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Date fruits (Phoenix dactylifera) of ten varieties, collected in the United Arab Emirates, were studied to determine their dietary fiber content and composition. Fourier transform infrared (FTIR) spectroscopy indicated that the dietary fiber components in all the date fruit varieties was similar. The major dietary fiber components, including cellulose, hemicellulosic components, lignin, and pectin, were analyzed by the Uppsala method. The total dietary fiber content in the date fruits analyzed (5.2%–8.3%) is comparable to commonly consumed dried fruits and is correlated with the content of lignin. The lignin was the main determinant of the total dietary fiber content in dates and its content was higher in semi-hard and hard fruit varieties.

Material disintegration is the primary step in β-glucan determination in cereal grains. This study investigated the effect of disintegration approach on β-glucan content, determined by an enzymatic method in mature kernels of barley and oat. Milling with a coffee grinder was found to be relevant only for pre-disintegration and homogenization of the grain (4.6% and 3.2% β-glucan content was found in barley and oats, respectively). Ball milling appeared to be the most efficient approach for reducing material particle size, but resulted in samples with underestimated β-glucan content (4.6% and 3.3% in barley and oats, respectively). Grinding with mortar and pestle in liquid nitrogen and repeated centrifugal milling were found to be the optimal disintegration methods for barley kernels (5.2% and 4.7–4.8% β-glucan content, respectively). Grinding with mortar and pestle (either in dry state or in liquid nitrogen) and single centrifugal milling were the optimal disintegration methods for oat kernels (3.6–3.9% and 3.3–3.4% β-glucan content, respectively).

Date fruits vary widely in the hardness of their edible parts and they are classified accordingly into soft, semi-dry, and dry varieties. Fruit texture, a significant parameter in determining consumer acceptance, is related to the tissue structure and chemical composition of the fruit, mainly the ratio of sucrose to reducing sugars. This study aimed to understand the relationship between the chemical composition, microstructure, and texture profile of 10 major Emirati date fruits. The soluble sugars, glucose and fructose, represent ca 80 g/100 g of the fruits on the basis of dry weight (DW) while the dietary fiber contents varied 5.2–7.4 g/100 dg D.W. with lignin being the main determinant of the variability. The textures of the samples were studied using instrumental texture profile analysis. While no correlation was found between the soluble sugar and texture parameters in this study, the different fiber constituents correlated variably with the different parameters of date fruit texture. Lignin, arabinoxylan, galactomannan, and pectin were found to correlate significantly with fruit hardness and the related parameters, gumminess and chewiness. Both lignin and arabinoxylan correlated with resilience, and arabinoxylan exhibited a strong correlation with cohesiveness.

In this study, 50% sifted barley flour from six different varieties and 50% refined wheat flour was used to bake bread. The flour mixture and the bread crumb and crust were analysed for content and composition of total dietary fibre, arabinoxylan, fructan, β-glucan, starch and resistant starch. Total dietary fibre content and extractability were not changed significantly by bread making. The extractability of mixed-linkage (1 → 3), (1 → 4)- β-D-glucan (β-glucan) increased with baking, while the average molecular weight of β-glucan decreased. However in one variety, SLU 7, higher average molecular weight was maintained and a different pattern was apparent in the molecular weight distribution. SLU 7 is thereby promising for inclusion in bread where a higher molecular weight of β-glucan is preferred, especially since the content of β-glucan in SLU 7 is high. The resistant starch formed positively correlated with amylose content. The high amylose variety yielded 2.9% resistant starch in the bread crumb, making an important contribution to total dietary fibre.

Wheat bran and rye bran are mostly used as animal feed today, but their high content of dietary fiber and bioactive components are beneficial to human health. Increased use of bran as food raw material could therefore be desirable. However, bran mainly contains unextractable dietary fiber and deteriorates the sensory properties of products. Processing by extrusion could increase the extractability of dietary fiber and increase the sensory qualities of bran products. Wheat bran and rye bran were therefore extruded at different levels of moisture content, screw speed and temperature, in order to find the optimal setting for increased extractability of dietary fiber and positive sensory properties. A water content of 24% for wheat bran and 30% for rye bran, a screw speed of 400 rpm, and a temperature of 130 °C resulted in the highest extractability of total dietary fiber and arabinoxylan. Arabinoxylan extractability increased from 5.8% in wheat bran to 9.0% in extruded wheat bran at those settings, and from 14.6% to 19.2% for rye bran. Total contents of dietary fiber and arabinoxylan were not affected by extrusion. Content of β-glucan was also maintained during extrusion, while its molecular weight decreased slightly and extractability increased slightly. Extrusion at these settings is therefore a suitable process for increasing the use of wheat bran and rye bran as a food raw material.

In this study, β-glucan in samples of sifted flour from six barley varieties was sequentially extracted with water and NaOH obtaining three fractions: water-extractable (WE), NaOH- extractable (NaE) and residual (Res). β-Glucan isolates were incubated with lichenase and oligomers released were analysed with high performance anion exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD). A higher ratio of 3-O-β-cellobiosyl-D-glucose (DP3) to 3-O-β-cellotriosyl-D-glucose (DP4) is reported in WE, NaE and Res fractions in variety SLU 7 (shrunken endosperm) compared to the other varieties, suggesting a more packed β-glucan structure. Water-extractable and water-unextractable β-glucan fractions were incubated with wheat extract and effects of wheat β-glucanase on the structure was assessed after lichenase digestion and analysis with HPAEC-PAD. Findings suggest that wheat β-glucanase manifests a selective hydrolysis towards β-glucan with lower DP3/DP4 ratio and that β-glucan of SLU 7 is composed of a population with higher DP3/DP4 ratio and hence with a more tighten structure which may be more resistant to enzymic action. Overall, the results obtained are of interest to characterise barleys differing in starch and dietary fibre composition, specifically shrunken endosperm barley SLU 7 in the perspective of its inclusion in the production of β-glucan enriched foods.

To describe a more sustainable food sector, a supply chain approach is needed. Changing a supply chain inevitably means that various attributes of the product and its system will change. This project assumed this challenge and delivered detailed descriptions, life cycle assessment (LCA) evaluations, and consequence assessments of the supply chains of six commodities, i.e., milk, cheese, beef, pork, chicken, and bread, from a Swedish region. This paper presents results for the pork supply chain. In the project setup, experts on production along supply chains designed three scenarios for environmentally improved systems. These scenarios, i.e., the ecosystem, plant nutrients, and climate scenarios, were intended to address different clusters of environmental goals. The next step was to challenge these scenarios by considering their possible consequences for products and systems from the food safety, sensory quality, animal welfare, consumer appreciation, and (for primary production only) cost perspectives. This led to changes in production system design to prevent negative consequences. The final supply chains were quantified using LCA and were again assessed from the three perspectives. The scenario design approach worked well, thoroughly and credibly describing the production systems. Assessment of consequences bolstered the credibility and quality of the systems and results. The LCA of pig production and smoked ham identified large potentials for improvement by implementing available knowledge: global warming potential (GWP) could be reduced 21–54 % and marine eutrophication by 14–45 %. The main reason for these improvements was improved productivity (approaching the best producers’ current performance), though dedicated measures were also important, resulting in increased nitrogen efficiency, more varied crop rotations for crop production and better production management, and improved animal health and manure management for animal production. Reduced post-farm wastage contributed as did reduced emissions from fertilizer production. The working approach applied was successful in integrating LCA research with food system production expertise to deliver results relevant to supply chain decision-makers. The consequence assessments brought considerable value to the project, giving its results greater credibility. By introducing constraints in the form of “no negative consequences and no increased costs,” the work was “guided” so that the scenario design avoided being hampered by too many opportunities.