of the most accessible by-products of the wine industry in large quantities (about 2.4 million t/year). Numerous researchers have shown that grape seeds have a high potential for use as a functional ingredient in the food industry due to their high content of protein, fiber, minerals, and polyphenols. The aim of the paper is to evaluate the possibilities of using grape seed flour (GSF) in the bakery industry from both chemical and rheological points of view. Research shows that grape seed flour contains about 42 times more fiber than wheat flour and approximately 9 times more calcium, 8 times more magnesium, and 2 times more potassium. To assess this potential, four samples of bread from flour mixtures with 3%, 5%, 7%, and 9% (w/w) degree of replacement with GSF were prepared, analyzed, and compared with a control sample from 100% wheat flour. From a rheological point of view, the baking qualities deteriorate: the water absorption capacity (CH) decreases from 58.2% to 55.8%, the dough stability increases from 8.50 min to 9.83 min, the α slope varies from −0.066 Nm/min to −0.104 Nm/min, the β slope increases from 0.576 Nm/min to 0.630 Nm/min, and the γ slope varies from −0.100 Nm/min to −0.198 Nm/min. The sensory analyses performed by the panel of evaluators enclosed the sensorial characteristics of the samples with 3% and 5% GSF between the two control samples made from flour types 480 and 1250. The conclusions show that the sample containing 7% and 9% are unsatisfactory from rheological and sensorial points of view and the samples with 3% and 5% can be considered a fiber source and a Cu source, respectively, and are rich in Zn.

Pumpkin (Cucurbita maxima) seeds are a rich source of ingredients such as aminoacids, fatty acids, minerals, and phytochemicals exhibiting nutraceutical effects on human health. In this work, partially defatted pumpkin seeds flour, a by-product obtained during the manufacture of pumpkin seeds oil, was studied as an additive for common wheat flour. We explored the physico-chemical properties as well the content in amino acids of the partially defatted pumpkin seeds. The obtained results revealed that partially defatted pumpkin seeds are a good source of protein (42.75% d.m.), lipids (12.28% d.m.), total carbohydrates (37.4% d.m.), from which crude fiber (26.64% d.m.). This by-product presents a high mineral content (mg/100g): potassium (1290), magnesium (693), iron (87.8), zinc (11.5) and copper (2.49).The partially defatted pumpkin seeds proteins contain significant amounts of essential amino acids such as valine, histidine, isoleucine, leucine, threonine and methionine.

Grape skin is considered a valuable by-product for antioxidant and antibacterial agent preparation. The grape skin contains some active compounds, such as, dietary fiber, polyphenols, flavonols, and resveratrol; it is commonly used as a nutritional supplement. The main aim of this study was to establish the optimum dose of grape skin flour, to be used as a functional ingredient in the bakery products industry, from both chemical and rheological point of view. The laboratory experiments evaluated the functional potential of wheat flour enriched with grape skin flour, in different proportions, by examining the chemical composition and rheological behaviour of the doughs. Protein, crude fibre, fat, ash and mineral contents were determined. Using �H-NMR spectral technique, the fatty acids composition was determined, especially the concentrations of short-chain saturated fatty acids (C4-C8), di-unsaturated fatty acids, mono-unsaturated fatty acids and long-chain saturated fatty acids (]C8). 1H-NMR spectra were recorded on a Bruker Ascend 400 MHz spectrometer. The rheological behaviour was analyzed using the predefined Chopin + protocol on Mixolab, an equipment of CHOPIN Technologies. Grape skin flour was incorporated into wheat flour at three different levels, 5, 10 and 15% and it was found that incorporation up to a 15% level into the formulation of wheat flour yielded an acceptable product in terms of rheological parameters, with improved chemical, nutritional and functional properties.

The information from this study may provide opportunities for industrial application of sorghum seed flour as a useful bakery ingredient and a suitable alternative source of functional compounds to whole wheat flour. The chemical composition of sorghum was evaluated compared to that of wheat whole flour, showing high contents of mineral and fibers. Next were evaluated the dough rheological properties of flour mixtures using Mixolab equipment, “Chopin+” protocol. Finally, six bread samples were obtained from wheat flour with addition of sorghum seed flour in various percentages, in which three samples were fortified with Lactobacillus plantarum compared to the other three bread samples without the addition of any lactic acid bacteria. All six bread sample were compared to a control bread sample with wheat flour type 550. The results show the fat and raw fiber were higher in sorghum compared to whole wheat flour. Also, the content of magnesium, potassium, and iron were much higher than in whole wheat flour. A significant improvement of the sensorial characteristics was observed in bread samples in which lactic acid bacteria was used.

The by-product resulting from the production of the sea-buckthorn (Hippophae rhamnoides) juice may be a functional food ingredient, being a valuable source of bioactive compounds, such as polyphenols, flavonoids, minerals, and fatty acids. For checking this hypothesis, two extracts were obtained by two different methods using 50% ethyl alcohol solvent, namely through maceration–recirculation (E-SBM) and through ultrasound extraction (E-SBUS), followed by concentration. Next, sea-buckthorn waste (SB sample), extracts (E-SBM and E-SBUS samples) and the residues obtained from the extractions (R-SBM and R-SBUS samples) were characterized for the total polyphenols, flavonoid content, antioxidant capacity, mineral contents, and fatty acids profile. The results show that polyphenols and flavonoids were extracted better by the ultrasound process than the other methods. Additionally, the antioxidant activity of the E-SBUS sample was 91% higher (expressed in Trolox equivalents) and approximately 45% higher (expressed in Fe2+ equivalents) than that of the E-SBM sample. Regarding the extraction of minerals, it was found that both concentrated extracts had almost 25% of the RDI value of K and Mg, and also that the content of Zn, Mn, and Fe is significant. Additionally, it was found that the residues (R-SBM and R-SBUS) contain important quantities of Zn, Cu, Mn, Ca, and Fe. The general conclusion is that using the ultrasound extraction method, followed by a process of concentrating the extract, a superior recovery of sea-buckthorn by-product resulting from the juice extraction can be achieved.