Fruit Ripening and Quality Relationships. Stages of Fruit Development. Informal polling via Socrative

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1 Fruit Ripeig ad Quality Relatioships Iformal pollig via Socrative Dowload the Socrative app o your phoe (Socrative for studet), or coect via the website ( Joi (as a studet) with the room code: FRUITRIPENING You will be able to aswer quiz questios via this iterface. Florece Zakharov Departmet of Plat Scieces fegre@ucdavis.edu INITIATION DEATH DEVELOPMENT GROWTH MATURATION PHYSIOLOGICAL MATURITY RIPENING SENESCENCE 1

2 Developmet series of processes from the iitiatio of growth to death of a plat or plat part. Maturatio The stage of developmet leadig to the attaimet of physiological or horticultural maturity The Physiological maturity The Growth The irreversible icrease i physical attributes (characteristics) of a developig plat or plat part. stage whe a plat or plat part will cotiue developig eve if detached Horticultural maturity The stage of developmet whe a plat or plat part possesses the prerequisites for utilizatio by cosumers CO 2 Ripeig The set of processes that occur from the later stages of growth through the early stages of seescece ad that results i characteristic aesthetic ad/or eatig quality, as evideced by chages i compositio, color, texture, or other sesory attributes. Calvi Cycle Sugars Sugars Glycolysis More carb. Volatiles Acids Pigmets Proteis 2

3 Seescece The last stage of developmet durig which degradatio of biological compoets occur. Physiological Chages Accompayig Seescece of Horticultural Crops Cellular: Loss of chlorophyll, disassembly of chloroplast structure Degradatio of cell walls Altered membrae compositio, loss of fluidity Loss of cellular compartmetatio, release of vacuolar cotets Physiological Chages Accompayig Seescece of Horticultural Crops (cot.) Compositio: Altered sugar cotet, ad switch to alterative substrates for respiratio Net loss of RNA Icreased protease activity, et loss of protei Altered amio acid cotet Respiratio ad ethylee productio rates of climacteric ad o-climacteric fruits Physical Chages Accompayig Seescece of Horticultural Crops Color: Loss of gree color Sythesis of ew pigmets (caroteoids, flavooids) Loss of resistace to pathoges: Developmet of ifectios Lesios Texture: Softeig Wiltig Dryig 3

4 Maturity ad Ripeig Group 1: Fruits that are ot capable of cotiuig their ripeig process oce removed from the plat. Blackberry Loquat Pomegraate Cherry Lychee Prickly pear Grape Madari Rambuta Grapefruit Muskmelos Raspberry Lemo Orage Strawberry Lime Pepper (bell) Tamarillo Loga Pieapple Watermelo Fruit Pomegraate Grape Califoria Miimum Maturity Idices for Selected No-Climacteric Fruits Strawberry SS=soluble solids, A=acidity Miimum maturity idices Red juice color ad below 1.85% acid i juice 1 to 17.5% SS (depedig o cultivar ad productio area) or a SS/A ratio of 20 or higher >3/ of fruit surface showig a pik or red color Apple Mago Persimmo Apricot Nectarie Plum Avocado Papaya Quice Baaa Passio fruit Sapodilla Cherimoya Peach Sapote Guava Pear Tomato Kiwifruit Maturity ad Ripeig Group 2: Fruits that ca be harvested before fully ripe, ad ripeed off the plat Pepper (chili) Fruit Apple Pear (Bartlett) Persimmo SS=soluble solids Califoria Miimum Maturity Idices for Pome Fruits Miimum maturity idices Starch patter, above 10.5 to 12.5% SS ad below 18 to 23 lb-force firmess (depedig o cultivar) Yellowish-gree color, ad/or below 23 lbforce firmess, ad/or above 13% SS Yellowish-gree to orage color (depedig o cultivar)

5 Quality Attributes of Fruits Perceptio of Quality Ø Vary depedig o protagoist i PH chai Ø Cosumer-cetric quality ultimately drives marketability ad sales Ø Overall cosumer acceptace strogly correlated with Flavor acceptace Our sesory systems are resposible for geeratig a iteral represetatio of the outside world, icludig its chemical (taste ad olfactio) ad physical (mechaical, soud, visio ad temperature) features. Whe evaluatig the quality of the foods we eat, we use the complete array of our sesory system (chemical ad physical seses) ad itegrate this iformatio to formulate a judgmet. Sesory Attributes of Foods Sesory Attributes of Foods Appearace Appearace Taste First attributes perceived Odor/smell/aroma Irritatio/pai Texture/mouthfeel Temperature Flavor Shape Color Strogly-set expectatios Emotioal cootatios 5

6 Sesory Attributes of Foods Taste Our sese of taste is i charge of evaluatig the utritious cotet of food ad prevetig the igestio of toxic substaces. Taste is a sesatio perceived i the mouth, more specifically o the togue. Sweet Salty Bitter Sour (acidic) Umami (protei savory) 5 TASTES Are taste prefereces iate or leared? Socrative poll room umber: FRUITRIPENING A. Iate (= we are bor preferrig sweet/salty/ umami tastes) B. Leared (= as we grow up, we lear to prefer sweet/salty/umami tastes) Fruit Compositio ad Taste Taste vs. Sugar/Acid Ratio Quality Class of compoud Examples Sweet Sugars Sucrose, fructose, glucose Sour Acids Citric acid, malic acid, tartaric acid Bitter Alkaloids, Pheolics, Terpeoids, some proteis Narigi, cucurbitacis, limooids Salty Ios Sodium, calcium Umami Amio acids Glutamate, aspartate Acids Low Moderate to High Low Isipid, tasteless Sour, tart Soluble solids measured by a refractometer = sugars, orgaic acids, soluble pectis, athocyais, pheolic compouds, ascorbic acid Sugars High Sweet Best taste combiatio Need quick methods of measurig total sugars ad titratable acidity

7 Are smell/scet prefereces iate or leared? Sesory Attributes of Foods Aroma Socrative poll room umber: FRUITRIPENING Aroma (or smell or odor) is the sesatio perceived whe volatile compouds are draw ito the ose. A. Iate (we are bor preferrig/rejectig certai smells) B. Leared (as we grow up, we lear to prefer/reject certai smells) Sesory Attributes of Foods The Aroma of a Strawberry Over 200 volatile compouds!! Texture / Mouthfeel Astrigecy (tais, calcium oxalate) Sese of touch (mechaoreceptors) Guiard,

8 Sesory Attributes ad Fruit Compositio Sesory Methodology All fruit compoets (sugars, acids, volatiles, etc ) combie to geerate a uique sesory experiece for the cosumer. Physical methods ca give accurate measuremets of fruit compositio but it is difficult to relate these measuremets to fruit quality without iformatio about sesory perceptio. Aalytical tests Differece? What is it? How strog is it? Descriptive aalysis Traied judges Sesory Methodology Objective measuremets ad Quality predictio Developmet o the plat Cosumer tests Preferece, likig, purchase itet Attitudes, beliefs Ethography Utraied cosumers Developmetal program Physiological processes (metabolism) Chages i compositio Geetic/evirometal/ cultivatio factors à Harvestig at maximum potetial Postharvest Life (?) Altered physiological processes (metabolism) Chages i compositio Geetic/evirometal/ hadlig factors à Attaiig ad retaiig maximum quality 8

9 7.0 Effect of Maturity ad Ripeess o Selected Sesory Attributes R² = Mas Rico Texture Likig Score.5.0 R² = Mea Sesory Score Flavor Likig Score Ø Overall cosumer acceptace (ad repeat buy) strogly correlated with Flavor acceptace.0 R² = Navigator Thuderbird Sweet taste 8.5 % SSC or Brix Perceptio of melo quality Appearace Likig Score Case study: PL PD GS OS S1 12 Soluble Solids Cotet PL PD GS OS S Overall Likig Score Early mature Fully ripe Early mature Fully ripe 9

10 Fruit Volatile Aalysis Usig a Electroic Nose Nodestructive Quality Sesig Needs Ø Degree of freshess (time sice harvest) Ø Prior exposure to ethylee (cocetratio x duratio x temperature) Ø Prior exposure of chillig-sesitive commodities to chillig coditios (temperature x duratio) Ø Iteral traslucecy / browig Ø Mealiess (lack of juiciess) Ø Acidity / utritioal value Ø Aroma (volatiles) Questios? 10