ORIGINAL SCIENTIFIC PAPER Genotype influence on sensory quality of roast sweet pepper (Capsicum annuum L.) Galina Pevicharova, Velichka Todorova Maritsa Vegetable Crops Research institute, Brezovsko shosse street 32, Plovdiv, Bulgaria (gpevicharova@abv.bg) Abstract Sweet pepper cultivars from Serbia, Turkey and Bulgaria were estimated at three harvest times for their sensory profile as roast pepper. The aim was to search for appropriate parental components for breeding of new varieties and hybrids suitable for roast pepper production. It was established much higher influence of genotype (52.20 %) on the sensory evaluations than the harvest time (4.13 %). The total sensory evaluation correlated strongly with the overall taste and moderately with two of the components of the taste: sweetness and texture. The breeder s attention should be paid on them as the important traits in quality breeding for developing of pepper cultivars suitable for roasting. Key words: cultivars, harvest time, panel test, correlation Introduction Sweet pepper is a highly valued crop in the world. It is known for its plant nutrients that have disease preventing and health promoting properties (Marín et al., 2004; Deepaa et al., 2006). Among the forth maturity stages (immature green, green, immature red, and red) the red one possesses enhanced functional properties (Deepaa et al., 2007). Apart from its biological value sweet pepper has a very good taste. Red pepper of kapia type is a traditional vegetable crop in Bulgaria. It is a preferred raw material for producing sterilized pepper, pepper concentrates and roast pepper. Developing of new cultivars suitable for processing of roast pepper is an important part of the breeding program at Maritsa Institute (Todorova, 2006; Pevicharova et al., 2006; Todorva et al., 2007). The breeding process meets the specific requirements for this production. The fruits should be in intensive and homogeneous red colour, thick enough, easily peeled, sweet and not bitter. The aim of this study was to evaluate the sensory characteristics of pepper cultivars from the Balkan region in order to search for appropriate parental components for breeding of new varieties and hybrids suitable for roast pepper production. Material and methods The study was conducted at Maritsa Vegetable Crops Research Institute during the period 2005 2006. Three sweet pepper cultivars from Serbia ( Amfora, Palanačko čudo and Slonovo uvo ), one from Turkey ( Igglik irri ) and three from Bulgaria ( Kurtovska kapia 1619, Sofiiska kapia, Kapia UV and perspective line L 1045/05) were estimated. The sowing was done at the end of March in a non heated glasshouse. In the middle of May the seedlings were transplanted in alluvial-meadow soil. The experiment was carried out under open field conditions by randomized block design in four replications with 50 plants per each replication on furrow surface by 70/15 cm scheme. The plants were grown according to the adopted technology for mid-early open field production. The fruits for sensory analysis were picked at three harvest times every 15 days during the mass fruiting period. Ten fruits from each cultivar per replication were roasted on a grill and then peeled. The sensory analysis was performed on the traits pericarp colour, aroma, 49. hrvatski i 9. međunarodni simpozij agronoma Dubrovnik Hrvatska 259
Genetics, Plant Breeding and Seed Production sweetness, bitterness, hotness, texture and overall taste. A hedonic scale with a five-point panel with 0.25-step was used. The total sensory evaluation was formed on the basis of complete perception, but not as an arithmetic average from evaluation for individual sensory traits. The same four certified panelists participated in the course during the two experimental years. The results were processed by Duncan s multiple range tests, correlation analysis and two-way analysis of variance (SPSS software). Results and discussion Pepper cultivars differed in all investigated sensory traits during the three harvest times (Table 1). In the first one the highest total sensory evaluation was given to Sofiiska kapia because of the saturated red colour, typical aroma, good sweetness and a very nice texture. Table 1. Sensory analysis of roast sweet pepper cultivars Cultivars Sensory traits Per ica rp Ar om a Sw eet nes Bit ter nes Ho tne ss Te xtu re Ov era ll To tal sen I harvest time Kurtovska kapia 1619 4.5 ab 4.4 a 4.3 ab 4.4 a 4.7 a 4.4 b 4.3 ab 4.4 b Sofiiska kapia 4.6 a 4.6 a 4.2 ab 4.2 ab 4.6 ab 4.7 a 4.4 a 4.6 a Kapia UV 4.1 d 4.2 ab 4.3 ab 4.3 ab 4.6 ab 4.1 c 4.0 c 4.3 bc L 1045/05 4.3 c 4.1 b 3.8 c 4.3 ab 4.6 ab 4.4 b 4.0 b 4.0 c Amfora 4.4 c 4.4 a 4.3 ab 4.4 a 4.5 b 4.5 ab 4.3 ab 4.4 b Palanačko čudo 4.4 c 4.3 a 4.3 ab 4.1 bc 4.5 b 4.6 a 4.4 a 4.4 b Slonovo uvo 4.4 c 4.3 a 4.1 b 4.0 c 4.3 c 4.5 ab 4.2 ab 4.2 c Iglik irri 4.4 c 4.3 a 4.4 a 4.3 ab 4.5 b 4.6 a 4.4 a 4.3 bc II harvest time Kurtovska kapia 1619 4.5 bc 4.5 a 4.4 bc 4.6 a 4.8 a 4.4 b 4.3 abc 4.5 a Sofiiska kapia 4.6 ab 4.3 b 4.3 bcd 4.5 ab 4.7 ab 4.4 b 4.4 a 4.5 a Kapia UV 4.3 cd 4.1 c 3.9 e 4.3 c 4.5 d 4.1 c 4.0 d 4.0 c L 1045/05 4.5 bc 4.3 b 4.0 d 4.5 ab 4.7 ab 4.4 b 4.2 c 4.1 c Amfora 4.4 bcd 4.2 bc 4.3 bcd 4.3 c 4.6 cd 4.5 ab 4.3 abc 4.4 a Palanačko čudo 4.2 d 4.5 a 4.5 a 4.4 b 4.6 cd 4.6 a 4.4 a 4.4 a Slonovo uvo 4.2 d 4.2 bc 4.3 bcd 4.4 b 4.6 cd 4.5 ab 4.2 bc 4.3 b Iglik irri 4.7 a 4.5 a 4.4 bc 4.5 ab 4.8 a 4.6 a 4.4 a 4.5 a III harvest time Kurtovska kapia 1619 4.5 a 4.3 b 4.1 d 4.4 ab 4.8 ab 4.6 ab 4.2 bcd 4.2 c Sofiiska kapia 4.3 bc 4.5 a 4.6 a 4.6 a 4.9 a 4.5 b 4.6 a 4.5 a Kapia UV 4.4 ab 4.5 a 4.2 bcd 4.1 c 4.6 cd 4.3 c 4.0 d 4.1 d L 1045/05 4.2 c 4.3 b 4.1 d 4.3 bc 4.5 d 4.6 ab 4.3 bc 4.2 d Amfora 4.3 bc 4.3 b 4.3 bc 4.3 bc 4.8 ab 4.6 ab 4.4 b 4.4 ab Palanačko čudo 4.3 bc 4.2 b 4.1 d 4.2 bc 4.6 cd 4.7 a 4.3 bc 4.3 bc Slonovo uvo 4.2 c 4.3 b 4.4 b 4.3 bc 4.7 bc 4.7 a 4.1 cd 4.2 c Iglik irri 4.4 ab 4.3 b 4.2 bcd 4.1 d 4.7 bc 4.3 c 4.3 bc 4.3 bc a,b.. Duncan s multiple range test (p<0.05) Significantly lower evaluations were obtained for L 1045/05 and Slonovo uvo probably due to а smaller amounts of sugars in the fruits. Varieties Kurtovska kapia 1619 and Iglik irri were the leaders in the second harvest time. The panelists liked Kapia UV and L 1045/05 least for the reason mentioned above. In the third harvest time Sofiiska kapia was given the highest sensory evaluation while Kapia UV obtained the lowest one. 260 49 th Croatian & 9 th International Symposium on Agriculture Dubrovnik Croatia
The results presented here show that the genotype influences on the sensory quality of roast pepper. There were cultivars with constant expression of this feature. Sofiiska kapia was distinguished by the highest total sensory evaluation regardless of the harvest time. There was a tendency Kapia UV and L 1045/05 to be less acceptable for roast pepper production among the studied cultivars. The other cultivars showed variable behavior toward their sensory profile. As a whole, all studied cultivars had good sensory characteristic. The data from two-way analysis of variance showed significant influence over 30 % of the genotype on the sensory evaluations for pericarp colour, sweetness, texture and overall taste (Figure 1). The power of harvest time was high only for bitterness and hotness. 32.58 % 32.46 %** 58.02 %** 28.34 % 25.28 % 32.20 %** 30.60 %** 4.36 %* 4.06 % 9.59 % 39.18 %* 3.34 % Pericarp colour Aroma Sweetness 31.44 % 22.94 %* 21.41 % 20.55 %* 16.47 % 61.29 %*** 24.70 % 20.92%** 33.01* % 25.02 %*** 17.95 % 4.28 % Bitterness Hotness Texture 26.10 % 60.85 %*** 15.22 % 52.20 %*** 12.90 % 0.15 % 22.74 %* 4.13 % Overall taste Total sensory evaluation Graph 1. Two-way analysis of variance (factor A genotype, factor B harvest time) Having in mind comparatively high evaluations given for the two traits, we could accept that this influence is not important for the breeding process. The interaction between factor A (genotype) and factor B (harvest time) was significant for pericarp colour and sweetness. The effect of genotype factor on the total sensory evaluation was stronger than the harvest time during the experimental period. The power of harvest time as a single factor on the total sensory characteristic was not significant. The varieties expressed at some degree the differences in their sensory properties in separate harvest time which has reflected in the value of interaction A B. This means that only one harvest is not sufficient in order that 49. hrvatski i 9. međunarodni simpozij agronoma Dubrovnik Hrvatska 261
Genetics, Plant Breeding and Seed Production precise sensory evaluation of roast pepper properties to be obtained. Similar results were observed in salad and pickling cucumbers (Pevicharova and Velkov, 2007; 2009). The total sensory evaluation correlated strongly with the overall taste and moderately with two of the components of the taste - sweetness and texture (Table 2). The breeder s attention should be paid on them as the important traits in quality breeding for developing of pepper varieties and hybrids suitable for roasting. Table 2. Correlations between the total sensory evaluation and the studied sensory traits Pericarp colour Aroma Sweetness Bitterness Hotness Texture Overall taste Total sensory evaluation Fist experimental year (n = 96) Pericarp 0.308** 0.138 0.062 0.049 0.163* 0.187** 0.189** colour Aroma -0.001 0.401** 0.099 0.068 0.355** 0.347** 0.336** Sweetness 0.014 0.551** 0.245** 0.140 0.362** 0.621** 0.580** Bitterness 0.078 0.348* 0.363* 0.522** 0.442** 0.361** 0.428** Hotness 0.200 0.214 0.182 0.635** 0.278** 0.320** 0.350** Texture -0.094 0.271 0.267 0.472** 0.238 0.468** 0.545** Overall taste -0.033 0.514** 0.695** 0.671** 0.356* 0.579** 0.818** Total sensory 0.111 0.455** 0.683** 0.636** 0.369** 0.604** 0.878** evaluation Second experimental year (n = 96) Conclusions Genotype factor influences at high degree on the sensory profile of roast pepper of kapia type. From organoleptic point of view cultivar Sofiiska kapia is the most appropriate parental component among the studied sweet pepper cultivars. It keeps high total sensory evaluation regardless of the harvest time. For breeding purposes aimed to creation of new varieties and hybrids suitable for roast pepper production sensory analysis should be performed at least two harvests of the pepper fruits. More precise information will be obtained by estimation of number of samples collected at different harvest times. The overall taste, sweetness and texture effect on the formation of the total sensory evaluation. They should be taken into account during the process of high quality sweet pepper breeding. References Deepaa N., Kaura Ch., Singhb B., and Kapoor H. (2006). Antioxidant activity in some red sweet pepper cultivars. Journal of Food Composition and Analysis 19 (6 7): 572 578. Deepaa N., Kaura Ch., Georgea B., Singhb B., and Kapoor H. (2007). Antioxidant constituents in some sweet pepper (Capsicum annuum L.) genotypes during maturity. LWT - Food Science and Technology 40 (1): 121 129. Marín A., Ferreres F., Tomás-Barberán F., and Gil M. (2004). Characterization and quantitation of antioxidant constituents of sweet pepper (Capsicum annuum L.). Journal of Agricultural and Food Chemistry 52 (12): 3861 3869. 262 49 th Croatian & 9 th International Symposium on Agriculture Dubrovnik Croatia
Pevicharova G., Todorova V., and Todorov J. (2007). Ascorbic acid and total sugars content of kapiya type pepper depending on cultivars and climatic conditions. Plant science 44 (1): 52 56, (Bg). Pevicharova G. and Velkov N. (2007). Sensory analysis of cucumber varieties at different harvest times I. Salad cucumbers. Journal of Central European Agriculture 1: 25-31. Pevicharova G. and Velkov N. (2009). Sensory analysis of cucumber varieties at different harvest times II. Pickling cucumbers. Journal of Central European Agriculture 10 (3): 289-295. Todorova V. (2006). Influence of the variation factors on the expression of some morphological plant characters in pepper kapiya type varieties and breeding lines (Capsicum annuum L.). Ecology and Future 5 (4): 18 20. Todorova V. (2007). Fruit Characterization and influence of variation factors in pepper kapiya type varieties and breeding lines (Capsicum annuum L.). Bulgarian Journal of Agricultural Science 13 (3) 309-315. Todorova V., Todorov Y., Ivanova I. (2007). Study on pepper cultivars and breeding lines kapiya type by yield. Plant science 44: 44 47, (Bg). 49. hrvatski i 9. međunarodni simpozij agronoma Dubrovnik Hrvatska 263