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BackgroundDespite their reliability- and validity-related challenges, self-reports remain the most common data collection method in nutrition research, food-related consumer and marketing research. The rapid development of technology has nevertheless inspired attempts to overcome the challenges of self-reports by applying technological solutions capable of capturing objective data.Scope and approachWe reviewed objective measurement technologies applicable in nutrition research, food-related consumer and marketing research, spanning the continuum from food-evoked emotions to food choice and dietary intake. Focusing on non-invasive solutions, we categorised identified technologies according to five study domains: 1) detecting food-related emotions, 2) monitoring food choices, 3) detecting eating actions, 4) identifying the type of food consumed, and 5) estimating the amount of food consumed. Additionally, we considered technologies not yet applied in the targeted research disciplines but worth considering in future research.Key findings and conclusionsWithin each domain, several variables have been measured using diverse technologies or combinations of technologies. These technologies cover wearable and remotely applied solutions that collect data on the individual or provide indirect information on consumers’ food choices or dietary intake. The key challenges of the reviewed technologies concern their applicability in real-world settings; capabilities to produce accurate, reliable, and meaningful data with reasonable resources; participant burden, and privacy protection. We provide recommendations for researchers and practitioners in nutrition research, food-related consumer and marketing research to work around the key challenges. For fruitful use of available technologies, we encourage collaboration between technology developers and experts in nutrition, consumer, and marketing sciences.

Rapeseed press cake was upcycled as a protein-enriched ingredient through dry fractionation. The protein-enriched fraction contained higher amounts of phytic acid compared to press cake, and phytase treatment was applied to decrease the phytic acid content from 6.8 to 0.5%. The effect of phytase treatment leading to the release of cations was also mimicked by extrinsic calcium addition. Both phytase treatment and calcium addition significantly improved the heat-induced gel properties but had a minor effect on protein solubility and dispersion stability at pH 8. Water and protein holding capacities of the gels were the highest for the phytase-treated sample (91 and 97%, respectively), followed by the sample with added calcium (86 and 94%, respectively) and control sample (60 and 86%, respectively). Gel firmness followed the same pattern. Scanning electron microscopy images revealed an interconnected structured network in the phytase-treated gel, while in the control gel, a more rigid and open structure was observed. The improved gelation properties resulting from the phytase treatment suggest that the protein and soluble dietary fibre-enriched rapeseed press cake ingredient serve as a promising raw material for gelled food systems. The positive effect of calcium addition on gel properties proposes that part of the improvement observed after phytase treatment may be caused by cations released from phytate.

Hybrid products, in which a portion of meat is replaced with plant proteins, could be an effective solution to reduce meat consumption and its environmental impact, and provide well-balanced nutritious food. This study focused on exploring the potential of creating hybrid meat products by high-moisture extrusion from a mixture of minced beef (with 7 or 17% fat) and two different commercial pea protein ingredients. Hybrid extrudates were successfully produced from a 1:1 mixture of beef and either pea protein isolate (PI) or milled texturised pea protein concentrate (TPC). Differences in the appearance, texture and sensory properties of the hybrid extrudates depended both on ingredient properties and extrusion processing parameters (especially temperature). Extrudates with beef and PI were softer and layered, while extrudates with beef and TPC were harder and had smaller fibres. The fat content of the beef did not significantly affect the textural properties of the extrudates. The extrudates with beef and TPC had a meat-like odour and umami taste, while extrudates with beef and PI had a dominant pea-like taste and odour.

The food sector is driven by a large number of actors, including primary producers, manufacturers, logistics providers, retailers, and consumers. At each phase of the food value chain, a significant amount of data is generated that provides important information to the agents involved in processing and flow of food products from farm to fork. Proper handling of food data has a crucial role in providing safe, quality and affordable products to the increasing world population. The independent production of food data, without following any specific guidelines and procedures, often results in inconsistent and incomparable datasets that cannot be directly utilised by multiple users. Data harmonisation means reconciling various types, levels and sources of data in formats that are compatible and comparable, and thus useful for better decision making. In the food sector, one way of performing data harmonisation is to represent food data according to reliable classification and description systems. Another approach towards harmonisation is to match various food concepts to the existing and widely used ontologies. Furthermore, harmonisation is facilitated by following specific guidelines and procedures during data collection processes. This study explores some of the most important tools, frameworks and methodologies for data harmonisation in the food sector.

Cereal grains are the main dietary source of energy, carbohydrates, and plant proteins world-wide. Currently, only 41% of grains are used for human consumption, and up to 35% are used for animal feed. Cereals have been overlooked as a source of environmentally sustainable and healthy plant proteins and could play a major role in transitioning towards a more sustainable food system for healthy diets. Cereal plant proteins are of good nutritional quality, but lysine is often the limiting amino acid. When consumed as whole grains, cereals provide health-protecting components such as dietary fiber and phytochemicals. Shifting grain use from feed to traditional foods and conceptually new foods and ingredients could improve protein security and alleviate climate change. Rapid development of new grain-based food ingredients and use of grains in new food contexts, such as dairy replacements and meat analogues, could accelerate the transition. This review discusses recent developments and outlines future perspectives for cereal grain use.

Extrudates made of 30 different wholegrain oat flour samples with diverse chemical composition were prepared using a twin-screw extruder (screw speed 400 rotations per minute, temperature profile 140-130-90-85 °C (die to feed), flour feed rate was 60 g/min and total moisture content 15%). Each wholegrain oat flour was mixed with 30% rice flour (dry basis) and extruded under constant temperature, screw speed, water and feed rates. Generic descriptive sensory analysis was performed for 10 selected samples. Principal component analysis (PCA) and partial least squares regression (PLS) models were used to assess interactions between the sensory and instrumental data. Degree of extrudate expansion varied between 143 and 305%, while density varied between 198 and 785 kg/m3. Hardness of samples were between 44 and 150 N. As expected, starch content was positively, and fat content negatively correlated with degree of expansion. Musty aroma and the perceived hardness correlated with fat content in the PLS model, while the perceived crispiness correlated with expansion. Quality indicators such as thousand seed weight (TSW), and peak viscosity showed significant correlation with expansion in both instrumental and sensory tests; therefore, they can be utilized as quick predictive measurements to assess the quality of wholegrain oat based extrudates.

This study aimed to understand the powder properties of ingredients (whey and potato protein isolates, fine and coarse non-digestible maltodextrin, instant waxy maize and potato starches) that allow point of consumption machine-production of protein and fibre fortified products of varying consistency. Common characteristics of ingredients suitable for instant food preparation and use included free powder flow (avalanche angles of 42.2–46.4°), large particle size with narrow size distribution (d50 = 177–309 μm), high porosity and rapid de-agglomeration into primary particles in contact with water. Instant production of liquid (

The need for finding sustainable alternatives to animal originated proteins accelerates the development of plant-based innovations. Oat proteins are potential candidates as performance ingredient for tailoring taste and texture. Therefore, the ability of an oat protein isolate (OPI) and two oat protein hydrolysates to form heat-induced gels was analyzed at two pH conditions (4.5 and 8) as well as at two different temperatures (90 and 120 °C). The gelling properties were influenced by enzymatic hydrolysis with trypsin (OPT) and Alcalase® (OPA) to a degree of hydrolysis (DH) of 2%. Enzymatic modification altered the molecular weight distribution as well as the aggregation behavior of the oat protein which in turn affected the structural properties as well as the lightness of the gels. In detail, large aggregates led to an increased gel lightness. Alkaline conditions favored the browning of the gels. However, an increased protein aggregation in OPA-based gels improved the lightness under these conditions. This increased general understanding of the relationship between the overall functional properties of oat protein and its enzymatic modification will support the definition of targeted process windows for specific food applications. Therefore, enzymatic modification is a valuable tool to design plant protein ingredients with tailored functional properties.

The aim of this study was to investigate the performance of rapeseed protein isolate (RPI) or concentrate (RPC) as such and after lactic acid bacteria fermentation as ingredients in composite wheat baking. Bread recipes were developed replacing wheat flour with RPI (10%) or RPC (20%) to obtain a high protein bread. Fermentation of the rapeseed protein ingredients with Weissella confusa A16 enabling synthesis in situ of dextran contributed to obtaining bread with improved textural properties. The in situ produced dextran in RPI (6.1% dry matter) and RPC (5.7% dm) increased the bread specific volume (10% and 14%, respectively) and decreased crumb hardness (35% and 25%, respectively) compared to the respective control breads. Furthermore, fermentation of RPC significantly improved the free amino acid profiles e.g., lysine, methionine, and isoleucine, which are deficient in wheat bread. Protein digestibility in vitro was significantly enhanced in the breads containing fermented RPI, but not in the one with fermented RPC, probably due to the higher level of condensed tannins in RPC after fermentation.

Protein-enriched gluten-free pasta was prepared from oat starch-rich endosperm (SRE), which was substituted with different proportions of oat protein concentrate (OPC) and/or faba protein concentrate (FPC) fractions in order to obtain a similar protein content (18% and 35%). Accordingly, the health claims ‘source of protein’ and ‘high protein’ were achieved. Pasta with OPC and FPC had lower optimal cooking time (8 and 6.3 min), cooking loss (6% and 10.2% dm) and water absorption (152% and 147%) than control SRE pasta (9.3 min; 12.3% dm and 185%). Addition of protein concentrates produced an increase in hardness and chewiness of spaghetti. The glycaemic index of pasta was lowered by the addition of protein ingredients, the lowest value being achieved with FPC. In vitro protein digestibility of pasta increased up to 3.5% for OPC and up to 7.1% in case of FPC addition. The most protein-digestible pasta was that with FPC addition to reach 35% protein content.

This study investigated the effect of pH on fibrous structure formation (protein alignment) during high-moisture extrusion processing of gluten, rice protein, as well as pea protein concentrate, and isolate. The pH of the raw material was shifted to 5 and 7 in water suspension with an acid or base and freeze-dried, after which, conductivity, solubility, water-holding capacity, particle size, and pH were measured. The pH-shifted raw materials were extruded at various temperatures (95–160 °C) and the extrudates were analysed for protein alignment (macro and microstructure), tensile strength, free thiol groups, and cooking properties. In general, all raw materials generated fibrous structure at lower temperatures (115–140 °C) at pH 7 than at pH 5 (135–160 °C). Higher pH and temperature values led to an increased tensile strength and pronounced protein alignment. No such unambiguous link could be observed between the raw material properties and enhanced structure formation. This study showed that the structure formation of the extrudate can be positively influenced by increasing the pH of the raw material, which facilitates the plant protein structuring into appealing meat analogue products.

Editores: Jiménez-López, José Carlos (CSIC); Clemente, Alfonso (CSIC)

The potential to reduce GHG emissions and land use of the diet by replacing animal-based protein sources with foods containing oat protein concentrate (OPC) was analysed by life cycle assessment (LCA) of six different scenarios of daily food intake of one adult. The OPC was used in the preparation of bread and pasta and as a substitute for milk in yoghurt resulting in a higher protein content of these foods. The present study showed, that dietary-related GHG emissions and land use can be reduced by substituting animal-based proteins by foods containing oat protein. If the oat protein (OPC) enriched food items substitute animal based protein sources in the diet proportionally, GHG emission from the diet could be reduced by 8% and land use by 14%. However, if the OPC enriched food items are used specifically to replace intake of all beef and some pork, GHG emissions from the diet could be reduced by 13% and land use by 26%. Thereby, use of new plant-based protein ingredients in diets has a considerable potential to mitigate climate change and reduce land use. Even though the presented scenarios are extreme, they clearly demonstrate the potential that OPC food products made it possible to replace some of the animal-based protein with this plant-based protein source.

Multisensory augmented reality systems have demonstrated the potential of olfactory cues in the augmentation of flavor perception. Earlier studies have mainly used commercially available sample products. In this study, custom rye-based cakes with reduced sugar content were used to study the influence of different odorants on the perceived sweetness. A custom olfactory display was developed for presenting the odorants. The results showed that augmentation of a reduced sugar rye-based cake with localized maltol, vanilla, and strawberry odor increased the perceived sweetness of the cake-odor pair compared to a cake with deodorized airflow. publishedVersion

This study addressed the potential of 3D printing as a processing technology for delivering personalized healthy eating solutions to consumers. Extrusion-based 3D printing was studied as a tool to produce protein- and dietary fibre-rich snack products from whole milk powder and wholegrain rye flour. Aqueous pastes were prepared from the raw materials at various ratios, grid-like samples printed from the pastes at ambient temperature and the printed samples post-processed by oven baking at 150 &deg, C. Printing pastes were characterized by rheological measurements and the baked samples by X-ray micro tomography, texture measurements and sensory analysis. All formulations showed good printability and shape stability after printing. During baking, the milk powder-based samples expanded to a level that caused a total collapse of the printed multiple-layer samples. Shape retention during baking was greatly improved by adding rye flour to the milk formulation. Sensory evaluation revealed that the volume, glossiness, sweetness and saltiness of the baked samples increased with an increasing level of milk powder in the printing paste. A mixture of milk powder and rye flour shows great potential as a formulation for healthy snack products produced by extrusion-based 3D printing.

Ultrasonication alone or in combination with a pH-shifting method could be applied as means for improving the techno-functional properties and performance of barley protein ingredients in liquid food matrix. Ultrasound technology was utilised with and without pH-shifting to 3, 7 and 9 aiming at investigating their impact on primary protein structure, protein solubility, particle size and colloidal stability of an air-classified protein-enriched barley fraction and a barley protein isolate. Shifting the pH of sample dispersion to 9 followed by neutralisation to pH 7 improved protein solubility and colloidal stability of the isolate whereas it had less impact on the protein-enriched fraction. Ultrasound treatment improved both protein solubility and colloidal stability of the protein-enriched fraction at alkaline pH and particle size reduction by ultrasonication was observed at all the studied pH-values. For protein isolate, ultrasonication improved protein solubility at all pH-values and colloidal stability was improved at acidic and neutral pH whereas the sample was inherently stable at alkaline pH. The protein profiles of both ingredients remained unaffected by ultrasound treatment. The results suggest adopting ultrasonication as a promising tool for improving applicability of barley protein ingredients in liquid food systems.

Immersive technologies such as virtual reality and augmented reality have been recently explored in the field of food consumption studies from different perspectives. The present study utilized virtual reality technology in a within-subject experiment with three conditions to examine whether a varying virtual eating environment can alter consumers’ emotional responses (positive, negative, neutral) to the eating situation and whether the resulting emotional responses correlate with consumers’ wanting, liking, and hedonic evaluations of healthy and unhealthy snacks. In addition, the study analyzed whether a virtual eating environment that generates a positive emotional response can raise consumers’ rating of a healthy snack to the same level as an unhealthy snack consumed in a plain, unimmersed environment. The results showed a correlation between positive emotional responses and the pre-tasting evaluations of both snacks. In terms of hedonic evaluations, positive emotional responses correlated mainly with consumers’ evaluation of the unhealthy snack. When pre-tasting wanting and liking evaluations are compared between experimental conditions, the results indicate that a healthy snack is rated higher in a virtual reality environment that induces a more positive emotional response. The healthy snack was also rated at the same level as the unhealthy snack consumed in a plain environment. No differences between conditions were observed in consumers’ hedonic evaluations of the products. EEG and heart rate measurement results indicate that this might be because tasting a healthy snack generates more cognitive processing than an unhealthy snack. This might reduce the influence of the virtual eating environment on consumers’ evaluations. To conclude, virtual reality technologies might have the potential to support consumers’ eating experiences and healthy food choices by improving their evaluations of the products.

High insoluble dietary fibre content causes challenges with structure and texture in extrusion. This paper focused on studying the structure of extrudate enriched with rye bran modified in different ways. Fermentation of rye bran with dextran-producing Weissella confusa (with 10 g/100 g, 5 g/100 g and 0 g/100 g added sucrose as substrate for dextran production), in situ enzymatic production of dextran in the bran and chemical acidification of bran with lactic acid were compared in extrusion trials. Endosperm rye flour was the base in extrusion, of which 32 g/100 g was substituted for rye bran. Fermentation with dextran production showed similar improvement in extrudate expansion as chemically acidified bran samples (489 and 493%), in comparison with native bran (420%). Similarly, these treatments decreased extrudate hardness and increased crispiness index (CI) (16 N, 0.06 and 14 N, 0.071 respectively) compared to the control (39 N, 0.008). Enzymatically produced dextran did not affect expansion, although it decreased hardness (26 N) and increased CI compared to the control (0.023). Chemical changes in the fermented and acidified rye bran included reduction in insoluble dietary fibre (DF) (19 g/100 g → 17 g/100 g) and increase in soluble DF (5.17 g/100 g → 5.51-7.19 g/100 g), as well as soluble protein (8 g/100 g → 11 g/100 g) content. Lactic acid bacteria fermentation or acidification is therefore a promising method to increase the functionality of rye bran in extrusion.

There is a need to find sustainable alternative protein sources in order to meet the increasing protein demand of the growing population. Legumes such as faba beans are underutilized protein rich sources and can be valorized as hybrid protein ingredient through dry fractionation technologies. Also, cereal side streams can be interesting sources towards multifunctional protein ingredients. The aim of this study was to assess the environmental impacts of the production of oat protein concentrate (OPC) and faba bean protein concentrate (FBC) using life cycle assessment (LCA) methodology and to compare the impact per kg protein to other relevant proteins. The OPC is obtained as a side stream of the beta glucan extraction process, which also produces valuable oat oil, while FBC is the only main product obtained from dehulled faba beans. Average European oat cultivation and faba bean cultivation with low and high yield were modelled. Data for protein concentrates production was from real factories who have suitable facilities, but are not currently producing concentrates commercially. The major hotspot in the carbon footprint of oat protein concentrate comes from energy consumption in processing. For faba bean protein concentrate, energy consumption in processing is lower and cultivation of faba bean is the main hotspot. The carbon footprint of oat protein concentrate is more than 50 percent lower, compared to dairy proteins per kg protein, while the carbon footprint of faba bean concentrate protein is 80–90 percent lower. Compared to legume protein sources, OPC has four times higher impacts. This is mainly due to the lower amount of processing steps needed to reach high protein content concentrates from faba beans resulting mainly from relatively lower level of lipids, which enables more energy-efficient dry separation, and high initial protein content of legumes compared to cereals. Moreover, legume cultivation requires very little nitrogen fertilizers due to symbiotic N2 fixation. This study shows that OPC and FBC have lower carbon footprints than animal protein sources. However, it should be remembered, that the environmental impacts of OPC are very sensitive to the allocation method and allocation basis. In this study economic allocation was used and prices of the different products (OPC, oat oil and beta glucan) play a key role in defining the climate impacts of OPC.

Air classification of an industrial barley endosperm fraction with initial protein content of 8.3% mixed with Aerosil 200F flow aid resulted in protein enrichment up to 28.3% with 21.7% protein separation efficiency. By reducing the classifier wheel speed from 21500 rpm to 8000 rpm, the protein separation efficiency increased to 59.4%, whereas the protein content only decreased to 22.3%. Microstructural analysis showed that small starch granules separated together with protein in the fine fraction and had more continuous protein matrix around them. The protein-enriched fraction obtained at 8000 rpm classifier wheel speed had limited protein solubility of 9.3% at native pH 5.1. Solubility increased in acidic (pH 3, 19.6%) and especially in alkaline (pH 11, 91.9%) conditions. Protein fraction had water and oil binding capacities of 1.2 and 1.1 g/g, respectively. Foaming properties tested at different pH-values revealed best capacity at pH 3. Thermograms showed two melting temperatures, varying from 60.0 to 64.2 °C and from 90.5 to 95.5 °C for all the studied fractions. Cereal side-streams such as the industrial barley endosperm fraction can be utilised as potential plant protein ingredient for various food/feed applications. However, further studies are needed to evaluate the technological, nutritional, and sensory characteristics of this protein enriched fraction.

Water suspensions of cellulose nanofibres with xylan, xyloglucan and pectin were studied for foaming and structural properties as a new means for food structuring. The dispersions were analysed with rheological measurements, microscopy and optical coherence tomography. A combination of xylan with TEMPO-oxidized nanocellulose produced a mixture with well-dispersed air bubbles, while the addition of pectin improved the elastic modulus, hardness and toughness of the structures. A similar structure was observed with native nanocellulose, but the elastic modulus was not as high. Shear flow caused cellulose nanofibres to form plate-like flocs in the suspension that accumulated near bubble interfaces. This tendency could be affected by adding laccase to the dispersion, but the effect was opposite for native and TEMPO-oxidized nanocellulose. Nanocellulose type also influenced the interactions between nanofibers and other polysaccharides. For example, xyloglucan interacted strongly with TEMPO-oxidized nanocellulose (high storage modulus) but not with native nanocellulose.

Food structure and cephalic phase factors are hypothesized to contribute to postprandial satiety in addition to established food properties such as energy content, energy density, and macronutrient and fibre composition of a preload. This study aimed to evaluate if the structure of rye products has an impact on subjective feelings of satiety, and whether cephalic phase factors including oral processing, satiety expectations and perceived pleasantness modulate the interaction. Four wholegrain rye based samples (extruded flakes and puffs, bread and smoothie) were studied in terms of texture characteristics, in vivo oral processing, and expected satiety (n = 26) and satiety as well as perceived pleasantness (n = 16) (ClinicalTrials.gov number: NCT02554162). The vast textural differences between products were reflected in mastication process, perceived pleasantness and satiety expectations. Extruded products required the most intensive mastication. Rye puffs and rye bread which were characterised by a solid and porous structure, and showed better satiety effect in the early postprandial phase compared to other products. Mastication effort interacted with satiety response. However, the products requiring the most intense mastication effort were not the most satiating ones. It seems that there are some food structure related factors that influence both mastication process and postprandial satiety, the mastication process itself not being the mediating factor. Higher palatability seems to weaken postprandial satiety response.

This study was jointly funded by the Academy of Finland (Academy Professorship, Kaisa Poutanen - grant number 131460) and by the Raisio Plc's Research Foundation (personal grant to Syed Ariful Alam, grant decisions of 2016). Structural and textural properties as well as the dietary fibre content of solid cereal foams influence the oral breakdown of structure, bolus formation and digestibility. The aimof this studywas to investigate howstructural differences of solid cereal foams (puffs vs. flakes) affect in vivo chewing and in vitro starch digestion. Four extruded puffs and flakes were produced from endosperm rye flour by extrusion processing without or with 10% rye bran (RB) addition. Extruded puffs and flakes were masticated by fifteen healthy females and the process was monitored using electromyography. Extruded puffs were more porous than flakes (97% vs 35%). The two productswere also significantly different (p b 0.05) in their structural and textural properties such as expansion, hardness, density and crispiness. A negative correlation was observed between hardness and crispiness index (p b 0.05, r=−0.950) and density and porosity (p b 0.05, r=−0.964). Addition of 10% RB had a significant effect on structural, textural and mastication properties both for puffs and flakes. Mastication of puffs required less total work than flakes (204 vs. 456%) and theywere degraded to smaller particles than flakes during mastication. Irrespectively of the considerable differences in structure, texture and oral disintegration process, no significant (p b 0.05) differenceswere observed between puffs and flakes (86.4 vs. 85.1) in terms of starch hydrolysis index. RB addition increased the hydrolysis index of puffs and flakes to 89.7 and 94.5, respectively, which was probably attributable to the increased number of particles in the bolus.

The global production of pulses, such as various peas, beans, lupines, and lentils, is about 77 million metric tons. Pulses are diverse in their traditional food uses in Asia, Africa, and America, where they have been used, for example, in soups, spreads, meal components, snacks, and breakfast items. Having high protein content (about 20–40%), pulses have recently gained interest when alternative sustainable protein sources are considered. Pulses have been used for protein enrichment in pasta and bread, and they also are suitable ingredients in gluten-free foods. Wet and dry fractionation methods as well as bioprocessing such as germination and fermentation provide useful tools for development of new functional pulse ingredients. The use of pulses is bound to increase in the future, and especially in combination with cereal raw materials they may find new applications meeting both sensory and nutritional needs of consumers on all continents.

The snack product category is lacking palatable, high dietary fiber containing products. This study explored how the addition of native or fermented rye bran influences the texture and sensory properties of endosperm rye flour based extrudates. In addition, mastication and bolus properties (n = 26), and in vitro starch digestibility were assessed. Three high fiber extrudates based on endosperm rye flour (EF) were produced with addition of either 40% native rye bran (NBE) or 40% fermented rye bran (FBE), and with no added bran (EFE) to achieve two pairs of extrudates to compare. EFE and FBE had different composition but resembled each other regarding macrostructure and the second pair (NBE vs. FBE) had similar core composition but different structure due to bran fermentation. The fermentation of bran was performed using exopolysaccharide (EPS)-producing strain Weissella confusa, which led to 3% (3 g per 100 g bran; dry weight) in situ dextran production. The compositionally similar extrudates (NBE vs. FBE) varied in both structure and instrumental texture: FBE were less dense, less hard and crispier than NBE. The extrudates with different composition (EFE vs. FBE) varied regarding instrumental texture: FBE were less hard and crispier than EFE. There were also subtle structural differences FBE being somewhat denser than EFE. NBE and FBE differed regarding sensory texture while textures of EFE and FBE were perceived similar. Mastication properties of the different products did not exhibit remarkable differences. There was a large number of smaller particles in both NBE and FBE bolus samples. The fragile structure of FBE, and its lower bolus viscosity, led to high in vitro starch digestibility. The results demonstrate that the structural attributes of the extrudates, rather than the core composition, dictate the breakdown pattern during mastication and in vitro starch digestibility. The extrudates with similar composition may be digested at different rates depending on their structural attributes. Although FBE had higher in vitro starch digestibility, its high DF content, palatable texture and improved sensory properties were important determinants underlying eating quality and therefore it could be a promising product to snack food category.

Background During the industrial production of β-glucan, a protein-rich fraction remains as a by-product. Recovery of this protein as oat protein concentrate (OPC) results in a source of cereal protein for food and improves the overall economy of the process. In this study, a yoghurt-type product is developed by lactic acid fermentation of an OPC suspension after subjection to heat treatment to assure starch gelatinization. Results In detail, the process of yoghurt production involved an initial heating step to 90 °C, followed by 24 h fermentation with a starter culture consisting of Lactobacillus delbrueckii subsp. bulgaricus und Streptococcus thermophilus. The resulting yoghurt-type product was mildly sour (pH 4.2) with a certain amount of lactic acid (3.3 ± 0.2 g kg-1 ) and contained 4.9 × 106 cfu g-1 lactobacillus after 24 h fermentation. Scanning electron microscopy revealed a porous network presumably built up from the gelatinized starch fraction containing aggregated structures, between which were assumed to be aggregated oat proteins. Moreover, to a limited extent, proteolysis occurred during fermentation. Thus some of the proteolytic enzymes present in the yoghurt culture cleaved oat protein and released peptides. However, the effect on essential amino acids was small. Conclusion The results of this study provide a deeper knowledge into the role of starch and protein in fermented OPC yoghurts. The structure of fermented OPC verifies the applicability of oat protein as an alternative source for yoghurt-type products. © 2019 Society of Chemical Industry.

Foaming ability of oat protein isolate (OPI) was analysed at pH 4 and 7. Foaming properties were influenced by partial hydrolysis with trypsin (OPT) and alcalase (OPA). The viscoelasticity of the protein film, the interactions between the protein molecules, and the network forming within the protein film were analysed by interfacial rheology. At pH 7, foams made of OPI and OPT were found to be stable with OPI showing the fastest foaming ability. At pH 4, the foaming properties of OPI were found to be poor due to limited solubility. The specific cleavage pattern of trypsin resulted in peptides with improved foaming properties, especially at pH 4, resulting in a homogenous foam structure, a fast foaming ability, and a highly viscoelastic interfacial film. The formation of a thick steric protein layer at pH 7 and the formation of strong hydrophobic interactions at pH 4 were found to be the dominating foam stabilisation mechanisms. In conclusion, oat protein may serve as a food ingredient with targeted functional properties.

Article title: Factors affecting structural properties and in vitro starch digestibility of extruded starchy foams containing bran Article reference: YJCRS2207 Journal title: Journal of Cereal Science First author: Syed Ariful Alam Final version published online: 7-SEP-2016 Full bibliographic details: Journal of Cereal Science (2016), pp. 190-197 DOI information: 10.1016/j.jcs.2016.08.018 Rye bran of two different particle sizes (coarse: 440 mm and fine: 28 mm) were prepared by milling of commercial rye bran. Coarse and fine rye bran was added into a blend of rye endosperm flour and corn starch (70:30) to achieve two bran levels, 15 or 30%, to produce directly puffed extrudates. A co-rotating twin screw extruder was used with a screw speed of 500 rpm, barrel temperature profile: 40-70-75-90- 95-110-110 C and constant feed rate of 67 g/min. Feed moisture content of 17% was used either as in barrel-water feed or as preconditioning. Fine bran addition effectively improved macrostructural properties as compared to coarse bran through increasing expansion by 3.3e11.7% and piece density by 3.8 e10.5%. Reduction of bran particle size significantly (P < 0.05) increased crispiness by 66.7e203.3%. Particle size reduction of bran had only minor influences on cell wall thickness, cell area and hydrolysis index of the extrudates. Extrudates made with 30% fine bran at in barrel-water feed provided the crispiest extrudates with lower in vitro hydrolysis index. The results demonstrated that the macrostructural and mechanical properties of extrudates containing rye bran can be improved by reducing bran particle size.

Growing global populations and limited resources require more sustainable use of food crops. Lifestyle-related health problems, such as obesity and type 2 diabetes, are also an increasing problem in many parts of the world. Major agricultural side-streams, such as cereal bran, oil-press residues and pomace, are currently used predominantly for feed and fuel. However, they have the potential to be sustainable sources of healthy proteins, fibers, and bioactive compounds for human consumption if challenges related to flavor and texture are overcome. Novel processing methods are needed to create healthy and palatable ingredients from agricultural side-streams. From economic and sustainability perspectives, these methods must be energy and water efficient. Dry-milling and dry-fractionation are energy-lean methods that can be used to produce value-added hybrid ingredients from side-streams. These ingredients may be processed further using bioprocessing, thermome-chanical processing, or other methods to improve their applicability in food products.

Mild drying and extrusion processing of side streams from berry juice production can enable retention of valuable compounds in the food chain and reduce waste production. The aim of this study was to evaluate the applicability of using hot air (HA) and microwave assisted hot air (MWHA) drying combined with extrusion for conversion of bilberry press cake into value-added extruded food products. Bilberry (Vaccinium myrtillus L.) press cake was dried at 40 °C by HA and MWHA drying to a moisture content of 17% (w/w). A twin screw extruder (average feed rate 72 g/min, temperature profile 135-128-89-69 °C) was used to extrude products containing organic wholegrain rye flour and 10 % or 25 % dried bilberry press cake powder. A consumer panel (n = 15) evalutaed four extrudates on hedonic and Just-about-rigth (JAR) scales, with a mian focus on textrue properties. The results indicate that different drying tecniques implied a difference in processing time (40 % reduction with MWHA drying). However, the retention of total phenolics, physical characteristics and sensory attributes of extruded snacks containing bilberry powders were independent of drying techniques. In sum, powder of bilberry press cake can be incorporated in cereal extruded snacks with enhanced phenolic content and potential for palatable sensory properties.

In this study, the applicability of extrusion-based 3D printing technology for food pastes made of protein, starch and fiber-rich materials was assessed, as a starting point in the development of healthy, customized snack products. The printability of starch-, cellulose nanofiber-, milk powder-, oat- and faba bean protein-based materials and their mixtures was evaluated by examining the ease and uniformity of extrusion as well as the precision and stability of the printed pattern. The best printing precision and shape stability was obtained with a semi-skimmed milk powder-based paste. Rheological measurements revealed that the shape stability after printing was linked with the yield stress of the paste. Post-processing by oven drying was most successful at high initial solids contents (

Postprandial high glucose and insulin responses after starchy food consumption, associated with an increased risk of developing several metabolic diseases, could possibly be improved by altering food structure. We investigated the influence of a compact food structure; different wheat products with a similar composition were created using different processing conditions. The postprandial glucose kinetics and metabolic response to bread with a compact structure (flat bread, FB) was compared to bread with a porous structure (control bread, CB) in a randomized, crossover study with ten healthy male volunteers. Pasta (PA), with a very compact structure, was used as the control. The rate of appearance of exogenous glucose (RaE), endogenous glucose production, and glucose clearance rate (GCR) was calculated using stable isotopes. Furthermore, postprandial plasma concentrations of glucose, insulin, several intestinal hormones and bile acids were analyzed. The structure of FB was considerably more compact compared to CB, as confirmed by microscopy, XRT analysis (porosity) and density measurements. Consumption of FB resulted in lower peak glucose, insulin and glucose-dependent insulinotropic polypeptide (ns) responses and a slower initial RaE compared to CB. These variables were similar to the PA response, except for RaE which remained slower over a longer period after PA consumption. Interestingly, the GCR after FB was higher than expected based on the insulin response, indicating increased insulin sensitivity or insulin-independent glucose disposal. These results demonstrate that the structure of wheat bread can influence the postprandial metabolic response, with a more compact structure being more beneficial for health. Bread-making technology should be further explored to create healthier products.

The effects of air classification and lactic acid bacteria fermentation on the reduction of anti-nutritional factors (vicine and convicine, trypsin inhibitor activity, condensed tannins and phytic acid) and in vitro protein and starch digestibility of faba bean flour were studied. Free amino acid (FAA) profile analysis was also carried out. Air classification allowed the separation of the flour into protein and starch rich fractions, showing different chemical compositions and microstructures. Lactobacillus plantarum growth and acidification in faba bean flour and its fractions were assessed. The anti-nutritional compounds were separated mostly to the fine protein-rich fraction. Fermentation caused the decrease of vicine and convicine contents by more than 91% and significantly reduced trypsin inhibitor activity and condensed tannins (by more than 40% in the protein-rich fraction). No significant (P>0.05) variation was observed for total phenols and phytic acid content. Fermentation increased the amount of FAA, especially of the essential amino acids and γ-aminobutyric acid, enhanced the in vitro protein digestibility and significantly lowered the hydrolysis index. This work showed that the combination of air classification and fermentation improved nutritional functionality of faba bean flour which could be utilized in various food applications.

Chemical composition, baking process and structure of breads influence their degradation in digestion leading to different postprandial responses. Rye bread has a very different structure as compared to wheat bread, and rye breads are known to induce lower postprandial insulin responses than wheat bread. The aim of this study was to find out potential differences in mastication and initial starch hydrolysis rate of rye and wheat breads. Three rye breads (wholemeal rye, endosperm rye and endosperm rye with gluten) and wheat bread were masticated by fifteen participants and the process was monitored using electromyography. The particle size distribution and initial in vitro starch hydrolysis of the bread boluses were analysed. Specific volume correlated negatively and closed porosity of breads correlated positively with work required for mastication. When compared to wheat bread, wholemeal rye bread required more work for mastication process (p = 0.004). Rye breads were degraded to smaller particles than wheat bread during mastication. There was a trend (p = 0.098) towards slower in vitro starch hydrolysis rate in rye bread boluses than in wheat bread boluses. The results indicate that the digestion process of rye breads differs from that of wheat bread already in the early phase of digestion. This may be one reason behind the unique postprandial responses reported for rye breads.

In this study, the effect of steam explosion (SE) treatment on microstructure, enzymatic hydrolysis and baking quality of wheat bran was investigated. Coarse and fine bran were treated at different steam temperatures (120-160 degrees C) and residence times (5 or 10 min) and then hydrolysed with carbohydrase enzymes. The SE treatment increased water extractable arabinoxylan (WEAX) content from 0.75 to 2.06% and reducing sugars from 0.92 to 2.41% for fine bran. The effect was more pronounced with increased SE temperature and residence time. The highest carbohydrate solubilisation was observed in fine bran at SE treatment of 160 degrees C, 5 min. WEAX content increased to 3.13% when this bran was incubated without enzyme, while WEAX content increased to 9.14% with enzyme addition. Microscopic analysis indicated that cell wall structure of wheat bran was disrupted by severe SE conditions. Supplementation of SE treated (150 degrees C, 10 min) bran at 20% replacement level decreased the baking quality of bread. However SE followed by enzymatic hydrolysis increased specific volume and decreased crumb hardness (on the day of baking and after three days of storage). Phytic acid content of bread supplemented with SE treated bran was lower than the one supplemented with untreated bran. (C) 2017 Elsevier Ltd. All rights reserved.

Oat is a robust high-protein cereal that grows well in northern regions. Unlike Triticeae cereals, the major storage protein is a globulin, which is higher in essential amino acids than prolamin storage proteins. Oat protein can be tolerated by most celiac individuals, making it an interesting raw material for the ever-expanding gluten-free market. Although well-suited in bakery products, the applicability of oat protein is still limited in liquid and semisolid foods because of its low solubility at neutral and mildly acidic conditions. Enzymatic modifications have shown promising results, and could be utilized for the expansion of applications in the future. The recent developments in new sustainable technologies for oat fractionation have enabled production of oat protein ingredients with better functionalities.