Effect of cooking and sterilisation on the composition of amino acids in immature seeds of flageolet bean (Phaseolus vulgaris L.) cultivars

The aim of the work was to evaluate the amino acid content and protein quality in products of immature bean seeds with a dry matter content of 40%. The investigation included raw seeds, fresh seeds after cooking to consumption consistency and seeds after canning. Raw seeds of the cultivar Alamo contained more amino acids in 100 g fresh matter than the seeds of the cultivars Flaforte and Mona. Cooking and sterilisation brought about decreases in the content of all the amino acids in the investigated cultivars; 1–50% and 9–60% respectively. Higher losses being noted in sterilised seeds. If the results were expressed in 16 g N, the differences in amino acid content were much smaller. The amino acid content of Mona was lower than that of the remaining cultivars. The cooking of seeds did not bring about changes in relation to the raw material (except tyrosine which showed a decrease 35–45%); however, sterilisation affected the content of most amino acids (from −45 to +17%). Compared with the standard (FAO/WHO/UNU, 2007), the limiting amino acid was cystine with methionine (amino acid score 70–83). Of the seeds prepared for consumption, sterilised bean seeds had a higher EAA index value, while of the cultivars, the seeds of Alamo had the highest value (147–162).     

Culinary alternatives for common beans (Phaseolus vulgaris L.): sensory characteristics of immature seeds

BACKGROUND: Immature bean seeds feature in several dishes in southern Europe; however, they are not used in all traditional areas of dry beans cultivation. To determine whether differences in the use of immature seeds are due to cultural reasons or intrinsic properties of the seeds, the prestigious varieties of beans cultivated in three areas of Spain with different traditions regarding the use of immature seeds in bean dishes were studied. RESULTS: We found differences in the culinary and sensory traits between beans harvested when mature and those harvested when immature in the three areas. However, the degree and direction of these differences varied according to the area. Moreover, the different varieties tested within each area responded differently. The sum of the genetic, environmental and interaction effects results in complex alternatives to the mature beans; the gastronomic tradition has taken advantage of only some of these alternatives. CONCLUSIONS: A lack of traditional dishes using immature beans does not mean that the local beans harvested when immature lack suitable sensory traits. Specific trials in each area of cultivation can reveal alternative textures and bean flavour intensities in immature seeds. Copyright © 2010 Society of Chemical Industry     

冻结和冻藏对冷冻面团流变学以及汤包皮质构特性的影响

研究了冻结温度、冻藏温度、冻藏时间对冷冻面团流变学特性和汤包皮质构特性的影响。实验结果表明,冻结改变了面团的流变性质,降低了面团的弹性;并且-18℃下冻结对汤包皮TPA参数的影响比-30℃的影响大。-30℃的冻藏温度对面团的粘弹性影响较大,而不同冻藏温度对汤包皮的TPA参数影响不大;冻藏时间对面团粘弹性、面团拉伸特性以及汤包皮的TPA参数影响大。     

Evaluation of the amino acid content and sensory value of flageolet bean seeds (Phaseolus vulgaris L.) as affected by preprocessing methods before freezing

The aim of the work was to evaluate the content of amino acids in flageolet bean seeds, prepared for consumption from frozen products obtained using different methods. One of the frozen products was obtained using the traditional method (blanching–freezing–frozen storage) and then cooked. The other was obtained using the modified technology (cooking–freezing–frozen storage), followed by defrosting and heating in a microwave oven. The culinary and technological processing applied brought about a pronounced decrease in tyrosine content (35–47% in 16 g N). The content of the remaining amino acids decreased or increased in relation to the raw material within the extremes of ?15% to +17%. Sulphur amino acid was the limiting amino acid. Product obtained using traditional method had the higher quality protein (EAA index 144–166) of seeds prepared for consumption. In sensory test products, blanched before freezing were evaluated a bit higher than those cooked before freezing (ready‐to‐eat).     

Protein profile and antioxidant capacity of processed seeds from two common bean (Phaseolus vulgaris L.) cultivars

Common bean (Phaseolus vulgaris L.) seeds are an economical protein source rich in bioactive compounds with antioxidant activity. In this work, we evaluated processed seeds from two common bean cultivars regarding protein profile and antioxidant capacity before and after enzymatic digestion in vitro. We provided protein maps by two-dimensional electrophoresis (2-DE) of seeds germinated during 36 h and 72 h. The principal component analysis (PCA) showed that protein abundance had more variation on germination times than the cultivar ones. Seeds germinated for 36 h showed greater antioxidant capacity compared to germination for 72 h and cooking, before and after enzymatic digestion. In protein isolates, cooking associated with digestion provided better antioxidant capacity. Germination time influences protein expression as well as the antioxidant capacity of common beans. Furthermore, in vitro digestion increases the antioxidant capacity of cooked bean protein isolates.     

Processing,suitability and nutritive value of field bean seeds after germination

An attempt was made to obtain hydrolysates from field bean seeds after germination. The activity of native proteolytic enzymes, ascorbic acid and phytate phosphorus contents, as well as the activity of proteolytic enzyme inhibitors were studied, as influenced by seed steeping, water acidity and aerating conditions. Germinated field bean seeds were found to be suitable for hydrolysate production. The enzyme activity, as well as the contents of compounds responsible for the nutritive value of seed was determined and depended on germinating conditions.     

Content of amino acids in fresh and frozen and cooked broad bean seeds (Vicia faba var major) depending on cultivar and degree of maturity

In broad been seeds (cultivars Comprimo RS and Threefoldwhite) harvested at four stages of maturity, which corresponded to dry matter content at the levels of I—25%, II—30%, III—35% and IV—40%, the content of amino acids was determined (g 16 g N⁻¹). The determinations concerned raw broad bean and frozen products cooked for consumption. The content of total and essential amino acids was similar in the two cultivars. With increasing maturity the content of total amino acids and essential amino acids varied, showing a tendency to increase between maturity stages I and IV in all the amino acids, except aspartic acid and alanine in Threefoldwhite. In both cultivars the content of cystine and glutamic acid showed the most rapid rise. Compared with raw broad beans, intact seeds cooked for consumption contained more total amino acids. In products of Comprimo RS the total content of amino acids and essential amino acids was similar in intact seeds and in the dehulled seeds. In products from Threefoldwhite the content of total amino acids and essential amino acids was higher in intact seeds than in dehulled seeds except in the most mature sample where these values were similar. The limiting amino acids were methionine with cystine in both raw broad bean and cooked seeds. © 1999 Society of Chemical Industry     

Effect of freezing/thawing conditions and long‐term frozen storage on the quality of mashed potatoes

The effects of freezing temperature (−80, −40 or −24 °C) and thawing mode (microwave or overnight at 4 °C) on quality parameters of mashed potatoes made from tubers (cv Kennebec) and from potato flakes were examined, as was the effect of long‐term frozen storage on the quality of mashed potatoes. Mashed potatoes were tested for texture profile analysis (TPA) and cone penetration, oscillatory and steady rheometry, colour, dry matter, Brix and sensory analyses. In natural mashed potatoes, TPA hardness and oscillatory parameters showed that processing resulted in a softer product than the fresh control. The parameters were lower in the samples thawed at 4 °C than in those thawed by microwave at all the freezing temperatures used, which may be ascribed to gelatinisation of the starch released from damaged cells. Differences from the freshly prepared product decreased when the samples were frozen at −80 °C and thawed by microwave. No difference was found in sensory acceptability between samples frozen at −80 and −40 °C, which probably reflects the panellists' mixed preferences for air‐thawed versus microwave‐thawed samples. Increasing the time in frozen storage led to a natural mash with a firmer texture, higher L*/b* value and Brix; nonetheless, panellists found the samples at 0, 3 and 12 months of frozen storage equally acceptable. In commercial mash, penetration and oscillatory parameters showed that processing made for a firmer product than the fresh control, probably owing to retrogradation of gelatinised starch. Thawing mode had a significant effect on parameters, which were lower in the samples thawed at 4 °C. The structure and quality of commercial mash was more detrimentally affected by freezing and, therefore, we would not recommend either freezing or frozen storage of this mashed potato in the used conditions. Natural mash made from Kennebec potatoes should be frozen quickly and thawed by microwave in the conditions described to obtain a product more similar to that freshly made. If the samples are frozen by air blasting at −40 °C, the product can withstand frozen storage for one year. Copyright © 2005 Society of Chemical Industry     

Purification and properties of polyphenol oxidase from oil bean (Pentaclethra macrophylla Benth) seeds

Polyphenol oxidase extracted from oil bean (Pentaclethra macrophylla) seeds was purified 165-fold over the crude enzyme extract. The apparent molecular weight of the enzyme by gel filtration was 110.8 k ± 9.0 k while SDS-PAGE indicated a single species of molecular weight 28.0 k. A copper content of 1.9 mg g^?1 corresponds to one copper atom for each of the four subunits. The purified enzyme oxidised pyrogallol, catechol, 4-methylcatechol and L-dihydroxyphenylalanine but had low activity towards tyrosine. p-Cresol, caffeic acid and cholorogenic acid were not oxidised. Thio-compounds were strong inhibitors of the enzyme. The phenolic compounds tyrosine, resorcinol and orcinol inhibited catechol oxidation but became oxidised in the process.     

Changes in the radical-scavenging activity of bitter gourd (Momordica charantia L.) during freezing and frozen storage with or without blanching

The effects of blanching, freezing, and frozen storage on the retention of radical-scavenging activity (RSA), total phenolics, and ascorbic acid in bitter gourd were investigated. Blanching of sliced bitter gourd resulted in considerable losses of RSA and total phenolics, and most extensively, of ascorbic acid. In the subsequent frozen storage at -18 degrees C, RSA and total phenolic content of unblanched and blanched bitter gourd underwent little change for 90 d then gradually declined, but at -40 degrees C, they practically remained unchanged throughout the entire storage period. On the contrary, ascorbic acid content of both unblanched and blanched bitter gourd decreased abruptly at the early stage in frozen storage. The results show that blanching of bitter gourd improves the retention of RSA and total phenolics during subsequent frozen storage but markedly aggravated loss of ascorbic acid. Finally, it is to be noted that RSA, total phenolics, and ascorbic acid originally contained in the raw bitter gourd were overall best retained by quick freezing followed by frozen storage at -40 degrees C without preceding blanching.     

Antioxidant and antimutagenic activity of phenolic compounds in three different colour groups of common bean cultivars (Phaseolus vulgaris)

Total phenolic content of seven improved common bean cultivars (Phaseolus vulgaris L.) namely, Negro Altiplano, Negro Durango, Negro Sahuatoba, Flor de mayo sol, Flor de Mayo Bajío, Flor de Mayo 94044MX and Bayo Madero were analyzed. Acetone and methanol extracts from bean cotyledons were obtained by successive extractions. Total phenolic content was evaluated following Folin–Ciocalteu method; antioxidant activity by the DPPH technique; antimutagenic potential by the Ames method; and preliminary identification was realized by 2D-TLC. Results indicated high correlation between total phenol content and antioxidant activity for acetone extracts, and also high correlation between antioxidant and antimutagenic activities. In contrast, low correlation coefficients were obtained for methanol extracts. Three cultivars (two Negro cultivars and a Flor de Mayo type) showed lower antimutagenic activity than catechin.     

Total and soluble oxalate content in legume vegetables used in the preparation of frozen products for consumption

The aim of the investigation was to compare oxalate retention in two types of frozen product prepared for consumption after frozen storage: one obtained using the traditional method (blanching‐freezing‐frozen storage‐cooking) and a convenience food involving cooking‐freezing‐frozen storage‐defrosting and heating in microwave oven. The investigation included three species of legume vegetables: immature (wax‐stage maturity) seeds of broad bean and green pea, and French bean. Fresh broad bean seeds contained 53 mg total oxalates in 100 g fresh matter; pea 38 mg; and French bean 88 mg. Soluble oxalates comprised 53, 58 and 72% of total oxalates. The treatments applied resulted in reduction of the level of total and soluble oxalates, and oxalate to calcium ratio (broad bean and French bean); there was no influence on the level of calcium bound as calcium oxalate; true retention of oxalates was lower than apparent retention (green pea and French bean).     

Quality changes of pork during frozen storage: comparison of immersion solution freezing and air blast freezing

This study evaluated the effects of freezing method and storage time on the quality changes of pork longissimus thoracis (LT). The results showed that, compared to air blast freezing (AF), better microstructure was observed in pork under immersion solution freezing (ISF) mainly due to higher freezing rate. ISF group had significantly lower thawing loss at 1, 31 and 91 days and higher shear force at 1 day than AF (P < 0.05). A significant reduction in TBARS value at 61 and 91 days was observed in ISF samples (P < 0.05). No significant differences were observed between the two treatments in the colour, cooking loss and sulfhydryl groups (P > 0.05). All quality indicators were significantly affected by storage time (P < 0.05). It is concluded that ISF could maintain better microstructure, improve water-holding capacity and inhibit lipid oxidation during pork LT frozen storage.     

不同滞留时间与滞留温度对未冻及冷冻鳙鱼品质变化的影响

以鳙鱼鱼块为研究对象,探讨了冷冻前滞留温度(4、20℃)及滞留时间(1~24 h、1~8 h)对鱼肉p H、感官评分、挥发性盐基氮、剪切力、解冻汁液流失率以及鱼肉显微结构的影响。结果表明:鳙鱼宰后p H变化在8 h(4℃)和4 h(20℃)出现转折,p H在转折点以前下降较快,在转折点以后下降缓慢或轻微上升;感官评分随冻前滞留时间延长出现先慢后快的降低趋势,挥发性盐基氮随时间延长增长先慢后快,转折点均出现在8 h(4℃)和4 h(20℃)。肌纤维间空隙随滞留时间延长增大,纤维排列紊乱。冷冻鳙鱼的解冻汁液流失率随滞留时间延长逐渐增加,p H、感官评分、挥发性盐基氮、剪切力变化趋势与未冻结鱼肉一致,肌纤维排列更加疏松。鳙鱼宰杀后在4℃和20℃下滞留时间分别不超过8 h和4 h,冷冻后鱼肉的品质较好。      

液氮冻结温度对冻藏黄鳝脂质氧化和气味变化的影响

目的 探讨液氮冻结温度对冻藏黄鳝脂质氧化和气味变化的影响。方法 测定液氮冻结(?50、?80、?110℃)和?20℃冰柜冻结(对照)的冻藏黄鳝的脂质和游离脂肪酸(free fatty acids, FFAs)含量、过氧化值(peroxide value, POV)、硫代巴比妥酸反应物(thiobarbituric acid reactive substances, TBARs)、脂肪酸组成、挥发性气味物质, 并进行感官评价。结果 随着冻藏时间的延长, 整体上4种温度条件下黄鳝的脂质、单不饱和脂肪酸(monounsaturated fatty acids, MUFAs)和多不饱和脂肪酸(polyunsaturated fatty acids, PUFAs)含量显著下降(P<0.05), FFAs、POV、TBARs值及饱和脂肪酸(saturated fatty acids, SFAs)含量显著上升(P<0.05)。液氮冻结黄鳝的脂质、MUFAs、PUFAs含量和感官评分高于对照, ?80℃和?110℃液氮冻结黄鳝的FFAs、SFAs含量显著低于?50℃液氮冻结和对照(P<0.05); ?80℃和?110℃液氮冻结黄鳝的脂质氧化差异基本上不显著(P>0.05)。气相色谱-离子迁移谱法检测出25种挥发性气味物质。此外, 液氮冻结温度越低, 冻藏黄鳝的正己醛和正丙醛相对含量越低。结论 降低液氮冻结温度能够显著抑制冻藏黄鳝的脂质氧化和气味变化, 有效保护黄鳝的品质。     

Variation in protein and trypsin inhibitor activity with maturity and amino acid composition of winged bean (Psophocarpus tetragonolobus) seeds

The protein and trypsin inhibitor activity in pods and seeds of winged bean (Psophocarpus tetragonolobus (L) DC) increase, and in the pod hull decrease, with the maturity of plant. The seeds of 21 cultivars both exotic and of Indian origin cultivated on marginal alkaline soil (pH 8.7) were analysed for protein (36.4–45.3) and amino acid composition (lysine 4.8 to 6.7).     

Effect of drought on polyamine metabolism,yield, protein content and in vitro protein digestibility in tepary (Phaseolus acutifolius) and common (Phaseolus vulgaris) bean seeds

The objective of the present study was to investigate the effect of drought on the metabolism of proline, ornithine and polyamines, and the enzymes involved in their synthesis and degradation, in tepary and common bean seeds. Furthermore, the effect on seed yield, protein content and in vitro protein digestibility was also studied. Genotypes of tepary bean (Phaseolus acutifolius) used were: PI‐301‐801 from Nicaragua; G‐400‐35 from Oaxaca, Mexico; L‐242‐24 and L‐242‐36 from Sonora, Mexico; L‐172 from Arizona, USA; and the common bean (Phaseolus vulgaris) variety Flor de Mayo Bajío (FMB) from Mexico. The cultivars were grown in a greenhouse under controlled temperature, light and humidity. Water content in plants (WCP) decreased when irrigation was stopped (1 and 2 weeks after blooming). Common bean had the lowest WCP value (73.75%), while the best genotypes were PI‐301‐801 (91.62%), G‐400‐35 (88.70%) and L‐242‐24 (85.73%). Tepary bean plants had superior water absorption capacity, which helped to increase yield. De novo synthesis of drought proteins may explain the increased protein content present under drought conditions. The results suggest that water stress induced ornithine amino transferase activity and ornithine concentration. Proline also increased under drought conditions (p < 0.05). Genotypes L‐242‐24 and G‐400‐35, which had the highest yield, also had a major concentration of polyamines under water stress. The results also suggest that arginase activity participated in amino acid synthesis such as ornithine and, consequently, in the protein concentration under water stress. Genotypes G‐400‐35 and L‐242‐24 are good alternatives for cultivation in arid zones. Copyright © 2003 Society of Chemical Industry