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- Author or Editor: Juan L. Silva x
- HortScience x
A total of 6 cvs and 14 lines of sweetpotatoes were analyzed by sensory panel for baking and canning quality. Baked samples were cured, washed, foil-wrapped, and baked for 1.5 h at 177°C. Canned samples were lye peeled and finished, packed with 20°Brix sucrose in 303 × 406 cans, and retorted for 25 min at 121.1°C. Beauregard and 'L86-33' scored the highest on canned samples. In analyzing the different sensory attributes, color uniformity had the highest partial R2 for both baked (0.61) and canned (0.67) products. Moistness (R2=0.13) and mouthfeel (R2=0.15) were the subsequent important factors followed by eye appeal, smoothness, lack of fiber and attractiveness. Thus color attributes accounted for 67.0% (baked) and 78.4% (canned) of the average rating of sweetpotatoes. Textural attributes followed with flavor being last with 1.0% and 1.1%. for baked and canned products, respectively. When averaging all samples, eye appeal and color uniformity were below the acceptable rating (6) in baked samples. For canned samples. attractiveness and color intensity were rated the lowest. This work shows that the average or total score given to a cv/line should be the result of the weighted scores of each attribute rated and not the arithmetic mean. Also, breeders should incorporate color intensity, uniformity, and susceptibility to browning ratings early in their program.
Models for prediction of starch, alcohol-insoluble solids (AIS) and glucose were developed by measuring the viscosity of freeze-dried sweetpotato [Ipomoea batatas (L.) Lam] flour. Green (processed within 24 h) and cured. Jewel and Beauregard roots-were cooked, peeled, pureed and freeze-dried. Viscosity of the flour was measured with a Brabender Viscoamylograph and a Brookfield Viscosimeter. Total solids, starch, AIS, glucose, fructose and sucrose were quantified. There was a strong correlation (R2=0.99) between Brookfield and Brabender viscosity. Results showed significant correlations between Brookfield apparent viscosity or Brabender viscosity units at the gelatinization stage and starch (R2=0.82 and 0.81), AIS (R2=0.S7 and 0.81), and glucose (R2=0.87 and 0.86) content. Apparent viscosity of flour from green roots increased through gelatinization and upon cooling, but that from cured roots remained constant throughout.
Characteristics of mangosteen fruit with normal and translucent flesh were determined. Fruit exhibiting translucent flesh disorder had significantly higher rind (65%) and flesh (82%) water content than fruit with normal flesh (63% and 80% in the rind and flesh, respectively). Specific gravity of translucent flesh fruit was >1 and that of normal flesh fruit was <1. Fruit specific gravity and natural transverse rind cracking were used to separate translucent-fleshed fruit from normal fruit. Translucent-fleshed fruit had a lower soluble solids concentration and titratable acid percentage than normal fruit. Translucent flesh was induced in normal fruit following water infiltration at 39 kPa for 5 minutes.
Fresh shelled southern peas were dipped in solutions of 15 ppm chlorine, 1.0% Ca, cold H2O or a combination of 15 ppm chlorine and 1.0% Ca. These treatments were compared to a no dip treatment and branching for 70 sec. at 205°F. Polyphenoloxidase (PPO) activity of pea extracts were determined in 5 day intervals for 20 days. Quality evaluations for color changes and texture were also made. PPO activity was the only enzyme that showed an increase in activity with refrigeration time. The blanched peas were lower in quality for a fresh refrigerated product.
Sixteen sweet potato (Ipomoea batatas L.) genotypes were chilled for 36 hours at 5C with 85% RH and a 12 hour photoperiod. Transpiration, leaf diffusive resistance and visual scores for plant quality were taken before chilling and 2 days after the chilling treatment. Differences between the before and after readings were used to indicate the extent of chilling injury or tolerance. Visual score gave a better separation of the genotype for tolerance, however, the difference in transpiration was the most critical of the two objective measurements.
The volatiles of longon (Lansium domesticum Corr. var Dongon), mangosteen (Garcinia mangostana L. var Native), durian (Durio zibethinus L. var Monthong), rambutan (Nephelium lappaceum L. var Rong-rien), and sapodilla (Manilkara zapota van Royer var Kai) were identified by headspace-solid phase microextraction with the gas chromatography-mass spectrometry technique. The headspace volatiles of fresh, unheated, salted out with NaCl, and NaCl + heated samples were determined. Salting out gave the highest number of volatile components with the longon headspace. High temperature did not have much affect on the amount of volatiles in the headspace. Major volatiles of the total 43 volatiles in longon were 1,3,5 trioxane, (E)-2-hexenal, 3-carene, α-cubebene, isoledene, δ-selinene, and α-calacorene. Major volatiles of mangosteen were 2, 2-dimethyl-4-octanal, E-2-hexenal, benzaldehyde, (Z)-3-hexen-1-ol, hexyl–n-valerate, 1,4-pentadiene, and 2-methyl-1, 3-buten-2-ol. Volatile compounds in durian consisted of a large number of sulfur-containing compounds, which included diethyltrisulfide, diethyldisulfide, dithiolane, dimetyl sulfide, and 3-methyl-thiozolidine. Nonsulfur compounds 2-methyl butanoate, butanedioic acid, and propyl-2-ethylbutanoate were also abundant. Isocitonellol, 3-hydroxy-2-butanone, pentanal, and 4-tridecyl valerate were most abundant in ‘Rong-rien’ rambutan. A total of 23 components were characterized in sapodilla with ethyl acetate, acetaldehyde, benzyl alcohol, and 2-butenyl benzene being the major volatiles.