The mamey (Pouteria sapota (Jacq) H. E. Moore & Stearn) is a native fruit of Central America. In Mexico it develops in tropical and subtropical regions, and is considered an underutilized species (^{Mooseler and Nesheim, 2002}). In Mexico (^{SIACON, 2007}) the production of this fruit is estimated at 14 024 t in 1 330 ha. The main producing states were Chiapas, Guerrero, Tabasco and Yucatan. In the country mamey production it is mainly based on segregating materials, resulting in variability in the amount and quality of fruit; however, there are varieties (Danny Magana I, II and III), characterized by their fruits average weight of 800 g limiting fresh consumption (^{Campbell, 1992}). The fruits of increased demand as fresh fruit are characterized by weight of 300-500 g, red pulp and low fiber content and produce some native materials. The variability found in the state of Guerrero materials have been selected considering morphological characteristics of the plant, fruiting pattern, quantity, quality and harvest time of production (^{Bayuelo and Ochoa, 2006}). In the state of Guerrero are featured native materials, the fruits of 11 of these anatomical, physico-chemical and physiological characteristics related to quality and postharvest life of fruit are considering.

The trees characterized developed in the municipality of Alpoyeca located in Glen Huamuxtitlán, Guerrero, Mexico (17° 41 'north latitude and 98° 30' west longitude and an altitude of 1 030 m). The 11 genotypes appointed by producers and characterized by their production, fruit size, color pulp and many seeds were selected. The fruits are harvested when the pulp under the shell had a characteristic pink-crimson, then cut with a basket of conventional use for crop of fruit. They were transported in plastic boxes postharvest laboratory of the graduate school for analysis. The 70 fruits per tree, 20 were used to make constant (and 50 measurements for destructive analysis during the experiment, all stored at room temperature (20±3 °C and 50-60% relative humidity). For seven days were measured: weight (g), length (cm), diameter (cm), index (length/ diameter) ratio and seed/pulp/peel (weighing each of the components).

During storage were sampled randomly, every other day 10 fruits for measure: color pulp with a colorimeter (Hunter Lab D25-PC2 scale CIE L*a*b) to calculate the angle of the hue (°Hue= arc tan b/a) and the saturation index (Chroma= ( a² + b² )^1/2) according to ^{McGuire (1992)} and the color index (IC= ab/L) proposed by ^{Villanueva-Arce et al. (2000)}. The pulp firmness was measured with a texture analyzer (FDV- 30; 30 lb X 0.01 lb) using a conical strut 8 mm in diameter and reporting the penetration resistance in Newtons. Total sugars pulp quantitated by anthrone method (^{Witham et al., 1971}) and reporting the data as mg 100 g^-1.

Also in 10 fruits measures weight losses were made, for which daily, from harvest to consumption maturity, the weight of each fruit and differences from baseline was determined percentage was obtained cumulative losses. For data analysis statistical design was used completely randomized experimental unit being a fruit and with 10 repetitions per day evaluation. The data analysis was performed using the Statistical Analysis System (^{SAS, 1999}) using the technique of analysis of variance and comparison of means by Tukey (p≤ 0.05) statistical package. Regarding the morphological characteristics of the fruit, statistically significant differences (p≤ 0.05) in the average weight of the fruits they were presented.

The greatest weight Pardo III and Juanito had 824 and 0.671 g, respectively. The lower weight accounted Gift and Pardo II with 367 g and 369 g, respectively. Other materials showed a weight between 427 (Cid) and 551 g (Pardo I) (Table 1). The proportion of pulp (> 80%) was observed in the Cid, Genaro, Pardo III, Gift and Risueño selections; the highest proportion of shell (>11%) corresponded to the Cid, Dario Diaz, Juanito, I Pardo, Pardo II, III Pardo and Red selections. The lower proportion of seed (<8%) occurred in the Cid, Pardo III and Risueño selections.

According to ^{Alia et al. (2002)} the size of the fruits of mamey in Morelos, Mexico varies between 200 g-3 kg. The larger materials are intended for processing pulp and smaller fresh consumption. In general consumers prefer fruits of 350 to 500 g. This establishes that Cid, Dario Diaz, Genaro, Pardo I, Risueño and Red have the desirable size. In the same vein, Risueño excels with an acceptable weight of 493 g, as much pulp (83.8%) and the lowest proportion of seed (7.8%) and Shell (8.3%); Red instead had a weight of 451 g and a proportion of 77.6, 10.2 and 12.2% pulp, seed and shell, respectively. ^{Sandoval et al. (2006)} reported that at physiological maturity had 80% fruit pulp and peel while seed accounted for 18 and 2%, respectively. This is similar to what was found in this study, highlighting Risueño, Genaro, Gift and Brown III for its high content of pulp.

The fruits of Dario, Genaro, and Pardo Juanito selections have an elongated shape (IF>2.0), while Pardo II, III Pardo, Risueño and Red are more rounded shape (IF<1.5). The elongated presented according to ^{Espinosa et al. (2005)}, sensitivity to mechanical damage, since the firmness decreases the apex to the base, which raises the need to handle it with utmost care.

Regarding the characteristics of fruit ripening, color there were no statistically significant differences in L, hue angle and saturation index, not in the color index (IC= ab/L), ^{Villanueva-Arce et al. (2000)} indicate that close to 12 values correspond to red hues; In this sense, the first day after harvest the color of orange pulp accounted colors (color charts RHS) while the Color Index had values close to 10. On the first day allowing assume that the harvest the fruits of Diaz Pardo II, III and gift selections Pardo showed statistically greater color intensity (Table 3). During ripening the fruits changed its color to orange-red shades (color charts RHS), except Risueño and orange-red with intense hue.

After 5 d of storage no statistical differences in color between materials were presented. According to ^{Alia et al. (2007)} the bright orange-red pulp mamey fruits is due to the presence of carotenoids, mainly β-carotene. In addition, ^{Ramos-Ramirez et al. (2009)} indicate that the opacity of the color is related to the presence of total phenols and weight loss. Regarding the opacity ^{Alia et al. (2005b)} report that some of the compounds cinnamic acid derivatives can be substrate for the darkening of the pulp.

The first day after harvest the pulp firmness showed no statistically significant differences between the 11 selections, establishing these in an average of 37.9 N; about ^{Alia-Tejacal et al. (2007)} found that the firmness of mamey fruits at physiological maturity is between 35 and 65 N. Also, after 3 d of exposure to ripening conditions showed no statistical difference in the firmness of the pulp of the 11 selections, if while the overall average of this decreased to 33.76 N. significant differences were presented on the fifth day of maturation, also corresponding to the time when the fruits reached maturity consumption, since the seventh day all selections had problems fermentation; In this sense, the fruits of the Cid (33.3 N), Genaro (41.3 N) and Pardo II (29.2 N) teams reached the maturity of consumption higher pulp firmness, respect Dario (15.6 N), Juanito (21.7), Pardo I (23.4 N) and Brown III (20.3 N); is less firmly Diaz, Gift, Risueño and Red with 2.8, 2.3, 9.9 and 1.4 N, respectively.

^{Alia-Tejacal et al. (2007)} report values of firmness in fruit pulp native mamey at maturity of 3-12 N consumption, while ^{Diaz-Perez et al. (2000)} report values 20 to 50 N.

Furthermore, ^{Tellez et al. (2009)} reported that during the ripening period, the fruit firmness decreased from 40.6 to 0.83 N, the above highlights the great diversity in fruit softening due to different genetic origin; is noted that in this paper no preference tests were performed to determine the best pulp firmness that relates to the optimal maturity of consumption.

During maturation showed statistically significant difference in the content of total sugars in all periods evaluated. The first day after harvesting Diaz, Juanito and Red teams had the highest concentrations with 31.0, 31.6 and 28.6%, respectively, lower in Cid, Genaro, Pardo I, Pardo III and Risueño, with concentrations of 4.3, 6.2, 5.3, 7.0, and 3.9% in the same order; the rest of the selections had an average content of 16.1% (Table 4); ^{Alia-Tejacal et al. (2005a)} have reported content of 2.7-8.2% at harvest in native fruit mamey developed in Coatlán del Río, Morelos, which shows differences in the quality of mamey fruits due to the origin of the genetic material. As the Diaz evolved maturation selections and Juanito its sugar content decreased to 19.4 and 25.9% the third and fifth day, respectively; both cultivars had the highest rate of color that allows for a diversion synthesis of sugars to pigment related color pulp, ^{Alia-Tejacal et al. (2007)} reported significant increases in the carotenoid content during ripening fruit mamey.

Another group of teams like Red (42.8%), Dario (19.6%) and Pardo II (23.7%) reaches its highest sugar content on the third day after harvest to subsequently decrease to 5 and 7 d of ripening; meanwhile the Genaro and Brown III teams reach their highest concentration of sugars within five days after harvest with 19.6 and 30.4% respectively, while 'Cid' (12.4%), Pardo I (10.9%) and Risueño (11.4 %) on the seventh day (Table 4). These results are indicative of the different biochemical and physiological behaviors between fruits from plants with genetic variability, a situation which in turn reveals differences in quality.

As for the cumulative weight loss, the fifth day of storage differences were significant statistical, being Rojo less prone to water loss through transpiration with 5.5% loss of weight selection, while Dario (9.7%) and Juanito (9.3%) susceptible to such losses. It should be noted, that the fruits with greater weight loss pulp presented ridging near the seed affecting the appearance of it. The values found are similar to those reported by ^{Saucedo-Veloz et al. (2001)}, ^{Alia et al. (2005a)} and ^{Ramos-Ramirez et al. (2009)} who reported weight loss between 1.0 and 1.9% daily.