Variability of physio-chemical, anti-oxidant, and sensorial quality of newly released papaya varieties in Ethiopia

Papaya (Carica papaya L.) is one of the important and versatile fruits and grown worldwide in the tropics and subtropics including India, Bangladesh, Malaysia, Australia, Hawaii, Philippines, Sri Lanka, South Africa, and other countries in tropical America [1]. Papaya has been ranked as one of the tops for nutritional value among 38 common fruits [2]. It is available all around the year and consumed as fruit after ripe and green papaya as a vegetable. Besides, they have medicinal properties and have been used against diseases for many years [3,4]. Practically every part of the fruit is used for a variety of medical purposes [5]. It has been argued by scientists that all parts of papaya, including seeds, roots, rinds, and fruits have positive effects on general health preventing diseases [6].


Introduction
Papaya (Carica papaya L.) is one of the important and versatile fruits and grown worldwide in the tropics and subtropics including India, Bangladesh, Malaysia, Australia, Hawaii, Philippines, Sri Lanka, South Africa, and other countries in tropical America [1]. Papaya has been ranked as one of the tops for nutritional value among 38 common fruits [2]. It is available all around the year and consumed as fruit after ripe and green papaya as a vegetable. Besides, they have medicinal properties and have been used against diseases for many years [3,4]. Practically every part of the fruit is used for a variety of medical purposes [5]. It has been argued by scientists that all parts of papaya, including seeds, roots, rinds, and fruits have positive effects on general health preventing diseases [6].
Fruit quality is one of the most important themes of the fruit industry, especially for juice and pulp processing as they have a direct impact on the use of additive synthetic products. Quality is defi ned as the absence of defects or degrees of excellence which consists of appearance, color, shape, injuries, fl avor, taste, aroma, nutritional value, and is safe for the consumer.
Physical and chemical properties of fruits are important indicators of their maturation and also the internal and external quality that affect market demands. Due to a higher market exigency for high-quality products, the juice, and pulp industries have been looking for fruits with better internal and external features, including fruit physical, chemical, and antioxidant contents [7]. Moreover; papaya also the main source of many vitamins, such as vitamin C, and it contains vitamin E, pectin, and carotenoids [8]. Despite its economic importance and nutritional value, papaya fruit had grown and produced on a large scale across the world including Ethiopia.
Citation: Minuye  attention and physic-chemical characteristics are important qualitative indexes of any fruit for fresh consumption [8].
Therefore; the present study aims was to conduct a detailed analysis and assess the variations in fruit physicochemical characteristics, nutritional and sensory evaluation of the three released papaya varieties in Ethiopia.

Sample collection and preparation
Papaya fruit samples were collected from eight randomly selected trees of each variety. The papaya samples were free from mechanical damage, insect infestation, disease, and physiological disorders. The three released papaya varieties (kk-103, MK-121, and CMF-078) were used for sample collection at a similar stage of maturity. The collected samples were stored at 12 o C for further analysis. Fruit maturity was defi ned based on the skin color change which is a yellow color that does cover more than 75% of the skin surface. Methods of Complete Random Design experimental design was used for this study Figure 1.

Sample preparation
Ripe fruit samples were washed with deionized water to remove dust particles and pathogens from the surface and quickly cleaned with a blotting paper. Fruit peels, pulp, and seed (kernel) were removed using a clean sharp knife and homogenized. The fl eshes of papaya fruits were dried with lyophilized for further analysis and some of the fresh fl esh was used to make juice to evaluate some physicochemical parameters, nutritional composition, and sensory analysis. All the parameters were analyzed using triplicate samples analysis.

Methods of analysis
Color of skin and fl esh: Skin and fl esh color of papaya fruit were determined through the standard method using a color chart.
Fruit weight: it was determined using a sensitive balance.
Fruit width, length, and diameter: Fruit width, length, and diameter were determined by using a digital caliper.
Juice P H : of the fruit was measured by taking a suffi cient quantity of papaya juice sample in 50 ml clean beaker and using P H meter (Type H1 98106 by HANNA).  fat, crude fi ber, and protein were determined following with [9] methods.

Carbohydrates (CHO)
It was determined by the difference (the measured protein, fat, ash, and moisture was subtracted from 100 [10], Gross food energy was estimated by the following equation; Where FE is the food energy, TC is the total carbohydrate content, CF is the crude fi ber, TF is the total fat and CP is the crude protein.

Carotenoids
Carotenoids were performed spectrophotometrically using the method described by [11]. Fresh papaya samples (5g) were ground with cold acetone with a mortar and pestle until the residue became colorless and then vacuum-fi ltered using a Buchner funnel. The extract was partitioned with petroleum ether, then each fraction was washed with distilled water for complete acetone removal. The extracts were made up to a volume of 50 mL with petroleum ether. All of the procedures were performed in dim light. The extracted carotenoids were collected and measured at 450 nm using a UV spectrophotometer.
Total carotenoids were calculated with the following equation: Where A is the absorbance, the volume is the total volume of extract (50), A1% 1cm is the absorption coeffi cient of -carotene in petroleum ether.

Sensory analysis
The sensory analysis was conducted by a semi-trained panelist of Melkassa agricultural research staff members following the standard procedures for a hedonic scale scoring of 1 to 5. (1-indicates dislike very much and 5-indicates like very much). Samples were evaluated for sweetness, color, fl avor, sourness, and overall acceptability by 15 semi-trained panelists.

Statistical analysis
Statistical analysis of the data was carried out using analysis of variance (ANOVA) technique for completely randomized design (CRD)and all pairwise comparisons test was carried out whereas, the Tukey HSD was used for comparison of the treatment means at P< 0.05

Results
Physical parameters of papaya fruit such as length, width, weight, and diameter were conducted as shown in Figure 2. Among the three-papaya fruit for all parameters of length, width, weight, and diameter, MK-121 variety was the highest on the other hand variety CMF-078 was the lowest for all physical parameters. Fruits of the three papaya varieties showed different physical characteristics such as length, weight, and diameter Knowing of fruit P H , Acidic value is a decisive thing to know fruit characteristics towards spoilage besides its nutritional aspect. In this study fruit PH, TSS, acidic value, skin, and fl esh color were included and the result showed that PH value was not signifi cantly different at p<0.05, and its value ranged from 5.284-5.667. KK-103 papaya variety had a higher TSS value than did the others. Titrable acidity of the three varieties was covered in the range of 1.455-1.979 as measured by gram/liter. Fruit fl esh and skin color were done using a color chart and as a result for variety MK-121 both fl esh and skin color (after ripping) was the same while the rest two varieties showed different in their skin and fl esh color Table 1. Anti-oxidants such as total carotenoids, beta-carotene, and

Discussion
For the three papaya fruits, physical parameters such as fruit length, weight, diameters, width, skin, and fl esh color  Table 1). The TSS values of papaya in the present study were similar to those which have been reported by [8,13]. Moreover, [8] also found that between 9.0 to 13.0% for the four varieties of papaya.
Among the common acids of fruit and vegetable, citric acid is the one which is the most abundant in papaya fruit and this research output also presented as a citric acid concentration.
In this fi nding fruit acidity (as citric acid) of the three papaya varieties was found to be between 1.454 (MK-121) to 1.978 g/l (CMF-078). Citric acid value for variety CMF-078 was higher than the two papaya varieties and had shown also signifi cant differences at P<0.05. The acidity value of the three-papaya fruits was in agreement with the fi ndings of [13,14]. Fruit with a lower PH and higher an acidity concentration has a better shelf-stable than the others, as a result, it is always chosen by the consumers. Research reports indicated that bioactive compounds, total soluble solids (TSS), and titratable acidity (TA) vary among different papaya cultivars [15,16] due to its differing of growing conditions as well its genotype.

Anti-oxidants
Papaya is a source of antioxidants such as vitamin A, E, B complex, vitamin C as compared to carrots and oranges [17] and also used as the cheapest source of carotenoids, [18]. In this research, the three anti-oxidant of papaya fruit such as vitamin C, total carotenoids, and beta-carotene were analyzed and presented in Figure 4. Varieties of papaya had shown a signifi cant difference for their Vitamin C content at P < 0.05 as shown in Figure 4. The highest vitamin C value was obtained from MK-121 variety (43.407) while the lowest value was found from CMF-078 (30.854). As reported by [8]

Sensory evaluation
Most of the studies on fresh-cut fruits have been concerned with the objective and subjective evaluation of market quality by color, sensory and texture measurements [26].
In the present study sensory evaluation of the three papaya varieties was performed subjectively and the analysis (color, fl avor, sourness, and sweetness) was done for complete ripe fruits. It was carried out by semi-trained panelists using fi ve hedonic scale methods and results presented in Figure 5. The results showed that color, fl avor, and sourness values were signifi cantly higher for variety MK-121 than the other two varieties meanwhile variety CMF-078 was higher for sweetness and overall acceptability. According to the panelist evaluation, as a general CMF-078 variety was higher followed by MK-121 for the overall acceptability.
As a general view from this fi nding, it is evident that the physic-chemical, anti-oxidant and sensorial parameters of vitamin A defi ciency in developing nations [21,22]   period [27][28][29]. This list of factors infl uences the nutrient contents of papaya varieties. Differences in the physicchemical composition of different papaya varieties are in agreement with the fi ndings of [27,30,31] research report.

Conclusion
Fruit physicochemical parameters of papaya varieties signifi cantly differed from each other, which could probably be due to different genetic make-up of the varieties, bringing about differences in the rate of fruit development. Nevertheless, the results of the present study indicated that fruits of variety CMF-078 exhibited higher overall acceptable value with higher customer preference. On the other hand, variety MK-121 had higher dry matter, protein, carbohydrate content, and energy value than did the other two varieties. It had also a better vitamin C, beta-carotene, and total carotenoids. Therefore, the researcher recommended that fruits of variety MK-121 could be used for fresh consumption as well as for processing purposes to produce vitamin A enriched foods.