Effects of avocado and soya bean lipidic non-saponifiables on the components of skin connective tissue after topical application in the hairless rat: biophysical and biomechanical determination

The non-saponifiable lipidic fractions of avocado and soya bean applied percutaneously to hairless rats for 15 days had been shown to produce biochemical modifications of dermal connective tissue components: increases of soluble collagen and of the ratio soluble collagen/insoluble collagen. In this present study, we tried to show whether these biochemical modifications could be confirmed by biophysical analytical methods and could affect the biochemical properties of the skin. The experiments were carried out on three groups of rats treated by application to the dorsal skin, either with 0.9% NaCl (control), or sweet almond oil (vehicle), or with a mixture of 2/3 soya bean and 1/3 avocado in solution at 5% of sweet almond oil (treated group). After 15 days treatment, the rats were killed and the skin of the treated area dissected. X-ray diffraction diagrams were recorded by varying the position of previously dried samples in controlled conditions. Results indicated that the vehicle decreased the orientation degree of collagen fibres, acting on their reticulation. The addition of the non-saponifiable fraction did not significantly add to the vehicle effect. The study of thermostability of the cutaneous collagen by differential scanning calorimetry showed that non-saponifiables increased the slope of the rise of temperature of denaturation. The quantity of heat absorbed during the denaturation (enthalpy variation) reached around 0.04 J mg^?1 of collagen in the control groups and did not exceed 0.03 J mg^?1 of collagen in the treated ones. Taken in conjunction with previous work it is probable that the non-saponifiables increase the proportion of soluble collagen. The elasticity of whole skin, determined by a static method using an Instron exten-siometer was significantly modified by treatment with non-saponifiables. They produced a decrease of the elasticity module. These results correspond to a decrease of collagen reticulation degree. L'action des insaponifiables d'avocat et de soja sur le tissu conjonctif par application topique sur le rat. Determination biophysique et biomecanique     

Biochemical effects of unsaponifiable lipidic components of avocado and soya bean administered percutaneously on the connective tissue components of hairless rat skin

The unsaponifiable lipidic fractions of avocado and soya bean were administered percutaneously, on the dorsal skin of hairless rats for 15 days, in a 5% sweet almond oil solution. This treatment produced a modification of dermal connective tissue components. The biochemical analysis showed an increase of soluble proteins, especially of salt soluble collagen together with a decrease of proteins insoluble in neutral buffer. The ratio, soluble proteins:insoluble proteins, increases as well as the ratio soluble collagen: insoluble collagen. These modifications can be considered as a result of the activation of connective tissue metabolism. The above results are in agreement with those obtained when the unsaponifiables were administered per os to rats. Effets biochimiques, sur le tissu conjonctif sous cutané des insaponifiables de soja et d'avocat adminstrés par voie percutanée chez le rat sans poils     

Effects of cooked or roasted full-fat soya bean and soya bean meal on performance and carcass characteristics of growing-finishing pigs

Abstract : Three maize-based diets were formulated to contain 25% each of cooked, or locally roasted full-fat soya bean, or 20% soya bean meal. The diets were fed to 24 Large White, Landrace, Hampshire and Duroc crossbred pigs from 32·75 kg average weight to 60·2 kg liveweight in a single-way classification bireplicate trial. Average daily feed, average daily gain and feed to gain ratios for the respective diets were 2·19, 2·05 and 2·16 kg; 0·58, 0·60 and 0·61 kg; and 3·88, 3·50 and 3·62. These differences were not statistically significant (P > 0·05). The linear measures and jointed proportions of the carcasses, as well as pig organ weights, were statistically the same for the three test diets. The pigs fed full-fat soya bean however produced soft-fat carcasses. These results suggest that full-fat soya bean, which is appropriately heat-processed, may effectively replace soya bean meal in growing-finishing pig diets.     

裙带菜豆奶的研制

以裙带菜、豆奶为主要原料,配以甜味剂、稳定剂、乳化剂等,经调配、均质、杀菌等处理,制成一种色泽浅绿,气味芳香、酸甜适口、营养丰富的裙带菜豆奶复合饮料.采用单因素试验确定裙带菜的添加量,通过3因素3水平试验确定乳化剂和稳定剂的配比,通过4因素3水平试验确定裙带菜豆奶饮料的配方,确定的工艺条件是:裙带菜的添加量是10％,蔗糖酯、黄原胶和CMC-Na的添加量分别是0.06％、0.10％和0.10％,蔗糖、柠檬酸、奶粉和混合汁的添加量分别是5％、0.02％、2％和70mL.     

Thermally treated soya bean oleosomes: the changes in their stability and associated proteins

Oleosomes are subcellular organelles present naturally in plant seeds for storing lipids. Oleosomes can be used in the preparation of various food products, such as creams, salad dressings, mayonnaise and emulsion. However, food products are always subjected to thermal processing, and therefore, the evaluation of the thermal stability of oleosomes is of great important. The present work aimed to understand the effect of soya bean oleosome-associated proteins (SOAPs) on the thermal stability of soya bean oleosome emulsion (SOE). SOE was thermally treated for 15 min at different temperatures of 65, 75, 85 and 95 °C. The confocal laser scanning microscope (CLSM) and Cryo-SEM of SOE, and as well as fluorescence spectroscopy, circular dichroism of SOAPs were investigated. The stability of SOE was significantly affected by thermal treatments, by modulating the conformational structures of SOAPs, while the composition changed slightly. The results of particle size, zeta potential and CLSM showed that thermal treatments caused aggregations of oleosomes especially at high temperatures (75–95 °C). Thermally treated oleosomes were observed to have a rough surface. Results of this work are useful for understanding the underlying mechanisms of SOAPs in maintaining the thermal stability of SOE.     

Total inactivation of lipoxygenase in whole soya bean by pulsed light and the effect of pulsed light on the chemical properties of soya milk produced from the treated soya beans

The inactivation of lipoxygenase (LOX) in the whole soya bean prevents lipid oxidation that produces an off‐flavour of soya food. The inactivation of lipoxygenase in the whole soya bean by pulsed light (PL) was examined with three distances (5, 7 and 9 cm) from the PL strobe and for different durations. Soya bean was treated with PL with and without ice surrounding the soya bean sample tray for limiting the rise in sample temperature. Results show that without ice surrounding the sample tray, the lowest LOX residual activity was 4.7%, 0.4% and 0.0% for 80‐s duration at 5 cm distance from the PL strobe, 110 s at 7 cm from the strobe and 150 s at 9 cm from the strobe, respectively; the soya bean temperature after treatment was 109.6, 116.3 and 114.8 °C, respectively. The instantaneous temperatures of the soya bean core measured during PL operating were above 100 °C. The lipoxygenase band was disappeared after longest PL treatments of each distance compared with the LOX band control as assessed by electrophoresis. The pulsed light had no negative effect on peroxide value of produced soya milk. However, PL reduced significantly the total solid amount and changed the colour of the produced soya milk. The residual activity with sample cooling by ice during treatment was 79.0%, 98.8% and 95.7%, with sample temperatures of 81.7, 91.2 and 66.9 °C, respectively. This study indicates that PL illumination could fully inactivate LOX in whole soya beans, with the photo‐thermal effect of PL as the main factor responsible for the inactivation of LOX.     

Response of intestinal proteinase activities to the feeding of isolated winged bean (Psophocarpus tetragonolobus) and soya bean (Glycine max) trypsin inhibitors in rats

The antinutritional activities of trypsin inhibitors (TIs) were compared between winged beans (Psophocarpus tetragonolobus) and soya beans (Glycine max). The inhibitors of the two beans were isolated by trypsin‐bound Sepharose 4B, and 50 mg of lyophilised powders were intubated intragastrically into 24 h fasted rats. The activities of trypsin and chymotrypsin were compared after 30, 60 and 180 min in the washings of the upper, middle and lower parts of the small intestine. The elution profiles of TI and non‐TI compounds in the affinity chromatography were similar in the two beans, and the antitryptic activities were concentrated 5.5 and 6.2 times (based on specific activity) for winged beans and soya beans respectively. Regardless of the TI fed to rats, trypsin activity in the upper intestine was suppressed to almost undetectable levels at 30 and 60 min after intubation. The activities in the middle and lower intestines were also substantially lowered when rats were fed winged bean TI, and significant differences were detected at 30 and 60 min after intubation when compared with rats fed soya bean TI. However, at 180 min after feeding, no differences were found in the trypsin activity in any gut segments. Similar inhibitory properties of isolated TIs were observed in chymotrypsin activities in the small intestine. The results suggest that winged bean TI may have greater inhibitory activity on the intestinal proteinase compared with soya bean TI. © 2001 Society of Chemical Industry     

Textural modification of soya bean/corn extrudates as affected by moisture content, screw speed and soya bean concentration

A Clextral BP‐10 (type BC45) co‐rotating twin‐screw extruder was used for texture modification of extrudates. Dry materials were mixed in a mixer for 15 min at low speed before extrusion. Moisture content 21–23% and addition of soya bean flour (0–40%) showed significant influences on the texture of the extrudates. Addition of soya bean flour in the range from 0 to 40% increased the diametrical expansion ratio (P < 0.01), decreased the hardness (P < 0.01) and modifies specific volume and chewing behaviours of the extrudates. Increasing moisture content in the range from 21 to 23%, however, significantly decreased specific volume (P < 0.01), and increases hardness (P < 0.01) of the extrudates. The hardness and crispness of the extrudates at fracturability of 110 g were graded higher than 6.0 by 30 and 27 of 34 consumer panelists, respectively. Consumer purchase intent showed the highest score of 5.5 in a 9‐point hedonic scale when sample fracturability was at 110 g.     

Optimisation of soya bean oil bleaching by ultrasonic processing and investigate the physico‐chemical properties of bleached soya bean oil

In this study, an ultrasonic bleaching method for soya bean oil under different conditions was optimised by monitoring the reduction of oil‐containing colourants. Ultrasonic power, clay content, temperature and time had a significant interaction effect on (P < 0.05) the reduction of oil pigments and colourants. Under optimised conditions, red and yellow colour indices in the ultrasound‐bleached soya bean oil reduced to 74.44% and 75.55%, and 54.18% and 58.85%, respectively, at amplitudes of 85% and 65%. Carotenoid and chlorophyll concentrations also reduced to 81.19% and 83.62%, and 94.66% and 95.26%, respectively, at 85% and 65% ultrasonic power. The overall contents of sterols and tocopherols decreased using ultrasonic bleaching process compared with the neutralised soya bean oil. Although the peroxide value (PV) of the soya bean oil after ultrasonic and control bleaching reduced, this index was higher in the ultrasonic bleached oil than the control one. The results showed that the ultrasonic bleaching process could be an alternative to the industrial bleaching method as it reduced clay usage, temperature and time of bleaching about 35%, 35% and 10%, respectively.     

黑豆脂肪酸成分的GC/MS分析

采用石油醚抽提黑豆油,用氢氧化钾-甲醇法脂化后进行GC/MS分析,确认出14种脂肪酸,所鉴定组分占总峰面积的99.05%,其中脂肪酸主要成分相对含量:棕榈酸(16.40%),亚油酸(47.59%),油酸(14.19%),亚麻酸(6.36%),硬脂酸(10.10%)。     

Within-plot and within-plant variation for seed content of soya bean protease inhibitors

Experiments were designed to determine the seed content of protease inhibitors in different plants of a plot or at different nodes along the main stem. The inhibitory activity of the samples was measured in vitro using sodium benzoyl-DL-arginine-p-nitroanilide as chromogenic substrate and bovine trypsin as target enzyme. Six soya bean (Glycine max Merr) strains were used, three capable of synthesizing the Kunitz trypsin inhibitor (L62-364, Williams 82, and 594-1) and three lacking this particular function (L81-4590, L81-4871, and L83-4387). In all genotypes on trial, remarkable plant-to-plant variation was found, so that most strains had at least one part of the data distribution in common. Significant differences were also noted for antitryptic activities of seed samples collected at different positions on the main stem. Gradients interior to the plant varied according to the tested strain but those of Williams 82 and of its near isogenic line L81-4590 were very similar, indicating that the amount and type of variation depended on genotype and that changes in the inhibitory activity were attributable to variation in the synthesis of inhibitors other than Kunitz.     

Trypsin inhibitory activity of raw soya bean after incubation with rumen fluid

Four soya bean (Glycine max Merr) inbreds, two of which (Williams 82 and Amsoy 71) capable of synthesising the Kunitz trypsin inhibitor (high trypsin inhibitory activity (TIA)) and two (L81–4590 and L83–4387), nearly isogenic to the former but lacking this particular function (low TIA) were used. In-vitro trials were performed to evaluate the residual TIA of flours incubated with runem fluid and the possible effect of proteinase inhibitors on rumen microbial fermentation, estimated by gas production. Only a slow fall in TIA was observed after short incubation times (5–10% at 2 h and 10–18% at 6 h), but after this period the rate of decline of TIA accelerated to give residual TIA of about 50% after 12 h and undetectable values after 48 h. Significant differences between genetic backgrounds were observed only at 2 h, when the Williams 82 background had a faster initial loss of TIA (89.1 versus 97.5% of the original activity, P < 0.01). Different patterns of TIA degradation were observed according to the presence/absence of the Kunitz inhibitor: inbreds lacking the Kunitz inhibitor initially had a higher residual TIA (95.9 versus 90.7%, P < 0.01) while at 12 and 24 h the residual TIA was considerably lower with respect to the other inbreds (45.4 versus 60.8 and 10.7 versus 20.4, respectively, P < 0.01). Gas production after 2 and 6 h of incubation was similar across treatments, whereas slightly but consistently more (P < 0.05) gas was produced at longer incubation times for inbreds lacking the Kunitz inhibitor. The results indicated that the proteinase inhibitors contained in raw soya bean are degraded at a much slower rate than previous nylon bag studies have suggested and that the presence of the Kunitz inhibitor leads to a higher residual TIA after rumen degradation and slightly lower microbial gas production.     

Structural and physicochemical properties of soya bean protein isolate/maltodextrin mixture and glycosylation conjugates

The effect of mixture and conjugation with maltodextrin (MD) in aqueous solution on the structural and physicochemical properties of soya bean protein isolate (SPI) was investigated. Although the mixing of MD would not change the distribution of secondary structure and tertiary conformation of SPI, the protein aggregation was promoted through hydrophobic interaction, which resulted in the decrease in solubility and the improvement of gel strength and water holding capacity (WHC) of SPI/MD mixture. However, glycosylation decreased α-helix and increased β-structure. The bathochromic shift of the fluorescence emission maximum wavelength for SPI/MD conjugates was promoted, resulting in less compact tertiary conformation. These structural modifications might be the reason for the changes in the physicochemical properties of conjugates. After glycosylation, the surface hydrophobicity and solubility were increased, the average particle size was decreased, and the gelation properties were weakened including gel strength and WHC.     

Extraction and physicochemical properties of soya bean protein and oil by a new reverse micelle system compared with other extraction methods

Reverse micelle extraction is a novel technology for the separation of plant components such as proteins and oil. In this study, sodium bis(2‐ethylhexyl) sulphosuccinate (AOT) reverse micelle system and AOT/Tween 85 reverse micelle system were used to extract soya bean protein and oil from soya bean flour. The physicochemical properties of the protein and oil extracted were investigated and compared with traditional extraction methods. The results showed that the efficiency of forward extraction of soya bean protein using an AOT/Tween 85 reverse micelle system was superior to that using an AOT reverse micelle system at the optimal extraction conditions. In addition, soya bean proteins extracted using reverse micelle extraction had no unordered structure under Fourier transform infrared spectroscopy. The acid and peroxide values of oil products from two reverse micelle extractions were lower than that from immersion. The results indicated that AOT/Tween 85 reverse micelle system is effective in extracting soya bean protein and oil.     

In vitro digestibility of processed and fermented soya bean,cowpea and maize

Tropical legumes, ie soya bean and cowpea, were pre‐treated and subsequently fermented using pure cultures of Rhizopus spp. Impact of soaking, cooking and fermentation of the legumes on their digestibility was determined using an in vitro digestion method. Processing of white maize included, amongst others, natural lactic acid fermentation, cooking and saccharification using barley malt. An in vitro method was standardised to carry out comparative determinations of the dry matter digestibility of cereal and legume food samples as a function of processing conditions, without attempting to exactly mimic gastrointestinal digestion. Using this method based on upper digestive tract digestion, it was observed that digestibility of the legumes increased during cooking and fermentation. Cooking improved the total digestibility of both soya bean and cowpea from 36.5 to 44.8% and from 15.4 to 40.9% respectively. Subsequent fungal fermentation increased total digestibility only by about 3% for both soya bean and cowpea. Digestibility was also influenced by fungal strain and fermentation time. Cooking and subsequent saccharification using malt almost tripled total digestibility of white maize from 25.5 to 63.6%, whereas lactic fermentation of maize had no effect on in vitro dry matter digestibility. Although total digestibility of cooked legumes was only slightly improved by mould fermentation (3% for both soya bean and cowpea), the level of water‐soluble dry matter of food samples increased during fermentation with Rhizopus oryzae from 7.0 up to 27.3% for soya bean and from 4.3 up to 24.1% for cowpea. These fermented products could therefore play a role as sources of easily available nutrients for individuals suffering from digestive disorders. © 2000 Society of Chemical Industry     

Effect of exogenous spermine on quality and sucrose metabolism of vegetable soya bean (Glycine max L.) during cold storage

Vegetable soya bean deteriorates quickly after harvest at ambient temperature due to loss of green colour and consequent yellowing of grains. To seek an effective method to control the postharvest quality, the effect of exogenous spermine on visual quality, sugar loss and sucrose‐metabolising enzyme activities of vegetable soya bean (Glycine max L.) during cold storage was investigated. The results showed that exogenous spermine (1.0 mmol L^?1) noticeably prolonged shelf life, inhibited the increase of weight loss and decay index and retained the colour. It also significantly minimised sucrose loss by regulating the activities of sucrose‐metabolising enzymes. Sucrose content negatively correlated with acid invertase (AI) activity at P < 0.05, while positively with sucrose phosphate synthase (SPS) activity at P < 0.01. There was no significant correlation with the activities of neutral invertase and sucrose synthase. These results indicated that the AI and SPS activities might play an important role in the control of sucrose metabolism resulting in reduction of sucrose loss.     

Physicochemical properties and storage stability of spray‐dried soya bean sprout extract

Amylase is a very important enzyme due to its wide food applications. To preserve amylase activity in soya bean sprout extract (SSE), SSEs were spray‐dried with 10% maltodextrin and 0–3% alginic acids, and their physicochemical properties and storage stability were compared with freeze‐dried one. SSE exhibited maximum amylase activity at pH 7.0 and 60 °C, with the most active substrate specificity towards soluble starch. Spray‐dried SSEs exhibited higher water solubility index (WSI) and in vitro relative amylase activity but lower water vapour sorption (WVS) and smaller particle size than freeze‐dried SSE. For spray‐dried SSEs, particle size, WSI and in vitro relative amylase activity increased while WVS decreased with increasing % alginic acid. This study demonstrated that spray drying of SSE, especially with 10% maltodextrin and 2% alginic acid, was effective in keeping amylase active and stable during 7‐week storage at room temperature (25 °C).     

Formation of lysinoalanine following alkaline processing of soya bean meal in relation to the degradability of protein in the rumen

Effects of sodium hydroxide (NaOH) treatment on the formation of lysinoalanine (LAL) and on in-situ and in-vivo utilisation of soya bean meal (SBM) protein were investigated. Defatted SBM was sprayed with 0 (water), 25, 50 and 100 g NaOH (kg^?1 dry matter), dried at 80°C for 2 h and then fed to four rumen cannulated goats in a 4 × 4 Latin square as a mixed diet (9: 1 w/w) of sudangrass hay and the SBM. LAL was not detected in non-alkaline SBM, but the cross-linked amino acid increased according to the level of NaOH addition. The maximum concentration of LAL was 1.26 g per 16 g nitrogen when the highest level of NaOH was applied. The NaOH treatment did not alter the digestibility or the retention of nitrogen of the mixed diet. Addition of NaOH at 25 and 50 g (kg^?1 dry matter) lowered the solubility of protein, while the highest level of treatment had little effect. Lag time and rate of degradation of protein decreased due to the increasing level in NaOH treatment. A significant correlation (r = —0.860, P < 0.01) between LAL content and rate of protein degradation suggested that the formation of cross-linked amino acid would render protein more resistant to microbial degradation in the rumen.     

Biochemical,textural and microstructural changes in whole‐soya bean cotyledon sufu during fermentation

This study aims to investigate the nutritional value of sufu and reduce environmental problems caused by okara, which results from the traditional processing method of sufu. The feasibility of the whole‐soya bean cotyledon sufu (WSCS) processing method, which does not produce okara, was investigated. WSCS was prepared by ripening okara‐containing tofu through various hydrolytic enzymes secreted by Actinomucor elegans for 70 days. After fermentation, total nitrogen, amino nitrogen and lipid contents were found to be lower in WSCS than in traditional sufu (TS), whereas contents of reducing sugar, dietary fibre, isoflavone aglycone and soya bean polysaccharide were higher in WSCS than in TS. The hardness, springiness and adhesiveness of WSCS were 249.703 ± 0.500 g, 0.606 ± 0.008 and 8.393 ± 0.032 J, respectively. The corresponding values for TS were 264.863 ± 0.572 g, 0.615 ± 0.007 and 7.516 ± 0.031 J, respectively. In addition, microstructural changes in WSCS and TS during fermentation were observed through scanning electron microscopy. The results from this study may provide a basis for industrial production of WSCS.