Fresh Whole Prepared Fruit and Vegetable Products

Food items: Alfalfa sprouts, Apples, Apricots, Artichoke, Asparagus, Aubergine, Avocado, Bananas, Bean sprouts, Beetroot, Blackberries, Broad beans, Broccoli, Brussels sprouts, Cabbages, Cauliflower, Carrots, Celery, Cherries, Chicory, Courgettes, Cranberries, Cucumber, Cumquats, Fennel, Garlic, Gooseberries, Grapefruit, Grapes, Green berries, Guava, Kale, Kiwi fruit, Leek, Lemons, Lettuces, Limes, Lychees, Mandarins, Mango, Mangosteen, Marrow, Melon, Mixed fruit salads, Mixed vegetable salads, Mulberries, Nectarines, Onions, Oranges, Papayas, Parsnips, Passion-fruit, Peaches, Peas, Peppers, Pineapple, Plums, Potatoes, Prickly pear, Radish, Rambutans, Raspberries, Rhubarb, Rocket, Shallot, Spinach, Star apples, Strawberries, Sweetcorn, Swede, Tomatoes, Turnip, Water chestnuts, Water cress, Watermelon, Yams, other items

Recommended gas mixture
5% O₂
5% CO₂
90% N₂

The gases and mixtures listed above are for general guidance. To identify the optimum gas for your product and process, we recommend you undertake a product trial with the help of an Air Products MAP gas specialist. 

Storage temperature
• Legal maximum*: 8° C
• Recommended: 0° C to +3° C

Achievable shelf-life
• In air: 2-7 days
• In MAP: 5-35 days

Principle spoilage organisms and mechanics
Pseudomonas species (in air), Lactic acid bacteria, Erwinia species, Enterobacteriaceae, yeasts and moulds, Enzymic browning, moisture loss

Food poisoning hazards include
Clostridium species, Salmonella species, Staphylococcus aureus, Listeria monocytogenes, Bacillus species, E.coli and E.coli 0157.

Typical MAP machines
Retail
•  TFFS – Thermoform-fill-seal
•  PTLF – Preformed tray and lidding film 
•  HFFS – Horizontal form-fill-seal
•  VFFS – Vertical form-fill-seal

Typical types of package
Retail: Tray and lidding film, Tray inside pillow pack, pillow pack

Examples of typical MAP materials
Tray:
• UPVC/PE
• HDPE

Lidding and/or pillow pack film:
• OPP
• OPP/PE
• EVA
• MP
• MPOR

The principal spoilage mechanisms affecting whole and prepared fresh fruit and vegetable products are microbial growth, enzymic browning, and moisture loss.

MAP which results in depleted O₂ and/or enriched CO₂ levels is very effective at inhibiting these spoilage mechanisms, as well as:
• reducing respiration
• delaying ripening
• decreasing ethylene production and sensitivity
• retarding textural softening
• reducing chlorophyll degradation
• alleviating physiological disorders

Unlike other chilled perishable foods that are MA packed, fresh fruit and vegetables continue to respire after harvesting and any subsequent packaging must take this into account. The products of aerobic respiration are CO₂ and water vapour (whereas fermentation products such as ethanol, acetaldehyde and organic acids are produced during anaerobic respiration). Respiration is affected by numerous intrinsic properties of fresh produce as well as various extrinsic factors but, generally speaking, the Achievable shelf-life of MA packed produce is inversely proportional to respiration rate. The depletion of O₂ and enrichment of CO₂ are natural consequences of the process of respiration when fresh fruit or vegetables are stored in an hermetically-sealed package. Such modification of the atmospheric composition results in a decrease in the respiration rate of plant material. If produce is sealed in an impermeable film, inpack O₂ levels will fall to very low concentrations where anaerobic respiration will be initiated. Anaerobiosis is usually associated with undesirable odours and flavours and a marked deterioration in product quality.