Harvest Maturity and Fruit Quality Marita Cantwell Dept. Plant Sciences, UC Davis micantwell@ucdavis.edu Fruit Ripening and Ethylene Management Workshop UC Davis, April8-9, 9 California orange on plane returning from Indonesia PH workshop Nov 9, 7 Relationship between sugar/acid ratio and sensory panelist s Response to the question about Willingness to Buy navel oranges Number of responses Importance of Maturity Indices Sampling week Nov -8 Nov 8-Dec Dec - % samples below sugar/acid Ratio of 8.* 9 7 YES NO 8 7 7 Sensory and Nutritional Quality Use Fresh market or Processed Adequate shelf-life Facilitate marketing standards Productivity *from California A grade standard Source: Ivans and Feree, 987 Initiation Initiation Development Growth Death Death Maturation Physiological Maturity Developmental Continuum Ripening Senescence Evolution of some physical, chemical and physiological parameters during fruit development and ripening on the tree of Golden Globe Plum. Watada et al., 98 Diaz-Mula et al., 8. J. Sci. Food Agric 88:99-7
Development & Ripening of Honeydew Melons Harvested at Different Stages Maturity and Ripening Stages of Bartlett Pears Fruit weight, kg.... Soluble solids, % 8 Fruit weight Soluble solids Firmness Respiration Ethylene Data from Pratt, 977; redrawn from Seymour & McGlasson99 8 Firmness, kg cm Respiration, mg CO kg-h - Internal ethylene, µl L -. from anthesis Ripeness Class Terminology PHYSIOLOGICAL MATURITY The stage of development when a fruit will continue development even if detached; mature fruits HORTICULTURAL MATURITY The stage of development when a fruit possesses the necessary characteristics for use by consumers GROUP. Non-Climacteric Fruits Conditioning Color change may occur Softening may occur No increase in sugar Decrease in acidity Metabolic rate decreases Ethylene can be used to de-green GROUP. Climacteric Fruits Ripening Color change Softening often substantial Starch to sugar conversion Decrease in acidity Large increase in metabolism Ethylene used to trigger ripening Group * Non climacteric Fruits Fruits that are not capable of continuing ripening process (physiological changes) once removed from the plant. Blackberry Loquat Pomegranate Composition of Ripe Strawberry Harvested at different stages. Held at 7 F ( C) to complete color change. Cherry Grape Grapefruit Lemon Lime Litchi Mandarin Muskmelons Orange Pepper (Bell) Prickly Pear Rambutan Raspberry Strawberry Tamarillo Maturity % color % color 7% color % SS.8..98 % Acid.8.79.8 Ratio..77 7. Longan Pineapple Watermelon % color.8.9 9.8 *No increase in sugar content; Changes in firmness, external color, and aroma may occur
Maturity and Ripeness Stages of Cherries California strawberries and cherries at NTUC Distribution Center Singapore, May, 8 Strawberries from Oxnard; Cherries from Lodi Pineapple Stored at 7 C ( F) Maturity % Soluble solids days 7 Shipping green.9 8. 8. 8. ¼ color...7. ½ color...8.7 Full color.... Cantaloupe Maturity/Ripeness Fruit begins to separate from stem Abscission zone; slip External color between net Net well developed with wax Subtending leaf dries up Internal color, firmness, soluble solids The slip is is a very useful attribute & applicable to to old & new cantaloupe varieties Sugar loss in fresh-cut cantaloupe may be considerable, but Soluble solids do not change much; Sugar loss typically is not as extreme as in this example. mg/g fresh weight 9 8 7 Class (no slip) Class (/-/ slip) Fresh-cut Cantaloupe melon Changes in Sugar Content 8 at C ( F) Soluble Solids (%) 9 8 7 Soluble Solids (Average varieties) Stage (</ slip Stage (/ slip) Stage (full slip) 8 Sugar content (mg/ g fr.wt.) Sugars Typical loss over days at C ( F): S.S. -% Sugars -% 8
Honeydew and other melons Cut off the vine are more difficult to harvest at a specific Honeydew and Orange Flesh Melons Maturity and Ripeness Classes stage of ripeness Class : Immature Class : Mature, but Unripe Ground color greenish-white; peel fuzzy; no aroma; % soluble solids; flesh crisp, melon splits when cut; minimum commercial harvest maturity Class : Mature, Ripening Ground color white; begins to develop surface wax; pulp crisp, melon splits Minimum for Good Eating Group * Climacteric Fruits has significant amount of starch Fruits that can be harvested and ripened off the plant. Apple Mango Pepper (chili) Apricot Avocado Banana Cherimoya Guava Kiwifruit Mangosteen Nectarine Papaya Passion fruit Peach Pear Persimmon Plum Quince Sapodilla (chico) Sapotes Tomato Mr Tay, Hupco Ltd., Importer, Singapore, May8 *Except for avocado, banana, mango and pear, these fruits attain best flavor if ripened on the plant; Many of these fruits have large increases in sugar during ripening. ml O or CO per kg-h Ripening Fruits: Groups Climacteric Fruits 8 Breadfruit Cherimoya Mango 8 Fig Tomato Apple 8 ml O or CO per kg-h Nonclimacteric Fruits Strawberry Grape Pineapple Cherry Lemon 8 Indicators of Harvest Maturity APPLES from full bloom Time/temp (heat units) from anthesis from harvest to onset of ethylene production Ground color Soluble solids content (SSC) Flesh firmness and SSC Starch disappearance pattern Internal ethylene concentration Changes in firmness or starch content Streif index (Firmness/SS*Starch score)
Apple Maturity: starch index Apply the iodine solution** to the cut surface Drain away any excess, and rate the fruit after min. Starch-iodine reaction is temperature-dependent Starch pattern is variety specific. Golden Delicious at Retail Market: How is the maturity in this box? Rating system is a scale of to, as follows: = full starch (all blue-black) = clear of stain in seed cavity and halfway to vascular area = clear through the area including vascular bundles = half of flesh clear = starch just under skin = free of starch (no stain) ** Preparation of Iodine-Potassium Iodide (IKI) Solution for Starch Staining: Dissolve 8. g of potassium iodide (KI) in about ml of distilled water, then add. g iodine (I) and mix well until completely dissolved. Then complete the final volume to liters with distilled water. Store in a brown bottle or aluminum foil covered bottle. http://tfpg.cas.psu.edu/part/parta.htm; http://postharvest.ucdavis.edu Maturity and ripeness stages of Manila mango Mango Maturity Indices Fullness of shoulders External color dark to lighter green Internal color-white to yellow Lenticles and hairs on pit Starch content; specific gravity Group * Climacteric Fruits has significant amount of starch Fruits that can be harvested and ripened off the plant. Apple Mango Pepper (chili) Apricot Mangosteen Persimmon Avocado Nectarine Plum Banana Papaya Quince Cherimoya Passion fruit Sapodilla (chico) Guava Peach Sapotes Kiwifruit Pear Tomato *Except for avocado, banana, mango and pear, these fruits attain best flavor if ripened on the plant; Many of these fruits have large increases in sugar during ripening. Papaya (Exotica), slow ripening cultivar PH treatment with Ethrel days after treatment, Differences in maturity accentuated VR Maturity & Ripening Stages GREEN The tomato surface is completely green. The shade of green may vary from light to dark. BREAKERS There is a definite break of color from green to bruised fruit Tannish-yellow, pink or red or % or less of the tomato surface. TURNING Tannish-yellow, pink or red color shows on over % but not more than % of the tomato surface. May, 8 From YK Chan MAFC, MY PINK Pink or red color shows on over % but not more than 9% of the tomato surface. LIGHT RED Pinkish-red or red color shows on over % but red color covers not more than 9% of the tomato surface RED Red means that more than 9% of the tomato surface, in aggregate, is red http://www.tomato.org/ http://www.floridatomatoes.org/
At Packhouse Checker boarding Should never be a problem with vine ripe tomatoes! Maturity Stages of Tomatoes Mature-green =MG MG MG MG MG Breaker At Market Composition of Ripe Grape Tomato Harvested at Stages of Maturity Mangosteen and eating Quality maturity issues Initial Maturity Stage LSD. Weight fruit, g.9.7.9. Red color, hue.8. 7.7 ns Firmness, N force...7. Soluble solids, %.9.7 7..8 Sugars mg/ml Minimum harvest stage should be Stage (pink-orange) Average 7 cvs, Cantwell, 7 Titratable acidity, %.9.8.7.9 Vitamin C mg/ml 9 97 99 ns Color Index Color of Fruit Pale yellow green Blotchy pink Pinkish red Maroon Red Dark maroon violet Violet black Maturity Indices Requirements for establishing Simple, easy to carry out Objective vs subjective indicators Related to quality Related to storage life Represents a progressive change with maturity Permits prediction of maturity from year to year Inexpensive Maturity and Fruit Quality Know the consequences of harvesting at different stages of maturity/ripeness on final eating quality. Make sure workers involved in harvest, selection are well trained to ID correct maturity/ripeness. On behalf of all consumers, please, please! As a consumer, take back poor eating fruit!
Harvest Maturity for Fruits: A balancing Act Too often we err on the side of shelf-life at the expense of good eating quality Too soft Overripe Decay Poor shelf-life Poor flavor Shrivel Never ripens No repeat buys 7