Fruit firmness is among the most important characteristics for the quality of sweet cherries. However, little has been published on its underlying frequency distribution. This research was undertaken to examine the firmness distributions (n = 48) from six cultivars [Sandra Rose, Summit, Lapins, Skeena, Sumtare (Sweetheart™), and 13S2009 (Staccato™)], two field treatments [with or without gibberellic acid (GA)], two storage times (0 and 7 days), and two growing seasons (2013 and 2014). Fruit was sampled (n = 300) at optimal maturity and firmness was evaluated using the FirmTech2 Fruit Firmness Tester. Firmness distributions were examined using descriptive statistics: mean, median, standard deviation (sd), minimum, maximum, range, skewness, and excess kurtosis. Nonnormality was assessed using skewness and kurtosis test statistics. Exponential models were fitted to the ascending and descending portions of the distributions and the proportion of “too soft” (percentage < 2.56 N·mm−1) and “too hard” (percentage > 4.71 N·mm−1) fruit was determined. A relatively high proportion of distributions were nonnormal (16/24 to 18/24), either skewed, peaked, or both. While most skewed distributions were skewed negatively, with a higher proportion of softer fruit, the distributions for ‘Sandra Rose’ were skewed positively, with a higher proportion of firmer fruit. Principal component analysis (PCA) showed seasonal, cultivar, treatment, and storage effects among three subsets of cultivars with differing characteristic firmness. The softer early-harvest cultivars (Sandra Rose and Summit) had a higher proportion of “too soft” fruit. GA and storage treatments increased mean firmness and reduced the proportion of “too soft” fruit. The firmer late-harvest cultivars (Skeena, Sumtare, and 13S2009) had a small proportion of “too hard” fruit (0% to 19.3%). The work gained insight into the nature of the firmness distributions for sweet cherries and the type of statistics that are most appropriate for analyzing the data.
Kareen Stanich, Margaret Cliff, and Cheryl Hampson
Margaret A. Cliff, Kareen Stanich, and Peter M.A. Toivonen
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.
Margaret Cliff, Katherine Sanford, Wendy Wismer, and Cheryl Hampson
This research used digital images to explore some of the factors responsible for consumer preference of visual characteristics of apples (Malus ×domestica Borkh.). The images systematically varied in color and shape (Expt. A: 9 images) and type, shape, and background color (Expt. B: 10 images), while keeping apple size constant. Visual assessments of the apple images were collected from 144 consumers (Expt. A) and 165 consumers (Expt. B) in British Columbia (BC), Nova Scotia (NS), and New Zealand (NZ) using balanced incomplete block designs. Canadian consumers (BC and NS) preferred red apples over green or yellow. NZ consumers liked equally red and green apples, and preferred both to yellow apples. At all locations, consumers in Expt. A significantly preferred round and conical shaped apples to oblong apples. When the combined effects of type, shape, and background color were evaluated, NZ consumers rated the striped, round apples the highest, and least preferred both round and oblong, blush-type apples with yellow backgrounds. NS consumers tended to prefer blush apples regardless of type and background color, and BC consumers were more accepting of a range of apple types, shapes, and background colors.
Andrew G. Reynolds, Margaret Cliff, Douglas A. Wardle, and Marjorie King
Eighty-five cultivars, selections and clones of winegrapes (Vitis) from European breeding and selection programs were evaluated between 1993–95 in a randomized completeblock experiment. These included selections from Alzey, Freiburg, Geilweilerhof, Geisenheim, Weinsberg, and Würzburg (Germany); Hungary; and the former USSR. Vines were grown under an organic management regime that included sodium silicate sprays for powdery mildew (Uncinula necator) control and oil + detergent for insect control but with little to no nitrogen or other nutritional inputs. The Weinsberg cultivars Heroldrebe and Helfensteiner showed promise viticulturally and sensorially as alternatives to `Pinot noir'. Cultivars from Geisenheim (`Gm 7117-10' and `Gm 7117-26') and Würzburg (`Cantaro' and `Fontanara') appeared promising as `Riesling' alternatives; many displayed similar sensory characteristics to `Riesling', along with reasonable viticultural performance. Cultivars selected at Alzey (`Faberrebe'), Freiburg (`Nobling'), and Weinsberg (`Holder') displayed sensory characteristics superior to the standard cultivar Müller-Thurgau, with very intense muscat, pear, fig, and spicy aromas and flavors. Several muscat-flavored Hungarian white wine cultivars appeared to be superior viticulturally and sensorially to the standard `Csabagyongye'; these included `Kozma Palne Muscotaly', `Zefir', and `Zengo'. Miscellaneous red wine cultivars that showed promise included Geilweilerhof cultivar Regent, and Hungarian selections Kozma 55 and Kozma 525. Vine yields decreased substantially in the 3-year evaluation period, primarily due to lack of nitrogen. Many of these cultivars appeared to be highly adaptable to viticultural regions where cold winters and low heat units during fruit maturation presently restrict cultivar choices.
Andrew G. Reynolds, Margaret Cliff, Douglas A. Wardle, and Marjorie King
Eighty-five cultivars, selections and clones from European winegrape (Vitis spp.) breeding and selection programs were evaluated between 1993 and 1995 in a randomized complete-block experiment. These included Vitis vinifera clones from France as well as Freiburg, Geisenheim, and Weinsberg, Germany. Small yield and fruit composition differences were found amongst the 'Chardonnay' clones. The standard Prosser clone produced wines with highest earthy aroma and acidity and with lowest perfumy aroma, body and finish; Dijon clones 76 and 96 were most perfumy and least vegetal. `Pinot noir' clones also differed somewhat in terms of yield and fruit composition; `Samtröt', `Gamay Beaujolais', and clone Q1342-01 were amongst the most highly colored clones. These clones also tended to have the most intense berry and currant aromas as well as berry, cherry, and currant flavors. These aforementioned clones appear to be highly adaptable to viticultural regions where low heat units during fruit maturation presently limit industry growth.