Cyanide detoxification in cassava for food and feed uses

Cassava (Manihot esculenta Crantz) is an important tropical root crop providing energy to about 500 million people. The presence of the two cyanogenic glycosides, linamarin and lotaustralin, in cassava is a major factor limiting its use as food or feed. Traditional processing techniques practiced in cassava production are known to reduce cyanide in tubers and leaves. Drying is the most ubiquitous processing operation in many tropical countries. Sun drying eliminates more cyanide than oven drying because of the prolonged contact time between linamarase and the glucosides in sun drying. Soaking followed by boiling is better than soaking or boiling alone in removing cyanide. Traditional African food products such as gari and fufu are made by a series of operations such as grating, dewatering, fermenting, and roasting. During the various stages of gari manufacture, 80 to 95% cyanide loss occurs. The best processing method for the use of cassava leaves as human food is pounding the leaves and cooking the mash in water. Fermentation, boiling, and ensiling are efficient techniques for removing cyanide from cassava peels.     

Processing factors affecting the level of residual cyanohydrins in gari

Intake of cyanogens in gari, a food processed from cassava roots, is implicated in the causation of tropical ataxic neuropathy (TAN). This neurological syndrome is endemic in some communities in south‐western Nigeria. Studies have shown that methods of processing cassava roots determine the quantity of cyanogens in gari. This study was conducted to investigate the effects of the method of dewatering and the duration of fermentation on cyanogens in gari. Cassava roots (400 kg) were peeled, washed, grated and divided into 14 woven polyethylene sacks. The mash in seven of the sacks was dewatered continuously during fermentation, while the mash in the remaining seven sacks was fermented without dewatering, but dewatered at the end of fermentation. Cassava mash from each treatment was roasted into gari at 24 h intervals up to 168 h. Mean cyanohydrin content in gari roasted from cassava mash dewatered continuously during fermentation was 10.8 mg HCN eq kg^?1 dw (CI 9.7–11.9), while mean cyanohydrin content in gari roasted from cassava mash dewatered after fermentation was 6.3 mg HCN eq kg^?1 dw (CI 5.3–7.4). Mean linamarin content was 4.0 mg HCN eq kg^?1 dw (CI 3.1–4.9) and mean HCN content was 1.6 mg kg^?1 dw (CI 1.3–1.9) in gari roasted from cassava mash dewatered continuously, while mean linamarin content was 3.2 mg HCN eq kg^?1 dw (CI 2.3–4.0) and mean HCN content was 1.2 mg kg^?1 dw (CI 0.9–1.5) in gari roasted from cassava mash dewatered after fermentation. The method of dewatering cassava mash and the duration of fermentation were significantly associated with the level of cyanohydrin in gari (p < 0.001). This study shows that dewatering of cassava mash continuously during fermentation contributes to the dietary cyanide load in TAN‐affected communities. © 2002 Society of Chemical Industry     

Cyanogenicity of cassava varieties and risk of exposure to cyanide from cassava food in Nigerian communities

BACKGROUND: High‐cyanogenic cassava varieties are cultivated in many tropical communities that are free of neurological syndromes attributed to consumption of cassava foods. This study was done in four geographical areas of Nigeria (northern, southwestern, southeastern and an area endemic for ataxic polyneuropathy) to determine if cyanogenicity of cassava is associated with geographical area, altitude or level of cyanogenic compounds in gari, a popular cassava food in West Africa. RESULTS: Mean levels of cassava cyanogens were 153, 127, 68 and 65 mg HCN equivalents (eq.) kg^?1 dry weight (DW) in the endemic, southeastern, southwestern and northern areas respectively (P < 0.0001), while mean levels of gari cyanogens were 9, 4, 7 and 13 mg HCN eq. kg^?1 DW in the respective areas (P < 0.0001). The mean altitude was 35 m in the endemic area, 55 m in the southeastern area, 220 m in the southwestern area and 273 m in the northern area (P < 0.0001). Altitude was associated with cyanogenicity of cassava in univariate and multivariate models (P < 0.0001). One hundred and twenty‐six (93%) farmers and 255 (77%) processors did not perceive cassava or its food products as toxic. CONCLUSION: The findings indicate that cyanogenicity of cassava is determined by environmental factors rather than by conscious selection of varieties by farmers. Farming high‐cyanogenic cassava is not associated with high levels of residual cyanogens in gari. Cassava is not perceived as toxic by farmers and processors. Copyright © 2008 Society of Chemical Industry     

The retail market for fresh cassava root tubers in the European Union (EU): the case of Copenhagen,Denmark — a chemical food safety issue?

BACKGROUND: A number of retail shops in Copenhagen sell fresh cassava roots. Cassava roots contain the toxic cyanogenic glucoside linamarin. A survey was made of the shop characteristics, origin of the roots, buyers, shop owner's knowledge of toxicity levels, and actual toxicity levels. RESULTS: Shops selling fresh cassava were shown mostly to be owned by persons originating in the Middle East or Afghanistan, buyers were found to predominantly be of African origin, and sellers' knowledge concerning the potential toxicity was found to be very restricted. Seventy‐six per cent of the roots purchased had a total cyanogenic potentials (CNp) above the 50 mg HCN equivalents kg^?1 dry weight (d.w.) proposed as acceptable by an EU working group. Two of 25 roots purchased had CNp higher than 340 mg HCN eq. kg^?1 d.w. CONCLUSION: The EU has previously made risk assessments concerning cassava and cyanogenic compounds. In the light of the conclusions drawn, the EU needs to make decisions about how to deal with the regulation and control of fresh cassava roots imported to the European food market. Also cassava root products and cassava leaves should be considered. Copyright © 2009 Society of Chemical Industry     

Picrate paper kits for determination of total cyanogens in cassava roots and all forms of cyanogens in cassava products

The simple semiquantitative picrate method for the determination of total cyanogens in cassava flour has been modified by increasing the concentration of the picrate solution used to make up the picrate papers, such that a linear Beer's Law relation between absorbance and cyanogen content is obtained over the range 0–800 mg HCN equivalents kg⁻¹ cassava. The method has been adapted to determine the total cyanogen content of cassava roots and the results compared using the picrate method and the acid hydrolysis method for six different roots from five cultivars. The agreement between the results is satisfactory. The simple method for determination of total cyanogens in cassava roots in the field is available in kit form. The methodology has been modified to allow determination of the three different forms of cyanogens present in cassava flour, viz HCN/CN⁻, acetone cyanohydrin and linamarin. HCN/CN⁻ is determined by the picrate method in which cassava flour is reacted with 0.1 M sulphuric acid for 3 h at room temperature. HCN/CN⁻ plus acetone cyanohydrin is also determined by the picrate method after treating cassava flour with 4.2 M guanidine hydrochloride at pH 8 for 3 h at room temperature. A comparison has been made of the amounts of the three cyanogens present in six cassava flour samples using the semiquantitative picrate and the acid hydrolysis methods. The agreement between the two methods is satisfactory, which shows that the new methodology works well. The picrate method for determination of the three cyanogens in cassava flour is also available as a kit. © 1999 Society of Chemical Industry     

Effect of two ethnic processing technologies on reduction and composition of total and non-glucosidic cyanogens in cassava

The effectiveness of two different processing methods on reduction of total and non-glucosidic cyanogens in cassava was studied in two ethnic groups in Nkhota Kota, Malawi. Cassava cyanogen content was periodically monitored during processing. Total cyanogen reductions of 97.9 ± 0.5% and 82.4 ± 1.0% were obtained upon soaking peeled and unpeeled roots, respectively. The residual cyanogen content (2.6 ± 0.7 mg HCN eq./kg) in flour produced from peeled roots was lower than the FAO/WHO limit (10 mg HCN eq./kg). The flour from the unpeeled method contained twenty times more residual cyanogen levels (53.8 ± 1.8 mg HCN eq./kg dry matter). The peels exhibited four times higher cyanohydrin than the pulp. Inclusion of the peel during processing therefore leads to high retention of cyanogens in the pulp. Clearly, soaking of peeled roots is a more effective method and thus should be promoted among ethnic communities that soak unpeeled roots.     

Rising African cassava production,diseases due to high cyanide intake and control measures

Cassava is the staple food of tropical Africa and its production, averaged over 24 countries, has increased more than threefold from 1980 to 2005, and the population has more than doubled over that time compared with a 1.5 times increase worldwide. Agriculturally, cassava performs very well but the roots and leaves contain cyanogenic glucosides that are dangerous to human health. These cyanogens sometimes produce acute intoxication leading to death, they exacerbate goitre and cretinism in iodine‐deficient regions, cause konzo and are implicated in the occurrence of tropical ataxic neuropathy and stunting of children. Konzo is an irreversible paralysis of the legs with many thousands of cases, mainly amongst children, in Mozambique, Tanzania, Democratic Republic of Congo, Cameroon, Central African Republic and probably other tropical African countries. Attempts to alleviate cassava cyanide toxicity have included the development of an information network and distribution in developing countries of picrate kits, which measure total cyanide in cassava and urinary thiocyanate. A simple wetting method that reduces total cyanide in cassava flour three‐ to sixfold has been successfully field tested and is being introduced in Mozambique. Transgenic technology shows promise in increasing the rate of loss of cyanide from roots during processing. World health and agricultural bodies should pay more attention to emerging health problems associated with toxicity of cyanogens in cassava. Copyright © 2008 Society of Chemical Industry     

A survey of total hydrocyanic acid content in ready-to-eat cassava-based chips obtained in the Australian market in 2008

Cassava (Manihot esculenta Crantz) is a widely consumed food in the tropics that naturally contains cyanogenic glycosides (cyanogens, mainly composed of linamarin, acetone cyanohydrin, and hydrocyanic acid). If cassava is not adequately processed to reduce the level of cyanogens prior to consumption, these compounds can lead to the formation of hydrocyanic acid in the gut. Exposure to hydrocyanic acid can cause symptoms ranging from vomiting and abdominal pain to coma and death. In 2008, a survey of ready-to-eat (RTE) cassava-based snack foods was undertaken to determine levels of cyanogens measured as total hydrocyanic acid. This survey was undertaken in response to the New South Wales Food Authority being alerted to the detection of elevated levels of cyanogens in an RTE cassava-based snack food. This survey took 374 samples of RTE cassava chips available in the Australian marketplace. Significant variation in the levels of total hydrocyanic acid were observed in the 317 samples testing positive for cyanogens, with levels ranging from 13 to 165 mg of HCN equivalents per kg (mean value, 64.2 mg of HCN eq/kg for positive samples). The results from this survey serve as a timely warning for manufacturers of RTE cassava chips and other cassava-based snack foods to ensure there is tight control over the levels of cyanogens in the cassava ingredient. Evidence from this survey contributed to an amendment to the Australia New Zealand Food Standards Code, which now prescribes a maximum level for hydrocyanic acid in RTE cassava chips of 10 mg of HCN eq/kg, which aligns with the Codex Alimentarius Commission international standard for edible cassava flour.     

Souring and breakdown of cyanogenic glucosides during the processing of cassava into akyeke

The population and composition of the lactic acid bacteria microbiota as well as the content of cyanogenic glucosides occurring at various stages of fermentation and subsequent processing of cassava roots into akyeke, a steamed sour cassava meal, were investigated. The number of lactic acid bacteria and percentage titratable acidity increased during 5 days of fermentation, but decreases were observed in the subsequent operations of 'washing' the dough with water followed by partial drying and steaming. In field and laboratory samples, Lactobacillus plantarum accounted for 59.3% and 52.3%, Lactobacillus brevis 23.3% and 22.8% and Leuconostoc mesenteroides subsp. cremoris 14.5% and 15.8%, respectively, of all lactic acid bacteria isolated at various stages of fermentation and processing. A reduction of about 98% occurred in the total cyanogens (CN) content of cassava roots during processing, from 69.3 to 1.4 and 110.3 to 2.8 mg CN equivalent/kg dry weight for laboratory and field samples of akyeke, respectively.     

Cyanogen content of cassava roots and flour in Indonesia

A survey has been made of the total cyanogen content of cassava roots and products from the cassava growing provinces of Lampung and East, Central and West Java, in Indonesia. Twenty five samples of cassava products were analysed for cyanogens by the acid hydrolysis method and also by the simple picrate kit method. The mean percentage difference between the results was 17%. Thirty samples of cassava starch and other specialised products had a mean cyanogen content of only 5 ppm, whereas 29 samples of cassava flour, chip and gaplek gave a much higher mean cyanogen content of 54 ppm (SD 51). The WHO safe value for cassava flour is 10 ppm and the Indonesian level is 40 ppm. There are four outliers of cyanogen content 140–200 ppm, which would be dangerous to human health. The cyanogen content of starch/chips/gaplek needs to be reduced by using cultivars of lower cyanogen content and by using improved processing methods. Twenty seven samples of cassava roots gave a mean cyanogen content of 19 ppm (SD 14). ©     

Improved enzymic assay for cyanogens in fresh and processed cassava

The assay for cassava cyanogens developed at the Natural Resources Institute has been modified to overcome some of the problems encountered when the assay is applied to cassava products. Inclusion of 25% ethanol in the extraction medium increased the volume of recovered extract from heat-processed cassava products, eliminated the need for centrifugation and did not interfere with any aspect of the assay. Greater cyanohydrin recovery was noted and the calculation for cyanogen contents was changed to take into account the total extract volume. The separate assay of the three cyanogens (glucosides, cyanohydrins and free cyanide) was achieved by buffering aliquots of the extract followed by appropriate treatment. The importance of assaying for free cyanide (HCN) at pH 4 was demonstrated. Above this pH, cyanohydrin degradation also produces free cyanide, giving rise to misleading values. The efficiency of the extraction medium in recovering added linamarin and cyanohydrin from cassava foods was determined. Recoveries of cyanohydrin were improved using the ethanol/acid medium. The stability of the cyanogens in the ethanol/acid extraction medium was tested at ambient and refrigeration temperatures. Over a two-month period, refrigerated extracts showed acceptable variation as compared with normal variation within the assay (5%) for total and non-glycosidic cyanogens but the levels of free cyanide showed heavy losses (15–56% lost). Since the relative toxicities of the three cyanogens have yet to be ascertained, the relative amount of each cyanogen may be important when assessing the safety of cassava products.     

Transformation and Balance of Cyanogenic Compounds in the Cassava Starch Manufacturing Process

The balance of total cyanogenic compounds and distribution of each compound including bound cyanide, cyanohydrin and free cyanide were evaluated in a cassava starch factory, having a production capacity around 100 t starch per day. The production of starch began with transferring washed roots to the rasper, followed by a series of extractors, separators, dewatering centrifuge and flash dryer, with an average water consumption of 11.4 t per ton dry starch. The total amount of cyanogenic compounds entering the process varied from 28 to 43 kg HCN equivalent per day, depending on the root quality. In roots, 64% of bound cyanide was primarily found and it significantly decreased to 22% after rasping whereas the cyanohydrin content increased from 34% to 62%. Most of cyanogenic compounds, predominantly present as cyanohydrin (55 to 70%), was discharged in liquid and solid wastes, accounting for 92% and 5% of total cyanide in roots, respectively. Only a negligible amount of cyanogenic compounds remained in the starch products, having less than 2 mg HCN equivalent per kilogram dry starch. Typically, water from the separators with 91% total cyanide content was recycled to the root washer before being discharged as wastewater, whereas the liquid from the coarse extractor (43% of total cyanide) was recycled to the rasper. This could cause the accumulation of cyanogen in the process and, therefore, in the finished products. With knowledge of the balance and transformation of cyanogens in starch processing, it is possible to assure the quality of low‐cyanide starch by modifying starch process features such as water circulation and pH adjustment.     

Nutritional Value of Cassava for Use as a Staple Food and Recent Advances for Improvement

ABSTRACT: Cassava is a drought‐tolerant, staple food crop grown in tropical and subtropical areas where many people are afflicted with undernutrition, making it a potentially valuable food source for developing countries. Cassava roots are a good source of energy while the leaves provide protein, vitamins, and minerals. However, cassava roots and leaves are deficient in sulfur‐containing amino acids (methionine and cysteine) and some nutrients are not optimally distributed within the plant. Cassava also contains antinutrients that can have either positive or adverse effects on health depending upon the amount ingested. Although some of these compounds act as antioxidants and anticarcinogens, they can interfere with nutrient absorption and utilization and may have toxic side effects. Efforts to add nutritional value to cassava (biofortification) by increasing the contents of protein, minerals, starch, and β‐carotene are underway. The transfer of a 284 bp synthetic gene coding for a storage protein rich in essential amino acids and the crossbreeding of wild‐type cassava varieties with Manihot dichotoma or Manihot oligantha have shown promising results regarding cassava protein content. Enhancing ADP glucose pyrophosphorylase activity in cassava roots or adding amylase to cassava gruels increases cassava energy density. Moreover, carotenoid‐rich yellow and orange cassava may be a foodstuff for delivering provitamin A to vitamin A–depleted populations. Researchers are currently investigating the effects of cassava processing techniques on carotenoid stability and isomerization, as well as the vitamin A value of different varieties of cassava. Biofortified cassava could alleviate some aspects of food insecurity in developing countries if widely adopted.     

An efficient treatment for detoxification process of cassava starch by plant cell wall-degrading enzymes

The objective of this work was to remove linamarin in starch from cassava (Manihot esculenta Crantz cv. KU-50) roots, a high-cyanogen variety by using plant cell wall-degrading enzymes, xylanase and cellulase. The combination of xylanase from Bacillus firmus K-1 and xylanase and cellulase from Paenibacillus curdlanolyticus B-6 at the ratio of 1:9 showed the maximum synergism at 1.8 times for hydrolyzing cassava cortex cell walls and releasing linamarase. Combined enzyme treatment enhanced linamarin liberation from the parenchyma by 90%. In addition, when the combined enzymes were applied for detoxification during cassava starch production, a low-cyanide-product was obtained with decreased linamarin concentration (96%) compared to non-enzyme treated tissues. Based on these results, xylanase and cellulase treatment is a good method for low-cyanide-cassava starch production and could be applied for detoxification of cassava products during processing.     

Mild methods of processing cassava leaves to remove cyanogens and conserve key nutrients

Current methods for processing cassava leaves to remove cyanogens involve pounding followed by boiling in water or boiling intact leaves for 30 min or longer. Boiling in water rapidly removes cyanogens but also breaks down vitamins, proteins and S-containing amino acids, which are necessary to detoxify ingested cyanide. Two methods have been developed to remove cyanogens whilst conserving these key nutrients present in cassava leaves. The first method involves pounding leaves in a pestle and mortar for a minimum of 10 min until the leaves are well macerated, followed by washing the pounded leaves twice in twice their weight of water at ambient temperature, which reduces the total cyanide remaining to 8%. Two further washes reduce the total cyanide to 3%. The second method is to immerse cassava leaves in ten times their weight of water at 50 ± 3 °C for 2 h followed by one change of water and further immersion for 2 h at 50 °C which reduces the total cyanide remaining to 7%.     

食用木薯块根及其制品中生氰糖苷检测方法的建立与应用

生氰糖苷含量的高低对评估食用木薯块根及其制品的食用安全性及其重要。以木薯块根和木薯粉为试材,本研究建立了亚麻苦苷和百脉根苷2种生氰糖苷（Cyanogenic Glycosides,CNGs）的快速提取和高效液相色谱-蒸发光散射（HPLC-ELSD）检测的方法,分析了不同品种木薯块根、木薯粉及其制品中CNGs含量变化。结果表明,食用木薯块根及木薯粉中CNGs提取最佳的硫酸溶液浓度分别为0.025和0.100 mol/L;HPLC-ELSD检测方法可有效分离亚麻苦苷和百脉根苷,其浓度在4.1～820.0 mg/L和2.5～250.0 mg/L范围内线性相关性较好,相关系数（r）分别达到了0.9996和0.9993,检测限（LOD）分别为2.1和0.5 mg/kg,定量限（LOQ）分别为8.2和2.0 mg/kg;该方法重复性和样品稳定性的标准偏差（RSD）都低于5.0%;木薯块根和木薯粉中2种CNGs的平均加标回收率分别在89.3%～96.3%和107.5%～114.9%之间,重复间RSD小于3.4%。样品验证结果表明:不同的木薯品种CNGs含量差异较大;种植8～9个月的木薯制备木薯粉CNGs含量较低;蒸煮加工方式可有效清除木薯食品中CNGs。本方法操作简单、稳定性较好、准确度高,在食用木薯块根及其制品中CNGs的分析与评价等研究方面具有较强的应用前景。     

Amino acid profiles and protein quality of cooked cassava leaves or ‘saka‐saka’

Cassava (Manihot esculenta Crantz) leaves form the main source of protein in a diet consisting of processed cassava roots as sole staple food in konzo‐affected areas of the Democratic Republic of Congo. Pounded cassava leaves were hydrolysed and analysed by HPLC before and after cooking to assess amino acid profiles and protein quality. An average of about 58% loss of total protein content was observed in five different cooked samples. The protein content in cassava leaves was high, an average of 285.9 g kg^?1 dry weight in the raw and 119.2 g kg^?1 dry weight in the cooked samples, but of poor quality, with sulphur amino acids as the most limiting amino acids. Lysine and leucine were also limiting amino acids in some of the raw samples. Lysine, histidine, leucine and isoleucine were limiting amino acids in the cooked samples besides the sulphur amino acids. The consumption of cassava leaves does not compensate the dietary deficiency of sulphur amino acids in the roots that are the staple food in konzo‐affected areas. Sulphur amino acids are essential for detoxification of the residual cyanogens remaining in insufficiently processed cassava roots. Cereals and legumes, as sources of sulphur amino acids and lysine respectively, should be promoted as part of the diet in those areas to prevent the paralytic neuro‐toxico‐nutritional disease konzo among the poor population. Copyright © 2003 Society of Chemical Industry     

Mechanism of cyanogen reduction in cassava roots during cooking

The cyanogen elimination profile during cooking of cassava roots was investigated and correlated with the changes in cyanogenic β-glucosidase (GLase) activity monitored at close intervals in the cook water and root. Cyanogenic β-glucosidase (GLase) activity was detected in the cook water within 5 min of starting cooking. Whilst significant decrease in the GLase activity was noticed in cook water and root within 15 and 10 min, respectively, for varieties M4 and H165, H1687 GLase activity decreased tremendously only at 20 and 15 min in the cook water and root, respectively. There was no GLase activity in cook water after the 30 min pre-boiling phase while GLase activity was present in the roots even after 60 min of cooking. The decrease in GLase activity at 15–20 min pre-boiling phase led to accumulation of cyanogens in cook water. The cyanogen fractions (glucosidic and non-glucosidic) increased significantly with cooking in the cook water in the case of varieties M4 and H165 while their levels were almost static throughout the post-boiling phase for H1687. The amount of HCN escaping through steam did not bear a direct relationship with the initial cyanogen content in cassava roots. Although free cyanogen is highly volatile, all of it does not escape through steam and a certain quantity appears to be stabilised in the cook water. ©1997 SCI     

Starch determination,amylose content and susceptibility to in vitro amylolysis in flours from the roots of 25 cassava varieties

BACKGROUND: Cassava cultivars are classified following different criteria, such as cyanogenic glucoside content or starch content. Here, flours from the roots of 25 cassava varieties cultivated simultaneously in a single plantation, were characterized in terms of starch content (SC), amylose content (AC), α‐amylolysis index (AI) and gel formation ability. Resistant starch content (RS) was measured in 10 of the samples. RESULTS: Cassava flours exhibited high SC, low AC and low AI values, with differences among varieties. Cluster analysis based on these parameters divided the cultivars in four groups differing mainly in SC and AC. AI and AC were inversely correlated (r = ? 0.59, P < 0.05) in 18 of the cultivars, suggesting AC as an important factor governing the susceptibility to enzymatic hydrolysis of starch in raw cassava. Differences in susceptibility to amylolysis, assessed by RS, were also recorded in the sample subset analyzed. Most flours yielded pastes or gels upon heating and cooling. Gels differed in their subjective grade of firmness, but none exhibited syneresis, confirming the low retrogradation proclivity of cassava starch. CONCLUSION: Some differences were found among cassava samples, which may be ascribed to inter‐cultivar variation. This information may have application in further agronomic studies or for developing industrial uses for this crop. Copyright © 2011 Society of Chemical Industry     

Retention of carotenoids in cassava roots submitted to different processing methods

Large genetic variation in carotenoid content has been reported after screening roots from thousands of cassava genotypes. Moreover, these pigments have to withstand different processing methods before cassava is consumed. True retention of β‐carotene from cassava roots that had been boiled, oven‐dried, sun‐dried, shadow‐dried, or used for gari preparation was measured. True retention was also measured after storing for 2 or 4 weeks some of the products of these processing methods. Oven‐drying, shadow drying and boiling retained the highest levels of β‐carotene (71.9, 59.2 and 55.7%, respectively) and gari the lowest (about 34.1%). Higher retention was observed when dried roots were kept as chips rather than as flour. Storage of flour packed in plastic bags under vacuum unexpectedly resulted in higher losses than storage of flour packed in plastic bags without the application of vacuum. Losses were higher during the first 2 weeks and tended to be considerably lower during the second 2 weeks of storage. Copyright © 2006 Society of Chemical Industry