Nutritional significance
Processing
Packaging
Suitability for small-scale production
A wide range of plant materials are used to manufacture beverages. These include leaves, stems, sap, fruits, tubers, and seeds (grains).
The large number of beverages may be classified as shown:
The market for beverages is broadly divided in many countries into those products that are bought to quench thirst, and those that are consumed on special occasions including festivals. The former group are mostly nonalcoholic and include tea, coffee, and soft drinks (including juices, nectars, and carbonated drinks). In some countries these products are also used on social occasions, whereas in other areas alcoholic beverages are preferred (although soft drinks are also usually available). In most countries, the market for alcoholic and non-alcoholic drinks is specific with regard to religious and cultural taboos.
Competition from medium/large-scale producers is most acute for small-scale producers in beverage manufacture. Many large-scale producers promote their products by implying status in their consumption and spend considerable amounts on advertising and packaging. They may also have established sophisticated distribution systems and specific agreements with wholesalers and retailers. Thus beverage manufacture is one of the most difficult for small-scale producers to establish and succeed in.
Most beverages contain a great deal of water. This does not add many nutrients to the diet, but it does play an important role in maintaining body balance by preventing dehydration.
Beverages are not usually consumed for their food value, but many, particularly the fruit drinks, contain quite a high percentage of sugar and therefore add to the energy content of the diet. Additionally fruit juices provide a supply of vitamins and minerals.
Certain drinks contain artificial flavourings and colourings. The use of such additives is governed by legal requirements and it is vital to keep to these regulations in order to protect the consumer from any undesirable side-effects. Some colouring agents for example are thought to cause hyperactivity in children, and are therefore to be avoided.
Alcoholic drinks are judged in terms of flavour and the stimulant effect they produce. In many countries alcohol production is strictly controlled by government agencies and it may be difficult to obtain the necessary permits to produce these beverages legally.
Non-alcoholic beverages
A wide range of drinks can be manufactured which contain as the base material either pulped fruit or juice. Many are drunk as a pure fruit juice without the addition of other ingredients, whereas others are diluted with sugar syrup.
For simplicity, fruit drinks can be divided into two groups:
· Those that are drunk immediately after opening.
· Those that are used little by little from bottles which are stored between use.
The former group should not need any preservative if processed and packaged properly. However the latter must contain a certain amount of permitted preservatives to have a long shelf-life after opening.
The following list may prove helpful in distinguishing between the different types of drink:
Juices. These are pure fruit juice with nothing added.Nectars. These normally contain 30 per cent fruit solids and are drunk immediately after opening.
Squashes. These normally contain at least 25 per cent fruit pulp mixed with sugar syrup. They are diluted, to taste, with water and may contain preservatives.
Cordials. These are crystal-clear squashes.
Syrups. These are concentrated juices which are clear. They normally have a high sugar content.
Each of the above products is preserved by its natural acidity and by pasteurization. Some drinks (syrups and squashes) also contain a high concentration of sugar which helps to preserve them.
Alcoholic drinks
The most common examples of alcoholic beverages are wines and beers. Beer is usually made from a cereal, whereas wine can be produced from either cereals or fruit. Both can be distilled to produce spirits with an alcohol content of 30-50 per cent.
Both wines and beers are produced by fermentation which involves the conversion of sugars in the raw material or added sugar into alcohol and carbon dioxide. Different varieties of the yeast Saccharomyces cerevisiae are used to produce wines or beer. A simplified list of the differences is shown in the table opposite:
Product |
Type of yeast |
Beer |
'Top yeast' - Saccharomyces cerevisiae |
Lager |
'Bottom yeast' - Saccharomyces carlsbergensis |
Fruit wine |
'Wine yeast' - S. oriformis, S. chevalieri, |
Palm wine |
'Wild yeast'- natural mixture of yeasts |
Rice wine |
Saccharomyces sake |
Although it is possible to use any strain of brewer's yeast for fermentation, it is necessary for a small producer to select one that works well and then continue to use it to produce a consistent product.
Alcohol has a lower boiling-point than water and distillation (vaporizing the alcohol and then condensing it) is used to concentrate the alcohol in spirit drinks. Distillation is carried out in stills which can be purchased for production at all levels. Alternatively, it is possible to construct a basic still using locally-available materials (see below).
Traditional still
A well-cleaned oil drum is fitted with a pipe to carry away the vapour, and a safety pipe. Alcoholic liquor is placed inside the drum and heated. On vaporization, the alcohol vapour is carried out of the drum via the pipe and passed through cooled air or cool water. The distillate condenses and is collected.
Distillation is more frequently carried out on a centralized commercial level, although it does occur on a small scale.
Small still
|
Juice extraction/pulping |
Mashing |
Mix |
Heat |
Ferment |
Filter |
Bottle |
Carbonate |
Pasteurize |
Beer |
|
* |
* |
* |
* |
* |
* |
*optional |
* |
Wine |
* |
|
* |
* |
* |
* |
* |
|
|
Sparkling wine |
* |
|
* |
* |
* |
* |
* |
|
|
Fruit juice * |
* |
|
|
|
|
* |
* |
|
* |
Carbonated drink |
|
|
* |
|
|
|
* |
* |
* |
The table above outlines the processing steps for the production of a range of representative beverages.
Equipment required
Processing stage |
Equipment |
Section reference |
Juice pulping/extraction |
Fruit press |
53.1 |
Pulper/juicer |
55.1 and 55.2 |
|
Mashing |
Fermentation bins |
03.1 |
Mixing |
Mixers |
|
Boil |
Boiling pans |
48.1 |
|
48.2 |
|
|
48.3 |
|
Fermentation |
Fermentation bins/jars |
03.1 |
Filter |
Filters and filter presses |
29.1 and 29.2 |
Sieves |
29.3 |
|
Strainers |
29.4 |
|
Carbonation |
Carbonating equipment |
06.0 |
Filling into bottles |
Liquid fillers Funnel |
28.1 |
Pasteurize |
Open boiling pan |
48.1 and 48.2 |
Steam jacketed pan |
48.3 |
|
Pasteurizer |
50.0 |
Pulping/juice extraction
Either the juice or the pulp from fruit is the starting material for the manufacture of soft drinks and wines.
Pulping
Soft fruits, such as papaya, can easily be pulped by hand or by using a pestle and mortar. A wide range of hand-operated pulpers are available, or if electric power is available, multi-purpose kitchen-scale equipment such as blenders can be used. At an industrial level, this process is normally carried out in pulpers which brush the fruit through a sieve and eject the skin and stones. Smaller models of this machine can be manufactured and are commercially available.
Extraction
Juice can be extracted from fruit in several ways.
· With a fruit press, fruit mill or hand pulper/sieve.· By crushing/pulping with a mortar and pestle and then sieving through muslin cloth or plastic sieves.
· By steaming the fruit.
· Citrus fruit juices need to be extracted by reaming (squeezing) the fruit, and once again, comparatively simple equipment is available for this purpose.
Fermentation
As mentioned previously the process for achieving fermentation differs considerably depending upon the product. The following paragraphs describe the basic processes for the production of both beer and wine.
Beer
The process for making beer is often referred to as brewing. Brewing actually consists of three stages - mashing, boiling and fermentation.
Mashing involves the use of hot water (approximately 68°C) to extract the soluble materials from the malted grains. This produces a liquid called wort. The process is carried out in large vessels which may be made of wood or stainless steel.
The wort is then subjected to a process of boiling. In Europe this process involves the addition of hops. Boiling takes place in a similar vessel to the tubs used for mashing except that it is flask-shaped, with the neck being elongated in order to carry away the steam, and to prevent over-boiling.
Prior to inoculation (addition of the yeast), the wort is cooled. This is because if added to the hot wort the yeast would be inactivated. The degree to which the wort is cooled differs according to the type of beer to be produced. For example, fermentation for lager is conducted at 12-15°C using the yeast Saccharomyces carlsbergensis. In other cases, the yeast Saccharomyces cerevisiae is used at a temperature of 20°C. During fermentation, the beer is held in fermentation vats or food-grade plastic fermentation bins. When fermentation is complete, the process of packaging will depend on whether the beer is to be sold in draught form (e.g. in a keg), or if it is to be bottled and corked. If it is to be draught, the beer is not filtered and small amounts of yeast are left in it in order to keep it slightly carbonated. In the case of bottled beer, it is filtered and pasteurized.
Wine
In wine-making, the fruit juice or pulp is mixed with yeast and sugar and held in a fermentation bin. Again this may be made from food-grade plastic. This is left for about ten days during the first fermentation stage. Within 48 hours, fermentation becomes vigorous and there is frothing and foaming. It is important to keep the fermentation vessel closed to prevent bacteria and fungi from infecting the wine. After ten days the fermenting wine is racked. This is done by scooping it up together with the solids using a sterilized mug, cup, or jug, and passing it through a muslin or nylon straining cloth. The cloth should have been sterilized and rinsed beforehand, and placed in a funnel. The wine is transferred into narrow necked fermentation vessels. These may be plugged with wads of cotton wool, or specially-designed vessels fitted with a airlock (known as a demijohn) may be used.
Ideally, fermentation is then continued at a temperature of 18°C. The whole process can take from three weeks to three months. The end of fermentation can be judged when it is seen that there are no more bubbles rising to the surface. At this stage, the wine is filtered, in order to remove the sediment from the wine and then syphoned into narrow-necked or food-grade plastic vessels, and stored for the minimum period in the recipe to allow the wine time to clear and mature before bottling. After this period of maturation, the wine is siphoned off into bottles and sealed with a sterilized cork-stopper or screw cap.
Carbonation
This involves the addition of carbon dioxide into a drink. The most usual way of achieving this is to use a pressurized cylinder or tank which contains a mixture of water and carbon dioxide. In the case of soft drinks, the bottle is filled to a certain level with the flavoured syrup, the bottle is positioned under the cylinder head and carbon dioxide is released. The bottles are capped immediately. Cylinders for holding carbon dioxide are available for both large-scale production and in smaller sizes for use at the household level.
Pasteurization
Liquid products such as drinks may need to be pasteurized if they are to have a shelf-life of more than a few days. Pasteurization involves heating the product to a temperature of 80-90°C and holding it at that temperature for between 0.5 and 5 minutes before filling into clean sterilized bottles. Pasteurization is best carried out over a direct heat in stainless steel pans.
Some products can be pasteurized in their bottles. The filled bottles, with the lids loosely closed, are stood in a large pan of boiling water with the water-level around the shoulder of the bottle.
The time and temperature required for pasteurization will depend on the product and the bottle size.
Beverages have differing needs with regard to storage, but the most pressing need for all beverages is simply that they need to be contained without the possibility of leakage.
The tables below outline some of the other storage requirements and the suitability of different types of container.
|
Light |
Air |
Heat |
Micro-organisms |
Insects |
Fruit juice, cordial etc. |
some |
* |
|
* |
* |
Beer |
* |
* |
* |
* |
* |
Wine |
* |
* |
|
* |
* |
Soft drinks |
|
|
|
* |
* |
|
Glass bottle/jar |
Metal can |
Plastic film/pot/pouch |
Ceramic pot |
Fruit juice cordials etc. |
* |
Lacquered |
* |
* |
Beer |
Coloured |
Lacquered |
* |
* |
Wine |
* |
|
|
* |
Soft drinks |
* |
* |
|
|
Glass bottles are the most popular medium for packaging beverages. However, owing to the expense of new glass, many producers (particularly those operating on a small scale) re-use the bottles. This means that in order to prevent contamination the bottles must be sterilized and cleaned properly. Simple hand-held bottle-brushes can be used to ensure a good standard of cleanliness, and mechanized brush-cleaners are also available.
Most beverages are thin liquids and can be filled quite easily by hand, but this is often too slow for a small business. A simple filler can be made by fitting one or more taps to the base of a bucket (see diagram below).
The bucket should be made from stainless steel for hot acid liquids (e.g. fruit juices) or food-grade plastic for cold filling. Iron and copper should not generally be used in food handling.
The type of closures used depends upon the type of product and its particular use (e.g. for glass bottles does it need to withstand internal pressure from carbonation).
Liquid filler
There is a large range of closures available for glass bottles, but the choice for small-scale producers may often be restricted by what is locally available.
Metal 'crown' caps are commonly used for beers and fruit juices, whereas squashes, carbonated drinks and spirits are more frequently packaged using re-sealable metal screw-caps.
Wine is often sealed with a cork but plastic stoppers are equally effective and cost less.
With technological advances in the field of packaging materials, larger commercial manufacturers are using formed waxed cartons for beverages such as fruit juice. These have become very popular since they are cheaper and more convenient. Unfortunately the cost of the equipment needed to form and seal the cartons is very expensive and is presently out of reach for the small-scale producer.
Cheaper alternatives include plastic or foil laminated pouches. If sealed correctly, they can be a very convenient way of packaging.
Beverages can also be canned, but the cost of aluminium or steel cans is usually prohibitive for small-scale producers. In addition, the correct type of lacquer is required on the inside of the cans, and they are not re-usable.
The manufacture of beverages is one of the most competitive areas in which small businesses can operate. Fruit drinks are the most accessible product (in technological terms) for small producers, but even with these there is strong competition from carbonated soft drinks, and it is necessary to establish that there is a demand for a certain drink before production starts.
Wine production is possible and can be very successful in some regions, provided there are not too many government restrictions on alcohol production. In most countries, beer and spirit production is dominated by large-scale, centralized producers, and it is very difficult for smaller producers to compete with them effectively. In some areas, however, there may be scope for upgrading traditional beers and spirits, by producing a uniform-quality product which is attractively packaged.