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Factor influencing food deterioration

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Presentation on theme: "Factor influencing food deterioration"— Presentation transcript:

1 Factor influencing food deterioration
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2 quality products are produced in the fields!
but, the quality of a product is maintained and enhanced during its harvest and post-harvest management. Presentation 3.2

3 Food Deterioration and its Causes

4 What is food deterioration, and how can food science minimize its effects?

5 Food deterioration includes:
changes in organoleptic quality (how something is perceived by a sensory organ) nutritional value food safety aesthetic appeal color texture flavor To some degree, all foods undergo deterioration after harvest. The role of food science is to minimize negative changes as much as possible.

6 Product quality at harvesting
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7 Product quality after improper mechanical grading process.
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8 Now it is waste...how many opportunities
have been lost! Presentation 3.2

9 Loss in quantity and quality between harvest and consumption:
LOSS OF HORTICULTURAL CROPS Loss in quantity and quality between harvest and consumption: 5 - 25% in developed countries % in developing countries

10 CATEGORIES OF DETERIORATION
any change in the appearance, smell, or taste of a food product that makes it unacceptable to the consumer. Food DETERIORATION results in economic loss to producers, distributors, and even consumers.

11 Causes of Food Deterioration
Phisiology Microbial spoilage Chemical reactions can also reduce food quality Exposure to air or light (oxidative rancidity) Reactions caused by enzymes in the food leading to off-flavors Other chemical reactions/interactions Cold storage temperatures can minimize chemical re

12 Table 1. Useful Shelf Life at 70 F
Food Days Meat to2 Fish to 2 Poultry to 2 Dried, smoked meat 360+ Fruits to 7

13 Table 1. Useful Shelf Life at 70 F
Food Days Leafy vegetables 1 to 2 Root Crops 7 to 20 Dried seeds

14 The three general categories of food deterioration are:
Physical Chemical Biological Factors that cause food deterioration include: light, cold, heat, oxygen, moisture, dryness, other types of radiation, enzymes, microorganisms, time, industrial contaminants and macroorganisms (insects, mice, and so on).

15 WHAT CAUSES FOOD DETERIORATION?
Deterioration can be caused by one or more of the following: Microorganisms such as bacteria, yeast and molds; Activity of food enzymes; Infestations by insects, parasites and rodents; Inappropriate temperatures during processing and storage; Gain or loss of moisture; Reaction with oxygen; Light; Physical stress or abuse; and Time.

16 BIOLOGICAL CHANGES CAN INCLUDE
WILTING DISCOLORATION SLIME FORMATION/COAGULATION OFF-FLAVORS OFF-ODORS EXCESSIVE MICROBIAL NUMBERS/TOXINS

17 CHEMICAL CHANGES CAN INCLUDE
OFF-FLAVORS OFF-ODORS DISCOLORATION (BROWNING, FADING) TEXTURAL CHANGES CONTAINER INTERACTIONS

18 CONTROL OF CHEMICAL CHANGES
AVOID EXCESSIVE HIGH TEMPERATURES AVOID EXPOSURE TO LIGHT MINIMIZE EXPOSURE TO OXYGEN PROPER PROCESSING TO MINIMIZE MAILLARD REACTIONS DURING PROCESSING

19 Reduce losses: 1. Understand biological en environmental factors involved in deterioration 2. Use postharvest techniques that delay senescence and maintain the best possible quality Presentation 3.2

20 BIOLOGICAL FACTORS INVOLVED
IN DETERIORATION 1. Respiration 2. Transpiration 3. Growth and development 4.Compositional changes 5. Physiological breakdown .6.Pathological breakdown 7. Physical damage Nest of gray mould

21 ENVIRONMENTAL FACTORS INFLUENCING DETERIORATION
2. Relative humidity 3. Atmosphere composition 4. Ethylene 5. Light 1. Temperature Leather rot Rhizopus rot

22 Principles of postharvest management of FFV
Product quality maintenance (reduce loses) Generate product added value Presentation 3.2

23 Key processes during the
Fruits and vegetables as PERISHABLE products Key processes during the post-harvest- life : Respiration . Transpiration . Maturity process. Presentation 3.2

24 Typical life cycle of living tissues
Development/growth (metabolic,biosynthetic reactions) Maturation Ripening Senescence (catabolic, degradative reactions) Deterioration

25 BIOCHEMICAL REACTIONS OF RESPIRATION

26 Plants have the ability to utilize energy from sunlight for synthesis of carbohydrates using CO2 and H2O in the air; photosynthesis. CO2 + H2O + (sunlight)  (CH2O)n + O2 Organisms consume carbohydrates and convert them into energy through an enzymatic process called respiration. C6H12O6 + 6O2  6CO2 + 6H2O Kcal

27 Respiration Internal:
Factors affecting the respiration rate of FFV: Internal: Type of tissue or organ: Leaves > fruits> roots. Product size: bigger size< respiration rate. Stages of development: young leaves >respiration. In fruits will depend on their classification as climacteric or non-climacteric. Presentation 3.2

28 Respiration Presentation 3.2

29 Perishability rate. PERISHABILITY INDEX Very high High Moderate Low
Very low POTENTIAL LIFE (WEEKS) < 2 weeks 2 - 4 weeks 4 - 8 weeks weeks > 16 weeks PRODUCTS broccoli, cauliflower, blackberry, strawberry avocado, pineapple, celery, tomato lemon, watermelon mango, potato, onion, apple, garlic, pear nuts, dried fruits.

30 Respiration External:
Factors affecting the respiration rates: External: mechanical damage and product’s sanitary condition. temperature. atmosphere composition (< Oxygen and CO2< respiration; > ethylene > respiration). physical barriers (waxes, plastic films, etc.) Presentation 3.2

31 Presentation 3.2

32 Presentation 3.2

33 Temperature effects on
respiration rate. At temperatures above the optimum, the rate of deterioration increases 2 to 3 fold for every 10ºC rise in temperature. High temperature-increases the transpiration rate. 30ºC 20ºC Respiratory rhythm 10ºC Time

34 Transpiration Loss of water, as vapor, from the product’s area exposed to the air, throughout the cuticle, lenticels, stomas, etc. It depends on: Internal factors: species and variety. type of tissue. Presentation 3.2

35 Transpiration Temperature (> temperature> transpiration)
External factors: Relative Humidity (<RH> transpiration). Temperature (> temperature> transpiration) Altitude (higher altitude< transpiration). Presentation 3.2

36 reducing transpiration rates Relative humidity management.
Is the moisture content (as water vapor) of the atmosphere, expressed as a percentage of the amount of moisture that can be retained by the atmosphere at a given temperature RH can influence water loss, decay development, incidence of physiological disorders, and uniformity of fruit ripening. Presentation 3.2

37 reducing transpiration rates
Curing. Waxes and others surface coatings . Polymeric films for packing. Avoiding physical injuries. Adding water to those commodities that tolerate misting with water. Presentation 3.2

38 waxing fruits Wax layer restricts the gases interchange.
Air in the internal Cavity

39 reducing transpiration rates Wetting floors in storage rooms.
Adding crushed ice in shipping containers Presentation 3.2

40 Ripening Process Post-harvest technology: to delay
Physiological process that occur at the cellular level. After finishing the anabolic process, a series of catalytic reactions start –degradation of: chlorophyll, aromas, organelles and finally causing cellular collapse/death. Post-harvest technology: to delay as long as possible, the tissue disintegration/senescence phase Presentation 3.2

41 Ripening Of Fleshy Fruits
Last part of the fruit development process Ripening Period Cell Expansion Period Fruit Fresh Weight Maturity (Full sized fruit) Cell Division Period Pollination/ Fertilization Time

42 Ecological Function of Fruit Ripening
Ripening must happen when the seeds are mature In order for ripening and seed maturity to happen together, the plant must control the process

43 So What Is Ripening? Increase in “sweetness” due to conversion of starch sugars Softening due to a breakdown of cell walls Less “tartness” due to decrease in acidity Increase in flavor compounds Color change Changes in respiration due to all

44 Starch to Sugar Conversion
Banana Sugar % Starch Days

45 Softening of Fruit % content of soluble pectin Soluble pectin
Fruit Firmness, kg pressure Firmness Days in storage

46 Pectin Substances-Plant Gums
Plant cell wall showing Pectin

47 Pectin Substances-Plant Gums

48 Pectin Substances-Plant Gums
Role of Pectin in Plant Tissue (fruits) In outer cell walls, closely associated with cellulose – precursor of pectin: Protopectin Absorb water and transfer it among cells Responsible for firmness, texture (fruits & veggies) Softening during ripening Breakdown of colloidal stability in fruit juices

49 Pectin Substances-Plant Gums
Change in pectin substances during ripening Protopectin in middle lamella between cell walls soluble pectin Reduce cell wall thickness Softening & Ripening Decrease the degree of esterification of carboxyl groups with methyl alcohol

50 Pectin Substances-Plant Gums
Pectin is a polymer of α-Galacturonic acid with a variable number of methyl ester groups. Methylated ester of Polygalacturonic acid Chains of 300 to 1000 glalacturonic acid units Joined with 1α→4 linkages This structure shown here is three methyl ester forms (-COOCH3) for every two carboxyl groups (-COOH) hence it is has a 60% degree of esterification, normally called a DE-60 pectin

51 What is Control Mechanism?
That insures: “ripening and seed maturity happen together”

52 Controlling Ripening The mechanism plants use is a gas:
Ethylene: C2H4 produced in response to seed maturation (less auxin???) How does ethylene control ripening? Stimulates production of enzymes that Convert starch to sugar Break down cell walls Break down acids

53 Ripening Of Fleshy Fruits
Cell Expansion Period Ripening Period Increasing Fruit Fresh Weight, Respiration Level, Gas Production Etc. Ethylene Respiration Cell Division Period Flavor components Pollination/ Fertilization Optimum eating stage Optimum storage stage

54 STRAWBERRY –EXTERNAL COLOUR CHANGES.

55 Fruit ripening Loss of chlorophyll (undesirable in veg.)
Production of carotenoids and antocianines. Starches conversion into sugars. Changes in organic acids, proteins and fats. Reduction in tannins and fungistatic compounds.

56 MANGO-INTERNAL COLOUR CHANGES

57 Avoid the negative effect of external factors
To reduce and delay the action of the internal factors that are responsible for product deterioration Avoid the negative effect of external factors Post-harvest Quality maintenance Presentation 3.2

58 Preservation Methods:
Refrigeration/chilling : some fresh produces can rapidly deteriorate under unrefrigeration, which affect the EP cost to be greater. Some precuts and convenience fresh produces such as salad greens should be delivered at temperature of approximately 34 ̊ F to 36 ̊ F.

59 Waxing: The wax prevents moisture loss and also contributes to the appearance of the produce. Some items likely to be waxed are apples, avocados, bell peppers, cantaloupes, cucumbers, eggplant, grapefruit, lemons, limes, melons, oranges, parsnips, passion fruit, tomatoes, and etc. Presentation 3.2

60 Controlled-atmosphere storage: This room is sealed and oxygen is removed, then variety of other gases are introduced in order to retarding spoilage and reducing the rate of respiration, but the produce that will rapidly deteriorate after removed from the controlled room. Chemically treated produce: The produce will have a longer shell life.

61 What is chilling? A unit operation in which temperature of a food is reduced between -1 and 8 C.

62 Effect of temperature Biochemical changes caused by micro-organisms and naturally occurring enzymes increase with temperature. Therefore, by reducing temperature we reduce the biochemical changes.

63 Why we chill foods? Enhances Shelf life
To reduce the rate of biochemical activity (respiratory rate of foods) To reduce the rate of microbial activity To preserve sensory and nutritional value of foods Consumers consider chilled foods, because easy to prepare, high quality, healthy natural and fresh

64 Refrigeration Temperature control.
Product protection from sun heat (full sunlight) after harvesting. Pre-cooling treatments to remove field heat. Refrigeration. Maintaining the cold chain. Presentation 3.2

65 Key factor affecting product deterioration rate.
Temperature Key factor affecting product deterioration rate. is the most effective tool for extending the shelf life of fresh horticultural commodities. Key effect on spores germination and pathogenic growth. Presentation 3.2

66 Temperature Presentation 3.2

67 TºC Temperatures above or below the optimal range, can cause product
deterioration due to: Chilling injury. Freezing injury. Heat injury. TºC Presentation 3.2

68 Chilling Injury Temperature
Chilling injury causes undesirable physiological changes (external or internal browning, skin blemishes, failure to ripen) Fruits and vegetables undergoing chilling injury should be stored above a certain temperature Chilling injury results from imbalance of metabolic activity There is an overproduction of some toxic metabolites Presentation 3.2

69 Examples of foods undergoing chilling injury
Apples (<2-3 C) Bananas (< C) Lemons (< 14 C) Mangoes (<10-13 C) Melons, pineapples, tomatoes (< 7-10 C)

70 Chilling injury. Presentation 3.2

71 Heat of respiration (Watts/tonne)
0 C C C Apples Bananas Oranges Carrots Potatoes Source: Leniger and Beverloo (1975) and Lewis (1990)

72 Temperature Freezing: Freezing produces an immediate collapse of tissues and total loss of cellular integrity. Presentation 3.2

73 Direct sources of heat can rapidly heat
Temperature Heat injury: Direct sources of heat can rapidly heat tissues to above the thermal death point of their cells, leading to localized bleaching or necrosis or general collapse. Presentation 3.2

74 Cooling Objective: to remove the field heat. Movement of the caloric energy from the product to the cooling substance. Presentation 3.2

75 waxing fruits Wax layer restricts the gases interchange.
Air in the internal Cavity 75

76 manipulation of the environment
around the produce Environment Modified and controlled atmosphere storage Presentation 3.2

77 Controlled Atmosphere (CA)
Environment Controlled Atmosphere (CA) Apples, as any living entities..breath 21% Oxigene 0.35% CO2 Cold room 0ºC 2% O2 1% CO2 Filters

78 Manipulation of the environment
around the produce Presentation 3.2

79 Environment Modified atmosphere (MAP) 21% O2 0.035% CO2
Modify the concentration of gases in the produce packing. Reduce respiration rate. Reduce ethylene action. Delay ripening & senescence. Increase product’s shelf life. O2 CO2 O2 CO2

80 Environment Modified atmospheres
Use of MAP during packing is highly increasing. Usually designed to maintain 2% - 5% of O2 and 8% - 12% of CO2, extend shelf life of fresh-cut fruits and vegetables. Presentation 3.2

81 MODIFIED ATMOSPHERE PACKAGING (MAP)

82 C6H12O6 + O2 ------- CO2 +H20+ Energi (ATP) PANAS
Respirasi C6H12O6 + O  CO2 +H20+ Energi (ATP) PANAS CO2 Energy ATP O2 H2O

83 DEFINITION Modified atmosphere is a condition of atmosphere (normally in a package of commodity) around the commodity that is different from that of air (78.08% N2, 20.95% O2, and 0.03% CO2). Usually this involves reduction of O2 and/or elevation of CO2 concentrations. Modified atmosphere packaging (MAP) involves the exposure of produce to the atmosphere generated in a package by the interaction of produce, the package and the external atmosphere. Different additives that may affect the atmosphere may be introduced into the package before it is sealed. The main feature distinguishing MAP from controlled atmosphere (CA) is that , in the case of MAP, active human involvement stops at the moment of sealing. Wide spectrum of techniques of MAP from Individual sealed packaging to the more intricate control of microorganisms in the new package of salad bar items. MAP is a multidisciplinary technology of maintaining freshness that utilises basic principles of chemistry, physics, plant physiology and pathology, microbiology, food science, engineering, polymer chemistry.

84 The MAP System Plastic Film Area Volume Permeability O2
Permeability CO2 thcikness CO2i CO2e O2i Produce Weight Oxygen uptake CO2 Production O2e

85 MAP should be considered as a supplement to proper temperature and relative humidity management

86 PRINCIPLES OF MAP MAP is a dynamic system during which respiration and permeation occur simultaneously. Factor affecting both respiration and permeation must be considered when designing a package. Commodity mass, temperature, O2, CO2, and C2H4 partial pressure and stage of maturity are known to influence respiration in a package. Type, thickness, intended holes, and surface area of packaging film, as well as temperature, RH, and gradient of O2 and CO2 partial pressures across the film, are known determinant of permeation. Package equilibrium or steady state is defined as the point at which the commodity CO2 production and O2 consumption rates are equal to the permeation rates of the respective gases through a package at a given temperature. Poorly designed package will become anaerobic or develop unacceptable levels of CO2 before equilibrium is achieved.

87 MAP for fruits and vegetables
Various films have been used for packaging F&V to minimize respiratory anaerobiosis and potential microbiological hazards In China and Japan sealed-packaging has become a common new technique for citrus fruit storage. Sealed-package of many F&V are commonly available on the shelves of supermarket. One of the novel approaches in MAP of F&V is the introduction of a gas mixture of desirable composition into a package before sealing.

88

89

90 Presentation 3.2

91 Commercial use CA is used for transporting and storage of apples, pears, less used in kiwifruits, avocados, nuts, dry fruits and persimmon. MA- for long distance transport is used in mangoes, apples, bananas, avocados, plums ,strawberries, blackberries, peaches, figs, nectarines. Presentation 3.2

92 Food Preservation So, how does food preservation work?
All of the food preservation processes work by slowing down the activity and growth of disease causing bacteria, or by killing the bacteria all together. They also slow down or stop the action of enzymes which can degrade the quality of the food. Temperature Water Activity pH Water Activity aw is a term used to describe the relative availability of water in a substance.

93 Food Preservation Food preservation is the process of treating and handling food in such a way as to stop or greatly slow down spoilage to prevent foodborne illness and extend its shelf-life. Food processing methods that are used to preserve foods include: Refrigeration and freezing Canning Irradiation Dehydration Freeze-drying Pickling Pasteurizing Fermentation

94 Cold storage Chilling Freezing slowing microbical growth
reduce enzymatic and chemical reactions slow postharvest metabolism reduce moisture loss Freezing slowing microbial and chemical reactions water immobilization reducing molecular mobility some microbial destruction

95 Control of redox potential
CA/MAP prevent postharvest ripening reduce microbial activity

96 Reducing aw drying freeze-drying humectants freezing
slowing microbial and chemical reactions water immobilization reducing molecular mobility

97 Fermentation inhibition of spoilage/pathogenic flora by beneficial microbial flora consumption of substrate for biochemical/chemical reactions production of antimicrobials acidification

98 Preservatives acidification other preservatives pH change
antimicrobial property other preservatives antimicrobial antioxidant enzyme inhibitor control redox potential

99 Chilling texture degradation in vegetables
cold shortening of muscle foods, staling of bread

100 Freezing small many crystals desired, fast freezing entrapment of solutes, less than max concentration in the unfrozen phase large crystals, slow freezing max concentration of solutes, tissue damage, partial dehydration, local freeze concentration freezer burn, sublimation of ice, dry brown spots on poultry, beef antimicrobial effect due to concentration, intracellular freezing destabilization of proteins, vitamin and pigment degradation, oxidation of lipids

101 Concentration and dehydration
concentration > 20% moisture dehydration < 20% moisture evaporation, crystallization, sublimation, membrane separations microorganisms survive, can recover, grow depending on aw

102 Modified atmosphere closed storage rooms, allow respiratory activity
in packaging, remove air, replace with other gases, N2, CO2 vacuum packaging vacuum, nitrogen: cheese, meat CO2 : fruits and vegetables, meat

103 Packaging glass, metal, plastics, paper
transport of gases, water vapor, low MW components resistance (mechanical, heat, chemical) oxygen, carbon dioxide, moisture permeability light transmission inertness

104 Aseptic packaging 1. product sterilization 2. package sterilization
3. Aseptic filling and sealing Longer shelf life, better quality (?)

105 Hurdle technology developed for limiting the growth of microorganisms in nonsterile foods (Leistner, 1978) combined effects of preservation methods > sum of effects individually or large amounts of a single factor

106 Hurdle technology has been used unintentionally pickles
pH + preservative (acid) + salt sausage aw + smoke + salt + spices + preservatives IMF (dried fruit, soft cookies) aw + heating + preservatives pastırma salt + spices + aw

107 Thank you

108 Preharvest factors affecting the quality
of fresh fruits and vegetables. Climatic conditions: Temperature and light intensity can influence the content of ascorbic acid, carotenes, riboflavin, thiamine and flavonoids. Rainfall affects the water supply and the susceptibility of plant organs to mechanical damage and decay. Presentation 3.2

109 Causes....factors favoring quality decay.
Primary damages are the result of inappropriate technologies and handling during the post-harvest chain: • inappropriate Infrastructure for produce packaging and storage. • improper transport conditions. • lack of planning (i.e.. harvesting). • delays, improper conditions during distribution and marketing. Presentation 3.2

110 Causes....factors favoring quality decay.
during periods of oversupply-poor handling increase. poor or inappropriate harvesting techniques. poor produce handling. damages originated during handling and transport. delays during the distribution process. loses of weight and water. Presentation 3.2

111 cleaning and disinfection
Post-harvest procedures Harvesting Selection, cleaning and disinfection Reception Pre-cooling Other treatments Grading Drying Storage Transport Packing and packaging Presentation 3.2

112 Harvesting Associated hazards
inappropriate maturity at harvest (over ripening increases sensitivity to quality decay ; immature fruits market rejection). inappropriate harvest technique (mechanical damages-physical injuries). climatic conditions at harvesting (free water, exposition of product to direct sun light ) harvesting wet products (increase sensitivity to quality decay) inappropriate harvesting recipes/containers ( physical injuries). Presentation 3.2

113 Recommendations training personnel on optimum maturity indices. Application of appropriate maturity indices based on: external quality color, consistence, phenological stage, etc. Harvesting time: early in the morning or late in the afternoon in order to minimize the sun effect. Optimizing harvesting recipes/containers (size, materials, height, number of produce layers, conditions, etc. ) protection of product of direct sun intensity. Presentation 3.2

114 Produce reception Associated hazards
uncovered areas (direct exposition of products to sun light and adverse climatic conditions) inappropriate handling of the product during loading and unloading. inappropriate product heaping (mechanical damages). delays in the operations (if conditions are inappropriate they can generate increasing product temperature and quality decay) lack of planning during harvesting (increase delays in the operations). no methods applied to remove field heat or use of inappropriate ones. Presentation 3.2

115 Presentation 3.2

116 Possible Hazards associated
Pre-cooling Possible Hazards associated Definir actores/roles/ Expectativas. If the methods of pre-cooling are inappropriate, they can: produce dehydration of the product (i.e.. high speed of cooling air) tissue damage –i.e. as result of inappropriate packing -product contact with ice. produce quality decay caused by sensitivity of the product to water exposition. accelerate quality decay by accumulation of water in some areas of the product (between leaves and calyx) Presentation 3.2

117 Cleaning and disinfection
Definir actores/roles/ Expectativas. Cleaning and disinfection Objective: Removing impurities from the product. Definir actores/roles/ Expectativas. Washing methods: Web methods: Immersion (product floating). Spraying . Dried methods: Brushing. Inhalation/aspirate. Presentation 3.2

118 Cleaning and disinfection
Definir actores/roles/ Expectativas. Cleaning and disinfection Possible Hazards associated Definir actores/roles/ Expectativas. product water sensitivity. poor water quality. mechanical damage (inappropriate conditions of brushes, etc). water accumulation in the product can cause product quality decay. Presentation 3.2

119 Grading methods: by size, weight, color, etc.
Associated Hazards Mechanical damages by vibration, impact/hitting, compression, etc. caused either by poor handling or inappropriate equipment maintenance and design. Grading methods: by size, weight, color, etc. Presentation 3.2

120

121 Over packing (many product layers).
Packing and packaging Associated Hazards Definir actores/roles/ Expectativas. poor packing design (reduces efficiency and increases the risk of mechanical and biological hazards). improper packing (lack of ventilation, low material resistance, sharp and wrinkled surfaces, etc.). Over packing (many product layers). Presentation 3.2

122 Inappropriate pile up during packing.
Packing and packaging Associated Hazards Definir actores/roles/ Expectativas. Inappropriate pile up during packing. packing products with different degree of maturity. mechanical damages caused by personnel or improper design of mechanical grading machines. Problems regarding over-handling of products and inappropriate process flows during post-harvest handling. Presentation 3.2

123 Associated Hazards: mechanical, physical, biological damages.
Storage Associated Hazards: mechanical, physical, biological damages. Inappropriate design of cooling rooms. Poor or lack of equipment maintenance and cleaning programmes. Lack of control of temperature and Relative Humidity conditions. Lack of control on personnel entrance to the cooling rooms. Poor or lack of cooling rooms cleaning programmes. Inappropriate distribution/location of the product inside the cooling room (reducing air circulation). Presentation 3.2

124 Associated hazards: chemical, biological, mechanical damages.
Transport Associated hazards: chemical, biological, mechanical damages. Bad conditions of the vehicles tents/covers. Poor cushioning systems of the vehicles. Inappropriate systems of loading and unloading. Uncovered vehicles, expose the product to the negative effect of the environmental conditions. poor control of temperature and relative humidity in the refrigerated transport systems. Inappropriate systems of packing (p.e. in bulk). Presentation 3.2

125 INNOVATIONS IN THE TRANSPORT
Definir actores/roles/ Expectativas. INNOVATIONS IN THE TRANSPORT Presentation 3.2

126 Loading and unloading systems efficiency
Definir actores/roles/ Expectativas. Loading and unloading systems efficiency Presentation 3.2

127 Other Post-harvest treatments
Definir actores/roles/ Expectativas. Associated hazards: increase product’s susceptibility to biological, mechanical damages and quality decay. Improper handling during treatment application. Inappropriate application of the treatments (p.e. temperatures above or below the optimum recommended). Improper RH conditions. Poor equipment maintenance and cleaning. Doses above the recommended ones (i.e.. irradiation dosages). Presentation 3.2

128 Cold chain harvesting To protect the product from direct sun light.
Quick transport to the packaging. harvesting Pre-cooling Minimize delays before pre-cooling. Uniform product’s cooling. Store the product at optimum temperature conditions . Practice first in first out rotation. Ship to market as soon as possible. Temporal storage Use refrigerated loading area. Cool truck before loading. Load pallets towards the center of the truck. Avoid delays during transport. Monitor product temperature during transport. Transport Presentation 3.2

129 Final Considerations There is not a direct relation between a given post-harvest technology efficiency and its cost. Expensive equipment does not always imply high efficiency, and even the best equipment, without proper management may have little utility and poor results. Effective training and supervision of personnel must be an integral part of quality and safety assurance programs. Presentation 3.2

130 Final Considerations Proper harvesting time, avoid direct sun light,
Proper product handling during the post-harvest Chain relies in understanding the factors that affect the quality and safety of the product, and the different mechanisms to minimize their impact. Simple handling practices can have important impact on product quality and safety maintenance. Proper harvesting time, avoid direct sun light, proper handling, proper ventilation, etc. Presentation 3.2


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