Effects of Acidified Processing and Storage on Proteins and Lipids in Mung Bean Sprouts

Fresh mung bean sprouts contained 5.3g protein/100g fresh weight which decreased slightly on blanching and on bottling and canning. Storage of bottled seedlings for 6 months at 35°C caused the largest loss in total protein. The protein contained the essential amino acids tryptophan, valine, leucine, phenylalanine, arginine, lysine and histidine. Total lipids of fresh mung bean sprouts were 350 mg/100g fresh weight and were not greatly affected by blanching nor by canning or bottling. When the bottled seedlings were stored at 10°C and at RT, the canned seedlings at RT, there was some effect on total lipids in that only bottled seedlings at 35°C showed a significant decrease in lipids. After storage at the three temperatures there were increases in glycolipids and decreases in phospholipids, due mainly to increases in monogalactosyldiglyceride and decreases in phosphatidic acid respectively.     

Development of microbiologically safe mung bean sprouts using combination treatment of sodium hypochlorite and gamma radiation

Specific group of people, with impaired immune system, are recommended to consume pathogen‐free foods. In this study, microbiologically safe ready‐to‐eat (RTE) mung bean sprouts were developed using combination treatment (CT) with 200 ppm sodium hypochlorite and 12 kGy dose of gamma radiation. Microbiological analysis of combination‐treated sprout samples showed complete elimination (<10 CFU g^?1 of sprouts) of microbial load in these samples, even during storage at 4 °C up to 12 days. Combination treatment and storage period did not have any significant effect on the sensory qualities of RTE mung bean sprouts. However, reduction in the firmness and vitamin C content of combination‐treated sprout samples, similar to other food processing methods, was observed. These results suggest that CT is effective in sterilisation of mung bean sprouts. These sprouts can be included in the diets of special target groups and thereby improve in their quality of life.     

Effects of probiotic L. plantarum 299v on consumer quality,accumulation of phenolics,antioxidant capacity and biochemical changes in legume sprouts

This study evaluated the influence of Lactobacillus plantarum 299v on the consumer quality of legume sprouts. The probiotic-rich sprouts were produced by soaking the seeds in probiotic water suspension and further sprouting at 25 °C for 4 days. The enrichment of the sprouts with L. plantarum 299v only slightly affected the sensory quality - the overall acceptability of the probiotic-rich sprouts was usually higher. The probiotic-rich sprouts exhibited increased activity of polyphenol oxidase (the highest activity in the mung bean preparations - 73.97 U mg⁻¹ of protein). The peroxidase activity was not altered. The probiotic enrichment increased the phenolic content by 25%, 31% and 23% in the soybean, adzuki and mung bean preparations; however, it was not reflected in the antioxidant activities. The changes in the activity of enzymes involved in mobilisation of stored material (starch and proteins) and the increased content of phenolics only slightly modified the bioavailability of nutrients.     

Irradiation to kill Escherichia coli O157:H7 and Salmonella on ready-to-eat radish and mung bean sprouts

A study was carried out to evaluate the effectiveness of ionizing radiation in eliminating Escherichia coli O157:H7 and Salmonella on commercial ready-to-eat radish and mung bean sprouts and to assess the chemical and physical quality of these sprouts. The use of ionizing radiation was investigated as a means of reducing or totally inactivating these pathogens, if present, on the sprouts. Treatment of mung bean and radish sprouts with a dose of 1.5 and 2.0 kGy, respectively, significantly reduced E. coli O157:H7 and Salmonella to nondetectable limits. The total vitamin C content was gradually reduced with the increase in irradiation dose (P < 0.0001). However, the effect of storage interval on the loss of vitamin C was nonsignificant for radish sprouts and significant for mung bean sprouts (P < 0.04). The color, firmness, and overall visual quality of the tested sprouts were acceptable when effective doses were applied to both radish and mung bean sprouts. Therefore, ionizing radiation could be useful in reducing the population of pathogens on sprouts and yet retain acceptable quality parameters.     

Assessment of phytochemicals,enzymatic and antioxidant activities in germinated mung bean (Vigna radiata L. Wilezek)

Vitamin C, phenolic and flavonoid contents along with enzymatic and antioxidant activities were determined in germinated mung bean (Vigna radiate). Elevated levels of vitamin C 72.31 ± 0.62 mg/100 g FW and flavonoid content 85.57 ± 0.59 mg CE/100 g FW were estimated for euphylla after 6 days of germination. Moreover, maximum peroxyl radical scavenging activity 645.4 ± 28.5 μmol ASA equiv./100 g FW was also determined in euphylla. However, seed coat has the highest content of phenolic content (568.4 ± 8.8 mg GAE/100 g FW), whereas cotyledon depicted the highest ascorbate oxidase and peroxidase activities (396.5 ± 4.0 and 548.4 ± 2.8 min^?1 g^?1 FW, respectively). These findings revealed that euphylla in mung bean sprouts is the most bioactive part with significant level of phytochemicals. Therefore, after germination of 6 days, euphylla is the main source of nutrition in mung bean sprouts.     

Effect of light,acidified processing and storage on carbohydrates and other nutrients in mung bean sprouts

Fresh 4-day-old etiolated mung bean seedlings were analysed for proteins, carbohydrates and lipids, and vitamins A and C. Exposure of the sprouts to artificial light for 24 h increased the content of most constituents, especially provitamin A. Changes in the composition of the seedlings after preservation and storage for 6 months were followed. The sprouts were either canned or bottled, and then kept at various storage temperatures, regardless of storage conditions, hydrolysis of complex carbohydrates took place. There is some evidence that the reducing sugars released during storage underwent a Maillard reaction, leading to browning of the sprouts.     

Kinetic study of the antioxidant compounds and antioxidant capacity during germination of Vigna radiata cv. emmerald, Glycinemax cv. jutro and Glycine max cv. merit

The purpose of this study was to determine the antioxidant capacity and the content of antioxidant compounds in raw mung bean seeds and sprouts (Vigna radiata cv. emmerald) germinated for 2, 3, 4, 5 and 7 days and of soybean seeds of Glycine max cv. jutro germinated for 2, 3 and 4 days and of Glycine max cv. merit germinated for 2, 3, 4, 5 and 6 days. Antioxidant compounds, such as vitamin C and E, total phenolic compounds and reduced glutathione (GSH) were studied. Antioxidant capacity was measured by superoxide dismutase-like activity (SOD-like activity), peroxyl radical-trapping capacity (PRTC), trolox equivalent antioxidant capacity (TEAC) and inhibition of lipid peroxidation in unilamellar liposomes of egg yolk phosphatidylcholine (PC). The results indicated that changes in the contents of vitamin C, vitamin E and GSH depended on the type of legume and germination conditions. Sprouts of mung bean and soybeans provided more total phenolic compounds than did raw seeds. The SOD-like activity increased after germination of mung bean seeds for 7 days, by 308%, while no change was observed in sprouts of Glycine max cv. jutro and an increase was observed after 5 and 6 days of germination (∼20%) in Glycine max cv. merit. PRTC and TEAC increased during the germination process and retentions of 28–70% and 11–14%, respectively, for soybean, and 248% and 61%, respectively, for mung bean were observed at the end of germination. The inhibition of lipid peroxidation increased by 389% in 5–7 days’ germination of Vigna radiata cv. emmerald sprouts, and 66% in Glycine max cv. merit sprouts whilst, in Glycine max cv. jutro, germination did not cause changes in lipid peroxidation inhibition. According to the results obtained in this study, germination of mung bean and soybean seeds is a good process for obtaining functional flours with greater antioxidant capacity and more antioxidant compounds than the raw legumes.     

Changes in the contents of carotenoids,phenolic compounds and vitamin C during technical processing and lyophilisation of red and yellow tomatoes

We present the results of the first study on the impact of thermal processing and lyophilisation on three major micronutrient families: carotenoids, total polyphenols and vitamin C in two different tomato cultivars: a red tomato (RT) and a yellow one (YT). Micronutrients were analysed in fresh tomatoes, tomato purée and lyophilised tomatoes. YT contained no lycopene, lower β-carotene, similar vitamin C and higher total polyphenol contents than RT. Processing did not affect the carotenoid content in RT, but significantly lowered β-carotene in YT and also the contents of total polyphenol and vitamin C in both cultivars. Lyophilisation lowered the carotenoid content in RT but not in YT; in contrast, the total polyphenol content was preserved in RT but lowered in YT, and the vitamin C content was not affected in both cultivars. These results provide new data on the effect of thermal processing and lyophilisation on the content of the three main families of micronutrients in red and yellow tomatoes.     

Effect of storage period on provitamin-A carotenoids retention in biofortified maize hybrids

Vitamin A-rich maize hybrids provide sustainable solutions to malnutrition. However, significant loss of carotenoids during storage reduces its efficacy. Grains of nine sub-tropically adapted crtRB1-based biofortified hybrids along with six normal hybrids were stored under conventional storage for five months. PVAC (β-carotene and β-cryptoxanthin) among crtRB1-based hybrids degraded from initial level of 18.77 to 3.24 µg g⁻¹, while NPVAC (lutein and zeaxanthin) reduced to 10.79 µg g⁻¹ from 19.00 µg g⁻¹ during storage. Among PVAC, β-cryptoxanthin (21.8%) possessed more stability than β-carotene (16.4%). For NPVAC, lutein (61.2%) showed the highest retention than zeaxanthin (50.4%). Majority of the PVAC loss occurred within first three months of storage. Retention for PVAC among crtRB1-based hybrids varied from 14% to 23% indicating the role of favourable genetic factors. APQH1, APQH7 and APH2 were the promising hybrids with higher retention (>20%) of PVAC. This is the first report on identification of provitamin A-rich crtRB1-based biofortified maize hybrids with higher retention during sub-tropical storage.     

Cagaita (Eugenia dysenterica DC.) of the Cerrado of Minas Gerais, Brazil: Physical and chemical characterization, carotenoids and vitamins

The physical characteristics (diameters, height and mass), chemical composition (tritratable acidity, soluble solids, pH, moisture, ash, protein, lipids and total dietary fiber), occurrence and content of vitamin C (ascorbic acid and dehydroascorbic acid), carotenoids (??-carotene, ??-carotene, ??-cryptoxanthin and lycopene), vitamin E (??-, ??-, ??- and ??-tocopherol and tocotrienol) and folates (tetrahydrofolate, 5-methyltetrahydrofolate and 5-formyltetrahydrofolate) were evaluated in the cagaita obtained from the Cerrado of Minas Gerais, Brazil. The analyses of vitamin C and carotenoids were performed by HPLC-DAD and vitamin E and folates by HPLC with fluorescence detection. The cagaita pulp presented high content of moisture (91.56 g 100 g^− 1), vitamin C (34.11 mg 100 g^− 1) and folates (25.74 ??g 100 g^− 1). The presence of protein (0.63 g 100 g^− 1), ash (0.18 g 100 g^− 1), lipids (0.57 g 100 g^− 1), carbohydrates (5.54 g 100 g^− 1), dietary fiber (1.54 g 100 g^− 1) and carotenoids (0.77 mg 100 g^− 1) was observed in its composition. Vitamin E isomers were not detected. Consumption of cagaita (100 g) contributed significantly to supply the daily requirements of vitamin C (on average 71.0%), vitamin A (on average 7.5%) and folates (on average 7.9%). The cagaita showed high pulp yield, reduced total energy value and was considered a source of vitamin C, which play important role in human health.     

Effect of UV‐B treatment during the growth process on the postharvest quality of mung bean sprouts (Vigna radiata)

The production patterns and nutritious qualities of mung bean sprouts are in line with the consumption needs of modern people. This study was conducted to explore the effects of low doses of UV‐B irradiation on the 3‐day growth period of mung bean sprouts. The results showed that, when mung bean sprouts were irradiated with UV‐B (0.738 kJ m^?2) for 1 h per day, their total phenolic content increased by 22.80%, and the activity of polyphenol oxidase decreased by 45.45%. Hypocotyl epidermis stomata were closed, reducing water loss and the opportunity for microbes to invade plants, leading to the maintenance of freshness of the sprouts. In conclusion, UV‐B irradiation for 1 h per day during the growth of mung bean sprouts can effectively improve their preservation. This method is a low‐cost, environmental friendly and pollution‐free physical preservation technique, and it has good application prospects.     

Changes in individual carotenoids on processing and storage of mango (Mangifera indica) slices and purée

Susceptibility of different carotenoids to degradation during thermal processing and storage of two mango cultivars was investigated. The carotenoid composition was practically maintained on processing mango (cultivar Tommy Atkins) slices. The only significant change was the increase in luteoxanthin, compatible with the conversion of 5,6- to 5,8-epoxide. More evident transformations occurred on processing mango (cultivar Golden) purée. The major pigment β-carotene decreased 13%, resulting in a corresponding reduction of the vitamin A value. Auroxanthin, not found in the fresh fruit, appeared while violaxanthin and luteoxanthin decreased. During storage of mango slices in lacquered (epoxy) or plain tin-plate cans, no appreciable loss of β-carotene was observed during 10 months. Between the tenth and fourteenth month, about 50% reduction of β-carotene occurred. The degradation continued, resulting in a total loss of 84% after 24 months. A tendency of violaxanthin to decrease, and auroxanthin to increase, during storage was also noted. β-carotene showed a greater susceptibility to degrade in bottled mango purée (18% loss after 10 months) than in the canned product. As in the case of mango slices, however, both bottled and canned purée suffered 50% loss of β-carotene after the tenth month, and a total loss of 83% after 24 months. Violaxanthin and luteoxanthin tended to decrease while auroxanthin maintained a comparatively high level throughout storage. The vitamin A values reflected the degradation trend of β-carotene, a pattern that appears to agree with a free radical mechanism.     

气流超微粉碎对绿豆芽物理特性与抗氧化活性的影响

以经干燥处理后的绿豆芽为原料,比较经气流超微粉碎处理后绿豆芽多酚提取量、抗氧化活性及物理特性的变化。结果表明:气流超微粉碎的最佳条件为压力0.5 MPa,转速5 000 r/min。与常规粉碎相比,绿豆芽多酚提取量提高了10.74%,除DPPH自由基清除能力下降外,绿豆芽多酚对ABTS+自由基及羟自由基的清除能力分别提高了2.8%,13.2%;水含量、水活度、粒径大小明显减小,比表面积、溶解度及堆积密度均有提高,表明气流超微粉碎在一定程度上提高了绿豆芽粉的有效利用率。     

A modified laboratory canning protocol for quality evaluation of dry bean (Phaseolus vulgaris L)

The effects of calcium (Ca²⁺) level in the soak water, blanch water and brine, blanching temperature, and total seed solids on dry bean canning quality were investigated to optimise a laboratory canning protocol. A linear increase in the Ca²⁺ level of soak water, blanch water and brine resulted in a linear decrease in hydration coefficient and percent washed drained weight but a linear increase in texture. Low Ca²⁺ level (10 mg kg⁻¹) reduced the hydration time for dry bean seed from 14 to 1 h. Blanching temperatures of 50, 70 and 88 °C had non‐significant effects on canning quality traits. Blanching for 30 min at 70 °C for black bean or at 88 °C for navy bean and pinto bean resulted in percent washed drained weight ≥ 60, as required by the Canada Agricultural Products Standards Act. Seed solids levels of 95–97 g per 300 × 407 (14 fl oz) can were sufficient to attain a percent washed drained weight of 60. It was confirmed that the thermal processing conditions (115.6 °C retort temperature, 45 min) used in this study were sufficient to achieve commercial sterility. The optimised lab protocol for evaluation of the canning quality of dry bean breeding lines is as follows. Seed containing 95 g of solids for pinto bean, 96 g for navy bean and 97 g for black bean is soaked in water for 30 min at 20 °C and blanched for 30 min at 70 °C for black bean and 88 °C for navy bean and pinto bean in water containing 10 mg kg⁻¹ of Ca²⁺. The seed is then transferred to a 300 × 407 can, filled with brine containing 10 mg kg⁻¹ of Ca²⁺, 1.3% (w/v) of NaCl and 1.6% (w/v) of sugar. The can is then sealed, processed in steam at 115.6 °C for 45 min and cooled at 20 °C for 20 min. Cans are stored for at least 2 weeks prior to quality evaluation of the canned product. Canning of dry bean seed according to this protocol results in precise estimation of canning quality traits, particularly percent washed drained weight. © 2000 Society of Chemical Industry     

Effect of processing variables on the stability of β-Carotenes and xanthophylls of dehydrated parsley

Curled- and plain-leaf parsley were analysed for β-carotene, xanthophyll and the stereo-isomers of β-carotene, before and after various combinations of freezing, blanching, sulphiting and air-drying. Heating of parsley by blanching or by dehydration of unblanched samples generally resulted in an increased retention of β-carotene. Dried samples contained a higher percentage of the cis-isomer and neo-β-carotene b but a lower percentage of the all-trans-isomer. Freezing unblanched parsley reduced total carotene content 8–13 %. Xanthophyll changes were similar to those for total carotene except that dried samples contained 2–28 % less xanthophyll than fresh parsley. Sulphited samples retained 8–30 % more carotenoid pigments than the non-sulphited samples. Total β-carotene of dried parsley stored for 3 months in air and in nitrogen at 22° decreased 10-15%and 3·5-10%, respectively, while that stored at –18° showed no change. The stereo-isomer ratio did not change. Blanching had no apparent effect on carotene stability in storage. Carotene loss in fresh parsley, additional extractions, and enzymic destruction of added carotene were also investigated.     

Effect of plasma-activated water on microbial quality and physicochemical characteristics of mung bean sprouts

The efficacy of nonthermal plasma-activated water (PAW) in the decontamination of mung bean sprouts was evaluated in this work. After being treated with PAW for 30 min, the populations of total aerobic bacteria and total yeasts and moulds on mung bean sprouts were decreased by 2.32- and 2.84- log₁₀ CFU/g, respectively. The PAW treatment had no significant effect on the antioxidant potential of mung bean sprouts as shown by using 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH•) scavenging activity assay, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method, and ferric reducing antioxidant power (FRAP) assay (p > 0.05). Additionally, the PAW treatment caused no significant changes in the total phenolic and flavonoid contents, nor the sensory characteristics of mung bean sprouts (p > 0.05). Reactive species such as nitrates, nitrites, and H₂O₂ were generated in PAW, which presumably contributed to the disinfection efficacy of PAW. These data show that PAW can be used as a promising nonthermal technology for the control of microbial contamination in sprouts.Industrial relevanceEdible sprouts are common food ingredients across the world. However, sprouts can be contaminated by pathogenic microorganisms, which may result in health risks to humans. Recently, PAW has been shown to be a safe and effective method for food surface sanitation. However, the application of PAW in the microbial control for sprouts is less investigated. In this study, the influences of PAW on the microbial load, chemical and sensory quality of mung bean sprouts were investigated for the first time. The results showed that PAW could effectively inactivate bacteria and yeasts and moulds on mung bean sprouts without resulting in significant changes in the antioxidant capacities, total phenolic and flavonoid contents, and sensory characteristics of mung bean sprouts. These data indicated that PAW can be used as a promising nonthermal technology for reducing microbial populations on sprouts.     

Effect of freezing and canning on the content of selected vitamins and pigments in seeds of two grass pea (Lathyrus sativus L.) cultivars at the not fully mature stage

Seeds of the grass pea (Lathyrus sativus L.) cultivars Derek and Krab, with a dry matter content of about 33%, were used for freezing and for canning. The content of vitamins C, B1, and B2 and of carotenoids, beta-carotene, and chlorophylls was determined in raw and blanched material, in frozen products after 6-month storage before and after cooking to consumption consistency, and in canned products after 6-month storage. In comparison with the cultivar Krab, raw seeds of Derek contained 45% more vitamin C, 14% more total chlorophylls, 13% less thiamine (vitamin B1), and 7% less riboflavin (vitamin B2). The level of carotenoids was similar. Blanching of seeds led to a statistically significant decrease only in the content of vitamin C. Freezing and frozen storage significantly lowered the level of vitamin C and chlorophylls. The cooking of frozen seeds and the production of canned products and their storage resulted in a statistically verified reduction in the content of components analysed in all the samples. Greater losses were found in products prepared from seeds of the cv. Krab. After cooking, frozen seeds contained more of all the analysed components than the canned products.     

Folacin content of alfalfa and mung bean sprouts: The effect of extraction procedures and maturity

The folacin content of alfalfa (Medicago sativa) and mung bean (Vigna radiata) sprouts was determined by Lactobacillus casei. Several variations of extraction procedures were tested. The optimum conditions for extraction were autoclaving mung bean and alfalfa sprouts in phosphate buffer containing 0.3% and 0.4% ascorbate, respectively, before homogenisation in a blender. The optimum blending time for folacin extraction was 120s for mung bean and 15s for alfalfa sprouts. Folacin content on dry weight basis increased several times in both types of sprouts during germination. Mature alfalfa and mung bean sprouts were found to contain 186 and 178 μg folacin per 100 g fresh weight, respectively.     

Comparative analyses of total phenols,flavonoids, saponins and antioxidant activity in yellow soy beans and mung beans

Total phenol, flavonoid and saponin content of soy bean and mung bean were systemically compared in order to evaluate their contribution to overall antioxidant activity. Mung bean extract possessed significantly higher total phenol (2.03 GAE g^?1 vs. 1.13 GAE g^?1) and flavonoid contents (1.49 GAE g^?1 vs. 0.41 CAE g^?1) than soy bean extract, while the saponin content of the soy beans was 4.5 times greater than that of the mung beans. In several antioxidant assays including DPPH and ABTS radical scavenging, FRAP, SOD‐like activity, and a β‐carotene bleaching assay, mung bean extract consistently showed significantly greater antioxidant activity than soy bean extract. The specific antioxidant activity, which was evaluated at the same phenolic content suggested that the phenolic compounds present in the mung bean extract were not only of greater quantity but also had better quality to eliminate radicals. The radical scavenging activities of saponins were only marginal.     

Attachment and Biofilm Formation by Selected Strains of Salmonella enterica and Entrohemorrhagic Escherichia coli of Fresh Produce Origin

This study compared the abilities of selected Salmonella enterica and enterohemorrhagic Escherichia coli (EHEC) strains of fresh produce origin to form biofilms on polystyrene surface and to attach to alfalfa and bean sprouts. Each of the 7 S. enterica and 4 EHEC inocula (2 mL; 10⁷ CFU/mL) was placed in 6 different broths in 24‐well polystyrene tissue culture plates at 28 °C for 1 to 7 d. Developed biofilms were quantified using the crystal violet binding assay. In a separate experiment, alfalfa and mung bean sprouts (5 g) were exposed to 25 mL inocula (10⁷ CFU/mL) of S. enterica or EHEC at 22 °C for 2 h with shaking at 40 rpm. Contaminated sprouts were thoroughly rinsed and homogenized in 0.1% peptone water, and bacteria attached to sprouts were enumerated. Biofilm mass accumulated on polystyrene surface increased with incubation time (P < 0.05). Among the microbiological media used, LB no salt (NaCl) broth better supported biofilm development (P < 0.05). Two EHEC strains formed more biofilms than the Salmonella and other two EHEC strains (P < 0.05). However, more Salmonella cells (5.66 log CFU/g) attached to sprouts than EHEC cells (3.46 log CFU/g). Both Salmonella and EHEC attached in higher numbers to mung bean, than alfalfa, sprouts (P < 0.05).