Fruit and vegetable processing

Industry description and practices. Processing (canning, drying, freezing and preparation of juices, jams and jellies) increases the shelf life of fruit and vegetables. Processing steps include preparation of the raw material (cleaning, trimming and peeling followed by cooking, canning or freezing). Plant operation is often seasonal.

Waste characteristics. The fruit and vegetable industry typically generates large volumes of effluents and solid waste. The effluents contain high organic loads, cleansing and blanching agents, salt, and suspended solids such as fibers and soil particles. They may also contain pesticide residues washed from the raw materials. The main solid wastes are organic materials, including fruits and vegetables. Odor problems can occur with poor management of solid wastes and effluents; when onions are processed and when ready- to- serve meals are prepared.

Pollution prevention and control. Reductions in wastewater volumes of up to 95% have been reported through implementation of good practices. Where possible, measures such as the following should be adopted:

• Procure clean raw fruit and vegetables, thus reducing the concentration of dirt and organics (including pesticides) in the effluent.

• Use dry methods such as vibration or air jets to clean raw fruit and vegetables. Dry peeling methods reduce the effluent volume ( by up to 35%) and pollutant concentration (organic load reduced by up to 25%).

• Separate and recirculation process wastewaters.

• Use countercurrent systems where washing is necessary.

• Use steam instead of hot water to reduce the quantity of wastewater going for treatment (taking into consideration, however, the tradeoff with increased use of energy).

• Minimize the se of water for cleaning floors and machines.

• Remove solid wastes without the use of water.

• Reuse concentrated wastewaters and solid wastes for production of by- products.

As an example, recirculation of process water from onion preparation reduces the organic load by 75% and water consumption by 95%. Similarly, the liquid waste load from apple juice and carrot processing can be reduced by 80%. Solid wastes, particularly from processes such as peeling and coring, typically have a high nutritional value and may be used as animal feed.

Target pollution loads. Implementation of cleaner production processes and pollution prevention measures can yield both economic and environmental benefits.

Treatment technologies. Preliminary treatment of wastewaters should include screening ( or sieving to recover pulp) and grit removal, if necessary. This is followed by pH adjustment and biological treatment of the organic load.

The flows are frequently seasonal, and robust treatment systems are preferred for onsite treatment. Pond systems are used successfully to treat fruit and vegetable wastes, but odor nuisance, soil deterioration, and groundwater pollution are to be avoided. The quality of the effluent is normally suitable for discharge to municipal systems, although peak hydraulic loads may cause a problem. Odor problems can be avoided by using gas scrubbers or biofilters.

Emissions guidelines. Emissions levels for the design and operation of each project must be established through the environmental assessment process on the basis of country legislation. All of the maximum levels should be achieved for at least 95% of the time that the plant or unit is operating, to be calculated as a proportion of annual operating hours.

Liquid effluents. Pesticides may be present in significant levels; testing should therefore be performed, and, if pesticides are present at levels above 0.05 milligrams per liter (mg/l), corrective action should be taken. The best course may be to switch to a supplier that provides raw materials without pesticide residues.

Ambient noise. Noise abatement measures should achieve either the levels given below or a maximum increase in background levels of 3 decibels. Measurements are to be taken at noise receptors located outside the project property boundary.

Notes to the text

shelf life сохраняемость, лёжкоспособность

raw material сырьё

solid waste твёрдые отходы

suspended solids суспендированные твёрдые отходы

ready- to- serve готовый к употреблению

take into consideration принимать во внимание

in terms of в смысле, с точки зрения

GRAMMAR AND VOCABULARY EXERCISES

1. Answer the following questions:

1. What increases the shelf life of fruit and vegetables?

2. Why is plant operation often seasonal?

3. What do the effluents contain?

4. What are the main solid wastes?

5. What methods help clean raw fruit and vegetables?

6. Why is steam more preferable than hot water?

7. Where may solid wastes from peeling and coring be used?

2. Agree or disagree with the following statements. Give reasons for or against.

1. Dry peeling methods reduce the effluent volume and pollutant concentration.

2. The main solid wastes are inorganic materials, including fruit and vegetables.

3. Inorganic wastes should be used in he production of animal feed or organic fertilizers.

4. Odor problems cannot be avoided by using gas scrubbers or bio-filters.

5. Pesticides may be present in significant levels.

3. Choose the correct answer.

1. Preliminary treatment of wastewaters should … screening and grit removal.

a) conclude b) include c) involve

2. Monitoring data should be analyzed and reviewed at … intervals.

a) undue b) annual c) regular

3. Organic wastes should be used in the production of animal feed or … fertilizers.

a) organic b) inorganic c) new

4. Pond systems are used successfully to treat fruit and vegetable ….

a) odor b) wastes c) loads

5. … problems can be avoided by using gas scrubbers or bio-filters.

a) quality b) biological c) odor

4. Ask questions for these sentences.

1. Preliminary treatment of wastewaters includes screening and grit removal.

(What/ to include/)?

2. The flows are frequently seasonal.

(Why/ to be seasonal/)?

3. Monitoring of the final effluent is carried out at least once per month.

(When/to be carried out/)?

4. Monitoring data should be analyzed and reviewed and compared with the operating standards.

(What/ to be analyzed with/)?

5. Recirculation of process water reduces the organic load and water consumption.

(What/to reduce/)?

V. Make up a plan for retelling the text. Be ready to discuss it according to plan.

1. Read and translate the text paying attention to the following words and word combinations:

handling – обработка

spoilage – порча

maintain – сохранение

foodborne illness- заболевание пищевого происхождения

nutritional value — питательная ценность

density - густота; плотность; концентрация

flavor - 1) вкус; привкусы; 2) вкусовое вещество, ароматизирующее вещество, ароматизатор, отдушка

refrigeration - охлаждение; замораживание

to retard - замедлять; задерживать; тормозить

freezing - замораживание

reduction - снижение, понижение, сокращение

drying - высушивание; сушка

curing - консервирование, маринование, соление

packaging - упаковка

oxygen tension - давление кислорода

to inhibit - задерживать, сдерживать, препятствовать

lactic fermentation = lactic-acid fermentation - молочнокислое брожение

sucrose - сахароза

inactivation - лишение, подавление активности

ethanol - этиловый спирт, этанол

steeping - 1) замачивание; вымачивание; размачивание 2) пропитывание

emulsification - эмульгирование, эмульсация; эмульсификация

nutrient limitation - лимитирование питательными веществами

water-in-oil emulsion - эмульсия типа "вода в масле

radurization - консервирование ионизирующим излучением

radicidation - радиационная стерилизация (продуктов питания)

radappertization - радаппертизация, стерилизация ионизирующим излучением

hydrostatic pressure - гидростатическое давление

fungi (fungus) - грибы, плесень

discolo(u)ration - изменение цвета; обесцвечивание, выцветание

browning - чернение

recontamination - повторное загрязнение или заражение

denature - изменять естественные свойства

oxidation - окисление, оксидирование

dehydration - дегидратация; обезвоживание; сушка

spray drying - распылительная сушка

freeze drying - сублимационная сушка, сушка сублимацией

vacuum packing - упаковывание в вакууме

canning - консервирование

pickling - квашение, засол; маринование

smoking - копчение; обжарка в дыму