Volume 1 Number 2 2007: Special Issue

Issue Information [PDF]

CONTENTS AND ABSTRACTS

SPECIAL SECTION: Natural Biological Compounds and Food Preservation

Guest Editor: Noureddine Benkeblia, Rakuno University, Japan

Iraj Rasooli (Iran) Food Preservation - A Biopreservative Approach (pp 111-136)

Full Text [PDF]

Invited Review: Preservative agents are required to ensure that manufactured foods remain safe and unspoiled. Antimicrobial properties of essential oils (EOs) reveal that Gram-positive bacteria are more vulnerable than Gram-negative bacteria. A number of EO components have been identified as effective antibacterials, e.g. carvacrol, thymol, eugenol, cinnamaldehyde and cinnamic acid, having minimum inhibitory concentrations (MICs) at higher dilutions in vitro. EOs comprise a large number of components and it is likely that their mode of action involves several targets in the bacterial cell. The potency of naturally occurring antimicrobial agents or extracts from plants, ranges of microbial susceptibility and factors influencing antimicrobial action and their antioxidative properties, aimed at food preservation, are reviewed in this article. Methods employed for estimation of inhibitory activity, mode of action and synergistic and antagonistic effects are evaluated. The potential value of these agents as natural and biological preservatives is considered.

Dominic K. Bagenda, Koji Yamazaki (Japan) Application of Bacteriocins in Food Preservation and Safety (pp 137-148)

Full Text [PDF]

Invited Review: Recent developments in the application of bacteriocin-producing bacteria to preserve food and maintain its safety are reviewed. The aim is to create a comprehensive compilation of advances in the applications of bacteriocins or the bacteria that produce them. Bacteria reviewed possess genetic mechanisms to produce, modify and export bacteriocins as well as genetic mechanisms to avoid self destruction by the bacteriocins produced. The actual role of these mechanisms in nature remains unclear. It is hypothesized that there is competitive advantage over bacteria that do not produce bacteriocins, but this has not been convincingly demonstrated. Nevertheless food grade bacteria possessing these mechanisms have been used in food to improve safety and extend shelf life. Driven by increasing consumer demand for more natural yet safer food, research on bacteriocins has yielded several bacteriocins and innovated commercial applications for them. Success in bacteriocin research has initiated commercial, regulatory and consumer acceptance similar or in some cases superior to that of chemical food preservatives currently in use.

Nedyalka V. Yanishlieva-Maslarova, Emma M. Marinova (Bulgaria) Activity of Natural Antioxidants on Lipids (pp 149-160)

Full Text [PDF]

Invited Review: The kinetic behaviour of derivatives of benzoic and cinnamic acids, -tocopherol, ascorbyl palmitate, flavonoids, coumarins, carnosol, thymol, carvacrol, resveratrol and carotenoids in lipid oxidation were studied. Most of the experiments were carried out with kinetically pure triacylglycerols or methyl esters of fatty acids. Some of the investigations were performed with fats and oils without purification in view to get information for the practice concerning the possibility for stabilization of real lipid systems. A new general parameter, activity A, for complex estimation of the effect of the antioxidants in lipids is proposed. It unifies the effectiveness of an inhibitor in termination of the autoxidation chain, on the one hand, and its ability to change the oxidation rate during the induction period, on the other. The analysis of the kinetic data obtained allowed the participation of the antioxidants in the side reactions of inhibited oxidation to be discussed. The extracts of different Bulgarian plant materials with solvents of various polarity were studied: leaves from Rosemary officinalis L., bark from Fraxinus ornus L., selected spieces of the family Lamiaceae, used as spices in Bulgaria, e.g. Melissa officinalis L., Menta piperita L., Menta spicata L., Ocimum basilicum L., Origanum vulgare L., and Saturejae hortensis L. Propolis, algae Scenedesmus acutus, Silibum marianum seed oil, Capsicum annum L. were also examined. The participation of carotenoids in the oxidation process differs from that of phenolic antioxidants. Our study on sunflower oil oxidation showed that in an antioxidant-free lipid system, the presence of carotenoids did not show any antioxidative protection, whereas in the presence of tocopherols and under light a synergism occurred.

Guillaume G. Nicolas, Marilaine Mota-Meira, Gisèle LaPointe (Canada), Marc C. Lavoie (Barbados/Canada) Mutacins and their Potential Use in Food Preservation (pp 161-171)

Full Text [PDF]

Invited Review: Mutacins are proteinaceous antibacterial substances produced by Streptococcus mutans, an indigenous bacterial inhabitant of the oral cavity. The metabolism of S. mutans is similar to that of lactic acid bacteria (LAB) used in fermented food. Actually, only a few well-studied mutacins have been described. Mutacins B-Ny266, B-JH1140, I, III, and K8 are linear lantibiotics.  Mutacins II and H-29B are globular lantibiotics. Mutacins GS-5/Smb and BHT-Aab are dipeptide lantibiotics. Mutacins N and BHT-B are non-lantibiotic peptides while mutacin IV is a non-lantibiotic dipeptide. Some of these mutacins are active against most Gram-positive foodborne pathogens. Nisin is actually the only lantibiotic bacteriocin used as a food additive and pediocin-like bacteriocins are considered to be next in line if more antibacterial proteins are to be approved in the future. However nisin- and pediocin-resistant mutants appear relatively easily while resistant mutants against mutacins B-JH1140 and B-Ny266 could not be obtained. Mutacins thus have potential for controlling foodborne pathogens and spoilage bacteria. New methods for producing and purifying these small peptides will contribute towards developing food grade antimicrobials for use in food products. More research is needed on the applications of bacteriocins in food systems.

Chandi C. Rath (India) Prospects and Challenges of Essential Oils as Natural Food Preservatives - A Review (pp 172-180)

Full Text [PDF]

Invited Mini-Review: Food is the prime requirement of all living organisms, including human beings. Storage of food items has become essential for society in order to minimize the time to obtain a particular food as well as to maintain its nutritional quality. The earliest evidence of food preservation can be traced back to post glacial era. Luis Pasteur proved for the first time that microorganisms are associated with foods and are the major cause of food spoilage, during storage. In early days people used heat, boiling, smoking, drying, salting, and other methods for food preservation. A major development in this field was noticed during the 1940s due to the availability of low cost refrigerators and freezers. During the last two to three decades fermentation as a process and fermented foods increased the shelf life of various food items and revolutionized the techniques of food preservation, too. Later on, with the advancement of food science and technology, various modern techniques such as artificial drying, vacuum packaging, irradiation, and chemical preservatives were employed for long-term storage of food. However, these physical and chemical methods have their own limitations and various side effects. Now-a-days consumers are more concerned about the synthetic, harmful chemicals used as preservatives. Hence, human civilization has renewed its interest for use of natural products, more specifically plant products in food preservation. In the present review I try to review the history and development of food preservation techniques over time. The limitations of different modern methods of food preservation are discussed briefly, leading in search of natural compounds as food preservatives. The nature, extraction, chemical composition and various biological properties of essential oils have been elucidated. Plant essential oils with antimicrobial, antioxidant and other properties makes them a suitable candidate for use in food processing as natural food preservatives.

Monique Lacroix (Canada) The Use of Essential Oils and Bacteriocins as Natural Antimicrobial and Antioxidant Compounds (pp 181-192)

Full Text [PDF]

Invited Review: Food-borne illness resulting from consumption of food contaminated with pathogenic bacteria has been of vital concern to public health. To reduce the health hazards and economic losses due to food-borne microorganisms, the use of natural products as antimicrobial compounds seem to be an interesting way to control the presence of pathogen in food. Spices are rich in phenolic compounds such as flavonoids and phenolic compounds, witch exhibit a large range of biological effects, including antimicrobial and antioxidant properties. Lactic acid bacteria (LAB) have been also used for centuries as a preservation method of food using fermentation process. Antimicrobial activities of LAB have been demonstrated in various species and their antagonist actions are demonstrated against numerous intestinal and food-borne pathogens. The preservative ability of LAB in foods is attributed to the production of anti-microbial metabolites. Bacteriocins are antimicrobial metabolites category, recognized as small peptides and designated as bacteriocins. Bacteriocins have attracted attention as potential substitutes for antibiotics to cure and/or prevent bacterial infections and are widely employed in food preservation. The inclusion of essential oils and bacteriocins in food products should lead to beneficial effects such as improved safety, quality and flavour; and potential in the biopreservation of food. This review highlights the mechanism of action of these antimicrobial and antioxidant compounds, and their application in food systems.

Noureddine Benkeblia (Japan), Virginia Lanzotti (Italy) Allium Thiosulfinates: Chemistry, Biological Properties and their Potential Utilization in Food Preservation (pp 193-201)

Full Text [PDF]

Invited Review: Onion (Allium cepa L.), garlic (Allium sativum L.) and other edible Allium are among the oldest cultivated plants, and are used for multiple purposes. They are a rich source of several phytonutrients, and recognized to have significant and wide biological activities. These biological activities are related to the thiosulfinates, volatile sulfur compounds which are responsible for the pungency of these vegetables. The thiosulfinates or alkane(ene) thial-S-oxide are formed by the action of the enzyme alliinase (E.C. 4.4.1.4) from their respective S-alk(en)yl cysteine sulfoxides. However, depending on the Allium species, and under differing conditions, thiosulfinates can decompose to form additional sulfur constituents, including diallyl, methyl allyl, and diethyl mono-, di-, tri-, tetra-, penta-, and hexasulfides, vinyldithiins, and (E)- and (Z)-ajoene. With increasing interest into the utilization of natural biologically active compounds and the development of specific packaging, mainly active packaging, the thiosulfinates aroused much interest for the improvement of shelf-life and safety of perishable foods, and their potency as food preservatives and substitutes for chemicals. This review examines the nature and the biological activities of Allium thiosulfinates and their potential values as food preservatives in food preservation and shelf-life extension.

Nikos G. Chorianopoulos, George-John E. Nychas, Serkos A. Haroutounian (Greece) Essential Oils of Lamiaceae Family Taxa as Natural Preservatives of Food Preparations (pp 202-215)

Full Text [PDF]

Invited Review: The recent negative consumer perception against artificial food preservatives has shifted the research interest towards the development of alternatives that consumers conceive as naturals. In this context, the essential oils (EOs) of Lamiaceae family taxa constitute intriguing candidates, since numerous in vitro studies have established well their bactericidal activities against common foodborne pathogens such as Bacillus cereus, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella ser. Enteritidis, Salmonella ser. Typhimurium and Staphylococcus aureus. Main components of these EOs such as carvacrol, thymol and α-terpineol, have also been identified as effective antibacterials displaying minimum inhibitory concentrations (MICs) of 0.005-0.05% v/v. Their mode of action involves several targets in bacterial cells, while their hydrophobicity permits their partition in cell membrane lipids leading to the leakage of the cell content. Thus, many of EO components have been legally registered as flavourings in the European Union and the USA. Similar experiments on food products have established the necessity of using larger amounts of EO. More specifically, studies on meat and dairy products, fisheries, vegetables, rice and fruits indicated that concentrations higher than 0.5% v/v or v/w are required in order to display a significant antibacterial effect. On the other hand, low pH, temperature and oxygen levels act synergistically promoting greatly their activity. Finally, it is feasible to eliminate the undesired organoleptic effects of EOs through the selection of the appropriate EO with regard to the preserved food.

Chandi Charan Rath, Sikha Singh, Sashikant Dash, Rabindra Kumar Mishra (India) In Vitro Vibriocidal Activity of Coriander (Coriandrum sativum L.) and Aniseed (Pimpinella anisum L.) Essential Oils (pp 216-219)

Full Text [PDF]

Short communication: Vibriocidal activity of coriander (Coriandrum sativum) and aniseed (Pimpinella anisum) essential oils are reported against Vibrio cholerae, V. cholerae O139 and V. alginolyticus by primary screening techniques through DDM. The minimum inhibitory concentrations (MIC) of coriander and aniseed oils ranged between 1.95-62.5 and 7.81-125 ?l/ml against the strains, respectively. The activity of the oils was retained, even after heating at 100°C for 1h. Vibriocidal activities reported at 4, 32 and 37°C indicate temperature-independent activity of the oils. The activities compared well with standard antibiotics (Ciprofloxacin, Polymyxin-B, Ampicillin, Erythromycin and Trimethoprim). The bactericidal activity of the two oils against V. cholerae and V. cholerae O139 speculated to be multidimensional, whereas, against V. alginolyticus could be due to cell wall and/or protein synthesis inhibition. Coriander oil revealed better vibriocidal activity in comparison to aniseed oil. Essential oils, being natural in origin, could be a novel agent of antimicrobial compounds against antibiotic-resistant vibrios.

Marina Sokovic (The Netherlands/Serbia), Petar D. Marin, Dejan Brkic (Serbia), Leo J. L. D. van Griensven (The Netherlands) Chemical Composition and Antibacterial Activity of Essential Oils of Ten Aromatic Plants Against Human Pathogenic Bacteria (pp 220-226)

Full Text [PDF]

Original research paper: The chemical composition and antibacterial activity of essential oils from 10 aromatic plants Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angustifolia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium have been determined. Antibacterial activity of these oils and their components; i.e. linalyl acetate, linalool, limonene, a-pinene, b-pinene, 1,8-cineole, camphor, carvacrol, thymol and menthol were assayed against a variety of human pathogenic bacteria. The highest and broadest activity was shown by Origanum vulgare oil. Carvacrol possessed the highest antifungal activity among the components tested.

Supayang P. Voravuthikunchai (Thailand) Family Zingiberaceae Compounds as Functional Antimicrobials, Antioxidants, and Antiradicals (pp 227-240)

Full Text [PDF]

Invited Review: Increasing numbers of reported cases of food-associated infections and health problems associated with synthetic additives have led to a growing interest by consumers in ingredients from natural sources. Some members of the family Zingiberaceae have been extensively used as a condiment for flavoring as well as traditional medicines. These include Alpinia galanga (galanga), Boesenbergia pandurata (krachai), Curcuma amada (mango ginger), Curcuma longa (turmeric), Curcuma zedoria (zedoary), Kampferia galanga (proh hom), Zingiber officinale (ginger), and Zingiber zerumbet (zerumbet ginger). Their antimicrobial activities against important foodborne pathogens including Bacillus cereus, Campylobacter jejuni, Clostridium botulinum, Clostridium perfringens, Escherichia coli, Listeria monocytogenes, Salmonella spp., Shigella spp., Staphylococcus aureus, Vibrio spp., Yersinia enterocolitica, Hepatitis A Norwalk virus, Entamoeba histolytica, and Giardia lamblia are outlined. In addition to the antimicrobial activities against a wide range of microorganisms, their antioxidant activities have been documented. The potential uses of these plant species as food preservatives are discussed.

M. Estévez, D. Morcuende, S. Ventanas, R. Cava, J. Ventanas (Spain) The Antioxidant Properties of Plant Phenolics in Liver P?t?s are Affected by the Composition of the Food Matrix (pp 241-245)

Full Text [PDF]

Short communication: The effect of plant essential oils containing phenolic diterpenes on lipid and protein oxidation and the increase of non-heme iron (NHI) during refrigeration (+4°C/90 days) of commercial liver pâtés, was studied. These results were subsequently compared to those obtained from a parallel evaluation of the same antioxidants on liver pâtés from free-range reared Iberian pigs. Liver pâtés with no added essential oil were used as controls. The effect of sage (Salvia officinalis) and rosemary (Rosmarinus officinalis) essential oils was different depending on the type of liver pâté to which they were added. In liver pâtés from industrial genotype pigs (commercial pâtés), they acted as prooxidants, significantly increasing the generation of TBA-RS whereas no effect was detected on hexanal counts, protein oxidation and NHI content. In liver pâtés from Iberian pigs, sage and rosemary essential oils successfully reduced the generation of lipid and protein oxidation products and inhibited, in addition, the release of iron from the heme molecule. The large differences between liver pâtés from Iberian and industrial genotype pigs in terms of fatty acid composition, the levels of tocopherol and the susceptibility to undergo oxidative reactions could have an influence on the activity of the plant phenolics.

Carole Tournier, Claire Sulmont-Rossé, Elisabeth Guichard (France) Flavour Perception: Aroma, Taste And Texture Interactions (pp 246-257)

Full Text [PDF]

Invited Review: Flavour perception is determinant for the acceptability of food products by consumers. Aroma and taste play an important role in flavour perception and it is well known that the chemical composition of the matrix and consequently its structure influences release and perception of flavour. However, from simultaneous measurements of human perception and physical concentration in vivo, texture - aroma and texture - taste interactions are not always explained by physico-chemical mechanisms. Moreover aroma - taste interactions have been the subject of many studies already reviewed and are mainly explained by cognitive interactions even if in some case physico-chemical mechanisms may occur. Finally, few studies mentioned the impact of aroma and taste on texture perception. The aim of this review is to focus on the impact of aroma, taste and texture interactions on flavour perception. For each type of binary interactions (texture - aroma, aroma - texture, texture - taste, taste - texture, taste - aroma and aroma - taste) we will present a short state of the art and the mechanisms that could be involved in the interactions: physico-chemical and cognitive mechanisms. The mechanisms of aroma - taste and taste ? aroma interactions are known to mainly depend on learning association. However, the mechanisms involved in texture - flavour and flavour - texture interactions are more complex and need further developments to understand the part explained by flavour partition in the product, flavour release in the mouth after food breakdown and cognitive interactions.

M. Beatriz A. Glória, Silvia M. Vieira (Brazil) Technological and Toxicological Significance of Bioactive Amines in Grapes and Wines (pp 258-270)

Full Text [PDF]

Invited Review: Bioactive amines in grapes and wines are important from both technological and toxicological points of view. Polyamines are essential for optimum grape productivity and quality. Biogenic amines can, at high amounts, cause undesirable physiological effects in sensitive individuals. They can also have a negative effect on wine flavor and aroma. Furthermore, they can be used as an index of hygienic-sanitary conditions during production. One aspiration of the wine industry is to reduce the risk of biogenic amines. Updated information is provided on the biochemical and physiological aspects of bioactive amines, their formation and roles in grape production and winemaking, as well as ways to prevent their formation and accumulation in wines.

Nigel G. Yee, William T. Bussell (New Zealand) Good Potatoes for Good Potato Crisps: A Review of Current Potato Crisp Quality Control and Manufacture (pp 271-286)

Full Text [PDF] Erratum [PDF]

Invited Review: Potato crisps are commercially manufactured by frying thin slices of potato tuber in oil/fat using automated production machinery. During the manufacturing process, the properties of the tuber are transformed to produce a potato crisp that is of a light golden complexion, mechanically crisp and palatable to consumers. This paper reviews the manufacturing process used to produce potato crisps, legislative regimes governing the production of potato crisps, and sensory methods used to determine the quality properties of the potato crisp. Measurement methods used to determine potato crisp quality and identify unsatisfactory potato crisps produced within the manufacturing process are discussed. The review concludes with a case study using near infrared spectroscopy for determination of moisture levels in potato crisps.

Chongwei Zhang, Peter Bucheli, Xinhua Liang, Yanhua Lu (China) Citrus Flavonoids as Functional Ingredients and Their Role in Traditional Chinese Medicine (pp 287-296)

Full Text [PDF]

Invited Review: Citrus flavonoid concentration in different tissues of citrus from different species around the world were compared together with citrus related traditional Chinese Medicine (TCM) ingredients. The citrus species with high flavonoid content like Citrus aurantium and the flavonoid-enriched tissues such as peel and young fruit are frequently utilized in TCM recipes for their gastric protective, antiulcer, cholesterol lowering and anti-cancer effects. Meanwhile they are commonly used as food ingredients in China. Along with the metabolism and absorption, citrus flavonoids are reviewed by their structure-activity relationships and insight is provided about how this compares with the functionalities in TCM treatments. Similar to the interaction with drug absorption, citrus flavonoid-enriched ingredients in TCM recipes usually contribute as “helper” through protecting main active components, enhancing the absorption of the main drugs, and exerting synergistic effects in the overall prescriptions.

Diego A. Moreno, Carmen López-Berenguer, Micaela Carvajal, Cristina García-Viguera (Spain) Health Benefits of Broccoli. Influence of Pre- and Post-Harvest Factors on Bioactive Compounds (pp 297-312)

Full Text [PDF]

Invited Review: Broccoli (Brassica oleracea L. var. italica) is a well recognized health-promoting vegetable due to its high beneficial compound content. Numerous epidemiological studies indicate that Brassicas, in general, and broccoli in particular, protect humans against some diseases since they are rich sources of glucosinolates as well as possessing a high content on flavonoids, vitamins and mineral nutrients. Glucosinolates are characteristic Brassicaceae compounds that, when the tissue is damaged, are hydrolysed by myrosinase to biologically active isothiocyanates such as sulforaphane, indole-3-carbinol and phenethyl isothiocyanate, the most responsible compounds of the anticancer activity of broccoli. Also, other phytochemicals, such as phenolic compounds and vitamin C have demonstrated antioxidant activity that protect against free radicals such as reactive oxygen species in the human body so that these have also been strongly associated with a reduced risk of chronic diseases. Accordingly, many studies have been done in order to determine the different factors that could affect these bioactive compounds. These factors could be classified into pre- and post- harvest aspects. The first group implies agronomic and environmental conditions or genetic and ontogenic factors. Thus, genotype, temperature, light radiation, fertilization, irrigation water, as well as age and harvesting time are the most important pre-harvesting factors, which may affect the bioactive composition of broccoli. The post-harvest group of factors such as packaging, storage, preservation, transport, and cooking processes have been widely reviewed and thus this review is focused on the wide bioactive content of broccoli and how the pre-harvest and post-harvest factors affect these health promoting phytochemicals.

Ting Zhou, Qian Kong, Jingrong Huang, Ruitong Dai, Quanhong Li (China) Characterization of Nutritional Components and Utilization of Pumpkin (pp 313-321)

Full Text [PDF]

Invited Mini-Review: Pumpkin is a dicotyledonous seed vegetable with many nutritional components including pumpkin polysaccharides, active proteins, essential amino acids, carotenoids, minerals, among others. It has been received considerable attentions in recent years because of the nutritional and health protective value of these components. Pumpkin is a traditional vegetable in many countries and is believed to have health benefits. In the past decades, many researches have focused on scientific evaluation of the characterization of pumpkin principal nutritional components and preparation as food or medicine functional components. Pumpkin extracts used for antidiabetic, antihypertensive, antitumor, immunomodulation, antibacterial, antihy- percholesterolemia, intestinal antiparasitia, antiinflammation, and antalgic purposes have been reported. Pumpkin has tremendous potential as a raw material in the manufacture of natural health foods, but the contribution of pumpkin to minerals, vitamins and proteins in human nutrition is limited due to the presence of antinutrients which render some of the micro-nutrients and proteins unavailable for human nutrition. Although technologies such as germination and fermentation could be used to improve pumpkin’s nutritional value and reduce these anti-nutritional substances, it is still important to identify and analyze the effect of functional components and antinutrients in pumpkin for further development of pumpkin-based health foods. This review will focus on the characterization of principal nutritional components and utilization areas of pumpkin, and point out the areas of future research to elucidate mechanisms whereby these compounds can reduce disease risk.

M. Pugalenthi, V. Vadivel (India) L-Dopa (L-3,4-Dihydroxyphenylalanine): A Non-Protein Toxic Amino Acid in Mucuna pruriens Seeds (pp 322-343)

Full Text [PDF]

Invited Review: The seeds of Mucuna pruriens, a potential tropical under-utilized legume, were reported to contain high level of protein (26-30%), desirable amino acid, fatty acid and mineral composition with good nutritional properties, comparable with that of other common legumes. It is consumed as food by people living in the rural areas of India, Sri Lanka, Philippines, Nigeria, Ghana, Brazil, Malawi and other countries. L-Dopa (L-3,4-Dihyroxyphenylalanine), a non-protein phenolic amino acid, extracted from M. pruriens seeds is being used in the treatment of Parkinson’s disease. Clinical studies also proved the effectiveness of L-Dopa extracted from M. pruriens seeds in curing Parkinson’s disease over chemically synthesized L-Dopa. But, on the other hand, the pharmaceutically active factor, L-Dopa, is potentially toxic and an antinutrient compound in a nutritional point of view. It is reported to inhibit the digestibility of protein and starch in the diet and thereby reduced the growth performance of experimental animals. It has been reported to cause some serious gastrointestinal disturbances such as nausea, vomiting and anorexia and also induce favism, if consumed by humans or animals. However, in contrast, its antioxidant potential was evidenced by certain studies. Even so, many researchers are working with L-Dopa the world over in either a nutritional or clinical aspect, and there is much conflicting information on its antinutritional and toxic effects on growing animals as well as its pharmacological side effects. However there exists no summative scientific assessment to date. Hence, the present review has been emphasized to evaluate the available information regarding the L-Dopa content of M. pruriens seeds.

Ka-Soon Lee, Ji-Yong Lee, Jong-Won Lee, Eun-Mo Lee, Man-Jin Oh (Korea) Nutritional Value of Lily Scales in Lilium lancifolium and Lilium davidii (pp 344-346)

Full Text [PDF]

Short Communication: Wild lilies in Korea are classified into 2 groups (Asiatic and Martagon) and there are about 10 species. Their scales and leaves are edible ingredients that have been used since early times; however, there have been no food nutritive studies on wild lilies in Korea. So, scales of L. lancifolium (domestic wild lily in Korea) and L. davidii (Chinese edible lily) were analyzed for their use as nutritional edible wild lilies. They have a moisture content of 68.54-82.98% and are composed of 2.32-5.48% crude protein, 0.08-0.34% crude fat, 19-24% total carbohydrate and 1.15-2.58% crude ash. In particular, L. lancifolium and L. davidii were analyzed for their carbohydrate content, being composed of 5.8-6.8% starch, 6.5-8.3% free sugar and 4.7-6.8% non-starch polysaccharide. The non-starch polysaccharide was fractionated into two groups, an acidic and a neutral fraction at a 63:37 ratio by DEAE-cellulose absorption. The non-starch polysaccharides of Lilium spp. scales mainly consist of glucose, mannose and mannuronic acid. We conclude that L. lancifolium and L. davidii are worthy as nutritional edible foods because they have high polysaccharide and protein contents. Furthermore, they are easily propagated by twin-scaling, are disease-tolerant and firmly integrated into Korean economy and culture.

Donatus Ebere Okwu, Beatrice O. Orji (Nigeria) Phytochemical Composition and Nutritional Quality of Selected Tropical Edible Grains of Northern Nigeria (pp 347-353)

Full Text [PDF]

Original Research Paper: Phytochemical composition, proximate, vitamins and minerals contents of Sorghum bicolor, Pennisetum typhoides and Triticum aestivum, which are well known Nigerian food and medicinal plants were assessed with a view to establishing and understanding their nutritional values. Phytochemical studies revealed the presence of bioactive compounds comprising flavonoids (0.90 mg.100 g^-1-6.08 mg.100 g^-1), alkaloids (1.13-1.63 mg.100 g^-1), tannins (0.28-1.02 mg.100 g^-1), phenols (0.05-0.07 mg.100 g^-1) and saponins (0.09-0.20 mg.100 g^-1). The protein, carbohydrates, lipids and fiber content were 12.25-18.81%, 71.19-80.41%, 2.68-6.03% and 1.36-4.38%, respectively. The food energy content ranges from 387.54 to 411.86 cal.g^-1. The grains are rich in B-vitamins such as niacin (1.50-4.60 mg.100 g^-1), riboflavin (0.10-0.66 mg.100 g^-1) and thiamine (0.32-1.36 mg.100 g^-1) while ascorbic acid content ranges from 6.16 to 12.32 mg.100 g^-1. These grains are good sources of minerals comprising calcium (2.41-2.61 mg.100 g^-1), phosphorus (0.28-0.32 mg.100 g^-1), potassium (0.18-0.49 mg.100 g^-1), and magnesium (1.22-1.95 mg.100 g^-1). The cereals can be considered as sources of quality raw materials for food and pharmaceutical industries.

Surekha S. Puyed, Jamuna Prakash (India) Sensory and Keeping Quality of a Ready-to-Eat Snack Incorporated with Pre-treated Soy Flour (pp 354-360)

Full Text [PDF]

Original Research Paper: The objective of this study was to investigate the effect of incorporating pre-treated soy flour on fat uptake and keeping quality of a ready-to-eat wheat-based snack. Defatted soy flour was pre-treated with partial enzyme hydrolysis or thermal treatments (using microwave and dry heat) for incorporation at a 20% level to the basic product. Products prepared without defatted soy flour and with untreated soy flour served as two controls for comparison. The prepared products were analyzed for fat uptake and stored in polyethylene terephthalate (PET), metallized foil (MF), low-density polyethylene and steel containers at room temperature (27°C) in open shelves for one month to study the shelf life. One product was stored at low temperature (4°C). All products were analyzed at weekly intervals for free fatty acids (FFA), peroxide value (PV) and sensory attributes. Results indicate that incorporation of soy flour decreased fat absorption in products at varying levels ranging from 9.3% to 29.4%. The extent of reduction was highest in the product with untreated soy flour. The sensory quality of soy flour-incorporated product was comparable to the control. Pre-treatment of soy flour with enzyme trypsin lowered the sensory quality of the product, but thermal treatment improved the scores. On storage, some of the products developed an off-flavour at the end of the 2^nd week as assessed by sensory evaluation. The addition of defatted soy flour decreased FFA and PV in stored products. Among different packaging containers MF and PET were better with a lower FFA and PV.