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《食品脱水技术》(英文版) 6 Dehydration of Vegetables

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The vegetablecultivars quoted in the following process data are, in the main, those bred in temperate climates, the USA and Western Europe and, in the case of pulses, the Antipodes. However, with the growth of dehydration in thedeveloping countries, with tropicalorsubtrop, theseregions, along with Eastern Europe, Egypt and China, who have had a dehydration industry for many years,
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6 hydration of Vegetables The vegetable cultivars quoted in the following process data are, in the main, those bred in temperate climates, the USA and Western Europe and, in the case of pulses, the Antipodes. However, with the growth of dehydration in the developing countries, with tropicalorsubtropicalclimates, theseregions, along with Eastern Europe, Egypt and China, who have had a dehydration industry for many years, have, through their Horticultural Institutes and Ministries of Agriculture, developed indigenous varieties which have been processed with considerable success It may not be possible to identify all these varieties but in the author experience, great assistance has been afforded by the field officers working with these Horticultural Institutes in setting up field and seed trials for the benefit of processors, and they are becoming increasingly knowledgeable in the characteristics required in vegetables for processing uiredy have afforded, also, valuable in formation on the infrastructure required for setting up a processing plant, along with the disposition of labour, local building requirements for food factories and the pattern of irrigation practice e processes set out assume an intermediate size operation with a reasonable measure of automation but, of course, in each case the throughput may be cut down to meet capital budgeting requirements, and whilst most of the preparation plant is geared to a raw throughput of some 1.5 to 3 tonnes per hour of prepared material or 300 to 350 tonnes of raw produce per week, adjustments can obviously be made, introducing more hand labour

6 Dehydration of Vege ta b I es The vegetable cultivars quoted in the following process data are, in the main, those bred in temperate climates, the USA and Western Europe and, in the case of pulses, the Antipodes. However, with the growth of dehydration in the developing countries, with tropical or subtropicalclimates, these regions, along with Eastern Europe, Egypt and China, who have had a dehydration industry for many years, have, through their Horticultural Institutes and Ministries of Agriculture, developed indigenous varieties which have been processed with considerable success. It may not be possible to identify all these varieties but in the author’s experience, great assistance has been afforded by the field officers working with these Horticultural Institutes in setting up field and seed trials for the benefit of processors, and they are becoming increasingly knowledgeable in the characteristics required in vegetables for processing. They have afforded, also, valuable information on the infrastructure required for setting up a processing plant, along with the disposition of labour, local building requirements for food factories and the pattern of irrigation practices. The processes set out assume an intermediate size operation with a reasonable measure of automation but, of course, in each case the throughput may be cut down to meet capital budgeting requirements, and whilst most of the preparation plant is geared to a raw throughput of some 1.5 to 3 tonnes per hour of prepared material or 300 to 350 tonnes of raw produce per week, adjustments can obviously be made, introducing more hand labour in 121

preparation and using Stove or Through-Flow Tray Dryers instead of a Conveyor Band Dryer, either single or multi-pass Whilst a product-mix should be arrived at to give the maximum numberof days workin a season, it is wise toconcentrate on those vegetables which are available for several months of the year, either from seasonal sowings, or by having storage facilities at the factory or farm. Too many change-overs from product to product are costly, often entailing moving plantaround, but what is moreimportant is knowing the market demand for those vegetables for which the climate and growing conditions are ideal HORTICULTURE It is difficult to guide the processor in horticultural procedures, as climate and soil conditions will vary considerably from region to region. The company agronomist must assess all the requirements and problems on the spot, and in a new venture it is absolutely essential to carry out field trials for every vegetable to be processed. However the author has appended some horticultural guide lines for seven of the more popular vegetables grown for dehydration, and these follow the processing data in this chapter he guide lines are based on actual field trials and commercial scale cultivation in several locations varying from temperate to subtropical limatic conditions. In most cases irrigation was available, either contour or GREEN BEANS (1)Flow -Sheet Feed to Line P Cluster Cutting(only for machine harvested beans) tie Snipping Blanching

preparation and using Stove or Through-Flow Tray Dryers instead of a Conveyor Band Dryer, either single or multi-pass. Whilst a product-mix should be arrived at to give the maximum number of days work in a season, it is wise to concentrate on those vegetables which are available for several months of the year, either from seasonal sowings, or by having storage facilities at the factory or farm. Too many change-overs from product to product are costly, often entailing moving plant around, but what is more important is knowing the market demand for those vegetables for which the climate and growing conditions are ideal. HORTICULTURE It is difficult to guide the processor in horticultural procedures, as climate and soil conditions will vary considerably from region to region. The company agronomist must assess all the requirements and problems on the spot, and in a new venture it is absolutely essential to carry out field trials for every vegetable to be processed. However, the author has appended some horticultural guide lines for seven of the more popular vegetables grown for dehydration, and these follow the processing data in this chapter. The guide lines are based on actual field trials and commercial scale cultivation in several locations varying from temperate to subtropical climatic conditions. In most cases irrigation was available, either contour or overhead spray. GREEN BEANS (1) Flow-Sheet Feed to Line I Pneumatic Separator I Washing I Cluster Cutting (only for machine harvested beans) I Inspection I Snipping I Inspec tion I Blanching I22

Sulphating Slicing (long cut Dewatering Drying onditioning reening Inspection (2)Varieties Tendergreen, Processor, Bush Blue Lake (3)Product Handling The bean pods are either harvested by hand or, in the case of large acreages, by mobile bean harvesters. They are fed to the line in a bulk feeder from where the po delivered into a pneumatic separator to remove extraneous matter They are then transferred to a reel washer which, in the case of machine harvested beans, feeds in to cluster cutters, to 'single any beans not separated from their stalks in the harvester. This machine is not necessary for hand harvested beans After inspection on a conveyor belt, the beans are conveyed on a vibratory trough belt and ploughed off into a battery of shippers. The numberof snipers willdepend on throughput, as each machine will handle about 1000kg per hour. At the exit end of each snipper an unshipped bear removal reel takes care of any beans not topped and tailed and returns them to the snippets Snipped beans are then visually inspected on a conveyor belt and delivered into the blancher. This can be either a hot water or steam type, depending on what other products are to be catered for. For example, if cabbage or leaf vegetables are included in the product mix, it would be d visable to opt for steam blanching as this is more suitable for brassicas. Sulphiting is effected by pumping from sulphite make-up pans into the blanching water, in the case of hot water blanching. If steam blanching is

I Sulphiting I Slicing (long cut) I Dewatering I Drying I Conditioning I Screening I Inspection I Packing (2) Varieties (3) Product Handling The bean pods are either harvested by hand or, in the case of large acreages, by mobile bean harvesters. They are fed to the line in a bulk feeder from where the pods are delivered into a pneumatic separator to remove extraneous matter. They are then transferred to a reel washer which, in the case of machine harvested beans, feeds in to cluster cutters, to 'single' any beans not separated from their stalks in the harvester. This machine is not necessary for hand harvested beans. After inspection on a conveyor belt, the beans are conveyed on a vibratory trough belt and ploughed off into a battery of snippers. The number of snippers willdepend on throughput,as each machine will handle about lOOOkg per hour. At the exit end of each snipper an unsnipped bean removal reel takes care of any beans not topped and tailed and returns them to the snippers. Snipped beans are then visually inspected on a conveyor belt and delivered into the blancher. This can be either a hot water or steam type, depending on what other products are to be catered for. For example, if cabbage or leaf vegetables are included in the product mix, it would be advisable to opt for steam blanching as this is more suitable for brassicas. Sulphiting is effected by pumping from sulphite make-up pans into the blanching water, in the case of hot water blanching. If steam blanching is Tendergreen, Processor, Bush Blue Lake I23

used, sulphiting is carried out in a sulphite dip tank situated at the discharge end of the blancher, and the solution of sodium sulphite is made up in the pans alongside. Anhydrous sodium sulphite is always used for green vegetables and sodium metabisulphite forroot vegetables, where sulphiting is permitted under prevailing Food Laws Whole beans are fed on a vibratory conveyor to slicing machines(long cut)with a capacity of 2000kg per hour each, the slicing taking place after blanching to prevent theseed of the pod being washed away in theblanching roces pr After dewatering, the cut beans pass into the dryer, thence to conditioning bins The dried slices are elevated to the screen for sifting to remove broken pieces and fines, and then to the final inspection tables acking should be in poly-lined cartons or drums, rather than paper bags, to avoid breakage Conveyor Band dryer scaled to throughput Temperatures(input): 85/77/60C Conditioning:50·52℃ CRy to6% Overall ratio: 13.1 Drying ratio: 9.1 Cultivation Guidelines for Geen Beans (1)Sowing: oOkg per Ha. Sow in singlerow 7.5-10cm apartat4lcm centres Sow 50mm 2)Fertilisers. On irrigated land use N40/P80/K60 plus 2.5 tonnes of organic per Ha., if 3)Herbicides Preforan or gramoxone or Dachtal (4)Pesticides. Dimethoate or Diazinon; for caterpillar attack, use Folithon or Diazinon 5) Disease Control Botrilex against Southern Blight or Root Rot Afucan or Benlate every 7 days against powdery mildew Kocide, Perenox or Cupravit against bacterial blight or rust (6)Maturity Pick every second day to avoid over-maturity 8mm is the maximum pod diameter (measured across a section of the bean)fo t processIn Harvest is about 60-70 days from sowing Plant population: 430,000 per Ha

used, sulphiting is carried out in a sulphite dip tank situated at the discharge end of the blancher, and the solution of sodium sulphite is made up in the pans alongside. Anhydrous sodium sulphite is always used for green vegetables and sodium metabisulphite for root vegetables, where sulphiting is permitted under prevailing Food Laws. Whole beans are fed on a vibratory conveyor to slicing machines (long cut) with a capacity of 2000kg per hour each, the slicing taking place after blanching to prevent the seed of the pod being washed away in the blanching process. After dewatering, the cut beans pass into the dryer, thence to conditioning bins. The dried slices are elevated to the screen for sifting to remove broken pieces and fines, and then to the final inspection tables. Packing should be in poly-lined cartons or drums, rather than paper bags, to avoid breakage. (4) Drying Conveyor Band dryer scaled to throughput Temperatures (input): 85"/ 77"/ 60°C Conditioning: 5Oo-52"C Dry to 6% Overall ratio: 13.1 Drying ratio: 9.1 Cultivation Guidelines for Geen Beans (1) Sowing: 150kgperHa. Sowinsinglerows7.5-lOcmapartat4lcmcentres. Sow50mm deep in fine tilth. (2) Fertilisers. On irrigated land use N40/P80/K60 plus 2.5 tonnes of organic per Ha., if available. (3) Herbicides. Preforan or Granoxone or Dachtal. (4) Pesticides. Dimethoate or Diazinon; for caterpillar attack, use Folithon or Diazinon. (5) Disease Control. Botrilex against Southern Blight or Root Rot. Afucan or Benlate every 7 days against powdery mildew. Kocide, Perenox or Cupravit against bacterial blight or rust. (6) Maturity Pick every second day to avoid over-maturity. 8mm is the maximum pod diameter (measured across a section of the bean) for processing. Harvest is about 60-70 days from sowing. Plant population: 430,000 per Ha. I 24

BEETROOT (1)Flow-Sheet emi-Continuous Process Feed to Line Destoner-Washer Batch process Autoclave cooking emi-Continuous Pressure Cooking Washing Skin removal Inspection Cutting Dewatering Drying Conditioning Screening Inspection acking Detroit Red Globe (3)Product Handling cut off) at the farm. Care must be taken to avoid bruising and bleedin i Beets should be selected 50-75mm in diameter, with the tops wrung off(n From the bulk feeder they pass through a dry cleaning plant to remove soil, then to a destoner-washer or alternatively a flood washer, if free of stones Two options are open to the processor: (a)to feed the beets into a batch thermoscrew operating at 1. 2atm steam pressure. A Thermoscrew 6m long by Im diameter should batch-cook young beets in a 20-40 minute cycle at a

BEETROOT (1) Flow-Sheet Semi - Continuous Process I Feed to Line a I Autoclave cooking Destoner-Washer Batch Process Semi-Continuous Pressure Cooking Skin Washing Removal 2 I Inspection I Cutting I Dewatering I Drying I Conditioning I Screening I Inspection I Packing (2) Varieties (3) Product Handling Beets should be selected 50-75mm in diameter, with the tops wrung off (not cut off) at the farm. Care must be taken to avoid bruising and 'bleeding'. From the bulk feeder they pass through a dry cleaning plant to remove soil, then to a destoner-washer or alternatively a flood washer, if free of stones. Two options are open to the processor: (a) to feed the beets into a batch thermoscrew operating at 1.2atm steam pressure. A Thermoscrew 6m long by lm diameter should batch-cook young beets in a 20-40 minute cycle at a Detroit Red Globe I25

rate of 1.5-2 tons per hour;(b)the second alternative is to cook the beets in batches in an autoclave, or a series of autoclaves according to quantity of input. Again pressure will require to be at I to 1atm Cooling from the semi continuous cooker will be in a slat washer reel and, if from autoclaves, the cooling water will be applied to the bottom of the autoclave and allowed to circulate until the pressure has dispersed and the autoclave baskets can be removed The cooked beets, when coolenough to handle are fed on toa stainless steel belt where the skins are removed by hand The batch system is the one most often used, as a continuous pressur cooker is a very expensive machine Stainless steel belts should be used when handling beets, as rubber or PVC belts will stain badly and are difficult to clean. The red pigment is betanin, which will leach out if the beets are subjected to washing after peeling and dicing. This should be avoided. Before the beets are transferred to the cutters, any root or fibre remaining should be removed on a second inspection belt, or this can be done by the skinning operators, if the belt is sufficiently long to accommodate both functions It is most important that the beets are fully cooked before cutting and drying. Some processors have attempted to peel beets in a standard steam peeler but the short residence time suitable to soften the skin of vegetables, such as carrots and potatoes, is insufficient to soften the beet to the centre of the root, and partly cooked beets when reconstituted after drying are not acceptable. When the skin is removed, therefore, it is necessary to check that he beetroot flesh is tender to the centre, and it is only by extended cooking under steam pressure, either in autoclaves or a semi automatic steam peeler with a controlled residence time, that the right tenderness can result Peeling and trimming losses will amount to 20-30 percent Beet is usually cut into 9. 5mm dice if used subsequently for pickling No blanching or sulphating is required fter dewatering the dice, they are fed into the dryer (4)Drying. Conveyor Band Dryer scaled to throughput, or Stove dryers Inlet temperatures:99782°/71℃C Condition in bins to5-6%at54°57℃ Raw moisture 89% Overall ratio: 14: 1 to 15: 1 Note s down ratio: 7:1 A K Robins &CoIncof the USA, and also Food Machinery Corporation, make suitable semi automatic beet peeler-cookers The Robins machine is particularly suitable, as the time under steam pressure can be extended as

rate of 1.5-2 tons per hour; (b) the second alternative is to cook the beets in batches in an autoclave, or a series of autoclaves according to quantity of input. Again pressure will require to be at 1 to 1.2atm. Cooling from the semi continuous cooker will be in a slat washer reel and, if from autoclaves, the cooling water will be applied to the bottom of the autoclave and allowed to circulate until the pressure has dispersed and the autoclave baskets can be removed. The cooked beets, when cool enough to handle are fed on to a stainless steel belt where the skins are removed by hand. The batch system is the one most often used, as a continuous pressure cooker is a very expensive machine. Stainless steel belts should be used when handling beets, as rubber or PVC belts will stain badly and are difficult to clean. The red pigment is betanin, which will leach out if the beets are subjected to washing after peeling and dicing. This should be avoided. Before the beets are transferred to the cutters, any root or fibre remaining should be removed on a second inspection belt, or this can be done by the skinning operators, if the belt is sufficiently long to accommodate both functions. It is most important that the beets are fully cooked before cutting and drying. Some processors have attempted to peel beets in a standard steam peeler but the short residence time suitable to soften the skin of vegetables, such as carrots and potatoes, is insufficient to soften the beet to the centre of the root, and partly cooked beets when reconstituted after drying are not acceptable. When the skin is removed, therefore, it is necessary to check that the beetroot flesh is tender to the centre, and it is only by extended cooking under steam pressure, either in autoclaves or a semi automatic steam peeler with a controlled residence time, that the right tenderness can result. Peeling and trimming losses will amount to 20 - 30 percent. Beet is usually cut into 9.5mm dice if used subsequently for pickling. No blanching or sulphiting is required. After dewatering the dice, they are fed into the dryer. (4) Drying. Conveyor Band Dryer scaled to throughput, or Stove dryers. Inlet temperatures: 99"/ 82"/ 71 "C Condition in Bins to 5 - 6% at 54" - 57°C Raw moisture 89% Overall ratio: 14:l to 15:l Drying down ratio: 7:l Note. A.K.Robins &CoIncof theUSA,and alsoFoodMachinery Corporation, make suitable semi automatic beet peeler-cookers. The Robins machine is particularly suitable, as the time under steam pressure can be extended as I26

desired to achieve complete cooking, and it incorporates a second tank where rubber rollers rub off the skin without damage to the flesh Where autoclaves are used these can be the standard canners horizontal type, with front loading. The standard retort crates should not be used, however, as the depth of beets will be too great for the heat to penetrate into the centre of the mass and proper cooking will not take place. Smal stainless baskets with perforated bottoms should be used, of suitable size to fitin layers inside theretortcrates but spacer battens should beused between each row of the small baskets to allow a free flow of steam around and through the product. In this way the residence time for cooking and skin softening can be substantially reduced and an even penetration of heat obtained BELL PEPPERS (1) Flow-sheet Feed to Line Double flood was Deseeding Double Flood Wash Inspection Cutting Sulphating Drying Conditioning ning spectio Packin

desired to achieve complete cooking, and it incorporates a second tank where rubber rollers rub off the skin without damage to the flesh. Where autoclaves are used, these can be the standard canner’s horizontal type, with front loading. The standard retort crates should not be used, however, as the depth of beets will be too great for the heat to penetrate into the centre of the mass and proper cooking will not take place. Small stainless baskets with perforated bottoms should be used, of suitable size to fit in layers inside theretort crates but spacer battens should be used between each row of the small baskets to allow a free flow of steam around and through the product. In this way the residence time for cooking and skin softening can be substantially reduced and an even penetration of heat obtained. BELL PEPPERS (1) Flow-sheet Feed to Line I Double Flood wash I Splitting I Deseeding I Double Flood Wash I Inspection I Cutting I Sulphiting I Drying I Conditioning I Screening I Inspection I Packing I27

(2)Varieties. Yolo Y.-California Wonder. -Bell Boy. ( 3)Product Handling Peppers may be processed whilst green, or can be left to ripen to red Intermediate green/red peppers are sometimes processed but do not command the top market price for the dry material. he peppers are fed from field boxes into a bulk feeder, then elevated to a double flood washer which has compressed air fed into its base to aerate the water. Whole washed peppers are fed to a three channel inspection belt where they pass down the outer lanes for deseeding, and the halves are then delivered down the centre channel to a second flood washer which washes out the remaining seeds. Cleaned peppers are elevated from the floo washer on to an inspection belt where any residual seeds or pith are taken out manually. It is possible to core and deseed peppers by machine but unless the shape and size are very regular, these machines are not 100 percent effective, and manual handling is often preferred If tomatoes are included in the product mix, then a tomato washing and sorting line can be used for both products as indicated in Chapter 3 The peppers are then elevated toa]typecutter, which is particularly suitable for peppers, leaf vegetables and leeks After cutting into flakes with the J cutter(capacity 2000kg per hr. )the product is elevated into a sulphiting bath with the solution of sodium metabisulphite controlled to give a residual levelof 1250ppm(+/-250ppm in the end-Product After dewatering, the flakes pass to the dryer, then bins Afterdrying, the flakes areelevated to a vibratory screen for removing fines, and thence the main product is fed by vibratory conveyor on to an inspection belt. The number of belts will depend on required throughput Each 7 metre belt should handle 1.5-2kg of product over the total area of the belt at any one time. At a belt speed of 4 metres per minute, 60-80kg of product can be handled per hour, per belt (4)Drying Conveyor Dryer or Stove or Tray Dryer scaled according to a desired Input temperatures 85 C in first stage reducing to 50C at end of cycle. Conditioning at52°-54℃. Dry to6%to7% Ratio overall(Raw material as received: dry= 22: 1.) Drying Down ratio(Prepared material: dry =14: 1)

(2) Varieties. (3) Product Handling Peppers may be processed whilst green, or can be left to ripen to red. Intermediate greedred peppers are sometimes processed but do not command the top market price for the dry material. The peppers are fed from field boxes into a bulk feeder, then elevated to a double flood washer which has compressed air fed into its base to aerate the water. Whole washed peppers are fed to a three channel inspection belt where they pass down the outer lanes for deseeding, and the halves are then delivered down the centre channel to a second flood washer which washes out the remaining seeds. Cleaned peppers are elevated from the flood washer on to an inspection belt where any residual seeds or pith are taken out manually. It is possible to core and deseed peppers by machine but, unless the shape and size are very regular, these machines are not 100 percent effective, and manual handling is often preferred. If tomatoes are included in the product mix, then a tomato washing and sorting line can be used for both products as indicated in Chapter 3. The peppers are then elevated toa J typecutter, which is particularly suitable for peppers, leaf vegetables and leeks. After cutting into flakes with the J cutter (capacity 2000kg per hr.) the product is elevated into a sulphiting bath with the solution of sodium metabisulphite controlled to give a residual level of 1250ppm (+/- 250ppm) in the end-product. After dewatering, the flakes pass to the dryer, then to conditioning bins. After drying, the flakes are elevated to a vibratory screen for removing fines, and thence the main product is fed by vibratory conveyor on to an inspection belt. The number of belts will depend on required throughput. Each 7 metre belt should handle 1.5-2kg of product over the total area of the belt at any one time. At a belt speed of 4 metres per minute, 60-80kg of product can be handled per hour, per belt. (4) Drying Conveyor Dryer or Stove or Tray Dryer scaled according to a desired throughput. Input temperatures 85°C in first stage reducing to 50°C at end of cycle. Conditioning at 52" - 54°C. Dry to 6% to 7% Ratio overall (Raw material as received: dry = 22:l.) Drying Down ratio (Prepared material: dry = 14:l.) Yo10 Y. - California Wonder. - Bell Boy. I28

Cultivation Guidelines for Bell Peppers () Sowing Nursery Bed spacing: 6.5cm Plant out: 23-30cm apart in 75-100cm rows Apply 500kg per Ha of 12: 12: 17+2 at planting and side dress at 4-6 week intervals with 250kg per Ha of Sulphate of Ammonia or 12: 12: 17+2 (3) Herbicide Apply Dymid liquid formulation at 11 litres per Ha. (2kg active)or 2kg Diphenamid 80W(Dymid), either pre or postemergence, to clean ground (4) Pesticides Diazinon 60 EC against Leaf miner: Thrips: Aphid Endosulfan against flea beetles and caterpillars (5)Disease Control against bacterial leaf Dithane M45 or antrocol against mosaic virus. If virus is severe, uproot affected plants (6)Maturity California Wonder should be picked green but allowed to be fully mature before harvesting. If picked too young the fruit will wilt Yolo Y is left to mature to bright red Harvesting is 12-14 weeks from sowing/planting, onwards Plant population 30,000 per Ha CABBAGE (1) Flow-sheet Feed to Line Trimming Coring/ Quartering Rod washing Flood Washing Dicing

Cultivation Guidelines for Bell Peppers (1) Sowing Nursery Bed spacing: 6.5cm. Plant out: 23-30cm apart in 75-100cm rows (2) Fertilisers Apply 500kg per Ha of 12:12:17+2 at planting and side dress at 4-6 week intervals with 250kg per Ha of Sulphate of Ammonia or 12:12:17+2. (3) Herbicides Apply Dymid liquid formulation at 11 litres per Ha. (2kg active) or 2kg Diphenamid 8OW (Dymid), either pre or postemergence, to clean ground. (4) Pesticides Diazinon 60 EC against Leaf miner: Thrips: Aphids Endosulfan against flea beetles and caterpillars. (5) Disease Control Kocide 101 against bacterial leaf spot. Dithane M45 or Antrocol against mosaic virus. If virus is severe, uproot affected plants. (6) Maturity California Wonder should be picked green but allowed to bc fully mature before harvesting. If picked too young the fruit will wilt. Yo10 Y is left to mature to bright red. Harvesting is 12-14 weeks from sowing/planting, onwards. Plant population 30,000 per Ha. CABBAGE (1) Flow-sheet Feed to Line I Trimming I Coring / Quartering I Rod washing I Flood Washing I Dicing I Steam Blanching I I29

Sulphating Dewatering rying Conditioning eening Inspection Packing (2)Varieties As cabbage is now used mainly as a constituent in soups, both for flavour and eye appeal, it is necessary to select cultivars of bright green appearance when Another important requirement is that the head should be compact and ideally the core should not exceed 7-8 percent of the total trimmed weight. Very heavy trimming losses can arise from heavily cored ball- headed varieties, such as Primo and winnigstadt, and these should be avoided. Small compact heads, such as Celtic, Ice Queen, and January Queen are useful Savoy types with good colour. Hispi and Offenham are good early varieties, and Wiam a dark green mid-season type. Cabbage is grown almost worldwide and there will be many indigenous varieties which could process well, subject to the parameters set out on colour and absence of heavy core Dry matter is all important and 9-11 percent total solids is a figure to be aimed at when selecting raw material. (3)Product Handling Cabbage is brought to the factory in crates or tote boxes, and special attention should be given to the condition of these in the reception area, to ensure that wooden containers are not splintered Splinters of wood can cause damage to cutters, apart from contaminating the product. Cabbage nets are also a hazard as they tend to shed fibres, which are difficult to detect in the dry Cabbage should never be stored for more than ten hours at the factory ore processing As much trimming as possible of outer leaves should be done at the farms to avoid bringing extraneous waste matter into the factory. The first operation is to trim the cabbage of its four outer leaves on a suitable conveyor

Sulphiting I Dewatering I Drying I Conditioning I Screening I Inspection I Packing (2) Varieties As cabbage is now used mainly as a constituent in soups, both for flavour and eye appeal, it is necessary to select cultivars of bright green appearance when reconstituted. Another important requirement is that the head should be compact and ideally the core should not exceed 7 - 8 percent of the total trimmed weight. Very heavy trimming losses can arise from heavily cored ball￾headed varieties, such as Primo and Winnigstadt, and these should be avoided. Small compact heads, such as Celtic, Ice Queen, and January Queen are useful Savoy types with good colour. Hispi and Offenham are good early varieties, and Wiam a dark green mid-season type. Cabbage is grown almost worldwide and there will be many indigenous varieties which could process well, subject to the parameters set out on colour and absence of heavy core. Dry matter is all important and 9 - 11 percent total solids is a figure to be aimed at when selecting raw material. (3) Product Handling Cabbage is brought to the factory in crates or tote boxes, and special attention should be given to the condition of these in the reception area, to ensure that wooden containers are not splintered. Splinters of wood can cause damage to cutters, apart from contaminating the product. Cabbage nets are also a hazard as they tend to shed fibres, which are difficult to detect in the dry product. Cabbage should never be stored for more than ten hours at the factory before processing. As much trimming as possible of outer leaves should be done at the farms to avoid bringing extraneous waste matter into the factory. The first operation is to trim the cabbage of its four outer leaves on a suitable conveyor I30

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