Search

Sunflower meal (SFM), a byproduct of sunflower oil extraction, is a relatively inexpensive protein source with high potential for feed formulations. Dry fractionation methodologies are emerging as 'green' and affordable technologies with the potential to additionally enhance the nutritional quality of plant-based raw materials for animal feed, including sunflower meal. Following the optimization of a dry fractionation process in a previous study of the authors, this research aims to validate the defined parameters through the processing of three sunflower meals (SFM1, SFM2, and SFM3) with different characteristics. The dry fractionation process includes two-stage grinding using hammer mill and roll mill and fractionation of sunflower meal by sieving. The process successfully increased the protein content of sunflower meals in the range of 17.5% to 31.2%, reaching levels high enough to be categorized as "high protein" sunflower meals of first quality (42% as is). Exceptionally high fraction yields (76.5–78.9%) were obtained for all three sunflower meals. The lowest energy consumption was recorded for SFM1 (8.44 Wh/kg), while slightly higher values were observed during the processing of SFM2 and SFM3 (9.30 and 9.93 Wh/kg, respectively). Relative amino acid enrichments ranging from 13.35% to 26.64% were achieved, with lysine enrichment ranging from 18.9% to 36% and methionine from 30.6% to 44.1%. [ABSTRACT FROM AUTHOR]

Damaged starch typically arises from mechanical damage caused by the action of the roller mills during the wheat flour milling process. The content of resulting damaged starch in the flour significantly influences its characteristics, emphasizing the importance of understanding and controlling the formation of damaged starch for the production of specialized flours. A detailed passage analysis from three different commercial mills revealed that starch damage control is primarily achievable at front passages of the sizing and reduction system, which generate the majority of the flour release in the mill. Also, it revealed that damaged starch content increases progressively from the initial to the final passages during milling in the break, sizing and reduction system. To investigate the effects of milling parameters on damaged starch, flour yield, and energy consumption, a three-level and three-variable Box–Behnken experimental design with response surface methodology was applied. As independent variables roll gap (0.05–0.35 mm), feed rate (0.15–0.35 kg/cm min), and fast roll speed (400–800 rpm) were employed. The obtained models were utilized to optimize milling conditions for producing flours with special characteristics. [ABSTRACT FROM AUTHOR]

A method based on the reverse breakage matrix approach is proposed for controlling the effects that milling has on the particle size distribution and composition of the comminuted material. Applicability, possibilities, and limitations of the proposed method are tested on examples related to the process of wheat flour milling. It has been shown that the reverse matrix approach can be successfully used for defining the particle size distribution of the input material leading to the desired, predetermined particle size and compositional distribution in the output material. Moreover, we have illustrated that it is possible to simultaneously control both, input and output particle size distribution, together with the composition of the output material.

Sunflower meal, a by-product of oil extraction from sunflower seeds, is an important protein source in domestic as well as European feed industry. There is a common interest for the proper utilization of sunflower meal and for the development of an effective fractionation process in order to obtain a nutritionally improved sunflower meal. This paper proposes and compares two dry fractionation processes for the improvement of sunflower meal protein content on a laboratory scale. The first phase of both processes included two step milling using a hammer and roller mill. In the second phase, the ground sunflower meal was fractionated by sieving or by air classification. Results indicated that the implementation of any of the suggested processes improved protein content of the starting sunflower meal to a level sufficient to categorize it as "high-protein" according to current national regulation on animal feed quality, with the fraction yields over 50%. For the air classification process the most promising result was achieved for air flow of 7 m3 /h (12.8% relative protein enrichment, 56.42% fraction yield). For the fractionation process with sieving as a separation step, when fractions smaller than 350 µm were conjoined, relative protein enrichment of 28.5% and fraction yield of 51.17% were achieved. The high protein content (48.81% on dry basis) of the joined fraction enables enough space for optimizing the protein content - fraction yield ratio of obtained sunflower meal. By applying sieves with larger aperture, it is possible to obtain higher yields of sunflower meal categorized as high-protein on account of a slight decrease in protein content, which gives this process a certain flexibility and potential for application on a larger scale.

Brewer's spent grain (BSG) is a by-product generated during the brewing process. It is a rich source of dietary fibre and proteins, with great potential to increase nutritional value of food products. In this research different quantities of fresh (non-dried and non-milled) brewer's spent grain (15, 25 and 50%) were added to wheat flour on a replacement basis in order to evaluate its effect on fibre and protein content, instrumental parameters of colour, microbial stability and sensory characteristics of cookies. Protein and fibre content of cookies increased following the addition of BSG from 7.55% to 9.69% and 6.8 to 15.55%, respectively. Considering the colour characteristics, addition of BSG decreased L*and b* values, while a*values increased. Enterobacteriaceae, Escherichia coli, Clostridium spp., yeasts and moulds were not detected in cookie samples, while the Enterobacteriaceae were detected (40 cfu/g) in fresh BSG. The addition of 25% of BSG resulted in best sensory characteristics of cookies in terms of surface appearance, hardness, grittiness and flavour. The results have shown that fresh BSG has a potential to increase nutritional value of the cookies without negative influence on cookie sensory characteristics and microbiological stability.

Roller mills are one of the most frequently used grinding machines especially for cereal milling. Magnitude and type of the forces acting on particle depend on the set of roll parameters. Particle size distribution (PSD) resulting from milling a particular feed size critically depends on the ratio of roll-gap to input particle size. Box-Behnken experimental design was applied in order to optimize roll-gap adjustments and desired PSD of the milling output obtained by subsequent grinding of wheat on three pair of rollers. Adequate models, which allow the optimization of the milling process, were obtained by regression analysis. Values that define the PSD of the output, i.e. weight fractions of the milling output size fractions, were set to minimum, maximum or values within a certain interval. The examples of optimization which set the roll-gap values to ensure the desired PSD of the output, were obtained with a high level of desirability.

Summary: Sunflower meal, as a high protein source, is usually utilised in animal feed, but other means of valorisation of this byproduct should be investigated in order to increase sunflower meal industrial functionality and therefore economic value. High protein content could suggest potential ability to stabilise food emulsions. Current study investigated the influence of sunflower meal protein content and particle size distribution in stabilisation of oil‐in‐water emulsions. Sunflower meal samples were characterised in terms of chemical and amino acid content and FTIR spectroscopy, while in the obtained emulsion samples creaming index, droplet size, droplet size distribution and zeta potential were determined. A relatively equal distribution of hydrophilic/hydrophobic amino acids (46% and 54%, respectively) was determined indicating a strong amphiphilic character of proteins and potentially effective emulsion‐stabilising properties. Further results suggested a positive influence of higher protein content (increasing from 16.78% to 42.56%) on lower creaming index values (lowering values from 84% to 32%, respectively). Protein content and particle size distribution strongly affected emulsion droplets sizes (ranging from 77.32 to 238.61 μm) and zeta potential values. Therefore, the evaluation of the obtained results suggested that high protein sunflower meal can be applied for the stabilisation of oil‐in‐water emulsions. [ABSTRACT FROM AUTHOR]

Optimization of bread dough formulation with defatted wheat germ (DWG) in terms of dough rheological properties was the objective of this study. Fractional factorial design 2 V 5 − 1 was applied in order to investigate influence of DWG granulation (<150 µm and 150−1000 µm), DWG content (10 and 20%), addition of gluten (0 and 5%), ascorbic acid (0.004 and 0.008%) and combined improver (0.1 and 0.3%) on farinograph and extensograph parameters. Responsive variables were water absorption and the degree of softening, obtained by farinograph, and resistance to extension and extensibility as well as their ratio, obtained by extensograph analysis. Gluten addition expressed dominant positive effect on water absorption and the degree of softening. The most pronounced negative effect on dough resistance exhibited DWG content (contribution of 57%). The combination of DWG with smaller particle size and 5% of gluten addition increased both resistance and extensibility, but R/E ratio was not affected. The optimal values for DWG granulation, DWG content, gluten content, ascorbic acid content and combined improver content were: < 150 µm, 14.24%, 4.83%, 0.004% and 0.1%, respectively, while predicted values for desired responsible variables were: water absorption 65.90%, degree of softening 84.05 FU, resistance 301.30 EU, extensibility 108.55 mm and R/E 2.5. [ABSTRACT FROM AUTHOR]

The goal of this study was application of conventional [Soxhlet (SOX)] versus novel [supercritical fluid (SFE), microwave-assisted (MAE) and ultrasound-assisted (UAE)] extraction techniques for wheat germ oil recovery. Even though results suggested that MAE (with methylene chloride) provided the higher polyunsaturated fatty acids yield and higher oil functional quality comparing to SFE, SOX and UAE, all obtained oils exhibited good fatty acid profile and functional quality. SFE was the most suitable technique for oil recovery as provided certain advantages comparing to all other extraction techniques due to generally similar or higher tocopherol content, antioxidant activity and absence of organic solvent residues. [ABSTRACT FROM AUTHOR]

BACKGROUND The breakage matrix approach is a mathematical tool to relate input and output particle size distribution from a milling operation. Adjustment of the break release in the flour milling process is extremely important because it affects granulation and quality characteristics of the stock and hence the total results and balance of the mill. In this study the breakage matrix approach has been used for the purpose of controlling the release on the front passages of the break system in the flour milling process. RESULTS It has been established that, for any particle size distribution of wheat, it is possible to predict break releases together with the distribution of the release size fractions by using the breakage matrices. Also, the reversibility of this approach is examined, that is the possibility to identify the wheat particle size distribution that would result in desired break releases and/or the desired yields of different sized intermediate stocks under the given set of milling conditions. CONCLUSION It is confirmed that the breakage matrix approach can be successfully used to predict the break releases. The reverse breakage matrix concept allows the determination of the wheat particle size distribution which would result in a targeted break release. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]