Benoit Girard

Antimicrobial activity of individual and mixed fractions of dill, cilantro, coriander and eucalyptus essential oils.

Essential oils from dill (Anethum graveolens L.), coriander (seeds of Coriandrum sativum L.), cilantro (leaves of immature C. sativum L.) and eucalyptus (Eucalyptus dives) were separated into heterogeneous mixtures of components by fractional distillation and were analyzed by gas chromatography-mass spectroscopy. Minimum inhibitory concentrations against gram-positive bacteria, gram-negative bacteria and Saccharomyces cerevisiae were determined for the crude oils and their fractions. Essential oil of cilantro was particularly effective against Listeria monocytogenes, likely due to the presence of long chain (C6-C10) alcohols and aldehydes. The strength and spectrum of inhibition for the fractions often exceeded those determined in the crude oils. Mixing of fractions resulted in additive, synergistic or antagonistic effects against individual test microorganisms.

Characteristics of raspberry (Rubus idaeus L.) seed oil

Abstract Studies were conducted on properties of oil extracted from raspberry seeds. Oil yield from the seed was 10.7%. Physicochemical properties of the oil include: saponification number 191; diene value 0.837; p-anisidine value 14.3; peroxide value 8.25 meq/kg; carotenoid content 23 mg/100 g; and viscosity of 26 mPa.s at 25°C. Raspberry seed oil showed absorbance in the UV-B and UV-C ranges with potential for use as a broad spectrum UV protectant. The seed oil was rich in tocopherols with the following composition (mg/100 g): α-tocopherol 71; γ-tocopherol 272; δ-tocopherol 17.4; and total vitamin E equivalent of 97. The oil had good oxidation resistance and storage stability. Lipid fractionation of crude raspberry seed oil yielded 93.7% neutral lipids, 3.5% phospholipids, and 2.7% free fatty acids. The main fatty acids of crude oil were C18:2 n-6 (54.5%), C18:3 n-3 (29.1%), C18:1 n-9 (12.0%), and C16:0 (2.7%). The ratio of fatty acids, polyunsaturates to monounsaturates to saturates varied depending on lipid fraction. Polymorphic changes were observed in thermal properties of raspberry seed oil.

Influence of membrane structure on fouling layer morphology during apple juice clarification

The flux behavior of 0.2 μm nylon, polysulfone (PS), polyvinylidene fluoride (PVDF) and polyethersulfone (PES) membranes was examined during dead-end microfiltration of commercial apple juice. On nylon membranes, a 0.1 μm thick surface fouling layer rapidly formed that acted as a secondary membrane. The colloidal particles retained by this surface layer aggregated to form a thick loose gel structure, producing an anisotropic fouling structure. In contrast, the 4 μm thick surface fouling layer of PES was slower to form and had a more open structure with a lower flux resistance per unit thickness. The morphology of the PES surface layer also did not differ dramatically from the loose gel structure that subsequently formed on top of this secondary membrane. The PS surface fouling layer was similar in structure to nylon whereas the PVDF layer more closely resembled that found with PES. The density of the surface fouling layer did not directly correlate to membrane surface hydrophobicity or pure water flux. Atomic force microscopy (AFM) indicated that surface roughness strongly influenced surface fouling layer morphology. The membrane surface appears to act as a template for the fouling process; therefore, smooth membranes (nylon and PS) produce a dense surface fouling layer whereas this same layer on rough membranes (PES and PVDF) is much more open. Consequently, the fluxes of PES and PVDF membranes are less affected by fouling formation.

Vinification effects on the sensory, colour and GC profiles of Pinot noir wines from British Columbia

Abstract Analytical and sensory profiles were obtained for Pinot noir wines fermented with two yeasts (Lalvin EC-1118, P; Lalvin L-2056, L) and four vinification techniques: high (T), ambient, cold and modified-cold temperature (M) fermentations. Wines were analysed for titratable acidity, pH, ethanol, colour, total phenolics, flavonols, tartaric esters, anthocyanins and volatile constituents. Sensory descriptive analysis was conducted using 12 judges to evaluate colour, aroma, flavour, body and overall quality. Wines from the M vinification had the most red colour, body, tropical fruit and spicy aromas and had the least vegetal character. Wines from the T vinification were the most vegetal. Increased ester concentration (mainly acetates) and total volatile compounds were found in wines from the M vinification with yeast P in comparison to the other vinification methods and yeast L. Principal component analyses distinguished four distinct groups of wines based on 33 main volatile constituents. Partial least square regressions revealed strong relationships between sensory and instrumental colour measurements in terms of red colour intensity ( r =0.88) and red hue ( r =0.87).

Modified atmosphere packaging of ‘Lapins’ sweet cherry

Abstract ‘Lapins’ sweet cherries ( Prunus avium L.) were stored at 0 °C under modified atmospheres for 10 weeks. Atmospheres within low density polyethylene bags of 38 μ thickness equilibrated to 0.8% O 2 and 4.5% CO 2 by the second week of storage. Brightness of the fruit ( L values) declined after 6 weeks and firmness decreased after 8 weeks. Titratable acidity declined steadily over the storage period. Stems remained green during the 10-week storage period. Sixty volatile compounds were isolated by a purge and trap method. Two principal components (PC) accounted for 73.5% of the total variation in volatile production. PCI accounted for the variation between the first 6 weeks of storage and weeks 8–10 and PC2 accounted for the variation between weeks 8 and 10. The variation in volatiles involved aldehydes, alcohols, ketones and esters. Sensory evaluation by a trained panel revealed a significant decline ( P ≤ 0.05) in external appearance with each sampling date relative to all previous sampling dates. Flavour also declined in value with each removal date except for week 1 which did not differ from that at harvest. Texture after two weeks of storage was perceived as crunchier and did not change with subsequent removal dates. Off flavours were present at week 8. Acceptability remained high for 4–6 weeks of storage but decreased appreciably thereafter.

Development and evaluation of multiple regression models for prediction of sweet cherry liking

Abstract In two experiments, multiple regression models were developed and evaluated to identify the relevant sensory attributes for cherry liking. In Experiment 1, 16 judges evaluated 18 cherry varieties for seven visual characteristics (colour intensity, uniformity-of-colour, speckles, size, stem length, external firmness and ‘visual’ liking) and seven flavour/texture characteristics (flesh firmness, flesh colour intensity, juiciness, sweetness, sourness, flavour intensity and ‘flavour/ texture’ liking). Stepwise multiple regression was used to develop the most appropriate statistical models for prediction of visual and flavour/texture liking based on visual and flavour/texture characteristics, respectively. Both models were simple and easily understandable with two sensory variables. The best model for visual liking required only size and uniformity-of-colour variables; whereas, the best model for flavour/texture liking required sweetness and flavour intensity variables. In Experiment 2, 18 judges evaluated 30 sweet cherry cultivars, using the same methodology, to create a validation data set. Correlation coefficients ( R ) and prediction standard errors (PSEs) between the observed (Experiment 2) and predicted (Experiment 1) liking scores were used to evaluate the prediction equations. The prediction equation for flavour/texture liking was most satisfactory ( R = 0.85, PSE = 0.61). A new equation developed from the validation data confirmed the importance of sweetness and flavour intensity. In contrast, the prediction equation for visual liking was less satisfactory ( R = 0.56) and a new equation developed from the validation data set confirmed only size as an important variable.

Effect of maturity and storage on quality and volatile production of ‘Jonagold’ apples

Abstract ‘Jonagold’ apples ( Malus domestica Borkh.) harvested 3 times at bi-weekly intervals starting approximately two weeks prior to commercial harvest were stored at 0 °C in air and controlled atmosphere (CA, 1.5% O 2 + 1.5% CO 2 ) for six months. Starch index (SI) increased from 2.1 to 8.4 during the harvest period. Early harvests and CA significantly ( P ≤ 0.05) reduced the loss of acidity and firmness in stored apples but did not influence total soluble solids content. CA decreased the volatile production (esters, alcohols, and hydrocarbons) by half. The last harvest (SI = 8.4) provided an increase of 14% in volatiles compared to the first date (SI = 2.1). These increases were mostly due to straight C3–C6 chain acetates and alcohols, and the hydrocarbon α-farnesene. Variation in background skin colour within the same harvest period had a negligible effect on volatile patterns. Harvest at starch index values of 6.5–8.5 allowed higher concentration of odour-active compounds while retaining acceptable levels of acidity and firmness.

Enabling a sustainable and prosperous future through science and innovation in the bioeconomy at Agriculture and Agri-Food Canada

Science and innovation are important components underpinning the agricultural and agri-food system in Canada. Canadas vast geographical area presents diverse, regionally specific requirements in addition to the 21st century agricultural challenges facing the overall sector. As the broader needs of the agricultural landscape have evolved and will continue to do so in the next few decades, there is a trend in place to transition towards a sustainable bioeconomy, contributing to reducing greenhouse gas emission and our dependency on non-renewable resources. We highlight some of the key policy drivers on an overarching national scale and those specific to agricultural research and innovation that are critical to fostering a supportive environment for innovation and a sustainable bioeconomy. As well, we delineate some major challenges and opportunities facing agriculture in Canada, including climate change, sustainable agriculture, clean technologies, and agricultural productivity, and some scientific initiatives currently underway to tackle these challenges. The use of various technologies and scientific efforts, such as Next Generation Sequencing, metagenomics analysis, satellite image analysis and mapping of soil moisture, and value-added bioproduct development will accelerate scientific development and innovation and its contribution to a sustainable and prosperous bioeconomy.