1. Pasteurisation: This requires raising the temperature of the juices to 80 – 95degC for 1-10 minutes prior to filling hot. At the simplest level, this may be carried out in a stainless steel, enamelled or aluminium saucepan over a gas flame, but this can result in localised overheating at the base of the pan, with consequent flavour changes. To avoid the use of large expensive, stainless steel pans, a large aluminium pan can be used to boil sugar syrup. A given amount of the syrup is then mixed with fruit juice in a small stainless steel pan and this increases the temperature to 60 – 70degC. The juice/syrup mixture is then quickly heated to pasteurising temperature.
2. Preservation under CO2 pressure may be done at a concentration of 1.5% CO2 under a pressure of 7 kg/cm2. At the distribution step, proceed at CO2decompression and the juice is then submitted to a sterilising filtration and aseptic filling in receptacles.
3. Preservation by freezing is carried out at about -30deg C, after a preliminary de-aeration; storage is at -15 to -20deg C.
Filling, Bottling and Packaging
Juices can be packaged in many different ways. Bottles, glass and plastic, tetra packs of different shapes and sizes, plastic pouches and even cups can be used. All packaging must ensure no leakages.
Filling and bottling
In all cases, the products should be hot-filled. A stainless steel bucket, drilled to accept a small outlet tap, has proved to be a very successful filler. Output can be doubled quite simply by fitting a second tap on the other side of the bucket. This system can be used to produce 500-600 bottles of fruit juice per day. After filling hot, the bottles are capped and laid on their sides to cool prior to
labelling.
Note: Care is needed when producing pineapple juice due to a heat resistant enzyme in the juice. The enzyme damages skin after prolonged contact and workers should therefore wear gloves to protect their hands. The juice must be heated to a higher temperature for a longer time to destroy the enzyme (eg boiling for 20 minutes).
Packaging
Small scale production packaging can be done cost effectively with plastic bottles, plastic bags that need sealing, and cups that need sealing. For cups using the foil heat sealed lids is adequate and can be done cost effectively to begin with by using a hot iron before upgrading to a more commercial hand sealer.
Quality control
As in all food processing enterprises it is necessary to ensure that the fruit products are correctly formulated and priced to meet the customer’s requirements, and that production costs are minimised to ensure that a profit is made. The quality of each day’s production should be monitored and controlled to ensure that every bottle of juice has the correct keeping and drinking qualities. In particular the following points should be observed:
- Pay particular attention to the quality of re-usable bottles, check for cracks, chips etc and wash thoroughly before using. If bottles are not able to be sterilized with hot water as in the case of plastic bottles, they can be sterilised in cold water using the sterilising agent Calcium Hypochlorite.
- The concentration of preservative should be carefully controlled for correct preservation of squashes and cordials, and may be subject to local laws. Check first and use accurate scales to measure the preservative.
- The temperature and time of heating are critical for achieving both the correct shelf life of the drink and retaining a good colour and flavour. A thermometer and clock are therefore needed.
- Standardisation of products is a must therefore the correct weight should be filled into the bottles each time
Information carried on packaged juices must include all statutory requirements including the following:
1. Product Name
2. Company name and address
3. Manufacture and Expiry dates
4.Ingredients
5. Weight of product
6. Nutritional analysis
7. Kebs Standardisation Mark
8. Batch Number
9. Barcodes (for main stream markets only)
10. Storage Information
11. Usage Information
12. Preservatives
This information can be carried on independent stickers to be attached to the packaging or can be printed directly onto the packaging.
Shrink wrapping
Shrink wrapping is used to ensure security on lids of products as well as for labelling. Heat in the form of hot air or hot water is used to shrink a plastic film around the top of bottles or entire bottles when used for labelling. The end products look very professional. The advantages of labelling this way allow one to purchase generic empty packaging as in bottle or cups and then label in batches as needed rather than going through the process and cost of labelling minimum volumes of printed packaging which can be prohibitively expensive for the small scale and start up produce.
To shrink wrap, simply blow hot air using a device as simple as a hair drier or commercial blow drier onto the shrink wrap plastic held over the surface of the product to be covered. The plastic will shrink when it comes into contact with the heat and securely cover the mould over which it is being placed. Alternatively dip the entire product with the shrink wrap sheath into hot water for a few seconds, remove and dry.