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The number of vegetable processing plants has increased during recent years in many countries. At the same time, fresh vegetable products have been implicated by epidemiologic investigations as sources of infection. Fresh vegetables are susceptible to microbial contamination after harvest due to their high water and nutrient contents. Contamination may occur at all stages during production. The aim of this study was to determine the level of surface contamination after cleaning in several fresh-cut vegetable processing plants, and to identify the critical points in the processes and operating rooms. Surface and environmental samples were taken from the plants after cleaning of the processing devices and surfaces. The levels of surface and air hygiene in the vegetable processing factories were determined with different rapid hygiene monitoring methods. The amounts of total aerobic bacteria, Enterobacteriaceae and β-glucuronidase-positive bacteria, yeasts and moulds on surfaces were measured using Hygicult® contact plates. ATP bioluminescence was measured luminometrically with an HY-LiTE®2 equipment. The number of microbes in air was measured with an MAS-100 sampler. The highest levels of total aerobic bacteria, yeasts, Enterobacteriaceae and β-glucuronidase-positive bacteria were detected on machines (cutters, peeling machines etc.). High mean values of ATP were detected e.g. on packaging surfaces (due to high values of wooden boxes) and on cutters. Most of the bacterial counts measured on the surfaces were unacceptable when using the Finnish surface hygiene guidelines as criteria. However, the results should be examined in the context of the type of production and the stage of operation also must be taken into account. Different hygiene areas ( FDA, 2008 ) should be separate enough to allow maintenance of good hygiene in cleaner areas while accepting lower hygiene levels e.g. in primary (early) washing steps. Despite this, the results show that there is a clear need to improve cleaning and hygiene practices in vegetable production. Several practical recommendations were given e.g. concerning cleaning, design of production areas, training of employees and self monitoring of surface hygiene. The information obtained will be used for improvement of practices in the cleaning of vegetable processing factories.

Field studies were conducted in the years 2003-2005 in the Experimental Farm of the University of Life Sciences in Lublin. Beans from four cultivars - ‘Paulista’ and ‘Hit’ (green pods) and ‘Korona’ and ‘Galopka’ (yellow pods) - were grown on fawn soil, formed of loess deposits, on chalky marls, containing 1.4% organic substances on average. There were six sowing terms, every 6-7 days starting from the middle of May to the end of June. French bean harvest was performed once, when about 75% of the pods on the plants were in the phase of technological maturity, which fell between the third ten days of July and the first ten days of September. From the plot and plant the number and yield of the pods were determined: total, marketable and non-marketable small pods, unshapely and overripe pods, as well as those with symptoms of disease. The highest total and marketable pod yields - on average, 15.45 and 11.06 t ha-1, respectively - were obtained from plants sown in the first ten days of June, whereas the lowest - 12.54 and 9.54 t ha-1 - were from those sown in the middle of May. As a result of performing a one-time French bean pod harvest, the share of non-marketable pod yield in the total yield was on a similar level (24-28%), depending on the growing term. Variability was demonstrated in the share of particular non-marketable yield fractions (small pods, undersized, unshapely, and overripe pods, as well as those with disease symptoms), depending on the sowing date. Growing four French bean cultivars from sowing in the period from the middle of May to the end of June allowed us to extend the period of fresh pod harvest to six or seven weeks.

The study was conducted in Urban Community of Niamey at modern and semi-modern farms provided an overview use of agro-industrial by-products in animal feed. Among 57 farms only 17 farms, including 10 beef farms, 2 sheep farms and 5 poultry farms were systematically surveyed. All farm managers are men. 60 and 33% are respectively officials at the level of poultry farms and ruminant farms. Farmers make up 25%, all of which own beef farms. There is also a predominance of adults, 60% at poultry level and 58.33% at ruminant farms. We note the use of a variety of agro-industrial by-products in animal feeds, in this case by-products derived from vegetable processing (wheat bran, exfoliated cotton cake) and animal processing (fish and fish meal ...). There are also some concentrates for poultry feed. Agribusiness by-products are increasingly used in urban livestock production but their valorization needs to be improved.

In a previous study, Howland and Nguyen showed that cities that attracted Asian immigrants experienced slower declines in computer employment than did cities without immigration. This article continues this exploration of the role that immigrants play in labor supply and regional growth by applying a similar framework to four additional low-wage manufacturing industries. Results show that job retention and creation in three low-skilled industries—fruit and vegetable processing, apparel manufacturing, and leather and leather products manufacturing—respond to the influx of Hispanic immigrants in metropolitan areas. Asian immigration had no impact on these three industries, and neither Hispanic nor Asian immigrants affected metropolitan employment growth in the meat-processing industry.

In developing country like India, agriculture is the main stay of the economy. Agricultural industries and related activities can account for a considerable proportion of their output. The main objective of fruit and vegetable processing is to supply wholesome, safe, nutritious and acceptable food to consumers throughout the year. Processing requires frequent handling, high temperature and pressure. Many of the ordinary varieties of tomatoes, for instance, are not suitable for making paste or other processed products. Simulation was carried out for the updated model for a period of ten days with five replications. From the results obtained from the design of experiments, noises in the factors (steam losses, minor stoppages) were reduced by implementing the mentioned techniques. The runs are randomised using MINITAB software. A cost matrix was made to create a trade-off between all factors that were affecting the performance. This resulted in the increase of throughput rate in the real scenario. This research project demonstrates the practical application of design of experiments showing how it can bring real breakthroughs in productivity of fruit (tomato) processing industry.

When assessing the quality of fruit and packaging process, fruit-producing farms owners decide to evaluate fruit by people or automated sorting lines. The purchase of an automated sorting line generates high costs for the company, but it brings benefits in the form of increased work efficiency, and the better organization of fruit packaging and storage processes. The use of that machinery and equipment is common in agricultural farms as well as in fruit and vegetable processing companies. Despite the widespread use of various types of fruit sorters, the analysis of the operation of the designed device and the study of its technological parameters is still a current research problem. During operation of the devices for sorting fruit there are many technical problems affecting technological processes and quality of fruits. In order to improve the efficiency of sorting fruit, this process should be quickly and accurately. The purpose of this paper is to present the automated apple sorter line construction design, and software for quality controlling fruits. Selected elements of the sorter structure including endurance calculation using the Finite Element Method (FEM) and fruit control system using image analysis were presented.

Adoption of ozone technologies as Food Safety treatments in the Agri-Food Industries today is still being approached with great caution. This paper reviews selected successes in using ozone UV and advanced oxidation to enhance food safety and reduce energy costs in the Agri-Food industry. Included is a preliminary case study of utilizing ozone and chlorination in a FTNON vegetable washing system. Vegetable flotation washing systems such as the FTNON equipment produced by Noord-Oost in the Netherlands have the potential to vigorously wash sand as well as floating particulate from vegetables and fruits. With minor modifications these machines can be adapted to utilize combinations of ozone, UV and chlorination. Preliminary trials indicate plate counts are lowered with the combination treatment. Future data will need to be collected to determine the levels of chlorination required to ensure residual microbial protection without detracting from product taste and quality. When developed, these systems have the...

The present study is an attempt to examine the status and growth in fruit & vegetables production, processing capacity and growth and instability in exports. The study is based on secondary data collected from several published and website sources. The production of fruit has grown at an annual compound growth rate of 3.76 and of vegetables at 3.34 per cent, respectively during 1980-2006. The growth of fruit production has been more in India than world production whereas in case of vegetables production it is reverse. Now, it's processing which has assumed paramount importance for commercial exploitation by creating time, form and space utilities. Production of processed fruit & vegetable products has increased at an annual compound growth rate of 11.25 per cent. Capacity of fruit & vegetable processing units increased by 8.5 per cent per annum still the industry has been able to utilize only half of the installed capacity. India witnessed substantial increase in export value of processed fruit & vegetables (16.85% CGR) during the period under study. Dried & processed vegetables ranked first in India's total export of processed fruit & vegetable products in value terms whereas in quantity terms pickles & chutneys occupied first position. The existence of relatively high instability in exports was also witnessed which has implications for promoting exports from the country. In spite of impressive growth in exports, our share in world exports is very low which needs to be increased by taking appropriate research and development policies and relaxing the constraints faced by the processing industry.

The use of by-products from fruit and vegetable processing plants as sources of dietary fiber and bioactive agents is currently of interest, both from the waste management and from the production of value-added products points of view. This work aimed at studying the use of lime residues and outer leaves of white cabbage to produce dietary fiber powder, which included the study of the product pretreatment and preparation, drying, and grinding dried residues into powder. Dietary fiber content during each processing step was determined to calculate the loss of functionality of the products through the process. Hydration properties, i.e., water holding capacity (WHC) and swelling capacity (SWC), of the two residues were also determined after hot air drying at 60–80°C. The effect of particle size of dietary fiber powder, which was obtained by grinding dried residues, in the range of 63–450 μm, on the hydration properties was also evaluated and discussed.

Wash water from a fresh‐cut vegetable processing plant was filtered using a submerged microfiltration module containing PVDF membranes. The unfiltered water and permeate were analyzed and the flux and fouling rate were monitored in an effort to find the ideal parameters for the system. The study found the system had a pure water rate of 24 L/hm2 which was reduced to 19 L/hm2 after 6 hours with cleaning, when run at 40–50 kPa. The ideal cleaning regime was found to be every 1 hour for a period of 120 seconds at 200 kPa.

Throughout the fruit and vegetable processing industries, improving processing efficiency requires the development of in-line sensor technologies. The goal of this study was to determine if there is a basis to develop nuclear magnetic resonance (NMR) sensor technology based on spin–spin relaxation times to assist in quality sorting of processing tomatoes. The specific objectives were: to determine if firmness is an adequate indicator of maturity, to assess the effect of common defects on fruit firmness and NMR spin–spin relaxation time ( T 2 ) and to correlate firmness values and T 2 values. The study spanned three processing seasons and evaluated a number of standard processing varieties. To evaluate firmness, whole fruit compression tests were performed; NMR spin–spin relaxation times ( T 2 ) were determined using a CPMG pulse sequence and mono-exponential fitting. During the first season, a reasonable correlation was found between T 2 and peak force ( R 2 ≥ 0.75) using sound red fruit. Therefore, the study was expanded in 2005 and 2006 to include more processing varieties, maturity levels and common defects. Analysis of variance was performed on the responses, T 2 and peak force. In general, there were statistically significant differences in the mean values of the spin–spin relaxation times at the P = 0.05 level, yet these differences were small in magnitude. In addition correlation between NMR spin–spin relaxation time and fruit firmness in both 2005 and 2006 was poor. Neither of these experimental results supports continued development of an NMR sensor based on spin–spin relaxation time differences for in-line sorting of processing tomatoes.

Ozone, a powerful oxidant, is effective against various kinds of microorganisms on fruits and vegetables. Promising results have been revealed in solving the problems of the food industry like mycotoxin and pesticide residues by ozone application. Spontaneous decomposition without forming hazardous residues in the treatment medium makes ozone safe in food applications. If improperly used, ozone can cause some deleterious effects on products, such as losses in sensory quality. Treatment conditions should be specifically determined for all kinds of products for effective and safe use of ozone.

Drying is a necessary technology and a very energy-demanding process in the area of meat and vegetable processing; it is a tool for finishing semiprocessed or processed goods. Taking the given conditions into consideration, development of technology is necessary, which serves several aims that are often in disagreement with each other (in terms of improvement of availability value, avoidance of artificial additives, energy optimization, reduction of other cost factors, etc.). Until now, several scientific works have been published serving solutions for one specific problem of practice. The main idiosyncrasy of these works is the difference between their methods and availability; hence these are unsuitable to give a uniform model for products with different physical-biological properties: because, it goes without saying, circumstances of their birth as well as their aims differ so much. Computer support nowadays allows us to build a uniform model based on previous research and auxiliary measurement results, which can simulate the drying process of some of the most important agricultural products. Copyright © 2007 Curtin University of Technology and John Wiley & Sons, Ltd.

The effect of washing, peeling and cooking on residue levels of chlorpyrifos and 3,5,6-trichloro-2-pyridinol (TCP) in winter (spinach, cauliflower, potato) and summer vegetables (eggplant, tomato, okra) was determined. Analysis was carried out by capillary gas chromatography (DB-5MS capillary column) with mass selective detection. The samples were collected from trials conducted under controlled conditions as well as from the farmer’s field. In supervised field trials, the highest chlorpyrifos residue was found at raw stage in spinach (1.87 mg kg −1 ) followed by okra (1.41 mg kg −1 ) and eggplant (1.25 mg kg −1 ). The lowest residue of chlorpyrifos was recorded in cauliflower (0.036 mg kg −1 ). The chlorpyrifos residue reduced from 15 to 33% after washing, 65–85% post-peeling and cooking further lowered it from 12% to 48% in all the tested vegetables; while an increase in TCP concentration was observed during heat treatment. Out of 267 vegetable samples collected from the farmer’s field, 225 samples contained detectable residues representing 84% rate of contamination. About 6% of samples contained chlorpyrifos residues above maximum residue limits (MRLs). However, vegetable processing reduced the chlorpyrifos residue below the MRL.

Fruits are appreciated for their organoleptic and nutritional characteristics as minerals, vitamins, sugars, and other beneficial components (Klavons et al. 1991). Worldwide production of fruit recorded growth from 420 million tons during 1989-1991 to 500 million tons in 1996, 724.5 million tons in 2009 and 728.4 million tons in 2010. The three largest fruit producers in the world are China, India, and Brazil, which contribute with 43.6% of the world’s total production; however, they basically cater to their domestic markets (FAO 2012; IBGE 2012). It is estimated that 25% to 80% of harvested fruit is lost during transportation and storage due to its high perishability; and hence, they require special care in both postharvest storage and processing (Cardoso 2011). In this context, processing of fruits and vegetables has improved with the production of juices, pulps, purees, jelly, dried fruit, sweets, and jams, which allows uninterrupted consumption, waste reduction, and increased consumption of processed products (Kosseva 2009).

This chapter documents an example of technical assistance provided by a private-sector firm in Brazil to help small-scale farmers increase their productivity and market access, thereby increasing their income. The public extension system in Brazil has undergone a major set of reforms in the past 20 years in order to meet the extension and advisory service needs of small-scale farmers. The extension and advisory needs of large-scale commercial farmers are met directly by commercial input suppliers, a structure similar to those found in developed countries. In this case study we look at Rio de Una, a private vegetable processing company located in the Parana state of Brazil, to better understand the role of private actors in providing technical assistance to smallholder farmers in Brazil and to document lessons that can be learned from Rio de Una’s technical assistance practices. This case study is the result of a series of interviews with Rio de Una’s management, technicians, and farmers in an effort to understand the relationship between Rio de Una and farmers, the technical services provided, what changes this relationship has brought, and the linkages between these services, public policies, and the overall extension services provided in the region.

PurposeThis paper aims to focus on the prospects of incorporating a non‐thermal process (high intensity electric field pulses, HELP) into food processing and preservation methods in developing countries. Besides, it is to create awareness to food processors and motivate researchers in developing countries to generate more data on the technology.Design/methodology/approachThis is based on the review of the various successful applications of HELP process in inactivation of micro‐organisms for the purpose of preservation. The adaptability of the process to plant food processing was also reviewed. Potential areas of application in developing countries were also highlighted and discussed.FindingsThe present findings reveal possible applications of HELP to food processing in developing countries such as fermentation, fruit and vegetable processing, and dehydration of tropical food.Originality/valueThe paper has indicated that the poor energy system in developing countries has made drying and fermentation techniques appropriate methods of food processing. Therefore, HELP technology offers good potentials for both food processing and preservation and as adjunct to other processes such as fermentation and drying.

Vacuum impregnation (VI) is considered as a useful technique to quickly introduce external liquids in the porous structures of animal and plant tissues, in a controlled way. As consequence some mass transfer processes (as dewatering) are improved and also some changes in food composition may be produced. VI has broad applications in fruit and vegetable processing and provides many unique advantages. This review analyzes the main factors and responses of porous fruits and vegetables to VI processing, summarizes important developments related to VI applications in the fruit and vegetable industry, and discusses quality aspects of VI processed fruits and vegetables, as well as technical challenges and future research needs in this field.

Fluorescent lamp that is coated with a photocatalyst film, titanium dioxide (TiO2), can catalyze the microorganisms and smell producing molecules that touch the membrane. In this report, we examined the effect of this coated lamp by the number of floating microorganisms or smell molecules in a room installed with this lamp. The number of floating microorganisms was examined independently in different laboratories before and after installing the lamps in an animal facility and a vegetable processing room of a food company. We found that the number of floating microorganisms was significantly reduced after the installation of this coated lamp. To test for smell molecules, acetaldehyde was injected into a closed chamber installed with the coated lamp and the result was compared to a control where a regular fluorescent lamp was used. The acetaldehyde concentration did not change with the regular lamp but was halved after 1h with the photocatalyst coated lamp. To test the effect in real settings, questionnaires were filled out by restroom users in several different places. About 90% of those surveyed answered that there was a reduction of smell after the installation of the photocatalyst coated lamp. We concluded that the installation of this coated fluorescent lamp reduced not only the floating microorganisms but the smell in various practical situations.

Best available techniques (BAT) are an important reference point in the environmental permit regulation for industrial installations in the European Union Member States, which have to implement the integrated pollution prevention and control (IPPC)-directive (96/61/EC). BAT correspond to the techniques and organisational measures with the best overall environmental performance that can be introduced at a reasonable cost. In the Flanders part of Belgium, BAT are usually determined at the sector level. The ‘Fruit and Vegetable Processing Industry’ [BAT for Fruit and Vegetable Processing Industry. Gent, Belgium: Academia Press, 1999] is one of the industries for which a BAT report has been drafted. In this paper, the main results of this study are presented. Special attention is given to the use of high quality water 1 , as this is the key environmental issue of the industry.

Application of HPP for raw and RTE meat and poultry products, fruits and vegetable processing, cold pressed juices, seafood and dairy categories are discussed. The range of operating pressures to be applied to achieve shelf-life extension, pasteurization, and nonthermal extraction treatments of different categories of finished and raw seafood products are presented.

Vacuum cooling is a rapid evaporative cooling technique, which can be applied to specific foods and in particular vegetables. Increased competitiveness together with greater concerns about product safety and quality has encouraged some food manufacturers to use vacuum cooling technology. The advantages of vacuum cooling include shorter processing times, consequent energy savings, improved product shelf life, quality and safety. However, the cooling technique has a limited range of application. Traditionally, products such as lettuce and mushrooms have been cooled under vacuum. Recent research has highlighted the possible applications of vacuum cooling for cooling meat and bakery products, fruits and vegetables. This paper comprehensively reviews the current state of the technology. It is concluded that while vacuum cooling remains a highly specialised cooling technique, with continuing research its application may make its use in the food and vegetable processing industries more competitive and widespread.

Fruit-processing wastes including apple pomace, cranberry pomace and strawberry pomace were used as substrates for polygalacturonase (PG) production by Lentinus edodes through solid-state fermentation. Strawberry pomace was the best substrate for highest PG yield, followed by apple pomace, while cranberry pomace was not a suitable substrate for PG production in this study. The highest PG activity was obtained after 40 days of culture and the yields from strawberry pomace, apple pomace and cranberry pomace were 29.4 U, 20.1 U and 14.0 U per gram of pomace, respectively. PG activity was increased by the addition of polygalacturonic acid in the apple pomace and cranberry pomace media, but was not affected in strawberry pomace medium. The PG produced by L. edodes from strawberry pomace exhibited a maximal activity at 50°C and at pH 5. The enzyme was fairly stable up to 50°C and between pH 3.0 and 6.5. The acid tolerant property of the enzyme made it suitable for applications in most fruit and vegetable processing industries. This value-added bioconversion strategy may be applicable for the utilization of other food processing wastes.

Food waste samples were collected approximately bimonthly from five different New Jersey farms that feed food waste to pigs. All of these farms feed food waste collected from various institutions (restaurants, casinos, military bases, hospitals, and nursing homes) and often supplement with other byproduct feeds such as bakery, fish cannery, or vegetable processing wastes. A total of 63 samples were collected and analyzed for nutrient content in laboratories at the New Jersey Agricultural Experiment Station. Results from all five farms indicated that food plate wastes often have an acceptable nutritional profile. Crude protein averaged in excess of 20% and EE over 25%. Fiber levels were low and most minerals were borderline, if not adequate, for growing pigs. However, the low DM (27%) and the high variability of nutrients (CV often near or in excess of 100%) were significant limitations. For individual farms, DM percentage was always low, EE was high, and CP was variable. Mineral levels also varied from farm to farm. Calcium averaged 1.69% in food waste collected by Farm 1 and 0.36% in food waste collected by Farm 2. Several of the trace nutrients (copper, iron, zinc) were also variable. Zinc samples averaged 28 mg/kg on Farm 2 and 146 mg/kg on Farm 1. Zinc levels in food waste fed on Farms 2 through 5 were all inadequate when compared to NRC levels for growing pigs. Essential amino acids were, on average, equal to or above NRC levels required for growing pigs, except for lysine levels in food waste, which were below requirements on Farms 1 and 2. Results from this work have helped to develop a nutrient profile of the food waste currently fed to swine in the state of New Jersey and have been shared with individual producers. Food waste, although often of ample nutritional quality, is limited by its low DM and variable nutrient content, and should be monitored regularly and supplemented accordingly in practical feeding situations.

Ascorbigen, one of the most important indole derivatives of Brassica vegetables, is formed by an enzymatic degradation of indole glucosinolate glucobrassicin followed by a subsequent spontaneous reaction between indole-3-carbinol and l -ascorbic acid. Experiments, carried out in model solutions simulating in vitro conditions during vegetable processing, indicated the increasing rate of ascorbigen formation with decreasing pH of solution. Ascorbigen was shown to be very labile at higher temperatures and its enhanced stability in acidic medium was evident.

Water recyling in fruit and vegetable processing may contribute to decreasing industrial waste and load. Water was recycled for washing orange peel to prepare a high dietary fibre powder using tap water washing as the standard. Total sugar (12.1-13.1%), total dietary fibre (70-71.5%), soluble dietary fibre (21-22%), yield (59-60%), water holding capacity (7.8-8.1 g water g -1 dry matter), colour and microbiological quality of a dry product were not significantly affected when the liquors from pulping and pressing were recycled for washing peel. Recycling liquors from pulping and pressing gave the highest energy (43%) and water (33.4%) savings, respectively.

A general framework is provided for assessing the technology, cost, and efficient scale of a multiplant, multiproduct firm. We show sufficient conditions for the existence of a plant cost function, and necessary and sufficient conditions for using plant-level data to draw exact firm-level cost inferences. We also distinguish between plant and input nonjointness and show the optimal relation between plant-level and firm-level cost elasticity in a multiproduct setting. The framework is applied to a vegetable processing cooperative, which is found to operate below its efficient scale.

Folates (B vitamins) are essential for the proper function of many bodily processes. Although a rich natural source are vegetables, the literature lacks data on the effect of the pre-treatment and freezing technologies used in vegetable processing and frozen storage time on the folate content in these materials. Moreover, since folates are very unstable nutrients, the amount available in processed and stored foods can be significantly lower than in raw products. In tested vegetables (green beans, yellow beans, peas, cauliflower, broccoli and spinach), one folate form was identified, 5-methyltetrahydrofolate (5-CH3-H4folate). It was observed that pre-treatment and freezing technology significantly (p

Publication Inra prise en compte dans l'analyse bibliométrique des publications scientifiques mondiales sur les Fruits, les Légumes et la Pomme de terre. Période 2000-2012. http://prodinra.inra.fr/record/256699; This study was conducted to evaluate quality and structural changes in parallelepipedic pieces of pears during convective drying at different air temperatures (30-70 degrees C). Submitted to atmospheric O-2 conditions, ascorbic acid deterioration demonstrated first-order kinetic behaviour and was found to depend on air temperature and pear moisture content. Loss of ascorbic acid content increased with increasing air temperature. Possible explanation could be the irreversible oxidative reaction occurring during drying. Phenol content degradation fitted a pseudo first-order reaction and was significantly influenced by air temperature. Variations in bulk density, shrinkage and porosity essentially depended on changes in moisture content. Porosity exhibited a nonlinear variation with respect to moisture content. Volume change showed, as expected, a linear variation with moisture content. Drying temperature significantly induced the increase of a* and b* colorimetric parameters due to non-enzymatic browning reaction, which turned the samples more reddish and yellow when the temperature rose. (C) 2011 Published by Elsevier B.V. on behalf of The Institution of Chemical Engineers.

The basic principles which control osmotic dehydration of fruit and vegetables are reported together with the most important parameters and their influence on the process. The effects of osmosis as a pre-treatment, mainly related to the improvement of nutritional, sensorial and functional properties of the products, are analyzed. The distinctive aspect of this process, when compared to other dehydration methods, is the ‘direct formulation’ achievable through the selective incorporation of solutes, without modifying the food integrity. By balancing the two main osmotic effects, water loss and soluble solids uptake, the functional properties of fruit and vegetables could be adapted to many different food systems. Present applications of the process are shown and problems related to a further industrial development are analyzed.

The effect of feeding different fruit and vegetable wastes, mango, pineapple, tomato, jackfruit, banana and orange, was studied in a 60-liter digester by cycling each waste every fifth day in order to operate the digester as and when there was supply of feed. The characteristics of the anaerobically digested fluid and digester performance in terms of biogas production were determined at different loading rates (LR) and at different hydraulic retention times (HRT), and the maximum biogas yield of 0·6 m 3 /kg VS added was achieved at a 20-day HRT and 40 kg TS m −3 day −1 loading rate. The hourly gas production was observed in the digesters operated at 16 and 24 days HRT. The major yield (74·5%) of gas was produced within 12 h of feeding at a 16-day HRT whereas at a 24-day HRT only 59·03% of the total gas could be obtained at this time.

Waste recovery using vegetable matter, or ‘bioadsorbents’, is not yet efficient or economic but efforts are being made to improve the functionality of bioadsorbents, through either their natural adsorptive components or by combining raw materials. A promising approach for waste management and waste water, treatment is described which involves adsorption of compounds such as volatile organic carbons (VOCs) on bioadsorbents.