Carbohydrates in raw and germinated seeds from mung bean and chick pea

The contents of hydrophilic extractives, lipids, protein, starch, non-starch polysaccharides, Klason lignin and ash were determined in raw and germinated seeds of mung bean (Phaseolus aureus) and chick pea (Cicer arietinum). Several low molecular weight carbohydrates were found in the hydrophilic extractives. During germination, due mainly to their use as an easily available source of germinating energy, there was a rapid decrease of the raffinose family oligosaccharides in mung bean and a somewhat slower decrease in chick pea. Changes in the content and composition of dietary fibres during germination was small.     

Changes in vitamin C content and antioxidant capacity of raw and germinated cowpea (Vigna sinensis var. carilla) seeds induced by high pressure treatment

The effect of high pressure treatment on the vitamin C content and antioxidant capacity of raw and germinated cowpea seeds (Vigna sinensis var. carilla) at 300, 400 and 500 MPa for 15 min at room temperature has been investigated. A considerable amount of vitamin C was detected in germinated cowpeas, but the vitamin was not detected in raw seeds. An increase on the antioxidant capacity (TEAC) in cowpea sprouts was also observed (58–67%). High pressure treatment (HP) slightly modified vitamin C content and TEAC and, after pressurization at 500 MPa, the decrease was more pronounced, although the germinated seeds submitted to this HP treatment still provided a high amount of vitamin C (15–17 mg/100 g d.m.) and the antioxidant capacity was 26–59% higher than that of the raw cowpeas. The HP process can provide minimally processed fresh-like sprouts of high quality.     

白肋烟种子萌发的生理生化动态研究

以TN86种子为材料,分析了白肋烟种子萌发特征及有关活性酶与相关物质的变化动态。结果表明,呼吸强度、淀粉酶与可溶性总糖和还原糖、蛋白酶与总游离氨基酸、脂肪酶与脂肪酸,以及过氧化物酶(POD)、多酚氧化酶(PPO)、可溶性蛋白质、脯氨酸(pro)、丙二醛(MDA)等的活性或含量都随萌发进程呈上升趋势,其间虽有所波动,但最高峰值期大都在第84-168h之间,仅POD与PPO活性和MDA含量在萌发中期才开始明显上升,直至萌发结束时达高峰值。淀粉酶、蛋白酶、脂肪酶活性与各自催化水解的产物含量呈极显著正相关;而粗脂肪含量随萌发进程而下降,与脂肪酸呈极显著负相关。萌发集中在48-72h,发芽势90%,同步指数0.92。萌发动态符合Logistic生长曲线方程。     

Changes in carbohydrate contents of germinating cowpea seeds

A decrease in the concentration of total carbohydrates was observed during 144 hours' germination of three cowpea varieties. However, whilst starch, raffinose, stachyose and verbascose levels decreased, the reducing sugars, including glucose and fructose, increased. Starch was the major carbohydrate and about 50% of it was hydrolysed after 144 hours' germination. Changes also occurred in the concentration of the unavailable carbohydrates. Lignin contents increased slightly while hemicelluloses and celluloses decreased. The above-mentioned changes, occurring during germination, appear to have a favourable effect on the nutritional value of cowpea varieties.     

Blood biochemical changes upon subclinical intramammary infection and inflammation in Holstein cattle

The aim of this study was to investigate the associations between subclinical intramammary infection (IMI) from different pathogens combined with inflammation status and a set of blood biochemical traits including energy-related metabolites, indicators of liver function or hepatic damage, oxidative stress, inflammation, innate immunity, and mineral status in 349 lactating Holstein cows. Data were analyzed with a linear model including the following fixed class effects: days in milk, parity, herd, somatic cell count (SCC), bacteriological status (positive and negative), and the SCC × bacteriological status interaction. Several metabolites had significant associations with subclinical IMI or SCC. Increased SCC was associated with a linear decrease in cholesterol concentrations which ranged from −2% for the class ≥50,000 and <200,000 cells/mL to −11% for the SCC class ≥400,000 cells/mL compared with the SCC class <50,000 cells/mL. A positive bacteriological result was associated with an increase in bilirubin (+24%), paraoxonase (+11%), the ratio paraoxonase/cholesterol (+9%), and advanced oxidation protein product concentration (+23%). Increased SCC were associated with a linear decrease in ferric reducing antioxidant power concentrations ranging from −3% for the class ≥50,000 and <200,000 cells/mL to −9% for the SCC class ≥400,000 cells/mL (respect to the SCC class <50,000 cells/mL). A positive bacteriological result was associated with an increase in haptoglobin concentrations (+19%). Increased SCC were also associated with a linear increase in haptoglobin concentrations, which ranged from +24% for the class ≥50,000 and <200,000 cells/mL (0.31 g/L) to +82% for the SCC class ≥400,000 cells/mL (0.45 g/L), with respect to the SCC class <50,000 cells/mL (0.25 g/L). Increased SCC were associated with a linear increase in ceruloplasmin concentrations (+15% for SCC ≥50,000 cells/mL). The observed changes in blood biochemical markers, mainly acute phase proteins and oxidative stress markers, suggest that cows with subclinical IMI may experience a systemic involvement.     

Seed coat tannins and bruchid resistance in stored cowpea seeds

Seeds of wild species and varieties of Vigna were screened for their tannins and α‐amylase inhibitor contents as defensive compounds against cowpea weevil. Seed coats contained condensed tannins that were positively correlated to their colour but not to their resistance against the insect. The α‐amylase inhibitors were present in different amount in cotyledons of all species analysed. Amongst the cultivated lines assayed, Vigna unguiculata TVu 2027, an accession identified as moderately resistant, was found to contain the higher amount of α‐amylase inhibitor. When wild species were considered, V luteola and V vexillata (two resistant species) showed the highest content of α‐amylase inhibitors. In addition, two cultivated accessions (Vita 7 and IT 84E‐1‐108) of cowpea seeds, both classified as susceptible accessions, showing a different degree of bruchid damage in storage, were also analysed. No α‐amylase inhibitory activity was found in cotyledons of undamaged Vita 7 seeds, while the seed coat tannin content was found to be 13 times higher in undamaged Vita 7 seeds than in IT 84E‐1‐108 infested seeds. These latter results support the hypothesis that seed coat tannins must also be considered in biochemical defence mechanisms, which can deter, poison or starve bruchid larvae that feed on cowpea seeds. Copyright © 2004 Society of Chemical Industry     

Metabolic changes of biochemical constituents in developing fennel seeds (Foeniculum vulgare)

Fennel (Foeniculum vulgare) is the major spice/condimental crop of Haryana, generally used in India for preparing pickles and in vegetable cooking. Flowers were tagged at anthesis, fennel seeds (local variety) were collected at 1-week intervals after 40 days from anthesis for studying biochemical constituents. Moisture and protein contents decreased significantly with the advancement of seed development. Oil content ranged from 68 to 135·7 g kg^?1 (dry weight basis), which increased with seed development. The oil content was greater in mature seeds. The presence of phytate (11·35–13·10 mg g^?1) was also observed, which affects the availability of Zn and Fe. Fennel seeds were found to be a rich source of micro- and macroelements. Neutral detergent fibre, acid detergent fibre, cellulose and lignin contents increased significantly with the advancement of seed development. Oleic and linoleic fatty acids were found to be major fatty acids and variable proportions of different fatty acids were observed.     

Establishing processing conditions for canning cowpea seeds in tomato sauce

The thermal process time and sensory attributes of Ife-BPC cowpeas canned in tomato sauce were studied. Heat resistance of Bacillus stearothermophilus 1518 was determined by the plate count method at 114.5 and 120.6°C. Surviving spores were cultured and TDT curves were plotted from these data to obtain D values of 2.2 ± 0.2 min at 120.6°C and 7.5 ± 0.5 min at 114.5°C. Heat penetration studies were conducted on two can sizes and at two operating temperatures. Thermal process parameters were determined using both the general and formula methods. There was no significant difference ( P < 0.05) in the process times determined by the two methods although slightly higher values were obtained with the formula method. The medium can size required a longer process time to approach the retort temperature than the small can size. The lethal effect of sterilizing at 120.6°C resulted in a lower D-value, higher sterilizing value (F₀), and higher safety ratio (a/b) than at 114.5°C. The final F₀ at the end of processing was greater than the targeted F₀ (11.0 min) from the 5D value, suggesting that the processing time is adequate for safe food production. Taste panel assessments were conducted to identify optimal processing conditions. The sensory attributes of dry and semi-dry Ife-BPC cowpeas canned in tomato sauce were compared with those of imported baked beans. Semi-dry processed cowpeas had high consumer preference over the dry seeds, and acceptable canning qualities similar to those of the imported baked beans.     

Modeling the thermal inactivation of phytase in steamed cowpea seeds

Cowpeas at moisture content of 20 g water/100 g were steamed at 100 or 121 °C for 0-900 s. Steamed seeds were milled whole or fractioned into three layers (inner, middle, outer) using a customized drill. Residual phytase activity was assayed by measuring the amount of inorganic phosphate produced using an external source of phytate. A combined kinetic and heat/mass transfer model was employed to predict phytase inactivation in the three layers. Seeds milled whole showed residual phytase activity between 59.5 and 63.4%, which was generally lower than the activity measured in the layers (60.3-81.4%) for the same treatment combination. Phytase was not uniformly inactivated throughout the seed but was spatially dependent. The measured residual activity in the outer layer (66%) was lower than in the middle (73%) and inner (75%) layers after 900 s steaming. The combined model predicted the spatial distribution of residual phytase activity at any given time. Predicted inactivation values were lower than experimental values. The average relative error for phytase inactivation was 5.8%, 12.3% and 14.2% respectively for outer, middle and inner layers. Predicted and measured residual activities were closer in the outer layer as compared to the inner and middle layers.     

Microstructural changes in hazelnuts during roasting

The microstructure of raw and roasted hazelnuts was investigated with light microscopy (LM). Tissue sections were fixed chemically using a mixture of formaldehyde, glutaraldehyde and buffer. Polyester was used as a resin. Thin sections were prepared by using a grinding method. Thermal changes in the microstructure developed gradually with increasing air temperature, air velocity and roasting time. Roasting led to some degree of cell wall separation and intercellular spaces, partial disruption of cytoplasmic network, swollen and aggregated protein bodies. These changes were observed in the microstructure of extremely liked quality of hazelnuts (roasted at 165 °C, 1 m/s, 25 min.). Due to the increase in the volume of intercellular spaces, crispness and crunchiness of roasted hazelnuts were increased.     

Effect of thermal and non-thermal processing on antioxidant potential of cowpea seeds

Legumes are a good source of bioactive components, besides being nutrient dense. These components have antioxidant properties and have a protective role against free radicals. Legumes like cowpeas are usually consumed after certain processing, so the present study was intended to assess antioxidant property of selected four cultivars of cowpea after going through various thermal (autoclaving, microwave, boiling, and roasting) and non-thermal (soaking and fermentation) processings. Thermal processing reduced total phenolic content (TPC), total flavonoid content (TFC), and ferric reducing antioxidant power (FRAP) in all cultivars with respect to antioxidant activity of raw cultivars, while DPPH scavenging activity increased after all thermal treatments excluding few thermal processings. Non-thermal processing revealed increase in TPC, DPPH scavenging activity, and FRAP values, while TFC content showed a decreasing trend. A moderately high correlation between TPC and DPPH scavenging activity was observed in both kinds of thermal treatments indicating the role of phenolic compounds for antioxidant activity. It was concluded from the study that fermentation processing has promising effects on retention and enhancement of antioxidant activity of cowpea cultivars.     

Phenolic compounds in germinated cereal and pulse seeds: Classification,transformation, and metabolic process

Abstract

Natural phenolic compounds are rich in cereal and pulse seeds and their dietary functions tend to improve dramatically during germination. This article reviews recent research on the transformation of phenolic compounds during seed germination. In particular, it highlights the classification of crude phenolic compounds that can be divided into extractable and non-extractable phenolic compounds based on the biosynthesis process and extraction method. It also recommends grouping resorcinol lipids in the category of extractable phenolic compounds as non-polar solvent extractable phenolic compounds. Moreover, it discusses the variation of the different form of phenolic compounds and proposes a possible metabolic model of these phenolic compounds for seeds germination. This article is crucial for phenolic compounds research, cereal and pulse seeds germination, and food ingredients industry.     

Primary and secondary metabolite compounds in cowpea seeds resistant to the cowpea bruchid [Callosobruchus maculatus (F.)] in postharvest storage

Cowpea is a one important legume crop in Sub-Saharan Africa due to its high content of protein and other nutrients. However, seeds of cowpea varieties are destroyed by Callosobruchus maculatus in storage. This study investigated various biochemical compounds of susceptible and resistant cowpea genotypes, to determine the biochemical compounds underlying cowpea resistance to bruchid. Six cowpea genotypes were analyzed in three replicates. One-way analysis of variance, Pearson correlation and path analysis were used to determine the influence of the biochemical compounds on the cowpea status. Amongst the cowpea genotypes assayed the biochemical compounds analyzed (Vicilin; α-amylase Inhibitor; Phenols; Condensed Tannin; Tannin; Carbohydrate; Flavonoid and Protein), were present in amounts. Resistant genotypes exhibited higher contents of Phenols (22.29 mg/g for WC66*5T and 19.74 mg/g for WC36); Tannin (2.45CEmg/g for WC36 and 2.52CEmg/g for TVU13677); and Carbohydrate (72.82% for TVU13677 and 71.09% for WC36). The most susceptible genotypes had the lowest content of Phenols (13.5 mg/g for TVU946 and 12.72 mg/g for Glessissaffodo); Tannin (0.74CEmg/g for Akounado and 0.97CEmg/g for Glessissaffodo) and Carbohydrate (60.95% for Akounado and 61.39% for TVU946), while Condensed Tannin was associated to their seed coat colour but not to their resistance status against bruchid. The resistant genotypes TVU13677; WC36 and WC66*5T were found to contain a higher amount of a subset of biochemical compounds as defensive compounds against cowpea bruchid. The susceptible cowpea genotypes (Akounado; Glessissaffodo; TVU946) screened for their biochemical content presented low amounts of these defensive compounds. The path analysis implemented highlighted the existence of causal relationships among biochemical compounds analyzed and resistance parameters, thus revealing the resistance basis of cowpea seed biochemical compounds. These latter results point out the possibilities to consider the presence of these biochemical compounds underlying the resistance of cowpea to bruchid in the breeding program toward the resistance to bruchid.     

Microstructural changes in strawberry after freezing and thawing processes

The selection of freezing conditions is very important in order to optimize the efficiency of the freezing process and simultaneously retain the biological microstructure. Fresh strawberry and osmotically dehydrated strawberry samples were frozen and thawed using several combinations of temperatures and air velocities. Different freezing and thawing rates were used, which resulted in varying degrees of mass transport from the intercellular to extracellular domain. Scanning electron microscopy (SEM) was used to visualize the degree of structural damages caused, which depended on the crystal size and water movement. SEM showed that better preservation of the structure was obtained using high freezing or thawing rates. When high temperatures were used for thawing, the tissue damage was greater and extensive. Pre-treatment with sucrose reduced the total mass of samples to about 2.5 g/100 g in the osmotically dehydrated samples but did not affect the tissue integrity. It is concluded that the freezing–thawing conditions are responsible for the modifications observed. By using this technique it was possible to establish relationships between the tissue structure and the processing conditions.     

Effect of combinations of high-pressure treatment and bacteriocin-producing lactic acid bacteria on the survival of Listeria monocytogenes in raw milk cheese

The combined effect of high-pressure (HP) treatment and bacteriocin-producing lactic acid bacteria (BP-LAB) on the survival of Listeria monocytogenes Scott A in cheeses made from raw milk that was inoculated with the pathogen at 4.80 log cfu mL⁻¹, a commercial starter and one of seven strains of BP-LAB was investigated. On day 3, the counts of L. monocytogenes were 7.03 log cfu g⁻¹ in a control cheese (without BP-LAB, not HP treated), 6.06–6.74 log cfu g⁻¹ in cheeses with BP-LAB, 6.13 log cfu g⁻¹ in a cheese without BP-LAB and treated on day 2 at 300 MPa, 2.01 log cfu g⁻¹ in a cheese without BP-LAB and treated on day 2 at 500 MPa, 3.83–5.43 log cfu g⁻¹ in cheeses with BP-LAB and treated on day 2 at 300 MPa, and 1.81 log cfu g⁻¹ or less in cheeses with BP-LAB and treated on day 2 at 500 MPa. HP treatment was more effective on day 51 than on day 2.