Immature Beans Research Articles

Extraction of Polyphenols from Unripened Coffee (Coffea Arabica) Residues and Use as a Natural Coagulant for Removing Turbidity

The coffee agribusiness generates significant amounts of waste that becomes an environmental problem in producing countries. For example, synthetic coagulants have sustainability disadvantages. Immature coffee beans are collected together with mature beans, and their high polyphenol content makes them unsuitable for coffee production and commercialization. This paper aims to test the coagulant activity of polyphenols extracted from Coffea arabica residues in synthetic water samples to use them as raw material for producing a natural coagulant based on bioeconomy. It would thus allow immature coffee beans to recover, avoiding their inadequate disposition. An extract was obtained from residual green coffee beans using the ultrasound-assisted separation technique with a mixture of ethanol and water in a 1:1 ratio. The Folin–Ciocalteu method was applied for the total polyphenols quantification, resulting in a concentration of 73.54 ± 0.05 mg GAE (Gallic Acid Equivalent) per gram on a dry coffee basis (GAE/gDB). The synthetic water for the study was prepared with kaolin, showing initial turbidity of 520.90 ± 0.1 NTU (Nephelometric Turbidity Units). First, the effect of pH was determined on the coagulant activity at a fixed dose of polyphenols 2.6 mg GAE/L. Second, the dose and pH results were evaluated using a multilevel factorial design with 5.20, 3.90, 2.60, and 1.30 mg GAE/L doses and pH at 2.5, 3.0, 3.5, and 4.0. Third, the turbidity removal achieved was 99.94% at a dose of 3.9 ± 0.05 mg GAE/L and a pH of 2.5. Fourth, the result was compared with the turbidity removal of the aluminum sulfate dosed at a concentration of 3 mg/L on the same water type, with a pH variation between 5.5 and 8, obtaining 98.69% of turbidity removed. Finally, the research demonstrated that the polyphenols extracted from the residues of the Coffea arabica species possess a high electrochemical affinity that would allow removing turbidity by coagulation in waters at specific pH levels with similar removals to those obtained with aluminum sulfate.

Agrobiological evaluation of collection samples of soy vegetable in the Forest Steppe of Ukraine

Purpose. Agrobiological assessment of soybean varieties Glycine max var. Shirofumi on a complex of economically valuable traits for introduction in the conditions of the Forest-Steppe of Ukraine. Selection of promising breeding forms based on morpho-biological and physiological-biochemical characteristics. Methods. Field, laboratory, statistical, computatio­nal and analytical. The studies were carried out in the conditions of the educational and production department of Uman National University of Horticulture during 2020–2021, using collection varieties of different ecological and geographical origin (Ukraine, Belarus, Sweden, Japan and Russia). The cultivars were assessed according to the following parameters: plant height, leaf area, net productivity of photosynthesis and indices of individual productivity (weight of beans per plant, number of seeds in a bean, etc.), productivity of green beans and biologically mature seeds and, accordingly, quality indicators of production (dry matter, sugar and protein content). The counts were carried out in the phase of the technical ripeness of the beans. Results. The variability of the “plant height” trait of the studied varieties had an average variation – the coefficient of variation was 22%. The results showed that the standard cultivar ‘Romatnyka’ and the collection cultivars ‘Karikachi’ and ‘Astra’ belong to the semi-determinant type of growth (97–109 cm), cultivar ‘Fiskeby V’, ‘L 380-2-13’, ‘Fiskeby V-E5’, ‘SibNIISOKh 6’, ‘Sac’, ‘Vesta’ belong to the determinant type of growth. According to the number of seeds in the pod, the studied varieties were clearly divided into two groups: with two-seeded beans (varieties ‘Karikachi’, ‘Astra’, ‘L 380-2-13’) and three-seeded beans [varieties ‘Romatnyka’ (standard), ‘Fiskeby V’, ‘Vesta’, ‘SibNIISOX 6’, ‘Sac’, ‘Fiskeby V-E5’]. The maximum yield of edamame beans was produced by varieties ‘L 380-2-13’ (17.3 t/ha), ‘Vesta’ (18.8 t/ha), ‘Sac’ (19.6 t/ha), ‘Fiskeby V’ (21.4 t/ha), ‘Fiskeby V-E5’ (22.4 t/ha). A significant differentiation of soybean varieties in the biochemical composition of immature beans was revealed. The dry matter content was 22.70–31.70%. The share of protein in edamame green beans was 28.2–38.6%, in biologically mature seeds its share increased to 36.1–42.8%. Among soluble sugars, the highest concentration was noted for sucrose – 7.70–9.38 mg/100 g in dry seeds, what in average amounted to 81.6–86.2% of all sugars. The presented results provide a comprehensive assessment of breeding work on soybean varieties with a low content of oligosaccharides. Conclusions. Evaluation of collection varieties of vegetable soybeans by the variability of morphological traits and productivity made it possible to distinguish ‘Sac’ variety by a complex of valuable traits for creation of new varieties of vegetable soybeans adapted to the conditions of the Forest-Steppe of Ukraine.

Ileal digestibility of energy and amino acids in three faba bean cultivars (Vicia faba L.) planted and harvested early or late in broiler chickens

A concern of both pulse growers and poultry producers is how the timing of planting and harvesting affect the nutritional quality of faba bean for broiler chickens. To investigate, half of the seed of 2 zero-tannin cultivars (Snowbird and Snowdrop) and 1 low vicine and convicine cultivar (Fabelle) were planted at a single site either in early May and harvested in late September (EARLY) or planted in late May and harvested in late October (LATE). Diets of the 3 EARLY or LATE cultivars (95% inclusion) were fed to 756 broiler chickens (Ross 708) from d 15. Chickens were housed in 56 floor pens (13–14 birds/pen) in a 3 × 2 factorial arrangement (7 pens/diet). A nitrogen-free diet to correct for endogenous amino acid (AA) losses was fed to broilers in 14 pens from d 20. Ileal digesta was collected after euthanizing birds on day 23 or 24. Planting and harvesting LATE vs. EARLY increased the proportion of immature beans from 5 to 64% for Snowbird, 7 to 79% for Snowdrop, and 22 to 80% for Fabelle. Planting and harvesting LATE vs. EARLY increased the proportion of frost-damaged beans from 20 to 83% for Snowbird, 36 to 88% for Snowdrop, and 5 to 29% for Fabelle. Planting and harvesting LATE vs. EARLY increased (P < 0.001) apparent ileal digestibility (AID) of gross energy (GE) by 45% and standardized ileal digestibility (SID) of CP by 13%. Planting and harvesting LATE vs. EARLY increased (P < 0.001) SID of AA by 11% except Cys. Snowbird and Snowdrop had greater (P < 0.05) SID of AA by 4.5% except Thr and Trp compared with Fabelle. Fabelle had 13% greater (P < 0.001) SID of Trp compared with Snowbird or Snowdrop. Results indicate that planting and harvesting LATE vs. EARLY increased GE, CP, and AA digestibility possibly by frost interrupting bean ripening on the field. Hull tannin content may have reduced the AA digestibility of Fabelle compared with Snowbird or Snowdrop.

Feeding different cultivars and quality levels of faba bean to broiler chickens.

A concern of both pulse growers and poultry producers is how frost damage around harvest time affects the nutritional quality of faba bean for broiler chickens. To investigate, two zero-tannin cultivars (Snowbird, Snowdrop) and one low vicine and convicine cultivar (Fabelle) sourced from seed growers were spring planted 3 weeks later than recommended (mid-May) and harvested late October to purposely increase frost damage. Parent, certified seed (high quality), and harvested frost damaged beans (low quality) of the three cultivars were fed to 740 chickens housed in 64 floor pens in a 2 × 3 factorial plus control (9 pens of 11 or 12 birds per treatment). Starter (d 0 to 11), grower (d 12 to 24), and finisher (d 25 to 40) diets included 15%, 30%, and 45% faba bean in partial (starter, grower) or total replacement of soybean meal (SBM; control). Harvested Snowbird, Snowdrop, Fabelle averaged 52%, 62%, 17% blackened hull and 35%, 43%, 51% immature beans, respectively. There was a cultivar × quality interaction (P < 0.05) on daily feed disappearance (ADFI) and gain-to-feed (G:F). Broilers fed low-quality Snowdrop consumed 10 g/d more finisher and 6 g/d more feed overall than those fed low-quality Snowbird or Fabelle; broilers fed parent seed were intermediate. Feeding low-quality Fabelle resulted in best overall G:F (0.646) versus high-quality Snowbird (0.611), high-quality Fabelle (0.624), or low-quality Snowdrop (0.624). Average daily weight gain (ADG) and bird body weight (BW) at the end of each growth phase were not affected by cultivar or quality level. Controls fed SBM only grew 2.75 g/d faster overall and were 113.5 g heavier at the end of the trial than broilers fed faba bean (P < 0.05). Controls fed SBM only had 0.024 g/g better overall G:F than broilers fed faba bean (P < 0.05). Feeding low-quality beans or high-quality seed had no effect on antemortem BW, chilled carcass weight (WT), dressing percentage or yield of saleable cuts except that broilers fed Snowbird or Snowdrop had 0.8%-unit larger thighs than those fed Fabelle. Controls fed SBM only were 110 g heavier at slaughter, had 72 g heavier chilled carcass WT, and 0.5%-unit greater dressing percentage than broilers fed faba bean (P < 0.05). These results indicate that feeding frost damaged and(or) immature faba bean, to the extent observed in this trial, did not negatively affect growth performance or carcass attributes of broiler chickens compared to feeding parent, certified, high-quality seed of these cultivars.

Phenotypic variability of cowpea genotypes for immature seed harvesting

ABSTRACT Seed color, brightness and texture are important aspects for the consumption of immature beans. This study aimed to estimate the phenotypic variability among thirty cowpea genotypes for immature seed harvesting, in order to guide breeding programs. The experiment was carried out in a randomized blocks design, with three replications. The evaluated traits were immature seeds yield, pods and dry seeds production, number of immature pods, 100-immature seeds weight, immature pods length, number of seeds per immature pod, cooking time, harvesting period of immature pods, seed color, pod color, plant growth habit, opening of immature pods, seed threshing from immature pods, cultivation value and seed browning after threshing. Anova and three clustering methods were applied: UPGMA using the Jaccard coefficient of similarity; modified Tocher method based on the Gower algorithm; and k-means. All the analyses were performed based on the variable means of experiments evaluated in six environments. A statistically significant phenotypic variability was observed among all the quantitative traits. Discrepancies occurred in the accessions grouping and number of clusters. The accession BRS Acauã, in one group, and P508 and PCCR3F6L15, in other groups, showed a good quality for immature grain harvesting, were consistently grouped into different clusters and are recommended for use as parents in the development of new cultivars.

5,7,3\u02b9,4\u02b9-Tetrahydroxyflav-2-en-3-ol 3-O-glucoside, a new biosynthetic precursor of cyanidin 3-O-glucoside in the seed coat of black soybean, Glycine max

The seed coat of mature black soybean, Glycine max, accumulates a high amount of cyanidin 3-O-glucoside (Cy3G), which is the most abundant anthocyanin in nature. In the pod, it takes two months for the seed coat color change from green to black. However, immature green beans rapidly adopt a black color within one day when the shell is removed. We analyzed the components involved in the color change of the seed coat and detected a new precursor of Cy3G, namely 5,7,3ʹ,4ʹ-tetrahydroxyflav-2-en-3-ol 3-O-glucoside (2F3G). Through quantitative analysis using purified and synthetic standard compounds, it was clarified that during this rapid color change, an increase in the Cy3G content was observed along with the corresponding decrease in the 2F3G content. Chemical conversion from 2F3G to Cy3G at pH 5 with air and ferrous ion was observed. Our findings allowed us to propose a new biosynthetic pathway of Cy3G via a colorless glucosylated compound, 2F3G, which was oxidized to give Cy3G.

Impacts of quaker beans over sensory characteristics and volatile composition of specialty natural coffees

The objective of this study was to evaluate the volatile composition and the sensory effect of the presence of Quaker beans in natural specialty coffee beverage and, consequently, to confront the requirement of the Specialty Coffee Association regarding the total absence of Quaker beans in a natural specialty coffee batch. Sensory analysis and volatile composition were performed for three different colorations of Quaker beans, added separately to natural specialty coffee samples at seven different concentrations. Beans with color equal to or above Agtron 82.8 negatively affected the sensory characteristics of natural specialty coffee only from the presence of 7 Quaker beans in one cup (65 beans). Through the analysis of volatile composition, volatile compounds formed during roasting were identified in Quaker beans from precursors present in raw immature beans. Therefore, the color and sensory characteristics of Quaker are a consequence of the chemical composition of an immature bean.

Comprehensive lipid analysis of green Arabica coffee beans by LC-HRMS/MS

Lipids play an important role in coffee bean development, coffee brew and in the effects of coffee on human health. They account for around 17% of the dry bean weight and encompass different classes and subclasses, mostly triacylglycerols (TAG) and a minor quantity of phospholipids (PL) and βN-alkanoyl-5-hydroxytryptamides (C-5HT). To comprehensive profile these different lipids, it is important to evaluate extraction methods that provide high lipid coverage and to analyze the lipids in high-resolution techniques. In this work, liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS) was employed to comprehensive profile lipids from green Arabica coffee beans and to evaluate the extraction efficiency and lipid coverage of three methods: Bligh-Dyer (BD), Folch (FO), and Matyash (MA). The MA method yielded the greatest number of annotated compounds (131 lipids) compared to the other methods. In the positive electrospray ionization (ESI) mode, the main difference among extraction methods was observed for TAG and diacylglycerols, whereas for the negative ESI it was observed differences for phosphatidylinositol (PI), lysophosphatidylinositol and phosphatidic acid (p < 0.05). The analysis of coffees from different maturation stages and/or post-harvest processes were also performed using the MA method. Immature beans were discriminated from mature and overripe beans by its lower levels of C-5HT, PI, phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, and lysophosphatidylethanolamine. These results can help to better understand the coffee lipid composition and its association with coffee quality.

Excavation of coffee maturity markers and further research on their changes in coffee cherries of different maturity

1H NMR detection combined with partial least squares discriminant analysis (PLS-DA) was used to establish models for distinguishing between Arabica coffee immature beans and mature beans. By screening Variable importance in projection (VIP) values of the discriminant model, sugars, caffeoylquinic acids (CQAs), caffeine, trigonelline and quinic acid were confirmed as maturity markers. Response surface method (RSM) was used to filter optimal condition for the simultaneous extraction of sugars, 5-caffeoylquinic acids (5-CQA), caffeine and trigonelline and the best condition obtained was: extraction time 120 min, extraction temperature 50 °C, methanol/water 0.20, solvent/solute 274.65. Under this condition, the content of maturity markers in eight different maturity coffee green beans and pulp were analyzed, and their possible biological functions as well as impact on cupping score were further discussed.

Quality assessment of coffee beans through computer vision and machine learning algorithms

The increasing market interest in coffee beverage, lead coffee growers around the world to adopt more efficient methods to select the best-quality coffee beans. Currently, coffee beans selection is carried out either manually, which is a costly and unreliable process, or using electronic sorting machines, which are often inefficient because some coffee beans defects, such as sour and immature beans, have similar spectral response patterns. In this sense, the present work aimed to assess coffee beans quality using both computer vision and machine learning techniques, such as Support Vector Machine (SVM), Deep Neural Network (DNN) and Random Forest (RF). For this purpose, an algorithm written in Python language was developed to extract shape and color features from coffee beans images. The obtained dataset was then used as input to the machine learning algorithms. The data reported in this study pointed to the importance of color descriptors for classifying coffee beans defects. Among the variables used, the components from RGB (Red, Green and Blue) and HSV (Hue, Saturation and Value) color spaces presented the most relevant contribution for the classification models. Also, the results reported in this study provides evidence that computer vision along with machine learning algorithms can be used to identify and classify coffee beans with a very high accuracy (> 90%). Key words: Deep neural network; classification; artificial intelligence; image processing; granulometry.

Cadmium accumulation and allocation in different cacao cultivars

Cadmium (Cd) is a biologically non-essential heavy metal that can cause toxic effects in plants, animals and humans already at low concentrations compared to other metals. After Cd concentrations in cacao beans of various provenances, particularly from Latin America, were found to exceed the new regulations enforced by the European Union in 2019, there is an urgent need to find measures to lower Cd accumulation in cacao beans to acceptable values. In this research, the long-term cacao cultivar trial CEDEC-JAS in northern Honduras was used to investigate differences between 11 cultivars in Cd uptake and translocation. Sampling of various plant parts, including rootstocks, scions, leaves and beans, from three replicate trees per cultivar and the soil around each tree was conducted at this site. Results indicate that concentrations of available soil Cd were more closely correlated with Cd concentrations of the rootstocks (R2 = 0.56), scions (R2 = 0.59) and leaves (R2 = 0.46) than with bean Cd concentrations (R2 = 0.26). In addition, Cd concentrations of rootstocks, scions and leaves showed close relationships to available soil Cd concentrations, with no significant differences between the cultivars. In contrast, bean Cd concentrations showed only weak correlations to available soil Cd and Cd concentrations in the vegetative plant parts, but significant variation among cultivars. Three cultivars, which were analysed in more detail, showed significant differences in Cd concentrations of mature beans, but not of immature beans. These results suggest that cultivar-related differences in bean Cd concentrations primarily result from differences in Cd loading during bean maturation, possibly due to cultivar-specific differences in the xylem-to-phloem transfer of Cd. The results show that selection of cultivars with low Cd transfer from vegetative parts into the beans has high potential to keep Cd accumulation in cacao beans at levels that are safe for consumption.

Prediction of specialty coffee cup quality based on near infrared spectra of green coffee beans

The growing global demand for specialty coffee increases the need for improved coffee quality assessment methods. Green bean coffee quality analysis is usually carried out by physical (e.g. black beans, immature beans) and cup quality (e.g. acidity, flavour) evaluation. However, these evaluation methods are subjective, costly, time consuming, require sample preparation and may end up in poor grading systems. This calls for the development of a rapid, low-cost, reliable and reproducible analytical method to evaluate coffee quality attributes and eventually chemical compounds of interest (e.g. chlorogenic acid) in coffee beans. The aim of this study was to develop a model able to predict coffee cup quality based on NIR spectra of green coffee beans. NIR spectra of 86 samples of green Arabica beans of varying quality were analysed. Partial least squares (PLS) regression method was used to develop a model correlating spectral data to cupping score data (cup quality).The selected PLS model had a good predictive power for total specialty cup quality and its individual quality attributes (overall cup preference, acidity, body and aftertaste) showing a high correlation coefficient with r-values of 90, 90,78, 72 and 72, respectively, between measured and predicted cupping scores for 20 out of 86 samples. The corresponding root mean square error of prediction (RMSEP) was 1.04, 0.22, 0.27, 0.24 and 0.27 for total specialty cup quality, overall cup preference, acidity, body and aftertaste, respectively. The results obtained suggest that NIR spectra of green coffee beans are a promising tool for fast and accurate prediction of coffee quality and for classifying green coffee beans into different specialty grades. However, the model should be further tested for coffee samples from different regions in Ethiopia and test if one generic or region-specific model should be developed.

High-Throughput Metabolic Profiling of Diverse Green Coffea arabica Beans Identified Tryptophan as a Universal Discrimination Factor for Immature Beans

The maturity of green coffee beans is the most influential determinant of the quality and flavor of the resultant coffee beverage. However, the chemical compounds that can be used to discriminate the maturity of the beans remain uncharacterized. We herein analyzed four distinct stages of maturity (immature, semi-mature, mature and overripe) of nine different varieties of green Coffea arabica beans hand-harvested from a single experimental field in Hawaii. After developing a high-throughput experimental system for sample preparation and liquid chromatography-mass spectrometry (LC-MS) measurement, we applied metabolic profiling, integrated with chemometric techniques, to explore the relationship between the metabolome and maturity of the sample in a non-biased way. For the multivariate statistical analyses, a partial least square (PLS) regression model was successfully created, which allowed us to accurately predict the maturity of the beans based on the metabolomic information. As a result, tryptophan was identified to be the best contributor to the regression model; the relative MS intensity of tryptophan was higher in immature beans than in those after the semi-mature stages in all arabica varieties investigated, demonstrating a universal discrimination factor for diverse arabica beans. Therefore, typtophan, either alone or together with other metabolites, may be utilized for traders as an assessment standard when purchasing qualified trading green arabica bean products. Furthermore, our results suggest that the tryptophan metabolism may be tightly linked to the development of coffee cherries and/or beans.

Discrimination between defective and non-defective roasted coffees by diffuse reflectance infrared Fourier transform spectroscopy

The objective of this work was to evaluate the feasibility of employing Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) for discrimination between defective and non-defective coffees after roasting and grinding. Defective (black, immature and sour) and non-defective Arabica coffee beans were submitted to light, medium and dark roasts at 220, 235 and 250 °C. Principal Components Analysis of the DRIFTS spectra (normalized or not) and of the first derivatives of the spectra provided separation of the samples into four groups: non-defective, black, dark sour and light sour, with immature beans scattered among the sour samples. Classification models were developed based on Linear Discriminant Analysis and recognition and prediction abilities of these models ranged from 95 to 100%. Such results indicate that DRIFTS presents potential for the development of a fast and reliable analytical methodology for discrimination between defective and non-defective coffee after roasting and grinding.

Culinary alternatives for common beans (Phaseolus vulgaris L.): sensory characteristics of immature seeds

Immature bean seeds feature in several dishes in southern Europe; however, they are not used in all traditional areas of dry beans cultivation. To determine whether differences in the use of immature seeds are due to cultural reasons or intrinsic properties of the seeds, the prestigious varieties of beans cultivated in three areas of Spain with different traditions regarding the use of immature seeds in bean dishes were studied. We found differences in the culinary and sensory traits between beans harvested when mature and those harvested when immature in the three areas. However, the degree and direction of these differences varied according to the area. Moreover, the different varieties tested within each area responded differently. The sum of the genetic, environmental and interaction effects results in complex alternatives to the mature beans; the gastronomic tradition has taken advantage of only some of these alternatives. A lack of traditional dishes using immature beans does not mean that the local beans harvested when immature lack suitable sensory traits. Specific trials in each area of cultivation can reveal alternative textures and bean flavour intensities in immature seeds.

Discrimination between defective and non-defective Brazilian coffee beans by their volatile profile

The coffee roasted in Brazil is considered to be of low quality, due to the presence of defective coffee beans that depreciate the beverage quality. In view of the fact that coffee flavour is directly related to the volatile compounds produced during roasting, the objective of the present study was to perform a comparative evaluation of the volatile fraction of defective (black, immature, sour) and healthy coffee beans, in order to find possible chemical markers for detection of defective coffee beans in roasted coffee. Volatiles extraction and concentration was performed by solid phase micro-extraction (SPME) of the roasted coffee headspace, using a triple phase (divinylbenzene/carboxen/polydimethylsiloxane) fiber. Analysis of the volatile profiles was performed by GC–MS. The results obtained showed that the proposed methodology was adequate for extraction, concentration and analysis of the coffees volatile profile. Several substances were identified as possible markers for differentiating black, sour and immature beans from healthy coffee beans. Statistical analysis of the data by principal components (PCA) demonstrated that the volatile profile enables the differentiation of healthy and defective coffees. The data were separated into two major groups, one represented by immature and black beans and the other by healthy and sour coffee beans. Such results indicated that black and sour beans can be associated to fermentation of immature and of healthy beans, respectively.

Use of Leafstalks of Japanese Taros and Immature Beans in the Tokai Region of Japan

Use of Leafstalks of Japanese Taros and Immature Beans in the Tokai Region of Japan

Content and Composition of Isoflavonoids in Mature or Immature Beans and Bean Sprouts Consumed in Japan.

The content of 9 types of isoflavonoids (daidzein, glycitein, genistein, formononetin, biochanin A, coumestrol, daidzin, glycitin and genistin) in 34 domestic or imported raw beans including soybeans, 7 immature beans and 5 bean sprouts consumed in Japan were systematically analyzed. Each isoflavonoid was analyzed in total after acid hydrolysis to the aglycone, and intact individual isoflavonoids were also analyzed without hydrolysis. After the sample clean up, daidzein, glycitein, genistein, formononetin, biochanin A, daidzin, glycitin and genistin were determined by HPLC with a diode array detector and coumestrol was determined by spectrofluorimetry. The content and composition of isoflavonoids varied greatly between soybean sprouts, immature soybeans and mature beans of the same type but of different source. Isoflavonoid content was highest in mature soybeans. The composition of isoflavonoids differed in each growth stage of soybeans. In other beans, the largest content of isoflavonoids was found in mature chickpeas, but this value was less than 1/27 of the isoflavonoid content in mature soybeans. Thus, the contribution of beans other than soybeans to the daily intake of isoflavonoids in a Japanese diet is negligible.

Bean-Curd Consumption in Hong Kong

This article examines soybean curd and kindred byproducts in Hong Kong, where an ethnographic survey revealed that traditional forms of soy products have been supplemented with new consumption practices. Soyfoods have been part of Asian food systems for millennia. But century ago, soybeans entered the world market, taking on new nutritional and economic roles. Swiftly changing technology and unexpected market opportunities have since transformed the place of soybeans in the panorama of global food. Hong Kong is now place where novel soyfood-eating styles are becoming fashionable, and these are diffusing to other, more Western societies. (Asia, anthropology of food, globalization) This essay introduces the role of bean curd (Mandarin doufou, Cantonese dauh-fuh)(1) and other soyfoods in the cultural and culinary life of Hong Kong people, and reports on ethnographic research there that includes retailing stores and markets, bean-curd factory, and brief consumer survey. The article also seeks to situate that survey in the larger context of world food history, particularly as related to the soybean (Glycine max). Soybeans are domesticated legume of enormous nutritional, economic, and culinary importance in Asia. During the last century, soybeans and many soy byproducts have entered massively into world commerce on scale that could scarcely have been imagined 100 or even 50 years ago (Mintz and Du Bois n.d.).(2) The history of soybeans and soyfoods stretches back over three millennia. Huang (2000:18, 27) assigns the domestication of soybeans to the beginning of the Chou (Zhou) dynasty. Its cultivation spread widely on the Asian mainland and Japan. Huang (2000) believes that soybeans may have been eaten in place of cereals in China after its domestication. That legume should be eaten like complex carbohydrate and as the core of meal is very unusual. But while soybeans are edible and can be prepared and consumed like other beans, they eventually proved to be most useful as human food when processed into bean curd or related products. The undesirable gastrointestinal effects of eating unprocessed soybeans might help to explain why more skill must have been invested in producing diversified, digestible, and delicious byproducts from the soybean than from any other legume so early in history. In his breathtaking survey of the subject, Huang (2000:293) writes: [I]n spite of its admirable nutrient content, the soybean is far from being an ideal food. Apart from the immature beans which can be eaten directly as vegetable, the raw mature beans as harvested and stored suffer from several serious defects when used as food. Firstly, the soy proteins are difficult to digest. The beans contain proteins, such as trypsin inhibitor, which suppress the action of proteases in the human digestive system. Unless they are thoroughly cooked to inactivate the inhibitors, the proteins would be poorly digested resulting in growth inhibitions, pancreatic hypertrophy and hyperplasia. Secondly, the carbohydrate component contains raffinose and staehyose, two [Alpha]-galaetosides which are not degraded by human digestive enzymes. They pass into the colon where they are metabolised by anaerobic bacteria, leading to the generation of gas and flatulence. be sure, both defects are shared by other legumes, but the undesirable effects may be more pronounced in soybeans--in ancient China these were eaten as grains in much larger amounts than other legumes, which were consumed as vegetables. Finally, soybean contains so-called unpleasant beany flavour which was one of the major obstacles that had to be overcome before soybean oil could be commercialised on large scale. To circumvent these problems ... the Chinese developed ways of processing soybeans to produce foods that are wholesome, attractive and nutritious (Huang 2000:295, 299). Though Huang calls the exact origins of doufu a major unsolved problem in the history of food science and nutrition of China, he concludes that the process may have been developed sometime around the end of the Han dynasty (Huang 2000:216). …

Long-Chain Aliphatic β-Diketones from Epicuticular Wax of Vanilla Bean Species. Synthesis of Nervonoylacetone

Analysis of the neutral lipids from Vanilla fragrans and Vanilla tahitensis (Orchidaceae) without saponification resulted in the isolation and identification of a new product family in this plant: beta-dicarbonyl compounds. The compound structures are composed of a long aliphatic chain with 2,4-dicarbonyl carbons and a cis double bond at the n-9 position. They represent approximately 28% of the neutral lipids, that is, 1.5%, in immature beans, and approximately 10% of the neutral lipids, that is, 0.9%, in mature beans. Using retention indices, gas chromatography-mass spectrometry, derivatization reactions, and chemical degradation, five beta-dicarbonyl compounds have been identified including 16-pentacosene-2,4-dione, 18-heptacosene-2,4-dione, 20-nonacosene-2, 4-dione, 22-hentriacontene-2,4-dione, and 24-tritriacontene-2, 4-dione. Among them (Z)-18-heptacosene-2,4-dione, or nervonoylacetone, has been synthesized in two steps starting from nervonic acid. The major constituent, nervonoylacetone, represented 74.5% of the beta-dicarbonyl fraction. The range of these compounds has been studied in relation with bean maturity for V. fragrans and V. tahitensis species. This compound family has not been found in the leaves or stems of any of the three vanilla species studied and is markedly absent in the beans of V. madagascariensis.