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Replacing postharvest moisture loss in carrots (Daucus carota L., `Caro-choice') by single and repeated recharging (rehydration in water) treatments, interaction between the duration of recharging and temperature during recharging, and the effects of these treatments on moisture loss during subsequent short-term storage were studied. Carrot mass gain increased with increase in duration of single recharging treatments. Carrots that had lost 2.96% of their mass during storage at 13 °C and 35% relative humidity regained as much as 83% of the mass during recharging for 12 hours. Longer rechargings had little additional effect. Recharging at 13 °C and 26 °C was more effective at replacing water than at 0 °C. The rate of moisture loss (percent per day) during subsequent storage was not affected by recharging duration and temperature during recharging. With repeated recharging every 3.5 days, increase in recharging duration up to 9 hours increased carrot mass gain. Most of the mass gain occurred following 0 to 7 days of storage. These treatments, however, did not affect the rate of moisture loss during subsequent storage. These results suggest that the beneficial effect of recharging on carrot quality is due to replacement of the lost moisture and not to a decrease in moisture loss during storage following recharging. Abrading increased mass loss in non-recharged carrots and increased mass gain during recharging. Recharging should be explored as an option to improve the shelf life of carrots.

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The splitting of sweet cherry (Prunus avium L.) just before harvest can be a considerable problem in the Okanagan Valley (BC, Canada). In an attempt to minimize economic losses, growers apply a commercial cherry cuticle supplement in anticipation of a rainfall event. However, it is unknown if this product affects flavor, texture (crispness, firmness, and juiciness), or visual characteristics (stem browning, pitting, and pebbling) of sweet cherry. Therefore, this research was undertaken to evaluate the effects of a cherry cuticle supplement on the sensory, physicochemical, and visual characteristics of ‘Skeena’ sweet cherry. Firmness measurements were assessed with a fruit-firmness tester, whereas sensory determinations were assessed at first bite (whole-cherry crispness) and after multiple chews (flesh firmness) by a panel of 14 trained panelists. Fruit treated with the cherry cuticle supplement had lower instrumental firmness compared with the control, which was most pronounced after 28 days, with a reduction of 0.53 N. Treated fruit also had significantly lower sensory firmness and higher juiciness than the control fruit. Fruit treated with the cherry cuticle supplement had reduced water loss, less pitting, and lower stem-pull force, resulting in higher frequency of detachment of the stems. Further research would be necessary to evaluate the effects with other cultivars, and in years with rainfall events, as well as when hydrocooling is used.

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A convenient and reliable method that used a specially designed tool to apply a uniform bruising force in situ was developed to assess the relative susceptibility to fruit surface pitting in sweet cherry. Assessment of pitting with a visual scale after 2 weeks of 1 °C storage was found to be in close agreement with measurements of pit diameter. Using this method `Bing' showed the greatest susceptibility to pitting in both years of the study and `Bing', `Lapins', and `Sweetheart' cherries showed a decline in susceptibility as fruit matured. The predictive value of fruit firmness at harvest, fruit respiration at harvest, and weight loss in storage was assessed in relation to the severity of pitting. The model to best describe pitting was found to include all three physiological variables (firmness, respiration, and weight loss). While an acceptable model was obtained when combining all three cultivars, the best models were achieved when each cultivar was considered separately. It was concluded that there are likely unmeasured variables involved in determining susceptibility to pitting. Hence the best approach to predicting pitting susceptibility is the application of the pit-induction method described in this work.

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Apple fruits (Malus domestica Borkh. cv. Braeburn) harvested from two orchards (A and B) on the same day were stored in air or pretreated in air for 0, 2 (2dCA) or 4 weeks (4dCA) before moving into controlled atmosphere (CA) storage with 1.5% O2 + 5% CO2. During storage at 1 °C for 9 weeks in air and/or CA, changes of pyruvate decarboxylase (PDC) activity, alcohol dehydrogenase (ADH) activity, acetaldehyde (AA) and ethanol (EtOH) concentrations in flesh tissue were assayed in addition to the incidence of Braeburn browning disorder (BBD). Immediate introduction to CA conditions induced the development of BBD with the highest incidence 62.2%, however delaying application of CA for 2 and 4 weeks reduced the incidence of BBD to 38.5% and 27.0%. The development of disorder in grower B was less than in grower A. 2dCA and 4dCA treatments did not influence PDC activity compared with treatment of CA. However, ADH activity and the accumulation of AA and EtOH in treatments of 2dCA and 4dCA were markedly lower than those in CA. The accumulation of AA in grower B was lower than grower A. The results of this study suggest that the delayed application of CA reduced BBD and this may be due to reduced anaerobic metabolism of fruits in the delayed CA.

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The market value of the apple (Malus ×domestica Borkh.) cultivar Ambrosia is closely linked to the characteristic blush on the skin surface. For ‘Ambrosia’ orchards that produce consistently low levels of surface blush, the implementation of reflective rowcovering has improved surface coloration, but the reflected wavebands responsible for this enhanced color production have not been confirmed. This study consisted of two separate experiments: one conducted in the field to confirm reflective rowcovering efficacy and the other in a controlled environment cabinet to determine which waveband was enhancing red blush production. The red blush production in orchards with and without reflective rowcovering was then directly compared with the red blush produced on the surface of apples that were poorly colored at harvest and then exposed to visible, fluorescent, ultraviolet A (UVA), or ultraviolet B (UVB) light sources within the controlled environment chamber. Consequent analysis of the red blush color within the Commission Internationale de l’Eclairage a* and b* color space was conducted to evaluate the quality of the red blush pigment under each treatment in the field and the controlled environment chamber. The analysis revealed that the red blush that developed on apples from the reflective rowcover treatment most closely matched the red blush that developed in response to UVB exposure in the controlled environment cabinet. Further analysis of gene expression and anthocyanin contents in the ‘Ambrosia’ apples support the hypothesis that the primary driver for the characteristic red blush development, when reflective rowcovers are used, is increased exposure to UVB light.

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