Dr. Sreekanta Sheel

B.Sc. Agril. Engg - with major in Food TechnologyM.Sc. (Agril. Engg) in Food Technology,

Ph.D in Food Technology

Logistics (Transportation and Storage) ExpertNational Agricultural Technology Project

(Funded By: The World Bank, IFAD and Govt. of Bangladesh}

Factors affecting the FreshnessFactors affecting the Freshness of Fresh of Fresh Horticultural ProducesHorticultural Produces

Some Low-cost Storage Techniques for Some Low-cost Storage Techniques for PerishablesPerishablesMinimal processing of Fruits and VegetablesMinimal processing of Fruits and Vegetables

Out line of the presentationOut line of the presentation

Horticultural Produces are Perishable!Horticultural Produces are Perishable!

Extremely Large loss due to above factExtremely Large loss due to above fact Horticulture produces are different in Horticulture produces are different in

character even from one piece to anothercharacter even from one piece to another Amount of gas released after harvesting Amount of gas released after harvesting

varies widelyvaries widely Sensitivity to gas released by themselves Sensitivity to gas released by themselves

also differ from one to another also differ from one to another

Factors affecting the FreshnessFactors affecting the Freshness of of Fresh Horticultural ProducesFresh Horticultural Produces

Temperature Humidity Gas atmosphere Volatiles adsorption

Temperature

Degree of influence varies from one to anotherDegree of influence varies from one to another Quality deteriorates with increase in Quality deteriorates with increase in

TemperatureTemperature Minimizing temperature rise in packages is a Minimizing temperature rise in packages is a

very important element for preservation of very important element for preservation of Quality of packaged Fresh ProduceQuality of packaged Fresh Produce

Chilling injuryChilling injury

Humidity

Moisture Content of most products are 90% or moreMoisture Content of most products are 90% or more Loss of 5%MC will result extreme loss of commodity Loss of 5%MC will result extreme loss of commodity

valuevalue Water Evaporation mechanism differs from one to Water Evaporation mechanism differs from one to

anotheranother 5% MC loss is the maximum limit that can be 5% MC loss is the maximum limit that can be

tolerated in terms of commodity valuetolerated in terms of commodity value Methods to keep MC within limit: Methods to keep MC within limit:

1. Using humidifier- (difficult in open shelf !)1. Using humidifier- (difficult in open shelf !)

2. Package should give protection for water loss2. Package should give protection for water loss

Gas Atmosphere Influence of OxygenInfluence of Oxygen Normal respiration Normal respiration

Even when O2 concentration in the environment falls fairy Irregular respirationIrregular respiration:

Leads to Physiological disturbance-resulting in corruption, when O2 concentration is below the “Threshold Valued (A boundary, where something starts or ends).” it is related to the CO2 concentration. Threshold value varies from one to another

Low OLow O22 concentration but above “Threshold Valued” concentration but above “Threshold Valued” extends the storable period because of Respiration Suppressing Effects

Correct selection of packaging filmCorrect selection of packaging film To ensure adequate balance of O2 and CO2 Use of 1-MCPUse of 1-MCP To preserve freshness, 1-MCP can be used but -used but -RESEARCH NEEDED for RESEARCH NEEDED for

indigenous commodities!indigenous commodities!

Influence of Ethylene Gas

Air mixed with ethylene promotes colouring/ Air mixed with ethylene promotes colouring/ ripeningripening

It is believed 0.1 ppm ethylene in atmosphere It is believed 0.1 ppm ethylene in atmosphere causes ageing & colour changecauses ageing & colour change

Removal of ethylene will extend storage periodRemoval of ethylene will extend storage period

Influence of Carbonic Acid Gas

High Carbonic Acid gas concentration-suppress High Carbonic Acid gas concentration-suppress Respiration- favourable effect on StorageRespiration- favourable effect on Storage

Abnormality to metabolic physiology including Abnormality to metabolic physiology including respiration when the concentration reaches respiration when the concentration reaches threshold levelthreshold level

Some Low-cost Storage Techniques for Some Low-cost Storage Techniques for PerishablesPerishables

Zero Energy Evaporative Cooler CoolBot Technology Storage in Film package

- Passive Modified Atmosphere Packaging - Passive Modified Atmosphere Packaging (PMAP)(PMAP)

Storage of Horticultural Produces at Zero Energy Evaporative Cooler (IARI Model)

CoolBot technology for small scale cold rooms A small-scale option of cold room using a modified room air conditioner (developed by Boyett and Rohrbach in 1993.)

The cost of installation of a CoolBot technology for a 20 m2 small scale cold rooms having capacity of 6 MT pptato is around US$ 5000.00 only. The coolbot technology utilizes a typical window type air conditioning unit to create a cold room capable of 0oC temperatures.

Inside the Coolbot cold room

Source: WFLO Grant Final Report,2010 Further Information: http://www.storeitcold.com/

Costs and Benefits of the Small-scale Cold room with Costs and Benefits of the Small-scale Cold room with CoolBot technology in India for Potato Storage CoolBot technology in India for Potato Storage

COSTS COSTS 20m20m2 2 Cold room with air conditioner & CoolBot (6MT capacity) Cold room with air conditioner & CoolBot (6MT capacity) $4300 $4300 Capital costs (initial investment assuming no labor cost) Capital costs (initial investment assuming no labor cost) $4300 $4300 Electricity for initial cooling ($85 per MT, $0.09/kWh) Electricity for initial cooling ($85 per MT, $0.09/kWh) $ 510 $ 510 Electricity $18 per month for 3 months, $0.09/kWh at 7 C Electricity $18 per month for 3 months, $0.09/kWh at 7 C $ 54$ 54World Food Logistics Organization Grant Number 52198 257 World Food Logistics Organization Grant Number 52198 257 Recurring costs Recurring costs

$564 $564

Relative total cost Relative total cost $ 4864* $ 4864* EXPECTED BENEFITS EXPECTED BENEFITS % losses % losses 30% 30% 5%* 5%* Amount for sale Amount for sale 4200 kg 4200 kg 5700 kg 5700 kg Market value/kg Market value/kg $0.10 $0.10 $0.40 $0.40 Total market value of one load Total market value of one load $420 $420 $ 2280 $ 2280 Market value – recurring costs Market value – recurring costs $420 $420 $ 2280- $564= $1716 $ 2280- $564= $1716 Relative profit for one load stored for 4 months Relative profit for one load stored for 4 months + $ 1296 + $ 1296

A passive modified atmosphere is created within the package by the respiration process of the fresh-cut produce, combined with the permeability of the package. MAs by definition are atmospheres that differ in composition from that of normal air. Typically, MAs consisting of low oxygen and high CO2 concentrations are used to reduce respiration

Passive Modified Atmosphere Packaging Passive Modified Atmosphere Packaging (PMAP)(PMAP)

 What is Minimal Processing? Minimal processing for agricultural crops refers to a method in which as much of the original product as possible remains in the finished product.  

Commodity Minimally processed

Processed

Rice De-husked paddy

Parboiled, De-husked, Removal of bran layer and germ, enrichment with vit and minerals, etc.

Mango Peeled Mango Slices

Mango leather (Pulping, blanching, cooling, sulphiting, adding sugar and citric acid and other additives and drying

Ready to eat products Ready to eat products Given minimal processing treatments Given minimal processing treatments Have the attributes of convenience Have the attributes of convenience Fresh-like quality (aroma, flavour and nutrients are Fresh-like quality (aroma, flavour and nutrients are retained) retained) More perishable than the intact produce as these are More perishable than the intact produce as these are subjected to physical stress such as peeling, cutting, subjected to physical stress such as peeling, cutting, slicing, etc slicing, etc Tissues are still living Tissues are still living The preparation entails physical wounding- respiration, The preparation entails physical wounding- respiration, ethylene production and biochemical changes - limit the ethylene production and biochemical changes - limit the shelf lifeshelf life  

Nature of Minimally Processed Fruits Nature of Minimally Processed Fruits

Limited as it faces the following factors deeply:Limited as it faces the following factors deeply:

11. Microbial spoilage . Microbial spoilage 2. Desiccation 2. Desiccation 3. Oxidative browning 3. Oxidative browning 4. Loss of colour, bleaching 4. Loss of colour, bleaching 5. Loss of textural integrity 5. Loss of textural integrity 6. Off-flavour or off odour development 6. Off-flavour or off odour development

Shelf-life of Minimally Processed Product Shelf-life of Minimally Processed Product

Market demand high. as consumers more Market demand high. as consumers more conscious in their food choices but have conscious in their food choices but have less time to prepare less time to prepare

The market outlet for minimally processed The market outlet for minimally processed products has expanded from traditional to products has expanded from traditional to exclusive outlets such as supermarkets, exclusive outlets such as supermarkets, hotels, airlines catering services hotels, airlines catering services

Market PotentialMarket Potential

HarvestingHarvestingFruit maturity: Selection of the optimum maturity is essential to provide Fruit maturity: Selection of the optimum maturity is essential to provide

the best combination of eating quality & postharvest life. the best combination of eating quality & postharvest life. Receiving at the processing facilityReceiving at the processing facility Pre-coolingPre-cooling

Minimal Processing Operations Minimal Processing Operations (from harvest to market)(from harvest to market)

Washing and disinfectionWashing and disinfectionFor vegetable wash water the parameters may be used:Temperature (0-5oC),pH (4.5-5.5) [Adding acidulent]Chlorine concentration (50-100 ppm), Oxidation reduction potential (ORP) (650-750 ppm). During the washing process any defective produce must be removed and discarded.

In small processing plants, knives are used to trim In small processing plants, knives are used to trim and peel fresh produce. Large processing plants and peel fresh produce. Large processing plants make use of abrasive peelers and automated make use of abrasive peelers and automated trimmers to accelerate the process. trimmers to accelerate the process.

Cutting operationsChopping boards and knives are used to create Chopping boards and knives are used to create the desired size and shape for finished products. the desired size and shape for finished products. Research has shown that using a sharp knife Research has shown that using a sharp knife reduces physical damage to cut fruits and reduces physical damage to cut fruits and vegetables in that less stress is observed in the vegetables in that less stress is observed in the cells of produce cut with a sharp knife. cells of produce cut with a sharp knife.

Peeling, trimming and deseeding

Cutting : Use Suitable Tools Cutting : Use Suitable Tools -Accelerates respiration process -Mechanical shock to tissue -Bruises, cracks, fractures in tissue -Removal of protective epidermal layer -Alter gas diffusion -Provides entry for contaminants -Cell fluids on cut surface -Reduced gas diffusion -Provides substrates for microbes -Exposure to contaminants -Physical & chemical change

Sorting for defectsSorting for defects

Rinsing of pre-cut fruits and vegetablesIt is recommended that only water of the highest quality be used for the final rinse of pre-cut fruits and It is recommended that only water of the highest quality be used for the final rinse of pre-cut fruits and vegetables. Many operations inject chlorine as a disinfectant along with acid in order to maintain a pH range vegetables. Many operations inject chlorine as a disinfectant along with acid in order to maintain a pH range of 4.5-5.5 and to assure the effectiveness of chlorine. of 4.5-5.5 and to assure the effectiveness of chlorine.

DippingProduce can be optionally dipped in a solution of an acidulant/antioxidant blend consisting of a combination Produce can be optionally dipped in a solution of an acidulant/antioxidant blend consisting of a combination of ascorbic acid/citric acid for example, or in an anti-softening agent such as calcium chloride.of ascorbic acid/citric acid for example, or in an anti-softening agent such as calcium chloride.

Prevention of Oxidative BrowningPrevention of Oxidative BrowningRate of respiration high after cutting / cutting size Rate of respiration high after cutting / cutting size Refrigeration (slows enzymatic reactions) Refrigeration (slows enzymatic reactions) Exclusion of oxygen (CA, MAP, edible coating) Exclusion of oxygen (CA, MAP, edible coating) Inhibition of Polyphenol Oxidase (PPO) Inhibition of Polyphenol Oxidase (PPO) Use of reducing agents (ascorbic acid, etc) Use of reducing agents (ascorbic acid, etc)   Treating with Ascorbic Acid  Oxidative browningTreating with Ascorbic Acid  Oxidative browning– – is caused by the PPOis caused by the PPO   Ascorbic acid used to prevent oxidative - browning as:Ascorbic acid used to prevent oxidative - browning as:– – It plays the unique role of a reducing agent (convert phenolic cpd It plays the unique role of a reducing agent (convert phenolic cpd to their reduced form)to their reduced form)– – It lowers the pH of the productIt lowers the pH of the product  

Treatment with CoatingTreatment with Coating  The use of edible coating create a barrier that can retard loss of desirable The use of edible coating create a barrier that can retard loss of desirable flavour volatiles and water vapour, while restricting the exchange of CO2 and flavour volatiles and water vapour, while restricting the exchange of CO2 and O2. These will create MA slow down respiration & ethylene production O2. These will create MA slow down respiration & ethylene production maintain the quality & shelf life extension of minimally processed products maintain the quality & shelf life extension of minimally processed products

Drying_ Use of conveyor shakers to remove water through a mesh. The cut fruit or vegetable vibrates on the conveyor mesh._ Air drying on conveyors with forced air or polar wind used to blow excess water off the surface of the wet produce._ Spin-drying baskets, both automated and manual, that make use of centrifugation to remove excess water.

Packaging/LabelingMAP reduces the respiration rate of produce and thus slows the rate of spoilage. In addition, it creates anaerobic conditions or high carbon dioxide and low oxygen levels in the pack, to extendfresh produce shelf-life. Oriented polypropylene (OPP) is generally used in the MAP of fresh-cuts. Other packaging films used include perforated, thin, low density polyethylene (LDPE) and ethylene vinyl acetate.

Suitable Packing SystemSuitable Packing SystemProtect the productEnsure food SafetyMaintain qualityAttract consumers Major Requirement for Proper PackagingMajor Requirement for Proper PackagingControl moisture loss, gas transfer, Protection against external physical or mechanical damage -Compliance with regulatory requirements and guidelines -Cost effective -Facilitate transport, handling, storage and marketing  

Types of PackagesTypes of PackagesRigid packages•Reduce physical injury•Provide sufficient gas exchange Polypropylene containerPolypropylene container» Easy to handle • packing faster • can be stacked  Bulk Package • Low temperature - provide cool environment to preserve the quality & freshness during transportation & marketing  

Temperature Affects All Causes of Deterioration 1. Metabolic changes; respiration, ethylene, texture, aroma, etc 2. Transpiration 3. Mechanical injury 4. Physiological disorders 5. Decay, microbial growth  Signs of deterioration in fresh cut produceSigns of deterioration in fresh cut produce • Bruished –packaging too tight/rough handling • Wilting -excessive drying/water loss • Mushiness -excessive tissue softening • Development of offcolour-enzymatic browning • Undesirable odour/fermented aroma-accumulation of ethanol

Minimal Processing of Pineapple and JackfruitMinimal Processing of Pineapple and Jackfruit• • Wider range for market planningWider range for market planning• • Convenient to eat/carry: Convenient to eat/carry: • • Provide more uniform & constant quality Provide more uniform & constant quality • • Require less storage space : Require less storage space : • • Allow consumer to inspect closely & reassure of the quality Allow consumer to inspect closely & reassure of the quality • • Ensure of product safety Ensure of product safety • • Overcome waste disposal problems at the importer ends. Overcome waste disposal problems at the importer ends. • • The consumer can see the product to be eaten The consumer can see the product to be eaten • • Reassure quality and freshness (retain colour, flavour & aroma Reassure quality and freshness (retain colour, flavour & aroma   Export PotentialExport PotentialAt 2At 2ooC, Pineapple, 2wks and Jackfruit-3 wksC, Pineapple, 2wks and Jackfruit-3 wksAir shipment - Air shipment - Sea shipment –Sea shipment –

Scope for retail packaging - Minimally processed fruits and vegetables with modified atmosphere packaging (MAP)

Minimally processed fruits and vegetables with modified atmosphere packaging (MAP) using tray

Vacuum Packaging (Vac Pack)

ConclusionConsumer demand for convenience and added value Consumer demand for convenience and added value

means that minimally processed fruits with means that minimally processed fruits with extended shelf life will play a significant role in the extended shelf life will play a significant role in the FRUIT and VEGETABLES INDUSTRY in the future. -FRUIT and VEGETABLES INDUSTRY in the future. -Application of strict sanitation in processing, Application of strict sanitation in processing, improved technology in packaging, and intense improved technology in packaging, and intense commitment to strict attention to maintaining commitment to strict attention to maintaining correct low temperatures throughout the cold chain correct low temperatures throughout the cold chain -from distribution, storage, and display to handling -from distribution, storage, and display to handling and use by the consumer. and use by the consumer.

Success will ultimately depend on providing a safe, Success will ultimately depend on providing a safe, wholesome product with FRESH-LIKE quality at the wholesome product with FRESH-LIKE quality at the consumer’s table.consumer’s table.