Ripening effects on the chilling sensitivity of processing and

J. Appl. Hort., 2(2):76-78, July-December, 2000 Ripening effects on the chilling sensitivity of processing andnon-processing tomato cultivars Department of Food Production, Faculty of Agriculture and Natural Sciences. The University of the West Indies,St. Augustine. Trinidad, West Indies Abstract
Studies on the sensitivity to chilling injury (CI) of 8 processing and 8 non-processing tomato cultivars stored at the table-ripe stagewere examined. Fruits were stored for 21 days at 7oC and upon transfer to 20oC for 1 or 3 days, respectively. The low correlationcoefficient between pitting and decay suggested that these two early manifestations of CI are not significantly related. The leastsensitive tomato cultivars to CI were Advantage, Dorado and Rio Grande among the processing types and Star Pak and Walters of thenon-processing types. The least tolerance to CI were processing cultivars Caraibe and Cascade and non-processing cultivars EarlySet, Carnival and Capitan. The observed tolerance of table-ripe tomatoes mentioned above after 21 days at 7oC plus 3 days at 20oCcompared to control fruit stored continuously at 20oC for only 8 -11 days, indicates that a longer marketing period could be obtainedat tempertures lower than those currently recommended.
Key words: Tomato, processing and non-processing cultivars, chilling injury, sensitivity
Capitan. Samples from all sixteen cultivars were ripened to table- Introduction
ripe stage, USDA score 6 (United Fresh Fruit and Vegetable Assn., Chilling injury (CI) is an economically important postharvest 1975), at 20-22oC and 85-90% RH over 3-4 days. Measurements problem that reduces the overall quality and marketability of many were made on five fruits per cultivar each time, i.e. after 21 days at harvested fruits and vegetables indigenous to the tropics and 7oC (SRI) and upon transfer to 20oC for 1 day (SR2) or 3 days subtropics (Couey, 1982, Saltveit and Morris, 1990; Cabrera and (SR3), respectively. Likewise, a similar portion of fruit per cultivar Salveit, 1992). The effect of storage temperature on chilling- induced quality changes in tomatoes (Lycopersicon esculentum, The severity of pitting and decay was determined subjectively on Mill.) varies with cultivar (Abou-Aziz et al., 1976), duration of a 8-point hedonic scale as previously described (Cabrera and storage (Hobson, 1981) and ripeness of the fruit (Autio and Saltveit, 1992). The scoring system was 0 = no pitting or decay Bramlage, 1986). Ripening-related changes in chilling sensitivity (0% of the fruit surface was pitted or decayed, 2 = slight (1% to are common among fruit species such as Honey Dew melons 5%), 4 = moderate (6% to 15%), 6 = severe (16% to 75%), and 8 = (Lipton, 1978), mangoes (Mukerjee and Srivastava, 1979, Mohammed and Brecht, 1999), and papayas (Nazeeb andBroughton, 1978). Most field-grown tomatoes are commercially Resistance of the fruit to chilling injury was ranked for each cultivar harvested at the mature-green stage and, thus, much of the previous on a scale of 1 - 10 with 1 = most susceptible and 10 = most resistant research on CI in tomatoes has been conducted with the mature- (Cabrera and Saltveit, 1992). The overall quality, based on the green fruit (King and Ludford, 1983; McColloch and Worthington general appearance of the fruit, was measured subjectively on a 8- 1952; Buescher, 1974; Thorne and Alvarez, 1982). The objective point hedonic scale where 0 = poor (extremely defective), 2 = fair of this study was to investigate the chilling sensitivity of several (defective), 4 = good (moderately defective), 6 = very good (slightly table-ripe processing and non-processing tomato cultivars.
defective), 8 = excellent (not defective).
Brown discolouration on fruit skin indicative of chilling injury was Materials and methods
scored on a 5-point hedonic scale where 0 = no discolouration, 1 =0- 10% discolouration, 2 = 11-20% discolouration, 3 = 21-40% Field-grown mature-green tomatoes, (Lycopersicon esculentum, discolouration, 4 = 41-60% discolouration and 5 = >60% Mill.) were hand-harvested at the University Field Station, Valsayn in the dry-season (May - April) and wet-season (July - September)of 1992. Maturity of mature-green fruit was determined in the Because of very small and insignificant differences between dry field using subjective evaluations of fruit size, position on plant, and wet season data, the mean for both the seasons were calculated smootheness of fruit shoulder and by observation of locular for each cultivar. Data were subjected to analysis of variance.
development in some representative fruit (Kader and Morris, 1975).
Eight processing cultivars, Dorado, Advantage, Peto 94C, Neema Results and discussion
1401, Caraibe, Rio Grande, Donore and Cascade were studied.
The severity of pitting depended on cultivar, ranging from 0.0 to The eight non-processing cultivars studied were Calypso, 6.7 in fruit stored for 21 days at 7oC and kept for an additional 1 or Floradade, Floradel, Early Set, Star Pak, Carnival, Walters and Chilling sensitivity of processing and non-processing tomato cultivars 3 days at 20oC (Table 1). Processing cultivars Advantage and Although quality of the non-processing cultivars Star Pak and non-processing cultivar Walters developed no pits after 21 days at Walters averaged the same as the processing cultivars Dorado, 7oC, while processing cultivars Dorado, Rio Grande and Donore Advantage, Rio Grande and Donore at SR1, quality evaluations at and non-processing cultivar Star Pak developed slight pitting under SR3 showed that Star Pak and Walters secured higher ratings than the same storage conditions (Table 1). The most pitted fruits were either of the 4 processing cultivars Advantage, Dorado, Rio Grande Peto 94C, Cascade, Neema 1401 and Caraibe (processing) as well as Calypso and Floradade (non-processing) with ratings being 3.4to 3.8. Likewise, non-processing cultivars Early Set, Carnival and The correlation between pitting and decay was lower (r = 0.44) Capitan had pits with ratings above 4.1 after 21 days at 7oC (Table than between decay and quality (r = 0.79). However, pitting is 1). Significant increases in pitting between storage regimes SR1 more closely related to fruit resistance to chilling and degree of and SR2 were obtained for 50% of the processing cultivars (Dorado, brown discolouration (r = 0.90 and 0.84, respectively) than it is to Peto 94C, Neema 1401 and Caraibe) and just 25% for non- decay (r = 0.46). A multiple regression analysis was performed processing cultivars Calypso and Floradel. However, between SR2 with the percent change in quality as the dependent variable and and SR3 pitting progressed significantly for all sixteen cultivars.
pitting, decay, fruit resistance to chilling injury and degree of browndiscolouration as the independent variables. The analysis produced Although decay followed a similar trend like pitting between each a coefficient of determination of 0.84, which suggested that quality storage regime (SR1, SR2 and SR3), the correlation coefficient after chilling was not only related to pitting and decay, but also to between pitting and decay was low and not significant (r = 0.44).
the resistance of the fruit to chilling and the incidence of brown Decay ratings for Dorado, Advantage and Rio Grande varied discolouration. Patches of brown stains randomly located on pitted between 2.4 to 2.6 after 21 days at 7oC plus 3 days at 20oC with and non-pitted areas against the red fruit skin background were fruits showing relatively high resistance to chilling injury (CI) and observed for those cultivars with moderate to severe chilling injury.
values ranging from 8.8-9.0 (Table 1). Similar findings were The decline in chilling sensitivity of some of the tomato cultivars obtained for non-processing cultivars Star Pak and Walters with highlighted above might be due to changes in endogenous C H decay ratings of 3.6 and chilling injury resistance scores of 9.0 - levels. In other studies, Kader and Morris (1975) found that C H 9.1 (Table 1). Cultivars with the least resistance to chilling injury treatment of mature-green and breaker tomatoes did not affect were Caraibe, Cascade, Early Set, Carnival and Capitan (Table 1).
chilling sensitivity. Perhaps other hormones or the interaction of 2 Meanwhile, control fruit stored continuously at 20oC showed no or more hormones may be involved according to arguments by pitting nor chilling injury symptoms as expected, but nevertheless, Autio and Bramlage (1986). On the other hand this decline in had an abbreviated shelf life of 8-11 days depending on cultivar, chilling sensitivity may be related to one of the many physiological and biochemical changes that may occur during the initiation of The high resistance to chilling injury for processing and non- tomato ripening. Since the fruits were ripened off the plant in this processing cultivars mentioned above is consistent with high quality investigation, the decline might have been related to temperature ratings from the time fruit were assessed after 21 days at 7oC (SR1) conditioning, as has been reported for grapefruit by Hatton and and then after 21 days at 7oC plus 3 days at 20oC (SR3) (Table 2).
Table 1. Severity of pitting, decay and resistance to chilling injury of table-ripe processing and non-processing tomato cultivars kept at 70C for
21 days (SRI) and upon transfer to 200C for 1 day (SR1) or 3 days (SR3), respectively
Cultivar
Pittingz
Decayz Resistance to
Processing
Dorado
Non-processing
Calypso
Z Pitting and decay were scored on a 8-point Hedonic scale (0 = no pitting or decay; 8 = severe pitting and decay).
Y Resistance to CI was scored on a scale of 1 = most susceptible and 10 = most resistant Table 2. Changes in overall quality and degree of brown discolouration of table-ripe processing and non-processing tomato cultivars
kept at 7°C for 21 days (SR1) and upon transfer to 20°C for 1 day (SR2) or 3 days (SR3), respectively
Cultivar Overall qualityz Decrease in
Degree of brown discolourationY
Quality (%)
Processing
Dorado
Non-processing
Calypso
Z Overall quality was scored on an 8-point Hedonic scale (0 = poor; 8 = excellent quality). Y Degree of brown discolouration, was measuredsubjectively on a 5-point Hedonic scale (0 = no brown discolouration; 5 = above 75% brown discolouration) Fruit from the various processing and non-processing tomato Hatton, T.T. and R.H. Cubbedge, 1982. Conditioning Florida grapefruit cultivars exhibited differences in sensitivity to chilling injury as to reduce chilling injury during low temperature storage. J. Amer. shown in Tables 1 and 2. The variability in correlations among the measurement of chilling sensitivity within and among these Hobson, G.E. 1981. The short-term storage of tomato fruit. J. Hortic. tomato cultivars indicated that their physiological andhorticultural response to chilling is complex. This is in Kader, A.A. and L.L. Morris, 1975. Amelioration of chilling injury symptoms on tomato fruits. HortScience, 10: 324 (Abstr.) agreement with Cabrera and Saltveit’s (1992) argument in earlier King, M.M. and P.M. Ludford, 1983. Chilling injury and electrolyte studies which postulated that breeding to reduce chilling injury leakage in fruit of different tomato cultivar. J. Amer. Soc. Hort. Sci., would necessitate the adoption of several approaches to encompass the diversity of the responses mentioned.
Lipton, W.J. 1978. Chilling injury of ‘Honey Dew’ muskmelons.
Symptoms and relation to degree of ripeness at harvest. HortScience, Acknowledgment
McColloch, L.P. and J.T. Worthington, 1952. Low temperature as a factor The authors wish to thank Mr. Sarran Harryram and Ms. Andrea in the susceptibility of mature-green tomatoes to Alternaria rot.
Houston for their help in field work and typing of the manuscript, respectively. Many thanks to Caribbean Chemicals Company Mohammed, M. and J.K. Brecht, 1999. Influence of ethylene treatments Limited and Wyatt Company Limited for supplying seeds.
on the alleviation of chilling injury in mango (cv. Palmer). Acta Hortic.,509(1): 437-446.
References
Mukerjee, R.K. and R.B. Srivastava, 1979. Increasing the storage life of mangoes (Mangifera indica, L.) by lowering the critical temperature.
Abou-Aziz, A.B., S.M. El-Nataway, F.K. Adel-Wahab and A.A. Kader, 1976. The effect of storage temperature on quality and decay Nazeeb, M. and W.J. Broughton, 1978. Storage conditions and ripening percentage of ‘Pairi’ and ‘Taimour’ mango fruit. Sci. Hortic., 5: 65- of papaya ‘Bentong and Taiping’. Sci. Hortic., 9: 265-277.
Saltveit, M.E., Jr. and L.L. Morris, 1990. Overview of chilling injury of Autio, W.R. and W.J. Bramlage, 1986. Chilling sensitivity of tomato horticultural crops, p. 1-14. In: C.Y. Wang (ed.) Chilling injury of fruits in relation to ripening and senescence. J. Amer. Soc. Hort. Sci., horticultural crops. CRC Press, Boca Raton, Fla.
Thorne, S.N. and S. Alvarez, 1982. The effect of irregular storage Buescher, R.W. 1974. Quality changes in tomatoes as affected by low temperatures on firmness and surface colour in tomatoes. J. Sci. Food temperature storage of unripe fruit. Arkansas Farm Res., 23: 11-12.
Cabrera, R.M. and M.E. Saltveit Jr., 1992. Cucumber cultivars differ in United Fresh Fruit and Vegetable Assn. 1975. Colour classification their response to chilling temperatures. J. Amer. Soc. Hort. Sci., requirements in tomatoes. USDA Visual Aid TM-L-1. The John Couey, H.M. 1982. Chilling injury of crops of tropical and sub-tropical origin. HortScience, 17: 162-165.

Source: http://www.horticultureresearch.net/journal_pdf/200076-78.pdf