The aim of this study is to up-cycle mushroom production waste by incorporating macerated mushroom caps and stalks into moulded Kraft pulp packaging material and to compare the properties of this new material with existing food packaging materials, namely moulded pulp packaging (MPP) and polypropylene (PP) punnets. Corrugated cardboard fibre (CCF) was blended with 30% waste mushroom caps and stalks (MW) with and without addition of alkyl ketene dimer (AKD). Microbiological assessment of the packaging material from selected production stages and the finished punnets was conducted the determine levels of aerobic colony count, Pseudomonas spp., and yeasts and moulds. Also, finished punnets were characterized for their physical properties (moisture, density, surface hydrophobicity, mechanical properties, microstructure) and used for cold storage trials using fresh mushrooms comparing performance to MPP and PP punnets in terms of change in colour (CIE L*, a*, b*) and microbial load of the packed mushrooms. During seven days of cold storage of fresh mushrooms, both mushrooms and packaging materials were analysed for their total aerobic bacteria, Pseudomonas spp., and yeasts and moulds. Results showed that at the end of the storage, MW/CCF and MW/ CCF + AKD punnets showed similar performance with PP punnet on the microbial quality of fresh mushroom. The fresh mushrooms had better colour compared with those stored in MPP. The paper-based punnets had higher microbial growth in the packaging material than PP punnet. Incorporation MW improved the mechanical properties of CCF. The MW/CCF and MW/CCF + AKD punnets had a higher Young's modulus than MPP. Results indicated that, moulded pulp punnets prepared using 30% mushroom waste used for fresh mushroom packaging provide the similar microbial quality with better product colour compared with commercial counterparts while allowing agri-waste up-cycling.

Cholinesterases, involved in acetylcholine catabolism in the central and peripheral nervous system, have been strongly linked with neurodegenerative diseases. Current therapeutic approaches using synthetic drugs present several side effects. Hence, there is an increasing research interest in naturally-occurring dietary polyphenols, which are also considered efficacious. Food processing by-products such as brewer’s spent grain (BSG) would be a potential bio-source of polyphenols. In this study, polyphenol-rich BSG extracts using 60% acetone and 0.75% NaOH solutions were generated, which were further subjected to liquid–liquid partitioning using various organic solvents. The water-partitioned fractions of the saponified extracts had the highest total polyphenol content (6.2 ± 2.8mgGAE/g dw) as determined by Folin–Ciocalteu reagent, while the LC-MS/MS showed ethyl acetate fraction with the highest phenolics (2.9 ± 0.3mg/g BSG dw). The best inhibitions of acetyl- (37.9 ± 2.9%) and butyryl- (53.6 ± 7.7%) cholinesterases were shown by the diethyl ether fraction of the saponified extract. This fraction contained the highest sum of quantified phenolics (99 ± 21.2µg/mg of extract), and with significant (p < 0.01) inhibitory contribution of decarboxylated-diferulic acid. Amongst the standards, caffeic acid presented the highest inhibition for both cholinesterases, 25.5 ± 0.2% for acetyl- and 52.3 ± 0.8% for butyryl-cholinesterase, respectively, whilst the blends insignificantly inhibited both cholinesterases. The results showed that polyphenol-rich BSG fractions have potentials as natural anti-cholinesterase agents.

For every 1 tonne of bananas produced, 3 tonnes of pseudostem waste is also created. The aim of this research is to improve the pre-treatment methods used in converting this renewable resource to bioethanol. The microwave-assisted liquid hot water and alkaline with sodium hydroxide were performed on banana pseudostem followed by saccharification and fermentation to ethanol. The liquid hot water pre-treatment was performed over a range of severities (1.88–4.84). The alkaline pre-treatment was carried out to evaluate the effect of NaOH loading (0.09–0.3 g NaOH g−1 dry banana pseudostem) and severity factor (3.65–4.84). The severity factor of 4.84 from the liquid hot water pre-treatment and run 1 (Log Ro 3.65, 0.09 g NaOH g−1 dry banana pseudostem) from the alkaline pre-treatment reached the highest enzymatic hydrolysis yields for each pre-treatment conditions and were chosen to be submitted to fermentation. Subsequently, simultaneous saccharification and fermentation (SSF) at 25 °C for 120 h, using samples from alkaline (Log Ro 3.65, 0.09 g NaOH g−1 dry banana pseudostem) and liquid hot water (Log Ro 4.84) pre-treatments, resulted in 92 wt% and 95 wt% of the theoretical ethanol yield respectively, comparing to 60 wt% from the untreated biomass. The liquid hot water is considered a more suitable pre-treatment, as it is more economical and is an environmentally friendly alternative compared to the alkaline pre-treatment. The latter can lead to pollution as the sodium discharge in the process effluent is difficult to recycle and so may limit its application on a commercial scale.

Background: The world's demand for animal protein is expected to double by 2050. The environmental and health concerns about its production and consumption have thus promoted the evaluation of alternative sources. Oilseed press cakes and meals represent a promising alternative, due to high levels of production globally, and because they are naturally rich in high quality protein. Scope and approach: This review will provide information on the suitability of obtaining protein from the main oilseeds (soya, rapeseed/canola and sunflower). Topics covered will be chemical, protein and amino acid composition; patented and published protein extraction protocols, and the issue of antinutrients and protein digestibility. Key findings and conclusions: On average, crude protein percentages are soybean (32-43.6% DW) > rapeseed/ canola (25-30% DW) > sunflower (10-27% DW). Soy and rape have well balanced amino acid composition, while sunflower is deficient in lysine. Rape contains high levels of antinutrients, also present in soybean. Aqueous extraction remains the protein-enrichment technique of choice in commercial processes, although the use of salt instead of acid or alkali has been a major improvement regarding the protein quality and environmental hazards. Nevertheless, the use of physical methodologies appears as a "green" and affordable option, adequate as well to preserve proteins quality. Despite its outstanding functional and nutritional properties, soy protein allergenicity remains the main barrier for consumption, and also for rape. Sunflower protein low allergenicity and absence of antinutrients forecasts increased use.

The recovery of antioxidant polyphenols from light, dark and mix brewer's spent grain (BSG) using conventional maceration, microwave and ultrasound assisted extraction was investigated. Total polyphenols were measured in the crude (60% acetone), liquor extracts (saponified with 0.75% NaOH) and in their acidified ethyl acetate (EtOAc) partitioned fractions both by spectrophotometry involving Folin-Ciocalteu reagent and liquid-chromatography-tandem mass spectrometry (LC-MS/MS) methods. Irrespective of the extraction methods used, saponification of BSG yielded higher polyphenols than in the crude extracts. The EtOAc fractionations yielded the highest total phenolic content (TPC) ranging from 3.01 ± 0.19 to 4.71 ± 0.28 mg gallic acid equivalent per g of BSG dry weight. The corresponding total polyphenols quantified by LC-MS/MS ranged from 549.9 ± 41.5 to 2741.1 ± 5.2 µg/g of BSG dry weight. Microwave and ultrasound with the parameters and equipment used did not improve the total polyphenol yield when compared to the conventional maceration method. Furthermore, the spectrophotometric quantification of the liquors overestimated the TPC, while the LC-MS/MS quantification gave a closer representation of the total polyphenols in all the extracts. The total polyphenols were in the following order in the EtOAc fractions: BSG light > BSG Mix > BSG dark, and thus suggested BSG light as a sustainable, low cost source of natural antioxidants that may be tapped for applications in food and phytopharmaceutical industries.

Duckweed has been proposed as a potential raw material to produce renewable biofuels, signified by: its high productivity and low competition with agriculture; its high proportion of carbohydrate (cellulose and starch); a low lignin content, which avoids the likely recalcitrance of cellulose to saccharification. This study has investigated the effect of hydrothermal pre-treatment on structural and chemical changes in Brazilian duckweed (L. punctata) biomass as well as its conversion to bioethanol, focusing on the hydrolysis and fermentation of the cellulose fraction. The biomass was hydrothermally pre-treated over a range of severities (1.9-4.8) and then subjected to simultaneous saccharification and fermentation. The best pre-treatment condition was at a severity factor of 3.9; this condition produced the highest ethanol yield (89 wt% of the theoretical potential yield). This represents a 63 wt% increase compared to untreated biomass. Hydrothermal pre-treatment has been shown to be a suitable technology for increasing ethanol yields from L. punctata biomass towards the theoretical maximum.

In the UK peat has been used as a raw material for containerised plant production over the last 60 years. There has, however, in more recent times, been a push from both the UK Government and consumers to expand the list of materials available for containerised production, because of environmental concerns surrounding peat harvesting. This has presented the industry with a significant challenge, due to the multiple benefits of peat, but also provides security by not being solely reliant on a single raw material. Over the last 10 years growing media manufacturers have played a crucial role in sourcing and conditioning four main types of non-peat materials: coir, wood fibre, bark and green compost. Increasing the use of these materials will move the UK towards responsibly sourced growing media ( RSGM), but a number of significant barriers exist to widespread adoption and use by growers. This paper describes part of an integrated experimental and on-site testing program of work that has been developed to promote the transition to RSGM. The method advocates a move away from iterative stand-alone `look-see' trials towards a novel innovative, predictive `unifying multivariate model' which will identify high performing blends. The blends are being tested for the main users of growing media in the UK, which includes hardy nursey stock, bedding plants, soft fruit, top fruit, vegetables, protected edibles and mushrooms. Where appropriate, propagation and main growth phase stages are evaluated. Shelf-life performance of marketable products are also quantified. The ability to target desirable physical or chemical characteristics and predict blend performance from a range of raw material types and sources will not only be cost effective, but will also accelerate the identification and use of new raw materials for use in horticulture plant production systems.

Approximately 88 Million tonnes (Mt) of food is wasted in the European Union each year and the environmental impacts of these losses throughout the food supply chain are widely recognised. This study illustrates the impacts of food waste in relation to the total food utilised, including the impact from food waste management based on available data at the European level. The impacts are calculated for the Global Warming Potential, the Acidification Potential and the Eutrophication Potential using a bottom-up approach using more than 134 existing LCA studies on nine representative products (apple, tomato, potato, bread, milk, beef, pork, chicken, white fish). Results show that 186 Mt CO2-eq, 1.7 Mt SO2-eq. and 0.7 Mt PO4-eq can be attributed to food waste in Europe. This is 15 to 16% of the total impact of the entire food supply chain. In general, the study confirmed that most of the environmental impacts are derived from the primary production step of the chain. That is why animal-containing food shows most of the food waste related impacts when it is extrapolated to total food waste even if cereals are higher in mass. Nearly three quarters of all food waste-related impacts for Global Warming originate from greenhouse gas emissions during the production step. Emissions by food processing activities contribute 6%, retail and distribution 7%, food consumption, 8% and food disposal, 6% to food waste related impacts. Even though the results are subject to certain data and scenario uncertainties, the study serves as a baseline assessment, based on current food waste data, and can be expanded as more knowledge on the type and amount of food waste becomes available. Nevertheless, the importance of food waste prevention is underlined by the results of this study, as most of the impacts originate from the production step. Through food waste prevention, those impacts can be avoided as less food needs to be produced.

Purpose The term bioaccessibility refers to the proportion of a nutrient released from a complex food matrix during digestion and, therefore, becoming potentially available for absorption in the gastrointestinal tract. In the present study, we assessed the starch and protein bioaccessibility from a range of wheat endosperm products differing in particle size. Methods Five porridge meals (size A, flour, mean particle size 0.11 mm, size B, small, mean particle size 0.38 mm, size C, semolina, mean particle size 1.01 mm, size D, medium, mean particle size 1.44 mm, size E, large, mean particle size 1.95 mm) with theoretically different postprandial glycaemic responses were subjected to oral processing in vitro, followed by simulated gastric and duodenal digestion. Results A significant increase ( P < 0.001) in starch degradation was observed in size A (52%) compared with size E (25%). Both sizes C and D gave less, although not significantly, digestible starch (32 and 28%, respectively). The glucose release significantly decreased as the particle size of the meal increased (92.16% detected for size A vs 47.39% for size E). In agreement with starch degradation and glucose release, size A gave the most digestible protein. Conclusions This data provide further evidence that, by decreasing the size of wheat endosperm, starch release and glycaemic response are enhanced. We also showed that protein bioaccessibility followed a similar trend as for starch digestion. Finally, these results support the hypothesis that different degrees of starch encapsulation elicit different blood glucose responses.

BACKGROUND:Rice straw and husk are globally significant sources of cellulose-rich biomass and there is great interest in converting them to bioethanol. However, rice husk is reportedly much more recalcitrant than rice straw and produces larger quantities of fermentation inhibitors. The aim of this study was to explore the underlying differences between rice straw and rice husk with reference to the composition of the pre-treatment liquors and their impacts on saccharification and fermentation. This has been carried out by developing quantitative NMR screening methods.RESULTS:Air-dried rice husk and rice straw from the same cultivar were used as substrates. Carbohydrate compositions were similar, whereas lignin contents differed significantly (husk: 35.3% w/w of raw material; straw 22.1% w/w of raw material). Substrates were hydrothermally pre-treated with high-pressure microwave processing across a wide range of severities. 25 compounds were identified from the liquors of both pre-treated rice husk and rice straw. However, the quantities of compounds differed between the two substrates. Fermentation inhibitors such as 5-HMF and 2-FA were highest in husk liquors, and formic acid was higher in straw liquors. At a pre-treatment severity of 3.65, twice as much ethanol was produced from rice straw (14.22% dry weight of substrate) compared with the yield from rice husk (7.55% dry weight of substrate). Above severities of 5, fermentation was inhibited in both straw and husk. In addition to inhibitors, high levels of cellulase-inhibiting xylo-oligomers and xylose were found and at much higher concentrations in rice husk liquor. At low severities, organic acids and related intracellular metabolites were released into the liquor.CONCLUSIONS:Rice husk recalcitrance to saccharification is probably due to the much higher levels of lignin and, from other studies, likely high levels of silica. Therefore, if highly polluting chemical pre-treatments and multi-step biorefining processes are to be avoided, rice husk may need to be improved through selective breeding strategies, although more careful control of pre-treatment may be sufficient to reduce the levels of fermentation inhibitors, e.g. through steam explosion-induced volatilisation. For rice straw, pre-treating at severities of between 3.65 and 4.25 would give a glucose yield of between 37.5 and 40% (w/DW, dry weight of the substrate) close to the theoretical yield of 44.1% w/DW, and an insignificant yield of total inhibitors.

Lodging continues to be a major cause of yield loss in important crop species such as Brassica napus. Understanding the genetic regulation of lodging resistance is therefore of key interest to breeders worldwide. Current strategies aimed at minimising lodging risk involve the incorporation of dwarfing genes or the application of plant growth regulators. However, despite these efforts, lodging continues to be a persistent problem and it is therefore of high interest that novel, complimentary strategies for lodging control are implemented. One approach would be to focus on understanding the genetic properties underlying stem mechanical strength. With this in mind, we screened a training genetic diversity panel of B. napus accession for variation in stem mechanical strength and related traits. Using Associative Transcriptomics, we identified molecular markers for a suite of valuable traits. Using an independent test genetic diversity panel, we show that the methods employed are robust for identification of predictive markers. Furthermore, based on conserved synteny with Arabidopsis thaliana, we are able to provide a biological context to the marker associations detected and provide evidence for a role in pectin methylesterification in contributing to stem mechanical strength in Brassicaceae.

BACKGROUND:Rice husk and rice straw represent promising sources of biomass for production of renewable fuels and chemicals. For efficient utilisation, lignocellulosic components must first be pretreated to enable efficient enzymatic saccharification and subsequent fermentation. Existing pretreatments create breakdown products such as sugar-derived furans, and lignin-derived phenolics that inhibit enzymes and fermenting organisms. Alkali pretreatments have also been shown to release significant levels of simple, free phenolics such as ferulic acid that are normally esterified to cell wall polysaccharides in the intact plant. These phenolics have recently been found to have considerable inhibitory properties. The aim of this research has been to establish the extent to which such free phenolic acids are also released during hydrothermal pretreatment of rice straw (RS) and rice husk (RH).RESULTS:RS and RH were subjected to hydrothermal pretreatments over a wide range of severities (1.57-5.45). FTIR analysis showed that the pretreatments hydrolysed and solubilised hemicellulosic moieties, leading to an enrichment of lignin and crystalline cellulose in the insoluble residue. The residues also lost the capacity for UV autofluorescence at pH 7 or pH 10, indicating the breakdown or release of cell wall phenolics. Saponification of raw RS and RH enabled identification and quantification of substantial levels of simple phenolics including ferulic acid (tFA), coumaric acid (pCA) and several diferulic acids (DiFAs) including 8-O-4'-DiFA, 8,5'-DiFA and 5,5'-DiFA. RH had higher levels of pCA and lower levels of tFA and DiFAs compared with RS. Assessment of the pretreatment liquors revealed that pretreatment-liberated phenolics present were not free but remained as phenolic esters (at mM concentrations) that could be readily freed by saponification. Many were lost, presumably through degradation, at the higher severities.CONCLUSION:Differences in lignin, tFA, DiFAs and pCA between RS and RH reflect differences in cell wall physiology, and probably contribute to the higher recalcitrance of RH compared with RS. Hydrothermal pretreatments, unlike alkali pretreatments, release cinnamic acid components as esters. The potential for pretreatment-liberated phenolic esters to be inhibitory to fermenting microorganisms is not known. However, the present study shows that they are found at concentrations that could be significantly inhibitory if released as free forms by enzyme activity.

AbstractThe sections in this article areIntroductionThe Location of Intercellular Cross‐Links within the WallThe Nature of Intercellular Polymers and Their Cross‐LinksConclusionsAcknowledgements

Plant cell wall materials derived from a range of waste biomass sources have great potential as a source of sustainable alternatives to petrochemicals. Perhaps the most straightforward way of realising this potential would be to hydrolyse the most efficiently fermentable polymers into their constituent sugars and use yeast to ferment these into useful chemicals. However, it also makes sense to pre-extract components which have a greater value in polymeric form. This is particularly true for non-cellulosic polymers, which are rich in poorly-fermentable pentose sugars. Liquid hot water (LHW) pretreatment can be used to extract non-cellulosic carbohydrates in a cost-effective manner, leaving a cellulose-rich substrate which is easier to hydrolyse using commercial cellulases. However, inherent differences in the plant cell wall structure and composition mean that some biomass sources may be more suitable for exploitation than others. Here, we examine eight different feedstocks (two each from hardwood, softwood, cereal straws and dicotyledonous crops), expose them to 26 different LHW pretreatment conditions and hydrolyse the entire pretreated slurry with a commercial cellulase. This enables side-by-side comparisons, in terms of saccharification yield, of the feedstocks. The results clearly demonstrate considerable differences in suitability between the feedstocks, in relation to the quantity of products released and the processes needed to obtain them.

Simo Sarkanen opened the discussion of the introductory lecture by Bruce Dale: The supposition that the strength of a national economy is directly related to energy consumption is incomplete. This hypothesis is reminiscent of Marx's suggestion that the value of an article is equivalent to the l

Yiping Luo opened the discussion of the paper by George W. Huber by asking: Did you carry out experiments using different ratios of water and solvent? Why did you choose the ratio 80 : 20? Also, regarding recovery of the lignin, after the experiment at 130 °C, is the structure of the lignin dif

This study compares in vitro and in vivo models of lipid digestion from almond particles within a complex food matrix (muffins) investigating whether the cell-wall barrier regulates the bioaccessibility of nutrients within this matrix. Muffins containing small (AF) or large (AP) particles of almond were digested in triplicate using an in vitro dynamic gastric model (DGM, 1 h) followed by a static duodenal digestion (8 h). AF muffins had 97.1 1.7% of their lipid digested, whereas AP muffins had 57.6 1.1% digested. In vivo digestion of these muffins by an ileostomy volunteer (0-10 h) gave similar results with 96.5% and 56.5% lipid digested, respectively. The AF muffins produced a higher postprandial triacylglycerol iAUC response (by 61%) than the AP muffins. Microstructural analysis showed that some lipid remained encapsulated within the plant tissue throughout digestion. The cell-wall barrier mechanism is the main factor in regulating lipid bioaccessibility from almond particles. (C) 2017 The Authors. Published by Elsevier Ltd.

Background: In Uganda, the chaff remaining from threshed panicles of millet and sorghum is a low value, lignocellulose- rich agricultural by-product. Currently, it is used as a substrate for the cultivation of edible Oyster mushrooms (Pleurotus ostreatus). The aim of this study was to assess the potential to exploit the residual post-harvest compost for saccharification and fermentation to produce ethanol.Results: Sorghum and millet chaff-derived spent oyster mushroom composts minus large mycelium particles were assessed at small-scale and low substrate concentrations (5% w/v) for optimal severity hydrothermal pre-treatment, enzyme loading and fermentation with robust yeasts to produce ethanol. These conditions were then used as a basis for larger scale assessments with high substrate concentrations (30% w/v). Millet-based compost had a low cellulose content and, at a high substrate concentration, did not liquefy effectively. The ethanol yield was 63.9 g/kg dry matter (DM) of original material with a low concentration (19.6 g/L). Compost derived from sorghum chaff had a higher cellulose content and could be liquefied at high substrate concentration (30% w/v). This enabled selected furfural-resistant yeasts to produce ethanol at up to 186.9 g/kg DM of original material and a concentration of 45.8 g/L.Conclusions: Spent mushroom compost derived from sorghum chaff has the potential to be an industrially useful substrate for producing second-generation bioethanol. This might be improved further through fractionation and exploitation of hemicellulosic moieties, and possibly the exploitation of the mycelium-containing final residue for animal feed. However, spent compost derived from millet does not provide a suitably high concentration of ethanol to make it industrially attractive. Further research on the difficulty in quantitatively saccharifying cellulose from composted millet chaff and other similar substrates such as rice husk is required.

James Clark opened the discussion of the paper by Keith W. Waldron: Regarding the point you made about ethanol, is that because it is flat-lining in terms of growth and demand? New bioethanol plants are being built, are they redundant before they are even complete? Keith Waldron