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The potential use of cabbage outer leaves as a starting material for the production of nanofibrillated cellulose (NFC) was investigated. Chemical‐free pretreatment methods, namely, autoclaving, ultrasonication (US), and high‐shear homogenization (HS), were applied to remove noncellulosic components from cabbage cell walls prior to defibrillation, which was conducted by subjecting a pretreated sample to HS and then high‐pressure homogenization. The sample undergone autoclaving at 130 °C for 2 hr was noted to contain a significantly higher cellulose content (36.5% dry mass) compared with the fresh leaves (12.48% dry mass). This led to an increase in the crystallinity index (CI) of the autoclaved cabbages from 30.8% to 50.7%. Further increase in the cellulose content (47.0% to 49.2% dry mass) was observed when subjecting the autoclaved sample to either US at 37 kHz for 1 hr, HS at 3800 × gfor 15 min or HS followed by US at the aforementioned conditions. After pretreatment and defibrilllation, a suspension of NFC with the diameters of 4 to 50 nm was obtained, with the CI of 59.1% to 66.7%. Such a suspension exhibited a gel‐like behavior with tan δ in the range of 0.12 to 0.13; the suspension exhibited a similar behavior to that prepared by the conventional chemical pretreatment method. NFC could be produced from cabbage outer leaves, which are an abundantly available by‐product of a vegetable processing plant, via the combined hydrothermal and mechanical pretreatment without the use of any chemicals. This chemical‐free preparation process is highly desirable as it leaves no residues in the product and causes no chemical waste that needs to be treated. Cabbage‐based NFC also exhibits similar characteristics to that prepared via a chemically treated route.

Influence of vegetable processing on pesticide residues in ready‐to‐eat vegetables studied at the experimental level does not necessarily reflect actual situation at household level. This study assessed influence of household vegetable processing practices on pesticide residues in ready‐to‐eat vegetables at household level in Arusha, Tanzania. Data on vegetable handling practices were collected through observations and physical interviews in 70 households. Samples of raw and ready‐to‐eat vegetables were collected from the households for pesticide residues analysis. Detectable pesticide levels were found in 46% of raw and 14% of ready‐to‐eat vegetable samples. Pesticide residues detected were in the groups of organophosphates (22.8%), pyrethroids (14.3%), organochlorines (7.14%), benzoic acids (7.14%), and carbamates (5.71%). Unauthorized pesticides (dichlorvos, tetramethrin, and bendiocarb) and environmentally persistent pesticide (dieldrin) were found at levels above their respective maximum residue levels. Washing of vegetables twice or more (p = .01) or peeling (p = .008) was significantly associated with reduction of pesticide residues. There was a significant association between occurrence of pesticide residues in ready‐to‐eat vegetables and washing of minor ingredients with the water used to wash major ingredients (p = .001). Household practices of washing of vegetables with portable water followed with peeling can reduce pesticide residue levels significantly.

BACKGROUND: In recent years, improved detection methods and increased fresh-cut processing of produce have led to an increased number of outbreaks associated with fresh fruits and vegetables. During fruit and vegetable processing, natural protective barriers are removed and tissues are cut, causing nutrient rich exudates and providing attachment sites for microbes. Consequently, fresh-cut produce ismore susceptible to microbial proliferation than whole produce.

Summary Fresh fruits and vegetables have been reported to possess a variety of bioactivities partly due to their high abundance of phenolics. However, traditional thermal pasteurisation during fruit and vegetable processing typically induces a pronounced loss of phenolic compounds. In contrast, nonthermal pasteurisation techniques, especially high hydrostatic pressure (HHP) processing, are beneficial to the retention of phenolics. In addition to more effectively keeping original freshness, flavour and colour of fruit and vegetable products to the greatest extent, in most cases, HHP processing and subsequent storage more effectively sustain the levels of phenolic compounds and antioxidant activity in fruit and vegetable products compared with thermal pasteurisation. Therefore, HHP processing has a huge potential to preserve fruit and vegetable products rich in phenolic compounds.

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.

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.

The comparative financial performance of cooperatives and investor-owned firms (IOFs) in the fruit and vegetable processing and the dairy industries was analyzed for the years 1976 through 1987. Contrary to theoretical expectations, the cooperatives in both industries were found to perform as well as or better than the comparable IOFs by profitability, leverage, and interest coverage measures. No clear evidence was found of the hypothesized overinvestment in fixed assets or pronounced moral hazard behavior in cooperatives. The lack of significant differences in profitability between the two types of firms suggests that cooperatives may be following goals similar to IOFs.

Disposal of high strength wastes has been a problem in the fruit and vegetable processing industries. We have designed and tested an inclined continuous anaerobic digester for the rapid treatment of unmodified wine stillage (21,000–25,000 mg COD per liter) and waste water from a pea blancher (20,000 mg COD per liter). The digester was successfully operated for periods up to 9 months using feed rates as high as 10.7g COD per liter per day (hydraulic detention time of 2.4 days). COD removal efficiency ranged from 95.9% to 99.5%, and effluent suspended solids were less than 800 mg per liter.