FAO study on Postharvest losses of

cassava, mango and tomato in Trinidad

and Tobago, Guyana and St. Lucia

Majeed Mohammed and Kelvin Craig

OUTLINE

• Introduction: Cassava , Mango and Tomato value chains and storage potential

• Methodology (FAO 4-S Approach, Diei-Quadi and Mgawe, 2012)

• Results: causes of qualitative and quantitative losses

• Postharvest loss management strategies

Perishable nature • Variations in maturity, shape and size.

• Harvesting methods and field handling practices.

• Prone to physical damages and wounding stress.

• Susceptibility to physiological disorders.

• Implications of pathological and entomological damages on quality attributes.

• Opportunities to develop value-added products to alleviate postharvest losses.

Objectives

• To systematically assess and characterize the cassava, mango and tomato value chains in Trinidad and Tobago, Guyana and St. Lucia using field based measurements at the farm, wholesale and retail markets.

• To identify where quality changes and postharvest losses occur and to measure and categorise the level of deterioration and their causes at various critical loss points (CLP), and more importantly, to determine where realistic solutions exist for reducing these losses in the value chain.

Methodology

FAO 4-S Approach, Diei-Quadi and Mgawe, 2012 Screening: inventory postharvest losses, identify CLPs, data collection tools. Survey: interviews with key stakeholders in FSC, in dept analysis of FSC. Sampling: Load Tracking and Sampling Assessment, tracking and tracing activities within postharvest system components. Synthesis: monitoring mechanism for food losses; an investment programme to reduce food losses; and a food Loss Reduction Strategy.

Waxing

Cured roots

Cured roots Uncured roots

CASSAVA PRODUCER

↓

Harvest

Cassava

7 – 18 months

↓

Field selection

↓

Packing in bag,

crates

↓

Load on

transport

vehicle

Transport

Soak overnight

in 700ppm

chlorinated water

↓

Power wash

to remove dirt

↓

Rinse in 700ppm

Chlorinated

water

↓

Cut into logs

↓

Seal package

↓

Freeze at -18°C

RETAILER

↓

Wash

↓

Storage

↓

Grade

↓

Moist

Medium

RETAIL

MARKET

WHOLESALE

MARKET

WHOLESALER

RETAIL MARKET

PROCESSOR Logs, flakes, cubes,

farine, flour, puree,

starch, gari, chips,

cassareep, pone mix

CONSUMER

NA

TIO

NA

L P

AC

KIN

GH

OU

SE

CLP#1

CLP#2

CLP#3

Table 1. Postharvest losses of cassava at farmer/retailer in Trinidad and Tobago --------------------------------------------------------------------------------------------------------------------------------

-- Critical Loss Postharvest losses (%) Farmer/Retailer Points (CLP) ------------------------------------------------------------------------------------------------------------------------------ Physical Physiological Pathological Losses Quality --------------------- and (%) score VS-1 VS-11 Entomological ------------------------------------------------------------------------------------------------------------------------------------------ Field Harvest 1.5 0.0 0.0 2.0 3.5 8.0 CLP#1 Packhouse 1.0 0.0 1.0 1.5 3.5 6.0 CLP#2 Retail Marketing CLP#3: Day 2 0.5 1.0 0.0 0.5 2.0 6.0 Day 4 1.0 1.0 1.0 2.0 5.0 5.0 Day 6 1.0 1.5 2.5 1.0 6.0 4.5 Losses 5.0 3.5 4.5 7.0 20.0 ----------------------------------------------------------------------------------------------------------------------------------------- Farmer who retails at municipal, roadside or mobile markets Data taken from 2-3 bags (84-96 lbs) x 10 times Ambient conditions: 28-32C and 65-75% RH. VS: Vascular Streaking. Quality score: 1-9 with 1=poor, 9=excellent.

Table 2. Postharvest losses at farmer/retailer in Guyana --------------------------------------------------------------------------------------------------------

---

Critical Loss Postharvest losses (%) Farmer/Retailer Points (CLP) ------------------------------------------------------------------------------------------------------------------------------ Physical Physiological Pathological Losses Quality --------------------- and (%) score VS-1 VS-11 Entomological ------------------------------------------------------------------------------------------------------------------------------------------------ Field Harvest 3.0 0.0 0.0 3.5 6.5 8.0 CLP#1 Packhouse 1.0 0.0 0.0 1.0 2.0 8.0 CLP#2 Retail Marketing CLP#3: Day 2 1.5 1.0 0.0 0.5 3.0 6.0 Day 4 1.0 1.0 1.0 1.0 4.0 5.5 Day 6 1.5 1.5 2.5 2.0 7.5 4.5 Total Losses (%) 8.0 3.5 3.5 8.0 23.0 ----------------------------------------------------------------------------------------------------------------------------------------------- Farmer who retails at municipal, roadside or mobile markets Data taken from 2-3 bags (84-96 lbs) x 10 times. Quality score: 1-9 with 1=poor, 9=excellent Ambient conditions: 28-32C and 65-75% RH. VS: Vascular Streaking

Cassava brown streak

Root rot disease emergence is often favoured by waterlogged, poorly-draining soils

Botryodiplodia theobromae

Rotting tubers cut open to reveal discoloration

Discoloration on tuber surface caused by root rot

Scales on cassava stem

Scales on cassava tubers

Postharvest losses and wastes reduction strategies

MAP

CHILLING INJURY NO CHILLING INJURY

Postharvest losses and waste reduction strategies for cassava

Type of

Postharvest loss

@ Packhouse CLP2#2

Processor (Frozen cassava logs)

Sandy soil

Clay soil

Soaking /Washing/

Sanitizer (peel, dirt)

9.0d 16.5g

Fresh-cut into logs

(broken pieces,

distal and proximal ends)

13.5f 12.0e

Physiological:VS-1

VS-11

3.5b

8.0d

1.0a

2.0ab

Pathological and

Entomological

5.5c 6.0c

Total Losses (%) 34.0h 37.5i

SOAKED OVERNIGHT POWER WASHED

PEELED LOGS FROZEN LOGS

INSECT DAMAGE

Ungraded desiccated roots

Grading scheme

Tracing production of cassava farine production in St. Lucia and Guyana

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Processing flow Quality control and uses

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Harvested roots Select fresh, mature cassava roots without rots (60kg)

Washing Remove dirt and damaged roots (3.5%)

Peeling Peel skin and remove woody tips (3.2%)

Rinsing Wash in clean water to remove pieces of peel

and sand

Grating To macerate or crush pulp

Pressing (< 50 % Moisture) Macerated pulp squeezed to remove cassava juice water

which is boiled to produce cassarep :flavour enhancer,

preservative and colourant (5 litres)

Sifting Sieved to separate fibrous materials to

control particle size

Parching Parched in heated flat pan until light brown

colour develops (5.3%)

Farine A second sieving is optional to remove coarse

materials (Guyana 20 kg, St. Lucia 25 kg)

Packaging Farine is packaged in sealed aluminium pouches

or in low density polyethylene bags

Consumer Used to make porridge, breads, and thickening agent

Postharvest losses of tomatoes

CLP#1 CLP#2 CLP#3 Total losses

Trinidad &Tobago 7 8 12 27

Guyana 11 10,5 12,5 34

St. Lucia 7 8 5 20

0

5

10

15

20

25

30

35

40P

ost

harv

est

loss

es %

TT and Guyana

CLP#1: Harvest; CLP#2:

Packhouse; CLP#3: Retail

Market

St. Lucia

CLP#1: W/Sale Co-op.;

CLP#2:

Mkg. Board Retail Outlet;

CLP#3: Retail Market

Causes for tomato postharvest losses --------------------------------------------------------------------------------------------------------------------------------------------------------

Types of Tomato postharvest losses (%) Losses -----------------------------------------------------------------------------------------------------------------------------

Trinidad &Tobago Guyana St. Lucia

------------------------------- -------------------------------- ---------------------------------------

CLP#1 CLP#2 CLP#3 CLP#1 CLP#2 CLP#3 CLP#1 CLP#2 CLP#3

--------------------------------------------------------------------------------------------------------------------------------------------------------

Physical 1.5 1.0 2.5 3.5 3.0 3.0 2.0 3.0 3.0

Physiological 2.5 2.0 4.0 3.0 2.0 2.5 2.0 1.5 0.5

Pathological &

Entomological 3.0 5.0 5.5 4.5 5.5 7.0 3.0 3.5 1.5

Total 7.0 8.0 12.0 11.0 10.5 12.5 7.0 8.0 5.0

Total losses (%) 27.0 34.0 20.0

----------------------------------------------------------------------------------------------------------------------------- ------

TT and Guyana: CLP#1: Harvest; CLP#2: Packhouse; CLP#3: Retail Market

St. Lucia: CLP#1: W/Sale Co-op.; CLP#2:Mktg. Board Retail Outlet; CLP#3: Retail Market

PHL at CLP#1 Harvest

Transportation linkages and logistics

Physical damages at CLP#1

Secondary infection from finger nail damage

Secondary infection from compression

Secondary infection from abrasions and bruises

PHL at Packhouse CLP#2

Catface

Puffiness, poor seed set due to poor pollination Desiccation and CI pitting

Desiccation

Blotchy ripening

Russeting

Cuticle cracking around stem

Chilling injury

Pathological losses at CLP#2 and CLP#3

Entomological losses at CLP#2 and CLP#3

Stink bug damage Silverleaf white fly

Wilt virus-vectored by thrips Spider mite damage

White fly infection

Tomato fruit worm Cloudy spot from stink bug damage Black mold via skin wound

Yellow shoulder

Postharvest losses and waste reduction strategies

Packinghouse facilities

Value added products

Value added products

Table 5.2.2. Sensory evaluation of tomato value-added product roasted

tomato choka.

Variables Sensory evaluation

-------------------------------------------------------------------------------------------

Colour Appearance Texture Taste Flavour General

Acceptability

UWI

Students 2.0 2.5 2.5 3.5 3.5 3.0

(n= 44)

General 3.0 2.5 3.0 3.0 3.0 3.5

Public

(n= 36)

Supermarket

Consumers

(n= 39) 30 3.0 2.5 3.5 3.5 3.5

Postharvest losses of mango ------------------------------------------------------------------------ Critical Loss Mango postharvest losses (%)

Points (CLP) ----------------------------------------------------------------------------------------------

Trinidad &Tobago Guyana St. Lucia

cv. Julie cv. Buxton spice cv. Julie

---------------------------------------------------------------------------------------------------------------------

CLP#1 5.0 15.0 8.0

CLP#2 13.0

CLP#3 2.0

CLP#4 12.0 17.0

Total losses (%) 17.0 32.0 23.0

---------------------------------------------------------------------------------------------------------------------

TT and Guyana

CLP#1: Harvest; CLP#4: Packhouse;

St. Lucia

CLP#1: W/Sale Co-op.; CLP#2:Mktg. Board Retail Outlet; CLP#3: Retail Market

Causes for mango postharvest losses --------------------------------------------------------------------------------------------------------------------------------------------------------

Types of Mango postharvest losses (%) Losses -----------------------------------------------------------------------------------------------------------------------------

Trinidad &Tobago Guyana St. Lucia

------------------------------- -------------------------------- ---------------------------------------

CLP#1 CLP#4 CLP#1 CLP#4 CLP#1 CLP#2 CLP#3

--------------------------------------------------------------------------------------------------------------------------------------------------------

Physical 3.0 2.5 6.0 4.0 3.0 4.5 0.5

Physiological 0.0 2.0 2.0 4.0 3.0 4.0 1.0

Pathological &

Entomological 2.0 7.5 7.0 9.0 2.0 4.5 0.5

Total 5.0 12.0 15.0 17.0 8.0 13.0 2.0

Total losses (%) 17.0 32.0 23.0

----------------------------------------------------------------------------------------------------------------------------- ------

TT and Guyana: CLP#1: Harvest; CLP#4: Packhouse

St. Lucia: CLP#1: W/Sale Co-op.; CLP#2:Mktg. Board Retail Outlet; CLP#3: Retail Market

Postharvest losses of mango value added products

------------------------------------------------------------------------------------------------------------------Types of PHL Trinidad and Tobago Guyana

cv Long cv Buxton spice

--------------------------------------------- ------------------------------------------------

CLP#2 (kuchelar) CLP#3 (Frozen slices) CLP#2 (kuchelar) CLP#3 (Frozen slices)

------------------------------------------------------------------------------------------------------------------------------------------------------

Physical

Damage 10.0 8.5 10.5 9.5

Physiological

Disorders 2.0 3.0 3.0 2.5

Pathological and

Entomological 12.0 12.0 6.0 9.0

Skin and seed 23.0 15.0 20.0 9.5

Total losses (%) 47.0 38.5 39.5 30.5

----------------------------------------------------------------------------------------------------------------------------- -----

Kuchelar: skin and seed with endosperm not utilized

Frozen slices: skin and seed endosperm not utilized

Physical losses at CLP#1

Transportation logistics

Physiological losses at CLP2 & 3

Pathological losses at CLP#2 & 3

Entomological losses at CLP#2 & 3

Strategies to reduce postharvest losses and waste

Latex stain management (Brecht 2013)

Mango value-added products