Journal of the Science of Food and Agriculture

Kozak, Marcin; Scaman, Christine H

doi: 10.1002/jsfa.3215pmid: N/A

This paper reviews three unsupervised multivariate classification methods: principal component analysis, principal component similarity analysis and heuristic cluster analysis. The theoretical basis of each method is presented in brief, and assumptions inherent to the methods are highlighted. A literature review shows that these methods have sometimes been used inappropriately or without referencing all essential parameters. The paper also brings to the attention of the reader a relatively unknown method: probabilistic or model‐based cluster analysis. The goal of this method is to uncover the true classification of objects rather than a convenient classification provided by the other methods. For this reason it is felt that model‐based cluster analysis will have broad application in the future. Copyright © 2008 Society of Chemical Industry

Alghazeer, Rabia; Howell, Nazlin K

doi: 10.1002/jsfa.3117pmid: N/A

BACKGROUND: Aldehydes are secondary lipid oxidation products formed during processing and storage of food. 4‐Hydroxynonenal (4‐HNE) is a major toxic lipid peroxidation product which has been extensively investigated in the clinical field but less so in food products. The aim of the present study was to investigate the formation of aldehydes in stored frozen fish (Atlantic mackerel, Scomber scombrus) with and without antioxidant (green tea). RESULTS: The presence of 4‐HNE in frozen fish was detected for the first time. 4‐HNE was extracted from frozen fish and identified using high‐performance liquid chromatography and liquid chromatography/mass spectrometry. The amount of 4‐HNE increased throughout storage for 26 weeks at − 10 °C in the absence of antioxidant. A significant decrease was observed in fish samples stored at −10 °C with green tea. Minimal amounts of 4‐HNE were formed in fish stored at −80 °C. A similar increase in 4‐HNE was found for methyl linoleate and extracted fish oil exposed to UV irradiation. CONCLUSION: The toxic aldehyde 4‐HNE can be formed in badly stored frozen mackerel and is an indicator of reduced texture quality and nutritional value of fish. Addition of instant whole green tea as an antioxidant can provide a cheap and effective way of enhancing safety, especially in developing countries. Copyright © 2008 Society of Chemical Industry

Güémes‐Vera, Norma; Peña‐Bautista, Roberto J; Jiménez‐Martínez, Cristian; Dávila‐Ortiz, Gloria; Calderón‐Domínguez, Georgina

doi: 10.1002/jsfa.3152pmid: N/A

BACKGROUND: A study was done to develop procedures for detoxifying Lupinus mutabilis seeds, and decreasing or eliminating yellow colour in derivatives from them. An evaluation was done of the effect of replacement of wheat flour with the detoxified and decolorized L. mutabilis derivatives on the quality properties of three types of bread products (loaf, bun and sweet). RESULTS: Physicochemical and nutritional analyses coincided with previous reports. The Lupinus protein concentrate and isolate had lower phenolic compound and oligosaccharide concentrations than the untreated seeds. Amino acid composition was determined for wheat flour (WF), L. mutabilis defatted and detoxified flour (LF), L. mutabilis protein concentrate (LPC) and L. mutabilis protein isolate (LPI). The resulting values were used to calculate the replacement levels at which lysine content would be increased significantly in WF–lupin blends. Replacement levels were: LF (5%, 10%, 15% and 20%); LPC (2.5%, 5%, 7.5% and 10%); LPI (0.5%, 1%, 2%, 3% and 4%). CONCLUSION: The detoxifying treatments employed decreased non‐nutritional and toxic compounds present in original lupin seed. use of citric acid (1%) reduced yellow coloration in LF and LPC. Copyright © 2008 Society of Chemical Industry

Gresta, F.; Lombardo, G. M.; Siracusa, L.; Ruberto, G.

doi: 10.1002/jsfa.3177pmid: N/A

BACKGROUND: Saffron is one of the most appreciated and expensive spices known and has been used from the oldest times as a dye for fabrics, a condiment to enrich food and for medicinal purposes. The aim of this study was to evaluate the effect of crop management methods on the quantitative and qualitative characteristics of the spice in southern Italy. Two sowing times (end of July and end of August) and two corm dimensions (4 and 3 cm horizontal diameter) were evaluated. RESULTS: Flowering period and duration were not influenced by the studied factors, while early sowing time and greater corm dimension resulted in a greater number of flowers per m2, increased stigma yield and a greater total yield of replacement corms. Early sowing time also showed a significant positive influence on stigma quality measured as apocarotenoid content according to ISO guidelines. CONCLUSION: The results show that, in a Mediterranean environment, appropriate crop techniques and selection of corms can result in economic levels of production and improve the quantitative and qualitative characteristics of saffron. In fact, according to their apocarotenoid contents, samples from the early (July) and late (August) sowing times belonged to the first and second ISO categories respectively. Copyright © 2008 Society of Chemical Industry

Hiramoto, Keiichi; Imao, Mitsuko; Sato, Eisuke F; Inoue, Masayasu; Mori, Akitane

doi: 10.1002/jsfa.3190pmid: N/A

BACKGROUND: Fermented papaya preparation (FPP) from yeast fermentation of Carica papaya Linn is a natural health food that is commercially sold in Japan. A previous study revealed that FPP has antioxidant activity. However, the effect of FPP on allergic diseases remains unclear. The aim of the present work was to examine whether the oral administration of FPP to mice restrained two types of contact hypersensitivity models, FITC (Th2 type) induced ear and colon oedema, and oxazolone (Th1 type) induced ear and colon oedema. RESULTS: The sensitisation of FITC or oxazolone increased the plasma levels of IL‐10, IFN‐γ, and TNF‐α. Histological examinations revealed a marked increase of IgA, dendritic cells and inflammatory cells in the colon. When the animals were given FPP before sensitisation by FITC or oxazolone, all the events induced by either FITC or oxazolone decreased markedly. CONCLUSION: These results suggest that the oral administration of the FPP may have a therapeutic potential for the prevention of contact hypersensitive immuno‐response. Copyright © 2008 Society of Chemical Industry

Tanaka, Aki; Horiuchi, Masahiro; Umano, Katsummi; Shibamoto, Takayuki

doi: 10.1002/jsfa.3191pmid: N/A

BACKGROUND: Licorice root is one of the most widely used medicinal herbs and its medicinal properties, such as antibacterial, anti‐ulcer, anti‐tumorigenic and anti‐atherosclerotic activities, have been widely reported. However, there are only a few reports on basic chemical and biological studies of the water distilled components of licorice root. RESULTS: Chinese licorice root was water distilled and the distillate was subsequently extracted with dichloromethane. Residual aqueous solution from the extraction was fractionated using column chromatography. A total of 127 chemicals were identified in the dichloromethane extract, which inhibited hexanal oxidation by over 90% for 45 days at the level of 50 µg mL−1. A fraction eluted from the residual aqueous solution with acetone exhibited potent antioxidant activities both in a thiobarbituric acid assay and in a malonaldehyde/gas chromatography assay. The acetone fraction also exhibited strong anti‐inflammatory activity (77.9% inhibition at the level of 62 µg mL−1) in a lipoxygenenase inhibitor screening anti‐inflammatory assay. CONCLUSION: This study demonstrated the antioxidant and anti‐inflammatory activities of the water distillate obtained from Chinese licorice root. Some volatile chemicals among the many components identified in the water distillate exhibited antioxidant activity, suggesting that many medicinal compounds escape with water vapor into the ambient air during the preparation of herbal medicine. Copyright © 2008 Society of Chemical Industry

Leite, Danielle MC; de Jong, Erna V; Noreña, Caciano PZ; Brandelli, Adriano

doi: 10.1002/jsfa.3192pmid: N/A

BACKGROUND: The seeds of Araucaria angustifolia, namely pinhão, are consumed in south and southeast Brazil as flour or baked. There is relatively little information about the chemical composition and nutritional value of the seed and its flour. RESULTS: Pinhão flour was obtained by drying at constant temperature of 50 °C (PF50) or 80 °C (PF80) in a circulating air drier for 16 h, and evaluated as a feed additive for growing rats. Wistar rats were fed five experimental diets (n = 6 rats per diet) containing different protein sources: casein (diet CAS), casein supplemented with 20% (w/w) flour PF50 or PF80 (diets PF50 and PF80), casein supplemented with 20% pinhão without heat treatment (diet NPF), and a non‐protein group (diet APROT). Values for weight gain, feed ingest, protein efficiency ratio (PER) and net protein ratio (NPR) were similar for diets CAS and PF80. Lowest values for all nutritional parameters were observed for diets complemented with pinhão flour. Trypsin inhibitor activity was detected in PF50 but not in PF80. CONCLUSION: Pinhão flour heated at 80 °C for 16 h and used as supplementary in diet had the most similar results in all nutritional parameters to casein‐based diets, and can be used as a complementary source, substituting up to 20% of a high biological value protein in food formulations. Copyright © 2008 Society of Chemical Industry

Zhang, Jin; Wu, Lianghuan; Wang, Minyan

doi: 10.1002/jsfa.3194pmid: N/A

BACKGROUND: Because only grain yield has been investigated, the influence of fertilisation by N on the concentration of Fe and Zn in polished rice has been overlooked in China. So, using the rice cultivars of the indica Zhenong 952 and the japonica Bing 98110, pot experiments were conducted to investigate the amounts of N fertiliser (applied as urea at rates of 0, 0.50, 1.00 and 1.50 g N pot−1) that would lead to the optimum Fe and Zn concentrations in polished rice as well as grain yield. RESULTS: For Zhenong 952, the optimal Fe and Zn concentration as well as grain yield was attained at a N application of 1.00 g pot−1; for Bing 98110 the optimum N was 1.50 g pot−1. The ratio of Zn deposited in brown rice was about 40% of the total Zn in the plant irrespective of N application. However, Fe was only about 3%. Fe concentration in brown rice was approximately one‐half of the rice husk, one‐fifth of the peduncles, and one‐tenth of the leaves, and a little more than 1% of the root. CONCLUSION: The optimum N application, alone, on rice crops could increase Fe concentration in polished rice, but had an adverse effect for Zn. Fe appeared not to be as easily accumulated into rice seeds as was Zn. Copyright © 2008 Society of Chemical Industry

Michalak, Izabela; Chojnacka, Katarzyna

doi: 10.1002/jsfa.3195pmid: N/A

BACKGROUND: The paper discusses biosorption of microelements by a freshwater macroalga Pithophora varia Wille to produce biological feed supplement for livestock. The biomass was enriched with microelements recommended by feeding standards in a single and a multi‐metal system. RESULTS: The equilibrium of biosorption was described by using a Langmuir model and the following values of the maximum biosorption capacity in the single‐metal system were obtained: Zn(II), 61.1 mg g−1; Co(II), 52.3 mg g−1; Cu(II), 55.7 mg g−1; and Mn(II), 38.3 mg g−1. The average value of maximum biosorption capacity expressed in molar units for all the cations was equal 1.7 ± 0.2 meq g−1, suggesting chemical rather than physical biosorption. It was also found that the mechanism of biosorption was due to cation exchange of alkali and alkaline earth metals with microelements. The biomass was also enriched with microelements in multi‐metal system. The total metal ion binding capacity in the multi‐metal system was two‐fold lower than in the single‐metal system and was 0.90 meq g−1 in the preparation for laying hens and 0.95 meq g−1 in the supplement for swine. CONCLUSION: Finally, the level of supplementation of livestock feed (with enriched single‐ and multi‐metal system macroalga), to cover 25% of total requirements for microelements, according to feeding standards, was provided. Copyright © 2008 Society of Chemical Industry

Hou, Zhen‐Ping; Yin, Yu‐Long; Huang, Rui‐Lin; Li, Tie‐Jun; Hou, Rongqing; Liu, Yulan; Wu, Xin; Liu, Zhiqiang; Wang, Wence; Xiong, Hua; Wu, Guo‐yao; Tan, Liang‐xi

doi: 10.1002/jsfa.3196