Thermal stability of black turtle soup bean (Phaseolus vulgaris) lectins

A method for determining the thermal stability of porcine thyroglobulin (PTG)-binding lectins in whole black turtle soup beans (Phaseolus vulgaris L) is described. The procedure utilises PTG-Sepharose affinity chromatography and the Folin-Ciocalteau protein assay. The majority of lectin activity in whole black turtle soup beans was destroyed by heating presoaked beans at 97.8°C for 10 min whereas unsoaked beans required 20 min of heat treatment at 97.8°C. Residual lectin activity was eliminated by thermally processing the presoaked and unsoaked beans for 25 and 50 min at 97.8°C, respectively. Thermal inactivation of the lectin in the whole seed is a biphasic, first-order reaction mechanism. Lectin-rat intestinal epithelial cell binding studies indicated the presence of a second lectin in the BTS albumin protein fraction. The lectin lacked an affinity for PTG and was inactivated by heating unsoaked whole beans for 50 min at 97.8°C.     

蜜渍红豆的研制

红豆经过烧煮、浸泡、豆类软化剂处理和果葡糖浆的蜜渍,生产出的蜜渍红豆加至雪糕、冰淇淋中具有良好的抗冻性能,在-15℃时保持较好的柔软性和韧性。     

Sorption of propylene oxide by various commodities

Sorption of propylene oxide (PPO) by various commodities was studied at different concentrations during a 4-h exposure at 30 °C. A gas chromatograph was used to determine sorption of PPO applied at concentrations of 24, 49, 82 and 112 mg/l by 1±0.01 kg of narcissus bulbs, wheat, corn and cocoa beans in 2.64-l fumigation chambers. Results showed that for corn and cocoa beans the decrease in concentration during the first hour, that ranged from 40% to 76% of the initial concentration applied, was much greater than that for narcissus bulbs and wheat, which ranged from 25% to 41% of the initial concentration applied. PPO was initially taken up faster by corn and cocoa beans than by narcissus bulbs and wheat. The average sorption rate for each commodity increased with increasing initial concentration. The average sorption rate of PPO by corn and cocoa beans ranged from 14.9 to 48.6 ((mg/kg)/h) which was higher at each concentration than sorption by narcissus bulbs and wheat. In spite of the relatively high rates of sorption, the PPO residues among wheat, corn and cocoa beans immediately following a 4-h fumigation were well below the 300 ppm tolerance. These data show that PPO rapidly desorbed from the commodities under fumigation at 30 °C and at ambient atmospheric pressure.     

Effect of Temperature on Properties of Extrudates from High Starch Fractions of Navy, Pinto and Garbanzo Beans

High starch fraction (HSF) isolated from three legumes were extruded at different temperatures. Extruded products were evaluated for expansion, density, color and some functional properties. The highest value of expansion was noted for pinto bean, and the lowest for garbanzo, extruded at 132°C. Extrudates from HSF expanded significantly (P < 0.05) less than corn extrudates. Oil absorption capacity increased slightly with increasing temperature and values were lower for navy and garbanzo beans than for pinto HSF and corn. Oil emul-sification capacity of- bean samples was about two times higher compared to corn. Water absorption index (WAI) of pinto and navy beans significantly increased (P < 0.05) from 110°C to 132°C.     

Starch–fenugreek (Trigonella foenum-graecum L.) polysaccharide interactions in pure and soup systems

The effect of replacement of varying levels of a fenugreek polysaccharide (FP) product (0.1–0.9%) on 5% wt/wt corn starch cream soups and pure starch systems was investigated. Pasting, textural and viscoelastic characteristics along with granule size and sensory properties were determined. Significant changes were revealed with increasing FP replacement, with the effects being more pronounced on the soup formulations compared to the effects on pure starch/fenugreek systems.     

Variations of volatile flavour compounds in Cordyceps militaris chicken soup after enzymolysis pretreatment by SPME combined with GC-MS,GC × GC-TOF MS and GC-IMS

Cordyceps militaris chicken soup has always been one of the most popular Chinese-style soups due to its high nutritional value and special flavour. In the present work, C. militaris chicken soup was stewed after enzymolysis pretreatment. Several advanced techniques including GC-MS, GC × GC-TOF MS and GC-IMS were utilised to investigate the volatiles of as-prepared C. militaris chicken soup. GC-MS and GC  ×GC-TOF MS analysis indicated that contents and kinds of the main compounds especially aldehydes and esters which have fatty and sweet aroma in C. militaris chicken soup were increased after enzymolysis process. GC-IMS results demonstrated that some volatile substances in chicken soup disappeared with the addition of C. militaris and concentrations of some volatile substances were increased after enzymolysis process. Enzymolysis pretreatment was confirmed to be an effective way to enhance the soluble protein dissolution rate and volatile flavour compounds of C. militaris chicken soup.     

Incidence of Listeria monocytogenes in Market Samples of Fresh and Frozen Vegetables

Samples of the outer portions of fresh beets, broccoli, cabbage, carrots, cauliflower, corn, head lettuce, leaf lettuce, mushrooms, and potatoes, as well as frozen green beans, green peas, pea pods, and spinach were examined for the presence of Listeria monocytogenes using a 7-day enrichment procedure at 30°C. Samples were streaked on modified McBrides agar, and isolates were tested for characterization reactions. Fresh carrots, lettuce, and mushrooms, and frozen spinach were also examined using a cold enrichment procedure at 4°C. Samples were taken weekly, streaked onto modified McBrides agar, and were characterized. It was determined that no L. monocytogenes was detectable in any of these samples.     

Effects of Vacuum Hydration on the Incidence of Splits in Canned Kidney Beans (Phaseolus vulgaris)

Dry red kidney beans were canned using two different pretreatments: soaking for 12 hr at 20°C, and vacuum hydration for 5 min followed by soaking for 2 hr at temperatures from 45-59.1°C. Samples were then packed, processed to commercial sterility, and tested for percentage of split beans after processing. Vacuum hydration pretreatments greatly decreased the incidence and severity of splitting in the canned product and accelerated water uptake while retaining the same moisture content after soaking as the conventional soak treatment. Vacuum-hydrated beans gained less moisture during retorting than conventionally treated samples.     

Isolation and Characterization of Adzuki Bean (Vigna angularis cv Takara) Starch

Starch was isolated from Minnesota-grown adzuki beans (Vigna angularis, cv Takara). The relatively low yield (21.5%) may be characteristic of the isolation method [and may well represent the practical limits for starch recovery for this extraction procedure]. Starch granules were oval to kidney shaped, with mean size 32 μm (range 15-45 μm). SEM micrographs revealed presence of deep surface fissures. Gelatinization temperature range was 64-66-68°C and amylose content was 28.8%. Gardner color values were L = 92.5, a = 0.0, b = 5.6. Starch showed low swelling power and solubility in water. Brabender viscosity patterns showed neither peaks nor breakdown of hot paste. Starch formed stable gels at 5% and higher concentrations; gel strength was similar to that of corn and wheat starch gels, but was definitely stronger than that of potato starch. Retrogradation was greater than in corn or wheat starch gels.     

Development of shelf stable pepper based appetizers by response surface methodology (RSM)

The paper deals with three pepper-based appetizers developed in the form of convenient beverage mixes. The optimization of ingredients in the formulations of spiced drink mix, spiced tomato mix and chakota soup mix was achieved using response surface methodology with statistical design software. The active ingredient pepper was 1.5 and 2.8/100 g as black pepper and 9/100 g as white pepper with total pungency (expressed as piperine, g/100 g) of 0.08, 0.155, 0.155 in spiced drink mix, chakota soup mix and spiced tomato mix, respectively. The appetizer mixes packed in paper/Al foil/ polythene (PFP) and polypropylene (PP) pouches were stored at ambient temperature as well as 37 °C. Periodic evaluation (2-months interval) revealed that spice drink mix and spiced tomato mix had a shelf life of 6 months, while it was 8 months for chakota soup mix packed in PFP pouches under ambient conditions (18-33 °C).     

Folate content in processed legume foods commonly consumed in Egypt

Industrial food processing and household cooking are reported to affect folate content. This study examined the effects of industrial and household processing methods on folate content in traditional Egyptian foods from faba beans (Vicia faba) and chickpeas (Cicer arietinum). Overnight soaking increased folate content by ∼40–60%. Industrial canning including soaking, blanching and retorting did not affect folate content (p = 0.11) in faba beans, but resulted in losses of ∼24% (p = 0.0005) in chickpeas. Germination increased folate content 0.4–2.4-fold. Household preparation increased the folate content in germinated faba bean soup (nabet soup) one-fold and in bean stew (foul) by 20% (p < 0.0001). After deep-frying of falafel balls made from soaked faba bean paste, losses of 10% (p = 0.2932) compared with the raw faba beans were observed. The folate content (fresh weight) in the traditional Egyptian foods foul and falafel and in the beans in nabet soup was 30 ± 2, 45 ± 2 and 56 ± 6 μg/100 g, respectively. The traditional Egyptian foods foul, falafel and nabet soup are good folate sources and techniques like germination and soaking, which increase the folate content, can therefore be recommended.     

Characterization of Extruded Blends of Corn and Beans (Phaseolus Vulgaris) Cultivars: Peruano and Black-Querétaro under Different Extrusion Conditions

The effect of extrusion conditions in blends of corn and beans (Phaseolus vulgaris) of cultivars Peruano and black-Querétaro were investigated in this study, as an alternative to obtain snack foods. The type of cultivar and beans percentage, and also the extrusion conditions (moisture and temperature) influenced the physicochemical (color and breaking strength) and the functional (water absorption index, water solubility index, and oil absorption capacity) properties of the extrudates. The microstructures showed the presence of cavities and starch granules gelatinized (melted) and plasticized; while, the x-ray powder diffraction patterns revealed the presence of monohydrate glucose due to starch dextrinization. The results demonstrate that extrudates with good properties can be obtained from blends of corn and beans, under selected extrusion conditions, depending on the bean cultivar.     

Skin improvement and stability of Echinacea purpurea dermatological formulations

Echinacea purpurea contains many beneficial constituents for protection of skin from oxidative stress and for improving hydration of skin. This study aimed to investigate the stability and dermatological efficacy of E. purpurea cream and gel. Echinacea purpurea extract was incorporated into suitable cream and gel bases. Stability of the extract in the formulations was investigated by determining its residual total phenolic content and antioxidant activity after storage at 4°C, 30°C and 40°C for 6 months. The effect of those formulations on skin irritation, hydration level and wrinkle reduction was evaluated in 10 healthy volunteers, aged 25–40 years. The shelf lives of E. purpurea cream and gel in terms of total phenolic content and antioxidant activity were only 2 and 4 months respectively at 4°C and could be extended up to 7 months by incorporation of α‐tocopherol or disodium editate. The corneometer hydration indices increased up to 10.6 AU and 11.4 AU, and the wrinkles decreased 9.47% and 14.92% because of the application of E. purpurea cream and gel for 1 month. Both formulations showed no irritation to skin. Echinacea purpurea cream and gel developed in this study were effective in improving skin hydration and reducing wrinkle, but showed low storage stability.     

负氧化还原电位电解水冷泡绿茶茶汤理化特性、抗氧化性能及香气成分研究

以瓶装饮用天然水冷泡绿茶和常规热泡绿茶作为对比,探讨负氧化还原电位电解水对冷泡绿茶茶汤品质的影响,以期为得到活性成分含量高及抗氧化活性强的冷泡绿茶饮品提供新选择。通过调节电解饮用水时间电解生成不同负氧化还原电位电解水1和2;通过紫外分光光度法、高效液相色谱法以及顶空固相微萃取与气相色谱-质谱联用法测定并比较负氧化还原电位电解水、瓶装饮用天然水冷泡绿茶和常规热泡绿茶茶汤基本理化指标、主要活性成分含量、抗氧化性、感官品质和香气成分。结果表明,负氧化还原电位电解水冷泡绿茶茶汤pH呈弱碱性,氧化还原电位为负值,可溶性固形物含量及茶汤浸提率显著高于瓶装饮用天然水冷泡绿茶（P<0.05）,与常规热泡茶相当;电解水制得茶汤色度黄绿明亮,汤色品质高;电解水茶汤多酚含量显著高于瓶装饮用天然水冷泡,且电解水样2显著高于常规热泡（P<0.05）,游离氨基酸总量显著高于瓶装饮用天然水冷泡以及常规热泡（P<0.05）,咖啡碱含量低于常规热泡,儿茶素类含量均高于瓶装饮用天然水冷泡,除EGCG和EGC外均高于常规热泡;电解水冷泡茶茶汤抗氧化能力显著高于其他两种绿茶茶汤（P<0.05）;电解水冷泡茶汤感官评分最高且茶汤香气成分最为丰富醇和。实验初步验证了负氧化还原电位电解水用作冷泡绿茶加工用水可行性,且筛选出电解水样2制得绿茶茶汤生化成分高、抗氧化活性强且感官评价得分高、香气清香持久。     

Development of a mushroom-whey soup powder

Summary Mushroom‐whey soup powder was prepared by cooking mushroom with concentrated cheese whey and blending. The seasonings (onion, garlic and ginger) were fried separately in hydrogenated fat, and cornflour was added if thickening was desirable. After the addition of salt and a further quantity of concentrated whey, the soup mix was again blended. It was then spray‐dried to produce a mushroom‐whey soup powder. The physico‐chemical properties of the soup powder, such as moisture content, loose and packed bulk density, wettability, insolubility index, thiobarbituric acid and hydroxy methyl furfural content, increased during storage. However, dispersibility and reflectance value decreased during storage. The soup powder reconstituted well when boiled in water for 2 min. The reconstituted soup was considered acceptable, with an overall acceptability score of 7.1 on a nine‐point hedonic scale, after 8 months of storage of the soup powder at 30 °C when packed in metalized polyester.     

Determination of Lactose and Sucrose Contents of Ice Cream Mix via Enzymatic-Cryoscopic Methodology

A simple method was developed for determining the lactose and sucrose contents of ice cream mix. The method is based on measuring the freezing point depression resulting from incubating samples with invertase (EC 3.2.1.26) and β-galactosidase (EC 3.2.1.23). Sucrose and lactose concentrations are determined separately with each determination requiring 50 units of enzyme and 2 hr of incubation at 37°C. A standard curve for lactose determination was obtained using ice cream mixes containing various amounts of sucrose and corn syrup solids (R²= 0.996, C.V. = 1.2%). A standard curve for sucrose determination was obtained using ice cream mixes containing various amounts of lactose and corn syrup solids (R²= 0.996, C.V. = 1.9%).     

底物面汤对蒲公英浆水品质的影响

为丰富浆水的种类、口感及功能,分别以豌豆、小麦及玉米面汤作为发酵原料,以蒲公英浆水发酵过程中pH、还原糖、总酸及发酵结束后氨基酸含量和挥发性风味物质为评价指标,探究三种面汤对蒲公英浆水发酵及风味的影响。结果显示:小麦面汤浆水与豌豆面汤浆水总酸含量接近,二者发酵速度及总酸含量均优于玉米面汤浆水。发酵后豌豆、小麦及玉米面汤浆水中分别含16、14、12种氨基酸,含量分别为12.890、5.700和2.191 mg/100 mL。分别含有挥发性物质28、28、27种,4-萜品醇、α-萜品醇、柠檬烯是三种浆水含量最高的挥发性物质,其它物质含量差异较大。感官评价表明,相比于小麦面汤和玉米面汤,豌豆面汤更有利于蒲公英浆水快速发酵及呈味,更能被消费者接受。     

Promoting Lactobacillus casei and Bifidobacterium adolescentis survival by microencapsulation with different starches and chitosan and poly L‐lysine coatings in ice cream

In this research, microencapsulation of the probiotics Lactobacillus casei ATCC 39392 and Bifidobacterium adolescentis ATCC 15703 was performed using calcium alginate, wheat, rice, and high‐amylose corn (Hylon VII) starches along with chitosan and poly L‐lysine coatings. The effect of microencapsulation on the survival and sensory properties of ice cream over 100 days at ?30 °C was evaluated. Scanning electron and optical microscopy were employed to measure capsule size and morphology. The results suggested that the survival of probiotics is increased by microencapsulation. Coating the capsules with chitosan and poly L‐lysine led to enhanced bacterial viability and an increase in the size of microcapsules. Among different starches, Hylon starch enhanced the survival of probiotics at low temperatures the most. Furthermore, the addition of probiotics in free and encapsulated states did not have a significant effect on the sensory properties, or pH levels of the final product during storage (p > .05).

Practical applications

Microencapsulation using various hydrocolloids is a commonly used method for enhancing probiotic survival in ice cream during the frozen storage. This study indicates that the microencapsulation of probiotics can enhance probiotic survival in ice cream after 100 days of storage at ?30 °C. Chitosan and poly L‐lysine coatings significantly improved the survival of encapsulated probiotics during the storage of ice cream. This improvement is attributed to the role of Hylon starch in creating more integrated microcapsule structure. Moreover, sensory evaluation of ice cream revealed that inoculation with the probiotic culture, in either the encapsulated or the free‐state, had no significant effect on texture, color, flavor, taste, or general sensory characterization of ice cream during the storage period at ?30 °C (p > .05).     

Yield and Quality of Tofu as Affected by Soybean and Soymilk Characteristics: Glucono-delta-lactone Coagulant

Nine light hilum soybean [Glycine max (L.) Merr] cultivars were used to study characteristics that affect yield and quality of tofu (soybean curd) coagulated with glucono-delta-lactone (GDL). Pressed and packed (nonpressed) curds were examined. Yield of tofu was not affected by size of beans. Protein and total solids in soymilk increased when protein and moisture increased in soybeans. Yield of pressed GDL tofu increased with protein content of soybeans (or soymilk) plus decreased calcium content. Fracturability of pressed GDL tofu increased with levels of phosphorus. Hardness of packed tofu increased with protein content in soymilk. Yield of pressed GDL tofu was 20% higher than CaSO₄ tofu.