Do organisational and environmental factors moderate the effects of Internet-based interorganisational systems on firm performance?

We developed a model of the relationships among several organisational, interorganisational and technological factors, the adoption of Internet-based interorganisational systems (IBIS) and various measures of firm performance. We used structural equation modelling to empirically test these relationships. The findings showed that adopting IBIS indirectly improves the operational performance of firms through business process performance. The positive effect on financial performance of adopting IBIS is not direct, but through the mediating effects of operational performance and business process performance. We also utilised multiple group analysis to test some of the model relationships across firms using several organisational and environmental factors as moderators. The organisational factors tested are firm type, age and ownership type. The environmental factors consisted of dynamism, complexity and hostility. We found that the organisational factors are significant moderators and that complexity and hostility are not significant moderators. However, the effects of dynamism as a moderator are less clear.     

Effect of high-pressure/high-temperature processing on chemical pectin conversions in relation to fruit and vegetable texture

Heat sterilization of plant derived food products entails considerable organoleptic and nutritional quality losses. For instance, texture loss of fruits and vegetables occurs, next to turgor pressure losses, mainly due to chemical changes in the cell-wall pectic polysaccharides. High-pressure sterilization, i.e. the combination of high temperature (?90 °C) with high pressure (?500 MPa), could present a positive alternative assuring safety while minimizing quality losses. In this study, the potential of high-pressure sterilization in preserving fruit and vegetable texture was evaluated by investigating the effect of combined high-pressure/high-temperature (HP/HT) treatments on two texture related chemical pectin conversions in model sytems. First, a protocol was developed to perform reproducible kinetic studies at HP/HT under constant processing conditions. Subsequently, apple pectin solutions at pH 6.5 were subjected to different HP/HT combinations (500, 600 and 700 MPa/90, 110 and 115 °C) and the extent of chemical demethoxylation and β-eliminative depolymerization was determined. At atmospheric pressure, both zero-order reaction rate constants increased with increasing temperature. At all temperatures, demethoxylation showed a higher rate constant than β-elimination. However, a temperature rise resulted in a stronger acceleration of β-elimination than of demethoxylation. When combining high temperature with high pressure, β-elimination was retarded or even stopped, whereas demethoxylation was stimulated. These results are very promising in the context of the texture preservation of high-pressure sterilized fruits and vegetables, as β-elimination is accepted to be one of the main causes of thermal softening and low methoxylated pectin can enhance tissue strength by forming cross-links with calcium ions present.     

Field demonstration of automated demand response for both winter and summer events in large buildings in the Pacific Northwest

There are growing strains on the electric grid as cooling peaks grow and equipment ages. Increased penetration of renewables on the grid is also straining electricity supply systems and the need for flexible demand is growing. This paper summarizes results of a series of field test of automated demand response systems in large buildings in the Pacific Northwest. The objective of the research was twofold. One objective was to evaluate the use demand response automation technologies. A second objective was to evaluate control strategies that could change the electric load shape in both winter and summer conditions. Winter conditions focused on cold winter mornings, a time when the electric grid is often stressed. The summer test evaluated DR strategies in the afternoon. We found that we could automate both winter and summer control strategies with the open automated demand response communication standard. The buildings were able to provide significant demand response in both winter and summer events.     

Effects of High-Pressure Pretreatment and Calcium Soaking on the Texture Degradation Kinetics of Carrots during Thermal Processing

ABSTRACT: Carrots ( Daucus carota ) pretreated under different high-pressure conditions were thermally processed at temperatures in the range of 90°C to 110°C. Texture degradation (hardness) was monitored objectively using a texture analyzer. For a given thermal treatment, the rate constant (k-value) decreased with increasing pretreatment pressure. A high-pressure pretreatment (200 to 500 MPa) at 60°C for 15 min resulted in a more pronounced texture improvement compared with the same pretreatment at 20°C and 40°C, respectively. Calcium impregnation conferred more beneficial effects when applied immediately after the high-pressure pretreat-ment. The observed changes in texture characteristics were associated with the degree of methylation of carrot pectins, which is dependent on pectinmethylesterase (PME) activity.     

Stress relaxation behaviour of moth bean flour dough: Product characteristics and suitability of model

Stress relaxation characteristics of moth bean (raw and roasted) flour doughs having different moisture contents were determined at two different strain levels (0.05 and 0.50). The decaying relaxation curves for raw flour showed an initial stress between 2 and 22 kPa when the moisture content varied from 28% to 34% at a strain of 0.05. Roasted flour doughs exhibited initial stresses between 0.06 and 2 kPa at moisture contents between 40% and 46%. Dough formation was not possible below 40% moisture content for roasted samples. An increase in moisture content markedly decreased initial and residual stresses. It is desirable that dough should possess a low value of residual stress when used for developing flattened/sheeted products. Models containing two or three parameters were found suitable for large-strain stress relaxation characteristics while low-strain data can be modelled by a 4-element Maxwell model with residual stress.     

Statistical analysis of baseline load models for non-residential buildings

Policymakers are encouraging the development of standardized and consistent methods to quantify the electric load impacts of demand response programs. For load impacts, an essential part of the analysis is the estimation of the baseline load profile. In this paper, we present a statistical evaluation of the performance of several different models used to calculate baselines for commercial buildings participating in a demand response program in California. In our approach, we use the model to estimate baseline loads for a large set of proxy event days for which the actual load data are also available. Measures of the accuracy and bias of different models, the importance of weather effects, and the effect of applying morning adjustment factors (which use data from the day of the event to adjust the estimated baseline) are presented. Our results suggest that (1) the accuracy of baseline load models can be improved substantially by applying a morning adjustment, (2) the characterization of building loads by variability and weather sensitivity is a useful indicator of which types of baseline models will perform well, and (3) models that incorporate temperature either improve the accuracy of the model fit or do not change it.     

Pectins in Processed Fruits and Vegetables: Part II—Structure–Function Relationships

ABSTRACT: Pectin represents a very heterogeneous biopolymer whose functionality remains largely puzzling. The link between the pectin fine structure and functional properties with relevance to plant growth and development, as well as food processing, is continually being explored. This review describes the current knowledge of pectin structure–function relationships. Key mechanisms dictating pectin structure–function relationships are discussed, including the polymer biosynthesis, cross‐linking mechanisms, enzymatic and nonenzymatic conversion reactions, solubility properties, and more. Insight into the polymer structure–function relationships is highlighted by examining traditional and advanced methodologies used in pectin research. The role of pectin in modulating the quality characteristics of plant‐based foods is underlined while pin‐pointing some of the main challenges and perspectives. An integrated approach using the pectin structure–function relationship in the precision engineering of mechanical properties of tissue‐based systems is proposed.     

Pectins in Processed Fruits and Vegetables: Part III—Texture Engineering

ABSTRACT: Current interest in controlling the textural and rheological properties of processed fruit and vegetable products has stimulated research on the biochemistry of the cell wall, with particular reference to pectin and its degradation. This review covers the literature over the last decade with respect to pectin engineering in the field of fruit and vegetable processing. Several applications, illustrating that refined manipulation of chemical and/or enzymatic pectin degradation can be used as a tool to improve the texture/rheology of thermally processed and frozen fruit and vegetable products, are described. The discussion includes an evaluation of the role of novel technologies such as high‐pressure processing in pectin engineering of processed fruits and vegetables. Furthermore, the possible role of pectin‐related enzymes other than pectin methylesterase (PME) and polygalacturonase (PG) and of the nontraditional, ferulic acid‐mediated cross‐linking process is discussed. Finally, new trends, challenges, and suggestions for future pectin engineering research are covered in this review.     

Rheological characterization of raw and roasted green gram pastes

Rheological properties of raw and roasted green gram pastes have been determined at different moisture contents (52–56 g/100 g) and temperatures (10–40 °C). These pastes exhibit shear-thinning behavior and possess yield stress. Cross model is suitable (0.986 ≤ r ≤ 0.999, p ≤ 0.01) to explain the flow characteristics of the pastes. The Cross model parameters such as zero-shear viscosity and relaxation time are sensitive to concentration of solids in the paste as well as temperature of measurement, and vary widely between raw and roasted samples. The effect of temperature on the apparent viscosity follows the Arrhenius type relationship (r ≥ 0.961, p ≤ 0.01). The viscoamylographic indices and trypsin inhibitor content are also different for raw and roasted samples. The roasted pastes show a smooth and cohesive microstructure. The optimized sample of roasted flour having a moisture content of 55 g/100 g is suitable as bread spread with appropriate stickiness and spreadability.     

The relation between (bio-)chemical, morphological, and mechanical properties of thermally processed carrots as influenced by high-pressure pretreatment condition

Thermal texture evolution kinetics (90–110 °C) of nonpretreated and high-pressure pretreated (HP = 400 MPa, 60 °C, 15 min) carrots were determined using a multiparameter approach (cutting, compression). Alcohol Insoluble Residues (AIR) were extracted before and after thermal processing of the samples and the degree of methylation (DM) was estimated. The β-elimination kinetics of the water soluble pectin extract from the AIR was studied and related to the changes in material properties. Morphological changes and tissue-failure characteristics were monitored. The mechanical properties were strongly dependent on the processing temperature and the DM of the samples. Texture degradation rate constants were independent of the texture measurement method. Increasing temperature accelerated the β-elimination reaction (k _b) and the thermosoftening (k _x) rates, but pretreatment condition slowed down the rates. Interestingly, a strong correlation (r > 0.99) between k _b and k _x occurred. Thermal processing resulted in cell-wall thickening accompanied by a transition from cell rupture to cell separation, a process retarded by pretreatment condition.