No abstract

Thermal-hydro-mechanical (THM) densification treatments were performed on Populus spp. (poplar), Picea abies (spruce), and Fagus sylvatica (beech). Prior to THM treatment, a low-molecular weight resin was impregnated into the wood structure. Densification results, mechanical characteristics (modulus of elasticity, rupture, and hardness), and set-recovery were assessed. All wood species were exposed to the same THM treatment and the specific anatomy, density, and physical behaviors yielded results specific to wood species making comparisons between species difficult. However, the mechanical performance of all samples was largely dictated by the specimens' surface density as seen in the density profiles. Spruce specimens had high levels of set-recovery after the THM treatment, which is believed to be caused by pit aspiration from kiln drying, limiting impregnation of the resin. The THM treatment used in this study was successfully applied to poplar, spruce, and beech. The resin impregnation combined with THM treatment led to densified wood with improved mechanical properties. The improvements were the greatest in poplar, including the largest reduction in setrecovery, which was the objective of this study. When comparing mechanical properties to commercially available structural wood-composites the results from this study indicate that resin impregnated THM treated wood could be used in this application.

A wet method and dry method of applying a soy flour (SF)-curing agent (CA) adhesive onto wood flakes were evaluated for making randomly oriented strandboard (R-OSB) and OSB. The wet method involved the thorough mixing of SF and CA prior to spraying the SF-CA mixture onto wood flakes. SF:CA weight ratio, adhesive add-on rate, hot-press conditions were optimized for enhancing internal bond strength (IB), modulus of rupture (MOR), and modulus of elasticity(MOE) of the resulting R-OSB. The highest IB, MOR and MOE were obtained at the 1:1 SF:CA weight ratio. IB, MOR and MOE of R-OSB exceeded the minimum industrial requirements at a C7% adhesive add-on rate, a hot-press temperature in the 170-220°C range, and a C4 min hot-press time. The dry method involved spraying aqueous CA solution onto a mixture of SF and wood flakes. The dry method allowed the strengths of the resulting R-OSB to exceed the minimum industrial requirements at a higher SF:CA ratio (up to 7:1). The dry method was superior to the wet method because a higher SF:CA ratio meant a lower adhesive cost. OSBs made with the SF-CA adhesive had strengths higher than or comparable to commercial OSBs.

No abstract

The conversion of raw fruits and vegetables, including tomatoes into processed food products creates side streams of residues that can place a burden on the environment. However, these processed residues are still rich in bioactive compounds and in an effort to valorize these materials in tomato by-product streams, the main aim of this study is to extract proteins and identify the main phenolic compounds present in tomato pomace (TP), peel and skins (TPS) by HPLC-DAD-ESI-QTOF. Forty different phenolic compounds were identified in the different tomato extracts, encompassing different groups of phenolic compounds, including derivatives of simple phenolic acid derivatives, hydroxycinnamoylquinic acid, flavones, flavonones, flavonol, and dihydrochalcone. In the crude protein extract (TPE) derived from tomatoes, most of these compounds were still present, confirming that valuable phenolic compounds were not degraded during food processing of these co-product streams. Moreover, phenolic compounds present in the tomato protein crude extract could provide a valuable contribution to the required daily intake of phenolics that are usually supplied by consuming fresh vegetables and fruits.