Studies on Cause of Color Reversion of Edible Soybean Oil and its Prevention

Tocored as a precursor of color reversion of soybean oil has been isolated and identified. We have found that the moisture of raw soybeans is closely related to the tocored content in crude oil and the yield of tocored is maximum when the moisture of soybeans is 15~18%. It seemed that tocored in crude oil were completely removed by the refining processes, but 30% of it remained in the colorless form in refined and deodorized oil and turned into tocored during storage or on heating the oil to a higher temperature. Tocopherols are relatively stable in refined oil and are not oxidized to tocored under a milder condition, such as the oxidation with air. Neither tocopherol nor tocored but “tocored in colorless form” is really the precursor of color reversion in soybean oil.     

Studies on Desiccation and Storage of Mango Seeds

Mango (Mangifera indica L.) seed is recalitrant which taken from ripened fruits con,ained as high as 69.2'–75.5% moisture content (The moisture content of embryonic axis is 73.8–86.3%). When seeds were naturally dried for 8 days, the moisture content declined to 39.1% (in embryonic axis the moisture content declined to 46.5%) and the viability of seeds completely lost. Embryonic axis lost water slower than whole seed because of the prevention of desiccation by the large cotyledons. During natural desiccation, the conductivity of leachate increased rapidly from 2.2 μΩ·cm-1·g-1 (the same unit below) to 56.7, whereas the activities of dehydrogenase and acid phosphatase decreased drastically. When seeds were rapidly dried for 42 hours, the moisture content declined from 75.5 to 29.9%, the conductivity of leachate increased from 1.8 to 36.9 and the percentage germination changed from 100% to 10%. Desiccation damaged the cell membrane and decreased the activities of enzymes. Rapid drying was better for maintaining longevity than natural (slow) drying because the former did less damage to the cell membrane than natural (slow) drying as shown in the conductivity changes. The moisture content of excised embryonic axis decreased to 11.8% when they were dried for 8 hours by silicagel. The survival percentage of these embryonic axis was 80% when they were incubated in MS+0.2 mg/L BA+2.0 mg/L NAA+500 mg/L gln+3% sucrose+0–9% agar medium. Seeds with 51.0% moisture content (rapidly dried for l0 hours by electric fan blowing) had 65% viability after 7 months wet storage with the polyethylene bag at 15℃.     

Total Tocopherols,Carotenoids, and Fatty Acids Content Variation of Pistacia atlantica from Different Organs’ Crude Oils and Their Antioxidant Activity during Development Stages

The current study investigated the effect of developmental stages on the chemical composition and the antioxidant activity of fifteen crude oil samples obtained from Pistacia atlantica Desf. leaves, galls, and fruits. Twelve fatty acids were detected by GC/FID, linolenic acid (C18 : 3) was the major fatty acid detected in leaves crude oils that registered [41.73 % (P<0.05)] on the last stage. The best content of tocopherols and carotenoids was recorded at the last stage for leaves and galls oils, respectively, with values of [1.530±0.01, 0.52±0.01 (P<0.05) mg α‐tocopherol equivalent/g DW] and [86.60±0.95, 69.15±0.13 (P<0.05) μg β‐carotene equivalent/g DW]. For fruits oils, the content varied depending on the levels of fruits maturation. The results from DPPH, FRAP, and ABTS assays revealed that the antioxidant activity increased with the increasing content of tocopherols and carotenoids in leaves and galls oils during development stages, and varied for fruits oils depending on the ripening stages. Moreover, according to PCA analysis, the best phytoconstituent content and antioxidant activity were attributed to P. atlantica Desf. fruit's crude oils. Also, a strong relationship was found between the antioxidant activity and bioactive phytochemical components, such as tocopherols, carotenoids, and omega‐three fatty acid, which confirmed that P. atlantica Desf. crude oils present a valuable source of natural antioxidant that could be used for pharmaceutical and food industries purposes.     

Effect of viscoelastic relaxation on moisture transport in foods. Part II: Sorption and drying of soybeans

The general fluid transport equation presented in Part-I of this paper is used for predicting moisture transport and viscoelastic stresses during sorption and drying of soybeans. Predicted drying curves were validated using experimental data obtained from literature (average absolute difference 6-13%). For drying temperatures used in the soybean processing industry (70–93 °C), smooth moisture profiles were obtained, which indicated Fickian (Darcian) transport. As the drying temperature approached the glass transition temperature (25 °C at 10% moisture content), the moisture profiles became sharper, which indicated non-Fickian (non-Darcian) transport. The viscoelastic stress profiles clearly exhibited the role of the force terms during imbibition and drying. Increase in drying temperature tends to decrease the stress relaxation function but reduction in moisture content during drying tends to increase it. The increase in stress due to the reduction in moisture content below 10% was not compensated by an increase in drying temperature. Drying of soybeans below 10% moisture content should be avoided in the industry because this will lead to thicker flakes that reduce the amount of oil recovery. During imbibition of soybeans, a high magnitude of stresses was obtained in the rubbery regions, which may cause critical regions prone to fissuring. The role of glass transition on stress development and critical region development was clearly observed during drying and imbibition of soybeans.Revised version: 5 October 2003     

Recovery of native protein from potato root water by expanded bed adsorption with amberlite XAD7HP

Potato root water (PRW) contains ～1.5% protein. In this study, expanded bed adsorption (EBA) chromatography with Amberlite XAD7HP resin adsorbent was used to isolate native protein from crude PRW. The optimal pH and ionic strength for potato protein binding onto Amberlite XAD7HP were 5.0 and 20 mmol/L. The EBA-refined proteins were dried by vacuum freeze drying and spray drying at varying outlet temperatures. Results indicated that low temperature spray drying was the most cost effective method with respect to retaining protease inhibitor activities. The dried protein concentrates appeared bright yellow or dark reddish brown, with a total glycoalkaloid content of ～170 μg/g. The protease inhibitor activity was ～400 mg/g and 11 ～ 12 mg/g for trypsin inhibition and chymotrypsin inhibition, respectively. The results presented here suggest that EBA using Amberlite XAD7HP as the adsorbent is a feasible strategy for the direct adsorption of native protein from crude PRW.     

Effects of processing methods on nutritional composition and antioxidant activity of mealworm (Tenebrio molitor) larvae

We examined the effects of different processing methods on the nutritional composition and antioxidant activity of mealworms. After processing with nine methods, we calculated the contents of protein, fat, ash, carbohydrate, minerals (P, Ca, K, Fe, Na), vitamin B group (B₁, B₂, B₃), moisture, and calories. When processed by freeze drying among freeze drying, hot air drying, oven broiling, roasting, pan frying, deep frying, boiling, steaming, and microwaving, the contents of protein, some minerals, and vitamins were the highest. The content of total minerals was lowest after deep frying, and those of vitamin B₁ and B₃ were the lowest after microwaving. Antioxidant activity was then evaluated using DPPH and ABTS radical scavenging assays. DPPH assays showed that microwaving, freeze drying, deep frying, steaming, boiling, and oven broiling of mealworms yielded scavenging activities of 20.9–29.0% at 2,000 μg/mL, which was similar to the activity level (22.7–33.2%) of 40–60 μM tocopherol. ABTS assays confirmed that only freeze‐dried mealworms at 2,000 μg/mL exhibited higher activity than 10 μM tocopherol. Interestingly, similar trends were found for antioxidant activity levels and total phenolic contents in mealworms.     

Comparison of Chemical Profile and Antioxidant Capacity of Seeds and Oils from Salvia sclarea and Salvia officinalis

Composition of tocopherols, tocotrienols, carotenoids, fatty acids, as well as hydrophilic and lipophilic antioxidant activities, were determined in seeds of two Salvia species and oils obtained from them. Both seeds contained a large amount of oil (around 20%) rich in polyunsaturated fatty acids. While Salvia officinalis seed oil can be classified as oleic‐linoleic oil, the predominant fatty acid in Salvia sclarea was α‐linolenic acid (around 54%). Among tocols, the main isomers in both seeds and oils were γ‐tocopherol, followed by α‐tocopherol. Concerning carotenoids, their concentration was around 0.75 mg/100 g of seeds and 0.16 mg/100 g of oils, with a predominance of lutein. Oil and seeds of S. officinalis exhibited higher antioxidant potential compared to S. sclarea investigated samples which could be attributed to higher content of total vitamin E and carotenoids. This study provides results that enables use of two Salvia species as new alternative sources of vegetable oils.     

Antioxidant content of oil and defatted meal obtained from borage seeds by an enzymatic-aided cold pressing process

Polyphenols content (as catechin equivalents) and tocopherol content were determined in borage defatted meal and borage oil, respectively. In addition, antioxidant activity of extracts obtained from borage defatted meal was evaluated. A cold pressing process was used for the extraction of Borago officinalis oil, resulting in a defatted meal (by-product). Polyphenols from this defatted borage meal were extracted using several solvents. An extract containing highly soluble solids and phenolic compounds with antioxidant activity (as free radical-scavenging, DPPH) was obtained when methanol was used. The tocopherol content was higher in oil extracted by cold pressing than in oil extracted with petroleum ether as organic solvent. An enzymatic treatment was applied (45 °C, 20% moisture, 0.25% E/S ratio, 1:1 Olivex:Celluclast enzymatic mixture) previously to borage oil extraction, which improved the antioxidant content in the borage defatted meal by three-folds, as compared to the values obtained by a nonenzyme-aided process.     

Survival of root‐lesion nematodes (Pratylenchus thornei) after wheat growth in a vertisol is influenced by rate of progressive soil desiccation

The root‐lesion nematode (Pratylenchus thornei) is a major pathogen of wheat in the subtropical grain region of eastern Australia. Experiments were conducted to learn whether soil desiccation can account for the rapid fall in peak P. thornei population densities noted in the field after wheat matures. The decline in population densities of P. thornei after growth of wheat was measured on progressive desiccation of soil with roots by fast and slow drying methods. The vertisolic soil of initial moisture content 45% w/w (or matric potential of pF 3.3) was dried in 5% decrements to an air‐dried gravimetric moisture content of 15% (pF 5.6) taking 10.7 h for fast drying and 91.5 h for slow drying. After drying, live nematodes were extracted with Whitehead trays for 2 and 7 days and counted in four life stages (adults and juvenile stages J2, J3 and J4). Fast drying resulted in a sigmoidal decline in total P. thornei with only 5% of the population alive in soil at 15% moisture content, but slow drying had no significant effect on the population density. The percentage of nematodes extracted at 2 days compared with the total extracted over 7 days in undried soil (～89% of total) declined quadratically on desiccation to be 48% (fast drying) and 78% (slow drying) at 15% moisture content. With fast drying, the proportion of adults and J2 decreased whereas the proportion of J4 increased as the soil dried. With slow drying, the proportion of J2 and J3 stages decreased while the proportion of J4 increased. Thus the J4 or pre‐adult was the life stage most tolerant of soil desiccation. Time is required for P. thornei to go into a state of anhydrobiosis as a soil dries and this information can be used to model P. thornei survival in the field based on environmental parameters.     

胡萝卜吸附式低温干燥特性的研究

对胡萝卜吸附式低温干燥过程的干燥特性进行了试验研究。考察了干燥气体 (空气 )的湿度和风量以及物料粒度对胡萝卜干燥特性和复水比的影响 ,得到形状相似的干燥曲线 ,用自定义最小二乘法拟合均能获得较好的结果。结果表明 :吸附式低温干燥过程可使被干燥物料达到超干水平 (含水率 <5 % ) ;增加干燥气体流量对干燥过程进行有利 ,当气体流量从 2 0 0L/h增加到 4 0 0L/h时 ,胡萝卜含水率从 4 1 13%降低到 34 93% ;被干燥物料颗粒大小和形状对干燥过程有显著影响 ;经过吸附式干燥后的胡萝卜色泽鲜艳 ,无褐变 ,外表品质优于热风干燥。吸附式低温干燥后胡萝卜的复水比 (6 5 2 )显著高于热风干燥 (1 78)。     

Effects of Moisture Content and Temperature on Storage of Metarhizium flavoviride Conidia

The effects of moisture content and temperature on the medium-term (3-4 months) storage of conidia of Metarhizium flavoviride were investigated. Conidia harvested after 24 days of culturing on rice showed greater tolerance to long storage than conidia from 12-day cultures. The moisture content of the conidia was of greatest importance; at harvest from the culture, conidial moisture contents could be 40%, while the optimal moisture content for storage was found to be 4-5%. Dried conidia stored in oil benefited from the addition of dried silica gel, as did conidia stored as powder. A range of mineral oils proved satisfactory for storage, and when dried silica gel was added to suspensions, germination levels were 79.8% after 105 days at 28-32 C. Dried conidia stored in oil maintained germination levels of up to 96 and 85% after 80 days at 10-14 C and 28-32 C respectively. Dried conidia stored as powder retained germination levels of 95% at 10-14 C, but only up to 27% at 28-32 C. In another experiment, dried conidia maintained greater than 90% germination over 128 days, with or without silica gel at 10 - 14 C or -15 - -18 C.     

Composition of fatty acids triacylglycerols and unsaponifiable matter in Calophyllum calaba L. oil from Guadeloupe

The composition of the kernel oils of two Calophyllum species (Calophyllum calaba L. and Calophyllum inophyllum L.) was investigated. The physico-chemical properties and fatty acid composition of the kernel oils were examined. In two species, oleic acid C18:1 (39.1-50%) is the dominating fatty acid followed by linoleic acid C18:2 (21.7-31.1%) as the second major fatty acid. Stearic C18:0 (13.4-14.3%) and palmitic C16:0 (11-13.7%) acids are the major saturates. The oils contains an appreciable amount of unsaturated fatty acids (70.8-73.10%). Most of the fatty acids are present as triacylglycerol (76.7-84%), twenty one triacylglycerols are detected with predominantly unsaturated triacylglycerols. The total unsaponifiable content, its general composition and the identity of the components of the sterol and tocopherol fractions are presented. In both species, analysis of the unsaponifiable fractions revealed the preponderance of phytosterols, mainly stigmasterol (35.8-45.1%) and beta-sitosterol (41.1-43.1%). Among the eight tocopherols and tocotrienols present in two species, variations exist; alpha-tocopherol (183 mg/kg) is the main tocopherol in Calophyllum calaba L. and Delta-tocotrienol (236 mg/kg) is the dominant tocotrienol in Calophyllum inophyllum L.     

Studies on the Nutritional Value of Tempeh

1. The nutritional value of tempeh in comparison with that of unfermented soybeans was studied in rat feeding experiment. It was observed that the PER value of tempeh (fresh or stored) was not significantly different from that of the unfermented soybeans (fresh or stored).

2. The peroxide value of the oil of stored tempeh powder was only 10% of that of stored soybean powder. Red blood cells of rats receiving tempeh were less than 20% in hemolysis by dialuric acid whereas hemolysis was 100% for the rats receiving the unfermented soybeans. Serum tocopherol was 0.14±0.05 mg/dl in the former group, but 0.07±0.05 mg/dl in the latter. Liver TBA values were 0.20±0.05 O. D./g and 0.65±0.13 O. D./g in the tempeh and the unfermented soybeans group, respectively.

3. Subsitution of whole egg for tempeh to supply 30% of protein in the diet improved the quality of the protein as measured by the protein efficiency ratio. An equal improvement was accomplished by supplementation of tempeh with lysine, methionine, and threonine in such amounts as the level of these amino acids equal to that in the tempeh-egg diet.     

A study of a bacterial immobilization substratum for use in the bioremediation of crude oil in asaltwater system

An immobilization matrix, Drizit, was examined for use in the bioremediation of oil in asaltwater system. The support was examined by scanning electron microscopy, cell-loadingcapacity, absorption of Ekofisk crude oil, the effect on cell recoverability of dryingDrizit-immobilized cells at room temperature, 55°C or freeze drying and storage for up to 3months, and the capability of immobilized Pseudomonas fluorescens to enhance biodegradation ofpetrol (Slovene diesel) in a saltwater system. Results showed that Drizit is an ideal immobilizationsubstratum for use in bioremediation, and the substratum was found to have a good cell-loadingcapacity (3·75 mg protein g⁻¹ substratum) and a high absorbency of oil(7·49 g Ekofisk g⁻¹ substratum). After drying the immobilized cells at roomtemperature, 55°C or freeze drying and subsequent storage, cells were not recoverable after 2weeks, 1 week or 2 months, respectively, and a significant decrease was seen in the number ofcells recovered after drying and 1 week's storage in all cases. Enhanced biodegradation of C₁₃–C₁₈ pristane and phytane, in petrol (Slovene diesel) occurred with theimmobilization of Ps. fluorescens to Drizit. An average degradation of 73·8%occurred in the immobilized system in comparison with the free system which resulted in anaverage degradation of 39·8%. When the two systems were supplemented with nitrates andphosphates, degradation in the free supplemented system increased to an average of 72·4%.However, no significant difference in biodegradation was found between the immobilized systemand the immobilized system supplemented with nitrates and phosphates which achieved anaverage degradation of 74.15%.     

Coffee oil as a potential feedstock for biodiesel production

A preliminary evaluation of the feasibility of producing biodiesel using oil extracted from defective coffee beans was conducted as an alternative means of utilizing these beans instead of roasting for consumption of beverage with depreciated quality. Direct transesterifications of triglycerides from refined soybean oil (reference) and from oils extracted from healthy and defective coffee beans were performed. Type of alcohol employed and time were the reaction parameters studied. Sodium methoxide was used as alkaline catalyst. There was optimal phase separation after reactions using both soybean and healthy coffee beans oils when methanol was used. This was not observed when using the oil from defective beans which required further processing to obtain purified alkyl esters. Nevertheless, coffee oil was demonstrated to be a potential feedstock for biodiesel production, both from healthy and defective beans, since the corresponding oils were successfully converted to fatty acid methyl and ethyl esters.     

一种简便、快速测定鹅膏多肽毒素的方法——抑芽法*

低浓度（5-10ngml-1）的鹅膏毒肽(amatoxins) 能专一性抑制RNA聚合酶Ⅱ的活性,高浓度（为RNA聚合酶Ⅱ103-104倍的浓度）也能抑制RNA聚合酶Ⅲ的活性,因而影响细胞mRNA的转录和蛋白质的合成,抑制种子的萌发和生长。根据此原理我们建立了一种以植物种子萌发试验检测鹅膏毒肽的方法,称之为“抑芽法”（bud-inhibited assay）。该方法简便、实用、准确。操作流程：45℃干燥至恒重的鹅膏菌等子实体菌盖;水提法提取毒素并用氯仿沉淀蛋白质等;粗毒液浓度为0.025-0.05gml-1干子实体;萝卜或绿豆种子培养温度为28℃,培养时间为24-72h。绿豆芽下胚轴生长被抑制率在95%以上,可能为鹅膏毒肽含量高的剧毒鹅膏菌;当被抑制率在60-80%,可能为鹅膏肽含量较低的微毒鹅膏菌;当被抑制率在30%以下时,可能是不含鹅膏菌肽的鹅膏菌。     

Additives to biological substances. III. The moisture content and moisture uptake of commonly used carrier agents undergoing processing conditions similar to those used in the preparation of international biological standards

Aqueous solutions of the carbohydrates alpha alpha'-trehalose, mannitol and lactose, human serum and human albumin were freeze-dried in ampoules and part of each batch was further desiccated over phosphorus pentoxide in a manner similar to that used to prepare international biological standards and related materials. The residual moisture present in the preparations and their uptake of moisture was then measured by Karl Fischer titration. In ampoules open to atmosphere [22 degrees C, 34% relative humidity (RH)] freeze-dried serum, albumin, lactose and alpha alpha'-trehalose all exhibited hygroscopic properties, their moisture contents rising over a period of 24 h, to 10%, 8%, 8% and 7%, respectively. Mannitol when dried to low moisture levels did not exhibit hygroscopic properties, but the residual moisture in different freeze-dried batches was very variable, possibly as a result of that solid's sponge-like and/or crystalline microstructure. When exposed to the same conditions, dried materials in ampoules fitted with polythene capillary leak plugs (used routinely at this Institute during the preparation of Biological Standards) exhibited a considerably reduced rate of moisture uptake. The effect of secondary vacuum drying over phosphorus pentoxide on the moisture content of these preparations is also reported.     

Characteristics and composition of Parkia biglobbossa and Jatropha curcas oils and cakes

Parkia biglobbossa (PKBS) and Jatropha curcas (JTC) seeds were analysed for their proximate composition. The seeds oils were analysed for fatty acid, lipid classes, sterols and physicochemical characteristics. Proximate analysis revealed that the percentage crude protein, crude fat and moisture in PKBS were 32.40%, 26.525% and 10.18% respectively and 24.60%, 47.25% and 5.54% in JTC. Campesterol, stigmasterol, beta-sitosterol, Delta5-avenasterol and Delta7-stigmasterol were identified in the seed oils, but beta-sitosterol was most abundant, constituting 71.9% in JTC and 39.5% in PKBS. JTC oil had 72.7% unsaturated fatty acids with oleic acid predominating, while PKBS had 62% unsaturated fatty acids with linoleic acid being the most abundant. Results of lipid classes showed triglyceride as the dominant lipid species in the seed oils. Physicochemical analysis of the seed oils showed that they could be classified as semi drying oils and that they could be found applicable in alkyd resin and soap manufacture.     

The effects of desiccation on seeds of Acer saccharinum and Aesculus pavia: recalcitrance in temperate tree seeds

This study was undertaken to determine how the results from lipid, moisture, and differential scanning calorimetry analyses conducted on silver maple (Aceraceae: Acer saccharinum L.) and red buckeye (Hippocastanaceae: Aesculus pavia L.) compared with those obtained from previous studies on white and water oaks (Fagaceae: Quercus alba and Q. nigra), and the tropical zone species American muskwood (Meliaceae: Guarea guidonia) and carapa (Meliaceae: Carapa guianensis). Seeds were air-dried at room temperature for 9-11 days. At intervals, germination was tested, moisture determined, and lipids extracted. It was found that, like the other recalcitrant seeds, (1) viability was greatly reduced or lost after 11 days of drying, (2) percentage changes in individual fatty acids were not related to seed viability, and (3) results from the differential scanning calorimetry studies revealed a strong relationship between enthalpy/onset data from the embryo and cotyledon tissues and loss of viability. Also, silver maple seeds experienced a 50% reduction in viability by day 5 of drying and retained an axis moisture content over 25% throughout the experiment. However, unlike the other recalcitrant seeds surveyed, both silver maple and red buckeye had a significant reduction in the total amount (mg/g) of cotyledon lipids as the experiment progressed. However, no decrease in the unsaturated/saturated fatty acid ratio was found, so we conclude that in these species lipid peroxidation is not a marker of declining seed viability. Also, red buckeye seeds did not lose 50% viability until after day 8 of the experiment, and axis moisture content fell well below 20% as the seeds dried.     

Effect of enzymatic and hydrothermal treatments of rapeseeds on quality of the pressed rapeseed oils: Part I: Antioxidant capacity and antioxidant content

Response surface methodology was used to evaluate the quantitative effects of three independent variables: rapeseed moisture content, concentration of the added enzymes and conditioning temperature, on the antioxidant capacity and total phenolic, tocopherol, and phospholipid contents in the enzyme-treated rapeseed oils. The highest antioxidant capacity (1220.0, 964.8 μmol TE/100 g) total phenolic (83.3, 74.0 mg SA/100 g) and phospholipid (12,532, 12,376 mg/kg) contents reveal two rapeseed oils extruded from seeds contained 11% moisture, treated with cellulolytic and pectolytic enzymes (0.05%), respectively, and heated at 120 °C. However, the highest content of total tocopherols was determined in rapeseed oils pressed from seeds with 7% moisture, after addition of cellulolytic (0.05%) and pectolytic (0.1%) enzymes, heated at 90 and 105 °C, respectively. Total phenolic and phospholipid contents in the enzyme-treated rapeseed oils correlated significantly (p < 0.0000001) with antioxidant capacities of oils (R² = 0.8710 and 0.6581, respectively). Experimental results of the antioxidant capacity, total phenolic, tocopherol and phospholipid contents were close to the predicted values calculated from the polynomial response surface models equations (R² = 0.9727, 0.9870, 0.8390 and 0.9706 for the cellulolytic enzyme-assisted rapeseed oils and R² = 0.9148, 0.9489, 0.9426 and 0.9479 for the pectolytic enzyme-assisted rapeseed oils). The optimum rapeseed moisture content, enzyme concentration and conditioning temperature for the cellulolytic and pectolytic enzyme-treated rapeseed oils were 11% and 9.7%, 0.08% and 0.1%, and 120 °C, respectively.