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In the Pacific Northwest United States, cereal crops (barley, oats, wheat) are the foundation of most dryland crop rotations. Nearly 100% of cereal producers use neonicotinoid seed treatments to manage wireworms, regardless of crop and pest density. However, wireworms cause variable damage to different crops, and whether neonicotinoids boost yield and economic returns across crops remains largely unknown. In a field experiment conducted on one commercial farm over two years, we examined effects of imidacloprid seed treatments on wireworm density, yield, and economic returns for barley, oat, and wheat crops. Wheat plots with imidacloprid seed treatments produced greater yields and economic returns over costs than untreated plots, even though wireworm densities were largely unaffected by treatments. However, no differences in yield and economic returns were observed between treatments in barley or oats. Wireworm densities were markedly lower in oats compared to barley and wheat, indicating not all crops provided a permissive environment for wireworms. Our results support the hypothesis that growers may benefit from moving away from applying seed treatments in all cereal crops, but rather targeting management to specific crops, although research at more commercial farm sites remains needed to test the generality of this conclusion. Our results also support the hypothesis that incorporating more tolerant cereal crops (barley and oats) into rotations to replace spring wheat may be a promising option for growers in areas with high wireworm pressure. • Imidacloprid increased yields and economic returns of wheat crops. • No yield differences in the control or treated plots in barley and oats were observed. • Wireworm densities were not affected by imidacloprid treatments. • Wireworm densities were lower in oats compared to barley and wheat. • Neonicotinoid seed treatments should only be targeted to susceptible crops. [ABSTRACT FROM AUTHOR]

Abstract This work aimed to model the effect of heat treatment on viscosity of milk protein concentrate (MPC) using kinetic data. MPC obtained after ultrafiltration was subjected to different time-temperature heat treatment combinations. Heat treatment at high temperature and short time (i.e., 100 or 120 °C×30 s) led to a significant increase in viscosity in MPC systems. Second-order reaction kinetic models proved a better fit than zero- or first-order models when fitted for viscosity response to heat treatment. A distinct deviation in the slope of the Arrhenius plot at 77.9 °C correlated to a significant increase in the rate of viscosity development at temperatures above this, confirming the transition of protein denaturation from the unfolding to the aggregation stage. This study demonstrated that heat-induced viscosity of MPC as a result of protein denaturation/aggregation can be successfully modelled in response to thermal treatment, providing useful new information in predicting the effect of thermal treatment on viscosity of MPC. Highlights • Heat treatment (≥75 °C) caused a significant increase in viscosity of MPC. • A model was developed to describe the effect of heat treatment on MPC viscosity. • Second-order kinetics proved a good fit for viscosity response to heat treatment. • The Arrhenius plot showed the transition from protein unfolding to aggregation. [ABSTRACT FROM AUTHOR]

Acid whey (AW) is the liquid co-product arising from acid-induced precipitation of casein from skim milk. Further processing of AW is often challenging due to its high mineral content, which can promote aggregation of whey proteins, which contributes to high viscosity of the liquid concentrate during subsequent lactose crystallization and drying steps. This study focuses on mineral precipitation, protein aggregation, and lactose crystallization in liquid AW concentrates (~55% total solids), and on the microstructure of the final powders from 2 independent industrial-scale trials. These AW concentrates were observed to solidify either during processing or during storage (24 h) of pre-crystallized concentrate. The more rapid solidification in the former was associated with a greater extent of lactose crystallization and a higher ash-to-protein ratio in that concentrate. Confocal laser scanning microscopy analysis indicated the presence of a loose network of protein aggregates (≤10 μm) and lactose crystals (100-300 μm) distributed throughout the solidified AW concentrate. Mineral-based precipitate was also evident, using scanning electron microscopy, at the surface of AW powder particles, indicating the formation of insoluble calcium phosphate during processing. These results provide new information on the composition- and process-dependent physicochemical changes that are useful in designing and optimizing processes for AW. [ABSTRACT FROM AUTHOR]

The effect of pH, adjusted using either hydrochloric acid (HCl), citric acid or sodium hydroxide, on calcium ion (Ca 2+ ) activity, and consequent changes in viscosity and heat coagulation time (HCT) of milk protein concentrate (MPC) was investigated. Reducing the pH of MPC dispersions resulted in a reduction in their viscosity, which subsequently increased during heat treatment. The maximum heat stability of MPC was observed at pH 6.7. Reducing the pH of MPC from 6.7 to 6.2 resulted in a significant ( P < 0.05) increase in Ca 2+ activity, and reduction in HCT. Such changes were more extensive using HCl compared with citric acid. Increasing the pH greater than 6.7 also led to a reduction in HCT but a decrease in Ca 2+ activity. These results demonstrate the importance of pH adjustment, and choice of acidulant, on Ca 2+ activity, viscosity, and heat coagulation properties of MPC concentrates during processing. [ABSTRACT FROM AUTHOR]

The effects of heat treatment and protein standardisation on the physical properties of skim milk concentrates were determined. Protein standardisation was carried out by the addition of lactose or milk permeate to skim milk. Unstandardised and standardised skim milk was subjected to heat treatment temperatures of 90 or 120 °C prior to evaporation whereafter the solids content was increased to 46% (w/w). Viscosity data showed non-standardised concentrates had the highest viscosity, followed by skim standardised with milk permeate followed by that standardised with lactose. Thermal treatment at 120 °C also resulted in a higher viscosity than that at 90 °C for all concentrates. Particle size data of evaporated skim milk showed a bimodal size distribution for skim milk standardised with liquid milk permeate, compared with monomodal distribution profiles for unstandardised skim milk and lactose standardised skim milk. Overall, this study showed that protein standardisation and standardisation media significantly affected concentrate properties. [ABSTRACT FROM AUTHOR]

Concern is expressed in the literature that as agriculture industrializes, regionality is lost; and with it, social, economic and environmental benefits. The example of oats in western Washington provides an opportunity to examine forces driving agricultural evolution during the twentieth century and to reflect on whether and to what degree they reveal changes in the extent and nature of regionality in agriculture over time. Research based on historic literature explores five themes which highlight different ways in which the disappearance of the oat crop from western Washington was associated with the decline of regionality in its agriculture. Whereas regionally grown oats as horse feed were once an important energy source for transport and machinery in western Washington, they have been superseded by fossil fuels following mechanization. Oats were eclipsed in importance as livestock and poultry feed by corn and soy, preferred by a professionalized animal feed production industry and better supported by agricultural policy and research. Regional milling operations for food oats have also given way to industrial scale production in national centers. Increased need for farmers to participate in the monetized economy drove them away from the small grains, whose market value has declined as their commoditization progressed. Lastly, the role of oats as an agronomic tool for weed and disease control was undermined by crop protection chemicals. Oats thus exemplify evolution away from regional self sufficiency and towards greater integration with national and global markets by western Washington farmers. While the process was in part compelled by wider developments in agriculture and industry, it was also self-driven: regional farmers and agriculture sector leaders embraced opportunities to grow cash crops and participate in national and global markets from an early stage of western Washington's agricultural history. In a more recent phase of agricultural evolution, social interest in and consumer demand for local and regional agriculture are growing. This phase represents deliberate choice of regionality in the knowledge that it is neither necessary for farmers nor the cheapest possible option for consumers. Reinvented roles for oats are becoming possible in the present context and demonstrate a new and more purposeful approach to regionality which leverages technology and the market. [ABSTRACT FROM AUTHOR]

Abstract: Consumer demand regarding the impacts of conventional agriculture on the environment and human health have spurred the growth of organic farming systems; however, organic agriculture is often criticized as low-yielding and unable to produce enough food to supply the world''s population. Using wheat as a model crop species, we show that poorly adapted cultivars are partially responsible for the lower yields often found in organic farming systems when compared with conventional farming systems. Our results demonstrate that the highest yielding soft white winter wheat genotypes in conventional systems are not the highest yielding genotypes in organic systems. An analysis of variance for yield among 35 genotypes between paired organic and conventional systems showed highly significant (P <0.001) genotype×system interactions in four of five locations. Genotypic ranking analysis using Spearman''s rank correlation coefficient (R S) showed no correlation between genotypic rankings for yield in four of five locations; however, the ranks were correlated for test weight at all five locations. This indicates that increasing yield in organic systems through breeding will require direct selection within organic systems rather than indirect selection in conventional systems. Direct selection in organic systems produced yields 15%, 7%, 31% and 5% higher than the yields resulting from indirect selection for locations 1–4, respectively. With crop cultivars bred in and adapted to the unique conditions inherent in organic systems, organic agriculture will be better able to realize its full potential as a high-yielding alternative to conventional agriculture. [Copyright &y& Elsevier]

Pea protein isolate (PPI) is used in many food formulations, due to its low cost, commercial availability and excellent amino acid profile. The objective of this study was to determine the emulsification properties of PPI. Particle size of PPI powders showed neither temperature (25–65 °C) nor time (up to 24 h) increased solubilisation of powder particles during mixing. Heating PPI dispersions (10%, w/w, protein) from 45 to 90 °C led to an increase in storage modulus ( G ′; Pa) at 71 °C, indicating the onset of protein aggregation. Gel formation occurred at 79 °C ( G ′ > 1 Pa). Pea protein-stabilised emulsions made using homogenization (15 MPa; 1 pass) or microfluidization (50 MPa; 1 pass) resulted in the formation of cold-set gels, with gel strength increasing with increasing oil concentration and fluidic pressure. Droplet size and viscosity of pea protein-stabilised emulsions decreased and increased, respectively, with increasing ultrasonication time. Overall, ultrasonication (< 50 °C) can create a uniform droplet size emulsion, while, homogenization and microfluidization can produce cold-set gels for use in a wide-range of food applications. [ABSTRACT FROM AUTHOR]

Sequential heating processes are commonly applied to milk by the dairy industry as part of their microbiological control strategy. Often pasteurisation at 72 °C is followed by a sequential high heat treatment step of up to 125 °C; however, such severe heat treatment can lead to reduced protein quality. Nine temperature combinations (80–90 °C) were evaluated to assess microbial reduction and whey protein nitrogen index values during pilot scale milk processing. A total of 110 bacterial isolates were identified to species level by 16S rDNA sequencing, with Bacillus licheniformis identified as the dominant species. While the experimental treatments did not achieve microbial reductions comparable with the control heating process, the results of this study provide a benchmark for milk processors relative to the effects of sequential heat treatments on milk and their impact on the survival of both thermally resistant microbial populations and thermally labile milk components during processing. [ABSTRACT FROM AUTHOR]

• Tested 8 grain crop sequences, some with quinoa, for dryland organic production. • Efficient N cycling through crop residues maintained soil N supply. • Inorganic N was higher in soil after quinoa compared to wheat. • Arbuscular mycorrhizal fungi colonized quinoa roots, but less than in other crops. • 3 years of organic grain production were supported by previous 5 years of alfalfa. Organic management is rapidly expanding as an alternative to conventional agriculture, but maintaining sufficient available soil nitrogen (N) supply is a challenge for organic systems in the semiarid regions of the US Pacific Northwest (PNW). Quinoa (Chenopodium quinoa Willd.) is a potential new crop for such systems, but there are many knowledge gaps regarding impacts of quinoa in crop rotations in the US. Here we tested the effects of quinoa in organic crop rotations for the Palouse region of the PNW. Specifically, we evaluated eight 3-year grain crop sequences, as part of a longer rotation with alfalfa, on the following metrics: crop productivity, soil N budgets, soil microbial parameters, arbuscular mycorrhizae, and soil aggregate size distribution. Organic crop yields averaged 495, 2736, and 2403 kg ha−1 for chickpea, barley, and wheat, respectively (33 %, 79 % and 77 % of the respective crop county averages). Yields were affected by weather across growing seasons, as were the amount and quality of residues, which in turn influenced soil N cycling. Overall soil N supply decreased slightly through the 3-yr sequences. Cereal grain yields were correlated with inorganic N (IN), and the correlation was stronger for subsurface (30−150 cm) depths than the surface (0−30 cm); IN was sufficient to support high cereal yields even in the later years when weather was suitable, but cereal yields overall may have been N-limited. Crop yields were more highly correlated with spring surface soil potentially mineralizable N than with spring surface IN. More inorganic N was available in surface (0−30 cm) post-harvest soil following quinoa (13.1 kg N ha-1 more) compared to wheat, but quinoa yields were low, with a 4-yr average of 104 kg ha−1. Soil microbial biomass and activity were not affected by sequence treatments. Although plants of the family Amaranthaceae are often considered "non-mycorrhizal", moderate rates of arbuscular mycorrhizal fungi (AMF) colonization were observed in quinoa. However, AMF colonization was lower in quinoa compared to other grains in the sequences, and the colonization of crops following quinoa was lower than following wheat. Soil structure was finer after quinoa, with a higher proportion of aggregates in the smaller size classes. Our results show that quinoa affects soil properties, and that organic management of 3-yr dryland grain sequences in rotation with alfalfa are possible in this area, given efficient N cycling through crop residues. [ABSTRACT FROM AUTHOR]

• Tested 8 grain crop sequences for dryland organic agriculture, some with quinoa. • Crop sequence affected agronomic outcomes but weather caused greater differences. • Economic returns from organic quinoa were moderate despite low yields. • Using alfalfa in organic grain cropping systems can increase profits & reduce risk. • Organic cropping systems financially outperformed a typical conventional system. Volatile crop prices and a desire for sustainability have farmers considering alternative practices to increase revenue diversity and protect soil health. Organic management is rapidly expanding as an alternative to conventional agriculture, and quinoa (Chenopodium quinoa Willd.) is a potential new crop for organic systems in the Pacific Northwest. Here we tested the agronomic and economic effects of diversifying dryland crop rotations with organic quinoa in the Palouse region of the Pacific Northwest. Eight 3-year grain cropping sequences were compared based on metrics of crop productivity, crop quality, and economic performance. While the crop sequences affected these metrics, crop yields and quality were mediated primarily by weather across growing seasons. Cumulative yields were higher for crop sequences that started with chickpea compared to barley. Organic quinoa yields were lower than the yield potential for the region, but some 3-year sequences with quinoa produced similar net returns to some sequences with wheat. Mean returns over variable costs were $324 ha−1 yr−1 for the 3-year sequence treatments; each treatment averaged positive net returns to variable costs despite some individual years having negative returns. The highest net returns to variable costs were in sequences that grew wheat and those that started with chickpea. Returns over total costs for the 3-year sequence treatments averaged -$33 ha−1 yr−1. The organic cropping systems (the total 8-year crop rotations including 5 years of organic alfalfa) produced higher returns over variable and total costs ($615 ha−1 yr−1 and $168 ha−1 yr−1, respectively) than a typical conventional rotation with county average yields during the same 8-year period ($477 ha−1 yr−1 and $82 ha−1 yr−1). Our results show that premiums for organic alfalfa and grains make these organic cropping systems economically viable for dryland production in the Pacific Northwest. Advances in organic weed control and regionally adapted quinoa varieties would further reduce the risk for farmers attempting this cropping system diversification. [ABSTRACT FROM AUTHOR]