Comparative study on the physico-chemical, textural and thermal properties of instant porridges based on spelt and oats

Changing of food habits and increased preference for healthy meals, along with the growth of breakfast industry has increased the size of 'ready-made' and instant porridge market in Serbia. Porridges dominantly marketed are those based on oats. However, there is a growing interest of local producers to use other cereals for porridge production. Therefore, this work was aimed to estimate the porridge-making ability of spelt wheat (Triticum aestivum spp. spelta) in comparison to that of oats. The studied porridges are instant products, based on extruded spelt or oat flour. The proximate composition, hydration properties (water absorption index-WAI and water solubility index-WSI), consistency and thermal properties were determined with the aim to compare the characteristics of the porridges. In general, the spelt-based porridge had more total and insoluble fibres, proteins, minerals and less available carbohydrates in comparison to the oat porridge. The spelt porridge may be eligible to bear the nutritional claim 'high-fibre' which is advantageous for the market viability of the product. Both porridges had >20% of damaged starch due to high initial content in the flours and extrusion processing of flours, though spelt-based extrudate and porridge were significantly higher in this parameter. Oat-based extrudate and porridge were higher in resistant starch content. The consistency was similar between the porridges, although spelt tended to form slightly firmer and cohesive porridge. Spelt porridge had better hydration properties (higher WAI) which are a featured attribute for this kind of product, similarly to higher consistency values. Spelt wheat, in its extruded form, is a suitable ingredient for porridge production

Influence of different extrusion temperatures on the stability of ellagic acid from raspberry seeds

Production of raspberry products leaves large amounts of seeds which are considered as by-product or waste. These seeds are rich source of ellagic acid and about 88% of the total ellagic acid content in raspberries comes from the seeds. This study investigates the influence of extrusion process at different temperatures on the content of ellagic acid in 'Willamette' raspberry seeds. The extrusion was performed on a Brabender singlescrew laboratory extruder and at three temperature regimes: 140, 160 and 200°C. HPLC/DAD analysis was used to determine and quantify the content of ellagic acid in the extruded samples. Ellagic acid content was quantified by calculation using a calibration curve established from standard ellagic acid. The content of ellagic acid in raspberry seeds was found to be 286.54 μg/g. Use of different extrusion temperatures did not have any impact on the stability of ellagic acid from 'Willamete' raspberry seeds, i.e. did not make significant differences in the content of the ellagic acid. These findings indicated that raspberry seeds may be suitable for the high temperature food processing

Comparison between Organic and Conventional Spelt and Wheatgrass juice

This work is aimed to compare antioxidant and scavenger properties of conventionally and organically produced speltgrass. Moreover, the antioxidant status of spelt was compared with wheatgrass. Three spelt varieties were analyzed:Nirvana, Ebners–Rotkorn variety and Eco-10. Antioxidant enzymes, superoxide-dismutase and guiacol-peroxidase, were determined as well as ferric reducing antioxidant power and DPPH-antiradical power. Total soluble proteins and total phenols were determined and also lipid peroxidation as a parameter of oxidative stress. The organically produced spelt was exposed to the higher levels of oxidative stress than conventionally produced spelt, and also DPPH antiradical power was induced by conventional production, which is also demonstrated using the relative antioxidant capacity index. The best antioxidant properties, better than wheat, showed organically produced spelt genotype Ebners–Rotkorn which is determined by the highest phenol content, superoxide-dismutase activity, DPPH antiradical power and ferric reduced antioxidant power and consequently with the lowest lipid peroxidation intensity

Kinetics and optimization of biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing plant

A low-cost, highly active CaO-based catalyst was prepared from waste filter cake (WFC) from a sugar beet processing factory by calcination in air at 900 °C for 2 h, referred to as the calcined filter cake (CFC). It was used to catalyze the rapeseed oil transesterification with methanol under mild reaction conditions (methanol-to-oil molar ratio of 9:1, catalyst loading of 4–10 %, and reaction temperature of 40–60 °C). Rapeseed oil was characterized regarding the physicochemical properties and fatty acid profile. Low free fatty acid content (about 2.0 mg KOH/g) allowed the direct use of the base CFC catalyst for rapeseed oil transesterification. Rapeseed oil has more unsaturated fatty acids (about 93 %), with oleic acid as the most abundant, than saturated fatty acids (about 7 %). A simplified model combining the changing mechanism of the reaction and the triacylglycerols mass transfer limitation successfully describes the kinetics of transesterification. A good agreement between the model and the experiment was proved by the mean relative percentage deviation for the conversion degree of only ± 7.43 % (based on 42 data). The apparent reaction rate constant follows the Arrhenius equation with the activation energy of 51.9 kJ mol−1. The FAME content higher than 96.5 % can be obtained in wide ranges of the catalyst amount (4–10 %) and the reaction time (about 45–70 min). The following conditions were optimum: the reaction temperature of 59.2 °C, the catalyst loading of 9.1 % (based on the oil weight), and the reaction time of 47 min

Biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing

A solid catalyst was prepared from waste filter cake (WFC) from a sugar beet processing plant and used, after calcination at 900 °C within 2 h, for biodiesel production from rapeseed oil and methanol. The calcined WFC (CFC) catalyst was characterized by XRF, FTIR, XRD, TGA/DTG, TPDe, TPD-CO2, SEM, N2 physisorption, and Hg porosimetry. The CFC is a CaO-based catalyst with a rigid, sustainable macroporous structure with the largest particles of 2.0 × 0.5 µm, a specific surface area of 7.3 m2/g, and a basicity of 0.27 mmol/g. It provides high conversion of 97.9% in 1 h at the methanol-to-oil molar ratio of 9:1, the temperature of 60 °C, and the catalyst loading of 10% of the oil mass. Its catalytic efficiency is comparable to the WFC-based nanocatalysts and CaO-based catalysts from natural sources. CFC was reused twice with a negligible decrease in catalytic activity, ensuring a FAME content above 97% in 1 h. The biodiesel produced from rapeseed oil over the CFC catalyst has good fuel properties that fulfill most of EN 14214. Therefore, WFC is a promising source of a low-cost, highly active, basic, and environmentally friendly CFC catalyst, which could reduce biodiesel production costs. From this point of view, this catalyst has great potential for developing the process at the commercial level