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Recent studies on gelation and interfacial properties of vegetable protiens are reviewed. Attention is focused on legume proteins, mainly soy proteins, and on wheat proteins. The rheological properteis of vegetable protein gels as a function of heating time or temperature is discussed as well as the interfacial gelation upon adsorption of soy and wheat proteins at the air/water interface. It is shown that modification of proteins improves functionality and application. ©2002 Elsevier Science Ltd. All rights reserved. Chemicals/CAS: glycinin, 9007-93-6; soybean protein, 9010-10-0; water, 7732-18-5

Soy protein is the vegetable protein that is most frequently used in meat products. Accordingly, detection and determination procedures have mainly been focused on soy proteins. Cereal proteins received far less attention analytically, let alone the less conventional vegetable proteins. Every method published has only a limited applicability, determined by both the type of soy preparation concerned and the heat processing of the sample. The methods may be divided into five categories. 1. Chemical methods are based on analysis of tracer substances accompanying the soy proteins by nature. Their specificity is rather low; other vegetable proteins may contain the same substances. Soy flour, concentrates and texturates respond quantitatively, and sometimes even qualitatively, different. The methods are almost useless for isolated soy proteins. 2. Microscopic methods may allow rapid detection of soy products except isolates. They may be used for quantitation purposes. However, representative results will only be secured at the expense of time and labor. 3. Electrophoresis methods rely on the recognizability of soy protein bands in the pherogram pattern. Field of application and specificity are satisfactory. Efficient media enable complete solubilization of soy protein from meat products, if not severely heat-processed. 4. Immunochemical methods, although very sensitive and specific, are only suitable for detection purposes, provided the sample temperature did not exceed 100 C during processing. This holds, of course, only true if the soy produced used is not excessively heated during preparation. 5. Methods based on amino acid composition or sequence are based on computer matching of the amino acid pattern of the meat product sample with those of varying mixtures of all proteins that could be contained in the sample. ?? 1979 The American Oil Chemists' Society. Chemicals/CAS: amino acid, 65072-01-7; Amino Acids; Vegetable Proteins

Plant sterols are added as their FA esters to vegetable oil table spreads at levels of approximately 8% as a means to reduce blood cholesterol levels. A new chromatographic method was designed to quantify quickly the level of plant sterol FA esters in incoming (raw) materials and to monitor their processing and final product quality with respect to total sterol level. The method shows a significant improvement in elapsed time and thus labor cost over the classical methods for sterols published in normative references. This improvement was obtained together with high performance characteristics, as shown by the internal method validation for recovery and repeatability. Its validity and robustness were further tested and confirmed in an international collaborative test. The method allows monitoring of sterol content of raw materials, fat-blends, and consumer products at the target level, with a range of 10% or less around this target. The calculated within- and between-laboratory reproducibility were 0.680 and 1.194 w/w%, respectively, for sterol-containing spreads. The results afforded by this method can be used for setting tight product specifications or to monitor trade between companies. We propose to add this new and fast method for total 4-desmethyl sterol(s) to analytical method collections as an adjunct to methods already listed for more detailed sterol analysis.

A fast and sensitive high-performance liquid chromatographic (HPLC) method for the determination of the provitamin A, ??-carotene, in vegetables is described. After alkaline saponification and organic extraction ??-carotene is separated from other carotenoids on a reversed-phase HPLC column and determined by measurement of its absorbance at 445 nm. The total amount of carotenoids is determined by measurement of the absorbance at 445 nm of the extract prior to HPLC. Results are presented of the analysis of ??-carotene and total carotenoids in some vegetables bought at a local market in Dar es Salaam. The percentage ??-carotene, of the total carotenoid content, showed a great variation. The vitamin A activity of the vegetables was calculated from the analytical results. Chemicals/CAS: beta carotene, 7235-40-7; retinol, 68-26-8, 82445-97-4Chemicals/CAS: beta carotene, 7235-40-7; retinol, 68-26-8, 82445-97-4

Counselor competence in telephone Motivation Interviewing (MI) to change lifestyle behaviors in a primary care population was assessed using the Motivational Interviewing Treatment Integrity (MITI) rating system. Counselor behavior was evaluated by trained raters. Twenty minutes of a random sample of 336 MI sessions were coded representing 232 counselees. Ninety-four sessions (28%) were double coded to assess inter-rater agreement. The MI fidelity was examined by comparing the MI fidelity scores direction, empathy, spirit, % open questions, % complex reflections, reflections-to-questions ratio, % MI-adherent responses with the matching beginner proficiency MITI threshold. The inter-rater agreements for the MI fidelity summary scores were good (spirit, reflections-to-questions ratio), fair (empathy, % open questions, % MI-adherent responses) or poor (direction, % complex reflection). The MI fidelity scores for direction, empathy, spirit and the percentage of complex reflections exceeded the MITI threshold, but lower scores were found for the percentage of open questions, the reflections-to-questions ratio and the percentage of MI-adherent responses. In conclusion, evidence that MI was implemented was revealed. However, the inter-rater agreements scores and some fidelity scores leave room for improvement indicating that raters and counselors may need more ongoing training and feedback to achieve and maintain adequate competence. These findings apply to more complex skills (as rating complex reflections) in particular.

Background: Computer tailoring and motivational interviewing show promise in promoting lifestyle change, despite few head-to-head comparative studies. Purpose: Vitalum is a randomized controlled trial in which the efficacy of these methods was compared in changing physical activity and fruit and vegetable consumption in middle-aged Dutch adults. Methods: Participants (n?=?1,629) were recruited via 23 general practices and randomly received either four tailored print letters, four motivational telephone calls, two of each type of intervention, or no information. The primary outcomes were absolute change in self-reported physical activity and fruit and vegetable consumption. Results: All three intervention groups (i.e., the tailored letters, the motivational calls, and the combined version) were equally and significantly more effective than the control group in increasing physical activity (hours/day), intake of fruit (servings/day), and consumption of vegetables (grams/day) from baseline to the intermediate measurement (week 25), follow-up 1 (week 47) and 2 (week 73). Effect sizes (Cohen's d) ranged from 0.15 to 0.18. Participants rated the interventions positively; interviews were more positively evaluated than letters. Conclusions: Tailored print communication and telephone motivational interviewing or their combination are equally successful in changing multiple behaviors. © 2010 The Author(s).

This paper describes a design proposal for adapting the OGEGU Food Production Unit (FPU) to the surface of Mars in order to produce up to 40% of the diet for a six-member crew by growing a pre-defined set of vegetable food species. The external structure, lighting system and plant support system are assessed using ESM analysis. The study shows that the mass of an FPU operating on the Mars surface, featuring an opaque inflatable structure plus all the required subsystems and equipment, is in the order of 14,000 kg. The required volume is around 150 m3 and the power consumption is around 140 kW. A reduction of c. 20 kW could be obtained by exploiting natural light using transparent materials. Finally, the paper concludes with the identification of some technological gaps that need to be investigated further for the purpose of establishing a feasible FPU on Mars. Copyright © 2005 SAE International.

An enzyme-linked immunosorbent assay for the detection of mustard protein was developed. The assay is based on a polyclonal antiserum directed against a mixture of mustard proteins raised in rabbits. The assay has a detection limit of 1.5 ppm (milligrams per kilogram) and is suitable for the detection of traces of mustard protein in mustard seed-derived flavoring ingredients. Limited cross-reactivity testing showed that no other plant proteins reacted significantly. From the animal proteins tested, only milk showed some cross-reactivity. With this sensitive assay, it was shown that refined mustard seed oil produced by steam distillation does not contain detectable amounts of mustard protein. Mustard seed oil is used as a flavoring in very low quantities, typically between 40 and 200 mg/kg. Thus, 100 g of a food product flavored with 200 mg of mustard seed oil per kg containing <1.5 mg of protein per kg would represent an amount of mustard seed protein of <30 ng. Taking into account the published literature on allergic reactions to the unintended ingestion of mustard, this conservatively low calculated level indicates that it is unlikely that food products containing mustard seed oil as a flavoring ingredient will elicit an allergic reaction in mustard-allergic individuals. Copyright ©, International Association for Food Protection.

Vegetable and fruit consumption is generally inversely associated with various cancer types, including renal cell carcinoma (RCC). The Netherlands cohort study on diet and cancer (NLCS) consists of 120,852 men and women, aged 55-69 years, who filled out a self-administered questionnaire that includes ISO-item food-frequency questions and additional questions on lifestyle factors, at baseline in 1986. A case-cohort approach was used. After 9.3 years of follow-up, 275 microscopically confirmed incident cases were identified. Subjects with incomplete or inconsistent dietary data were excluded, leaving 260 RCC cases for analyses on fruit consumption and 249 RCC cases for analyses on vegetable consumption. Incidence rate ratios (RR) and corresponding 95% confidence intervals (CI) were estimated using Cox proportional hazard models. RRs for exposure variables are expressed per increment of 25 g/day and are adjusted for age, sex, smoking, body mass index and history of hypertension at baseline. The RRs for vegetable consumption were further adjusted for fruit consumption and vice versa. Total vegetable and fruit consumption (RR: 1.00; 95% CI 0.97-1.02), vegetable (RR: 1.00, 95% CI 0.96-1.06) and fruit consumption (RR: 1.00; 95% CI 0.97-1.03) were not associated with RCC risk. Also, no association existed for botanical subgroups of vegetables and fruit. For 30 individual vegetables and fruits, we observed one that significantly increased RR (mandarin consumption, RR: 1.76; 95% CI 1.28-2.42), which must be regarded cautiously because of multiple testing. These results suggest the absence of an association between vegetable and/or fruit consumption and RCC risk. © 2005 Wiley-Liss, Inc.

An intercomparison study on the determination of vitamin B-1, B-2 and B-6 was performed as part of the EU MAT project involving 16 laboratories. Each laboratory was requested to analyse three different food samples (lyophilized pig's liver, mixed vegetables and wholemeal flour, respectively) using their 'in-house' method as well as an 'optimal extraction protocol' and using a common batch of takadiastase enzyme. High-performance liquid chromatography (both normal-phase and reversed-phase HPLC), microbiological assay and chemical methods were used. For vitamins B-1 and B-2 the agreement between laboratories (using their 'in-house' methods) was generally good (vitamin B-1: CV(w) < 5%, CV(b) = 16-28%; vitamin B-2: CV(w) < 8%; CV(b) = 12-40%, respectively, where CV(w) is the within-laboratory coefficient of variation and CV(b) is the between-laboratory coefficient of variation) with no apparent differences between the 'in-house' and 'optimal' extraction protocols. For vitamin B-1 microbiological results tended to be higher (e.g. ca 20-50%) than HPLC results. Some further improvement could result from optimalization (i.e. lowering) of the sample-enzyme ratio. Enzyme efficiency needs to be checked with each new batch of enzyme. For vitamin B-6 results were much more at variance (CV(w) = 6-13%, CV(b) = 36-63%), especially with the pig's liver. Some discrepancy was found between laboratories using dilute mineralic acid for extraction without enzyme treatment and those using trichloroacetic acid (TCA) and/or included takadiastase treatment. It is concluded that for vitamin B-6 further standardization and method improvement is needed in order to obtain acceptable variation between laboratories. In particular, B-6 vitamer interconversion during extraction and peak interference needs further study.

A postal questionnaire survey was carried out in Dutch agriculture to identify high risk branches with respect to musculoskeletal symptoms and workload. The study population comprised a sample 2580 male employees and employers, with a response rate of 49%. A total of 75% of the employees and 71% of the employers reported musculoskeletal symptoms during the past 12 months. Low-back pain was most prevalent (one-year prevalence rate of 51% among employees, 47% among employers), followed by symptoms of the neck-shoulder (one-year prevalence rate of 35% among employees, 30% among employers) and knees (one-year prevalence rate of 22% among employees, 17% among employers). There were marked differences between specific branches in the size and nature of musculoskeletal morbidity as well as in self-reported musculoskeletal workload. In particular protective vegetables growing and arboriculture showed both relatively high rates of symptoms and relatively high exposure levels. The results of this study were used to decide which agricultural branches and workload factors should have priority in the ergonomic interventions that followed.

Refined vegetable oils including refined peanut oil are widely used in foods. Due to shared production processes, refined non-peanut vegetable oils can contain residual peanut proteins. We estimated the predicted number of allergic reactions to residual peanut proteins using probabilistic risk assessment applied to several scenarios involving food products made with vegetable oils. Variables considered were: a) the estimated production scale of refined peanut oil, b) estimated cross-contact between refined vegetable oils during production, c) the proportion of fat in representative food products and d) the peanut protein concentration in refined peanut oil. For all products examined the predicted risk of objective allergic reactions in peanut-allergic users of the food products was extremely low. The number of predicted reactions ranged depending on the model from a high of 3 per 1000 eating occasions (Weibull) to no reactions (LogNormal). Significantly, all reactions were predicted for allergen intakes well below the amounts reported for the most sensitive individual described in the clinical literature. We conclude that the health risk from cross-contact between vegetable oils and refined peanut oil is negligible. None of the food products would warrant precautionary labelling for peanut according to the VITAL® programme of the Allergen Bureau. © 2017 Elsevier Ltd

Background: Elevated blood pressure (BP), which is a major risk factor for cardiovascular disease, is highly prevalent worldwide. Recently, interest has grown in the role of dietary protein in human BP. We performed a systematic review of all published scientific literature on dietary protein, including protein from various sources, in relation to human BP. Methodology/Principal Findings: We performed a MEDLINE search and a manual search to identify English language studies on the association between protein and blood pressure, published before June 2010. A total of 46 papers met the inclusion criteria. Most observational studies showed no association or an inverse association between total dietary protein and BP or incident hypertension. Results of biomarker studies and randomized controlled trials indicated a beneficial effect of protein on BP. This beneficial effect may be mainly driven by plant protein, according to results in observational studies. Data on protein from specific sources (e.g. from fish, dairy, grain, soy, and nut) were scarce. There was some evidence that BP in people with elevated BP and/or older age could be more sensitive to dietary protein. Conclusions/Significance: In conclusion, evidence suggests a small beneficial effect of protein on BP, especially for plant protein. A blood pressure lowering effect of protein may have important public health implications. However, this warrants further investigation in randomized controlled trials. Furthermore, more data are needed on protein from specific sources in relation to BP, and on the protein-BP relation in population subgroups. © 2010 Altorf - van der Kuil et al.

BACKGROUND. To the authors' knowledge, only a few prospective studies to date have investigated the correlation between vegetable and fruit consumption and the risk of ovarian carcinoma and their results have been inconclusive. METHODS. Vegetable and fruit intake was assessed in relation to ovarian carcinoma, among 62,573 postmenopausal women participating in The Netherlands Cohort Study on Diet and Cancer. Women reported on dietary habits and on other risk factors for cancer in a self-administered questionnaire in 1986. Follow-up of cancer was implemented by annual record linkage with The Netherlands Cancer Registry and a pathology register. After 11.3 years of follow-up, data regarding 252 incident invasive epithelial ovarian carcinoma cases and of 2216 subcohort members were available for case-cohort analyses. RESULTS. Multivariable-adjusted rate ratios (RR) of ovarian carcinoma for women in the highest compared with the lowest quintile of intake (RRQ5 vs. Q1) were 0.98 (95% confidence interval [95% CI], 0.61-1.58) for total vegetables and 1.11 (95% CI, 0.70-1.78) for total fruit. The RRQ5 vs. Q1 values of ovarian carcinoma with intake of cooked vegetables, raw vegetables, brassicas, legumes, cooked leafy vegetables, and raw leafy vegetables were 1.35 (95% CI, 0.83-2.21), 0.75 (95% CI, 0.48-1.18), 1.42 (95% CI, 0.88-2.29), 0.93 (95% CI, 0.60-1.44), 1.05 (95% CI, 0.66-1.67), and 1.23 (95% CI, 0.75-2.02), respectively. With the exception of raw endive (multivariable-adjusted RR, 0.24; 95% CI, 0.07-0.78), none of the individual vegetable or fruit items showed a statistically significant association with ovarian carcinoma. CONCLUSIONS. The results of the current study did not support a significant association between vegetable or fruit consumption and ovarian carcinoma risk in a cohort of postmenopausal women. © 2005 American Cancer Society.

Objective: To study differences in dietary intake between adults with different socioeconomic status (SES) and trends over time. Design: Cross-sectional study based on data of three Dutch National Food Consumption Surveys (DNFCS-1 1987/88; DNFCS-2 1992; DNFCS-3 1997/98), obtained from a panel by a stratified probability sample of the non-institutionalized Dutch population. Subjects: A total of 6008 men and 6957 women aged 19 y and over. Methods: Dietary intake was assessed with a 2 day dietary record. Background information was obtained by structured questionnaire. Sociodemographic variables were available from panel information. SES, based on educational level, occupation and occupational position was categorized into (very) low, middle and high. Analysis of variance with age as covariable was used to explore the effects of SES on dietary intake and anthropometry. Statistical tests for trend were carried out with models in which week-weekend-day effects and an interaction term of time with SES were also included. Results: The prevalence of obesity and skipping of breakfast was higher among people with a low SES. In all three surveys, subjects in the (very) low SES group reported having a higher consumption of potatoes, meat and meat products, visible fats, coffee and soft drinks (men only). Subjects with a high SES reported consuming more vegetables, cheese and alcohol. As regards nutrients, in all surveys a higher SES was associated with higher intake of vegetable protein, dietary fibre and most micronutrients. A higher SES was also associated with a lower fat intake but the differences between social classes were rather small and not consistent when the contribution of alcohol to energy intake was taken into account. Conclusion: In general, dietary intake among subjects in higher SES groups tended to be closer to the recommendations of the Netherlands Food and Nutrition Council and this phenomenon was quite stable over a period of 10y.

Twelve mercapturic acids derived from saturated and unsaturated aliphatic and aromatic isothiocyanates were synthesised, by adding isothiocyanate to a solution of N-acetyl-L-cysteine and sodium bicarbonate, in a typical yield of 77%. Isothiocyanates were synthesised first by adding the corresponding alkyl bromide to phthalimide potassium salt. The obtained N-alkyl-phthalimide was hydrazinolysed yielding the alkyl amine, which subsequently was reacted with thiophosgene yielding the isothiocyanate with an overall yield of 16%. Mercapturic acids in urine can serve as a biomarker of intake to determine the health promoting potential of isothiocyanates present in cruciferous vegetables. © 2003 Éditions scientifiques et médicales Elsevier SAS. All rights reserved.

In 1989, the Community Bureau of Reference started a research program to improve the quality of vitamin analysis in food. To achieve this task, vitamin methodology was evaluated and tested by interlaboratory studies and the preparation of certified reference materials, which will be used for quality control of vitamin measurements. The main improvements in methodology were achieved by testing and standardizing the extraction condition and enzymatic hydrolysis procedures. Results for each individual material are derived from five replicate determinations using at least two independent methods: Liquid chromatography (HPLC) and microbiological assay for vitamins B1, B2, and B6; and radioprotein binding and microbiological assays for vitamin B12. The certificate of analysis for four reference materials gives mass fraction values for water-soluble vitamins. These certified values were based on the acceptable statistical agreement of results from collaborating laboratories. Certified values with uncertainties (mg/kg dry matter) for each CRM are as follows: 4.63 (0.20) and 4.10 (0.51) for vitamins B1 and B6, respectively, in CRM 121 (wholemeal flour); 6.51 (0.24), 14.54 (0.3), 6.66 (0.43), and 0.034 (0.003) for vitamins B1, B2, B6, and B12, respectively, in CRM 421 (milk powder); 3.07 (0.17) and 4.80 (0.40) for vitamins B1 and B6, respectively, in CRM 485 (lyophilized mixed vegetables), and 8.58 (0.55), 106.8 (2.8), 19.3 (1.5), and 1.12 (0.044) for vitamins B1, B2, B6, and B12, respectively, in CRM 487 (lyophilized pig liver).

Humans are frequently exposed to Listeria monocytogenes, and high numbers may be ingested during consumption of certain types of food. However, epidemiological investigations show that listeriosis is a rare disease. Risk assessment studies using an animal mouse model indicate that almost all L. monocytogenes serovars present in food have clear virulent properties. The intravenous dose causing infection in 50% (IV ID50) of mice not previously exposed to L. monocytogenes (nonprotected mice) was 1.8 log10 units. For mice previously exposed to L, monocytogenes (immunologically protected mice), the IV ID50 was 5.6 log10 units. The ID50 of orally exposed nonprotected mice amounted to 6.5 log10 units, and no significant effects of type of food (water/milk) and storage time at 5°C (milk) were observed. The oral ID50 of immunologically protected mice was >9.0 log10 units. Furthermore, there was approximately 1-2 log10 difference between the ID10 and the lethal dose causing death in 50% (LD50). The results show that both the intestinal barrier and the specific immune defense mechanism are highly effective in preventing infection of mice orally exposed to L. monocytogenes. Delaying the immune defense had no effect on the protective activity of the intestinal barrier, indicating that these protective mechanisms operate independently. The risk assessment results obtained in the mouse model support the epidemiological finding that listeriosis is a rare disease in humans, despite frequent exposure to the organism.

The relation between vegetable and fruit consumption and colorectal cancer risk was comprehensively assessed in the Netherlands Cohort Study on Diet and Cancer using a validated 150-item food frequency questionnaire. After 6.3 years of follow-up (1986-1992), over 1,000 incident cases of colorectal cancer were registered. Using case-cohort analysis, the authors calculated rate ratios and 95% confidence intervals adjusted for age, alcohol intake, and family history of colorectal cancer. For colon cancer, no statistically significant associations with total vegetable intake or total fruit intake were found. However, among women, an inverse association was observed with vegetables and fruits combined (for the highest quintile vs. the lowest, the rate ratio was 0.66 (95% confidence interval: 0.44, 1.01)). Brassica vegetables and cooked leafy vegetables showed inverse associations for both men and women. Among women and, to a lesser extent, among men, inverse associations were stronger for distal colonic tumors than for proximal colonic tumors. For rectal cancer, no statistically significant associations were found for vegetable consumption or fruit consumption or for specific groups of vegetables and fruits; only Brassica vegetables showed a positive association in women. As in other cohort studies, the observed inverse relation between vegetable and fruit consumption and occurrence of colorectal cancer was less strong than relations reported in case-control studies.