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1.
The variations in the total titratable acidity, hydrogen ion concentration, reducing sugar, soluble solids and alcohol contents of the supernatant of the submerged cashew pomace in a non-aseptic condition were investigated. The crude fibre content of the pomace was also determined during fermentation. At intervals, the changes in microbial load in both the pomace and its supernatant were examined during the 14-day study. Fifty four percent of the total soluble solids (TSS) was utilised within 7 days of degradation while an increase of about 91% in the total titratable acidity occurred in the cashew pomace within the same period bringing its pH to 3.24. Acid hydrolysis of the pomace accounted for the relative high value of 2.15% TSS on the 8th day. Isolates of the generaLeuconostoc, Lactobacillus, Pediococcus, Aspergillus, Rhizopus and some yeast strains were obtained from the fresh pomace. The fungal colonies constituted about 76% of the population in the cashew pomace. The 86% drop in microbial population of the 8th day biodegraded pomace could be attributed to a decrease in nutrients of the substrate and the inhibitory effect of the organic acids produced during fermentation.  相似文献   

2.
Natural as well as single, mixed and sequential pure cutlure (S. diastaticus, S. cerevisiae, L. brevis andL. fermentum) fermentations of pearl millet flour for 72h lowered pH and raised titratable acidity. The fermentation either decreased or did not change the protein content of pearl millet flour. Natural fermentation increased whereas pure culture fermentation decreased the fat content. Ash content did not change. Natural fermentation at 20°C and 25°C increased whereas at 30°C it decreased the thiamine content of the pearl millet flour. Yeast fermentation raised the level of thiamine two- to three-fold, while lactobacilli fermentation lowered it significantly.  相似文献   

3.
The composition and quality of edible tender stems or cladodes of 3 Prickly Pear Cactus species (Opuntia amyclaea, O. ficus-indica, and O. inermis) were studied at different stages of development. This traditional Mexican vegetable is called nopalitos in Spanish and cactus leaves in English. Cladodes harvested when 20 cm in length have the following average composition per 100 g: 91.7 g of water, 1.1 g of protein, 0.2 g of lipid, 1.3 g of ash, 1.1 g of crude fiber, 4.6 g of complex carbohydrates and 0.82 g of simple sugars, 12.7 mg of ascorbic acid and 28.9 µg of carotenes. The cladode's juice has an average pH of 4.6, 0.45% titratable acidity and 6.9% soluble solids. The components which varied most during development of the cladodes were: carotenes, acidity and total carbohydrates which increased, and protein and crude fiber (acid-detergent) which decreased. The nutritive value of the tender cladodes in the stages of growth at which they are commonly harvested and consumed (15 to 25 cm long weighing 50 to 80 g per stem), was similar for the 3 species.  相似文献   

4.
A good quality wine was produced from African bush mango (Irvingia var.gabonensis). Analysis of the African bush mango juice showed that it contained 3.6% total sugar, 1.09% protein, 4.2° Brix soluble solids (SS) 0.5% ash, 50.24% total solids (TS), 66.7 mg/100 ml ascorbic acid and pH 5.12. The juice ameliorated to 23° Brix was inoculated with 3% (w/v) Baker's yeast (Saccharomyces cerevisiae) and held at 30±2°C for 28 days. SS and pH decreased while titratable acidity (TA) increased with increasing period of fermentation. Fermentation was 110% efficient. The wine produced had 8.12% (v/v) alcohol, 0.78% protein, 6.5% Brix SS, 0.64 g/100 ml TA, and a pH 3.10. Sensory evaluation results showed that there was no significant difference (p=0.05) in colour, mouthfeel, sweetness, flavour and general acceptability, between African Bush mango wine and a reference wine. The wine was generally accepted.  相似文献   

5.
Field experiments were carried out at the Horticultural Research Institute, and in five commercial apple orchards, located in southwest Finland including the Åland Islands during 1994 and 1995. The experimental cultivars were Melba, Raike, Red Atlas, Åkerö, Aroma, and Lobo. The treatments were untreated control and preharvest calcium chloride (CaCl2) sprays at Ca 2.0 g/l. Fruit samples were stored for two to six months at 2–4 °C and 85–95% RH. The percentage of the incidence of physiological disorders of stored apples was scored. Fruit macronutrients, firmness, diameter and juice titratable acidity and percentage of soluble solids were determined. Only a few nutrient effects in the flesh of the apple cultivars were a result of CaCl2 sprayings. Preharvest CaCl2sprays increased fruit firmness and the titratable acidity but decreased soluble solids, soluble solids/titratable acidity ratio, and the incidence of physiological storage disorders of some cultivars. When looking at the mean of all cultivars, CaCl2 sprayings increased titratable acidity and decreased soluble solids/titratable acidity ratio after four months of storage during 1995 and reduced the incidence of physiological disorders after three months of storage during 1994 and after four months of storage in 1995.  相似文献   

6.
The pH, soluble nitrogen, soluble solids and titratable acidity increased during a 6 day fermentation of fluted pumpkin seeds. Gas liquid chromatographic analysis of trimethylsilyl (TMS) dirivatives of carbohydrates extracted from the seeds showed that the unfermented seeds contained mostly sucrose with a low content of flatus-oligosaccharides, raffinose and stachyose. There were also high contents of fructose and galactose. Fermentation increased the total monosaccharides with high content of glucose and some unidentified monosaccharides. Fermentation decreased the total oligosaccharide, eliminated raffinose and stachyose and increased the content of maltose. Except for a slight decrease in total saturated and increase in total unsaturated fatty acids, fermentation had no effect on fatty acid composition.  相似文献   

7.
Rice-defatted soy flour blends prepared in three proportions viz. 40:60, 50:50 and 60:40 were fermented with buttermilk at 25, 30 and 35°C for 12, 18 and 24h. Fermentation of these blends lowered the pH and raised the titratable acidity, maximum drop in pH and rise in titratable acidity being observed at 35°C for 24h. The fermentation either decreased or did not change the protein content of cereal-legume blends. Fat as well as ash content remained unaltered irrespective of temperature and time period of fermentation.  相似文献   

8.
Proximate composition and physicochemical analyses were carried out onthe seed, pulp and extracted oil of sour sop (Annona muricata). Theresults showed that the seed contained 8.5% moisture, 2.4% crudeprotein, 13.6% ash, 8.0% crude fiber, 20.5% fat and 47.0%carbohydrate. The seed also contained 0.2% water soluble ash, 0.79%titratable acidity and 17.0 mg calcium/100 g. The pulp was found tocontain 81% moisture, 3.43% titratable acidity and 24.5%non-reducing sugar. Selected physicochemical characteristics includedrefractive indices of 1.335 for the seed and 1.356 for the pulp, specificgravities of 1.250 for the seed and 1.023 for the pulp, pH values of 8.34for the seed and 4.56 for the pulp, and soluble solids contents of1.5 °Brix for the seed and 15 °Brix for the pulp. Theextracted oil (20.5% yield) had a 60.43% unsaponifiable value,23.54 KOH/g acid value, 100.98 K0H/g saponification value, 1.1 K0H/gperoxide value, 1.464 refractive index, 5.77 pH, 69.5 °Brix soslublesolids and 0.2900 specific gravity.  相似文献   

9.
Okpiye is a food condiment prepared by the fermentation ofProsopis africana seeds. The traditional process for the production and microbiological characteristics of the condiment were investigated. During laboratory fermentation that lasted 96h, the mesquite seeds underwent a natural fermentation that was characterised by the growth of microorganisms to 106–108 cfu/g. Several species of bacteria especiallyB. subtilis, B. licheniformis, B. megaterium, Staphylococcus epidermidis andMicrococcus spp were found to be the most actively involved organisms. However, significant contributions to the microbial ecology were made byEnterobacter cloacae andKlebsiella pneumoniae. Lactobacillus spp were present in low numbers towards the end of the fermentation. The presence ofProteus andPseudomonas spp in traditional fermented samples demonstrate the variability which may exist in the microflora of individual fermented samples. Variations in the important microbial groups show thatBacillus spp were the most prevalent species and occurred until the end of fermentation. Temperature, pH and titratable acidity varied with time and were influenced by the metabolic activities of the microorganisms.  相似文献   

10.
Biochemical and nutritional changes were studied during the ripening process of three Opuntia morphospecies with different ripening behavior: Naranjona (O. ficus-indica), Blanca Cristalina (Opuntia sp.), and Esmeralda (Opuntia sp.) of early, early-intermediate, and intermediate-late ripening, respectively. In loss of fresh weight, Naranjona showed the highest values, while in Blanca Cristalina and Esmeralda, a discrete weight loss was found. No significant differences were found among morphospecies in soluble solids, total titratable acidity and pH during the postharvest days. Blanca Cristalina and Esmeralda showed an increase in the content of carotenoids, while these diminished in Naranjona. The cell wall enzymes evaluated showed particular behaviors during the ripening of each morphospecies suggesting a fine biochemical control and not a clear relationship between fruit softening and enzyme activity. This study provides basic information on prickly pear ripening, in order to understand this process for its control and for improving shelf life.  相似文献   

11.
Rabadi fermentation of barley flour-buttermilk mixture (fresh and autoclaved) at 30, 35 and 40°C for 6, 12, 18, 24 and 48 h lowered pH, enhanced titratable acidity and did not change fat and total mineral (Ca, Fe, Cu, Zn, Mn and P) content. Protein content of fermented fresh as well as autoclaved barley flour-buttermilk mixture either decreased or remained unchanged.Rabadi prepared from both types of barley flour at different temperatures and time periods was acceptable; but that which was fermented at 40°C for 48 h was less acceptable in terms of taste.  相似文献   

12.
The effect of 40 h solid-state fermentation with Rhizopus oligosporus on selected parameters of white and coloured quinoa was studied, as compared to standard (30 h) product and cooked seeds.The reducing power (RP) and the activity against synthetic free radicals of standard tempe were higher by on average 140% (white) and 64% (coloured quinoa) than that of cooked seeds. The OH scavenging activity was increased by more than 7 fold (white), and over 2 fold (coloured quinoa). Prolongation of the fermentation caused further improvement in this potential, on average by 27% (OH, RP) and 24% (DPPH, ABTS+ assays). The soluble phenols i.e. vanillic acid, protocatechuic acid and rutin levels in 40 h tempe were significantly higher than in cooked quinoa. Fermented products contained 470% (white) and on average 150% (coloured quinoa) more riboflavin and 100% more thiamine (white quinoa) than cooked seeds. The levels of total protein, free amino acids and proteins releasable during the in vitro digestion, were improved as a result of 40 h fermentation. The essential amino acids profile of quinoa tempe was consistent with the reference pattern.The prolonged tempe-type fermentation of quinoa can be recommended as a method of the value-added food production.  相似文献   

13.
African locust-bean (Parkia filicoidea Welw) seeds were allowed to ferment under natural conditions and the chemical changes occurring during the fermentation were studied. Chemical analysis of fermented and unfermented beans showed a marked decrease in the total sugar content; crude and true protein levels all increased. The results of the chemical analyses indicate that fermentation resulted in protein enrichment of the fermented locust bean (daddaw). Fermentation also imparts a characteristic flavour and odour to the beans.  相似文献   

14.
A field experiment was carried out to study the effect ofcooking on protein solubility profiles of mycorrhizal inoculated, phosphorusand sulphur fertilized faba beans under two water regimes. The resultsindicated that cooking significantly (p 0.05) increasedthe G3-glutelin fraction as well as the insoluble protein butsignificantly (p 0.05) decreased the globulin and albuminfractions; prolamin, G1-glutelin and G2-glutelin fractionswere slightly increased. Mycorrhizal inoculation and mycorrhiza +phosphorus + sulphur fertilization significantly (p 0.05) increased albumin content. All fertilizer treatments significantly (p 0.05) decreased the insoluble protein.  相似文献   

15.
Fully riped cashew apples (yellow variety) were steamed for 7 minutes prior to juice extraction. The extracted juice was blended with various proportions of sweet orange juice. Chemical composition and organoleptic evaluation were carried out on both the blended and unblended juices. The ascorbic acid content of unsteamed cashew apple juice was 287 mg/100 ml. Steaming of the cashew apple prior to juice extraction resulted in a decreased (230 mg/100 ml) content of ascorbic acid. It also led to slight decreases in soluble solids and titratable acidity. A comparison of the chemical composition of the two juices showed that the orange juice contained more sugars, titratable acidity and soluble solids but less ascorbic acid than cashew apple juice. Consequently, the soluble solids, titratable acidity, reducing and total sugars of the blends increased with increase in the proportions of orange juice while the content of ascorbic acid was decreasing. In spite of the decrease in ascorbic acid content of the blends, results showed that blended juice would no doubt be a very good source of ascorbic acid. Result of the organoleptic evaluation revealed that a 60% cashew apple and 40% orange juice gave a good quality juice in terms of flavor, after taste and overall acceptability.  相似文献   

16.
Seeds of African locust bean, melon, castor oil bean and soybean were processed and fermented for 3 days to produce local condiments in the laboratory with a method that simulated the traditional production process. Microorganisms associated with their fermentation and the organoleptic properties of the products were compared.Altogether, seven species of bacteria were involved in the fermentation. These included fiveBacillus spp. and one species each ofPseudomonas andStaphylococcus. Their occurrence vary between the seeds on the different days of fermentation. However,Bacillus spp. were present in all the seeds throughout the fermentation period. The sensory evaluation preference rating for the four products was highest for soybean condiment, followed by that made from locust bean. Melon condiment was the least preferred among the four products. Statistical analysis showed that there were significant differences (P0.05) among the four products for each of the four organoleptic properties evaluated by the judges and also for titratable acidity. Glutamic acid level of soybean condiment was highest (0.31%) among the four products with that of melon being the lowest (0.04%). These results could serve as useful indices for the development of starter culture and optimization of production process in commercializing the production of these local condiments.  相似文献   

17.
Pepsin-treated protein bodies and human fecal protein particles from IR480-5-9 cooked milled rice (Oryza sativa L.) consisted mainly of giutelin-type polypeptides with a mean molecular weight (MW) of 16 000. They had similar MW, amino acid pattern, and isoelectric focusing characteristics as the 70% 2-propanol—0.6% -mercaptoethanol soluble fraction of rice glutelin. The lipids of the pepsin-treated protein bodies had an identical lipid fraction ratio and fatty acid composition as the lipids of whole protein bodies.  相似文献   

18.
本文以‘桂丰早’‘桂冠早’‘桂龙1号’‘古山2号’‘石硖’5个早熟品种(系)为材料,研究不同品种(品系)果实生长发育和品质变化规律。结果表明:在果实发育过程中,5个早熟龙眼品种(系)的横纵径、单果重、可食率、色差a*c*值均呈上升或波动上升;色差L*b*值呈快速上升后缓慢波动;可溶性固形物含量和大多数品种的维生素C呈先快速上升后缓慢下降;色差值和大多数品种的可滴定酸呈逐渐下降或波动下降;可溶性糖在成熟前是逐渐上升的,到后期则波动变化;可溶性蛋白呈“M”或“W”型波动;‘桂丰早’和‘桂冠早’比‘石硖’提前1周进入成熟期;‘桂龙1号’的退糖最慢;‘桂丰早’的横径、单果重及可溶性蛋白质含量最大,‘桂冠早’的纵径最大,‘桂龙1号’的可溶性固形物含量、维生素C和可溶性糖含量最高而可滴定酸含量最低,‘石硖’的可食率最高;综合评价成熟期的果实品质,则‘桂丰早’最佳,其次是‘石硖’,最后是‘桂龙1号’‘古山2号’和‘桂冠早’。  相似文献   

19.
African yam beans were fermented to obtain anowoh-type product. Microorganisms associatedwith the fermentation were Bacilluslicheniformis, B. pumilus, B. subtilis and Staphylococcus sp. Total microbial counts increasedfrom 1.53 × 105cfu/g to 1.51 × 109cfu/g under aerobic conditions, and from 8.0 × 103cfu/g to 1.35 × 107 cfu/g under conditions ofreduced oxygen tension. The pH of the substrateincreased throughout the fermentation, from 6.8 to7.5. A comparison of unfermented seeds with thefermented product showed that there were decreases inthe levels of total nitrogen, crude protein, crudefiber and lipids, and that there were increases in thelevels of carbohydrate and total organic matter.Enzyme activities during fermentation revealed thatamylase production was erratic showing a slightincrease during the first 24 h followed by a steeprise in activity in the next 24 h. By contrast, lipaseactivity increased rapidly throughout the first 72 hwhile proteinase activity followed a type of sigmoidcurve with a steady increase in activity within thefirst 48 h and a relatively high activity until the96th h before plunging downwards.  相似文献   

20.
本研究分析了龙眼干、枸杞和发芽糙米复合饮料采用酵母和醋杆菌进行连续发酵过程中其酒精度、pH、可滴 定酸、总糖、多糖、总酚和氨基酸态氮等品质指标的变化规律。结果表明,在酵母发酵期间,发酵 24 h 后复合饮料的 酒精度趋于稳定,残留的总糖为 1.40 g/L,多糖含量呈上升的趋势,总酚含量呈下降的趋势,氨基酸态氮总体上呈下降 的趋势。醋酸菌发酵期间,接种醋酸菌前热杀菌处理组和未热杀菌组的复合饮料中酒精度差别不大(p>0.05),未热杀 菌处理组在发酵期间复合饮料中可滴定酸含量、总糖含量、多糖含量和氨基酸态氮的含量均比热杀菌组的复合饮料中 的含量高,但热杀菌组的复合饮料中总酚含量总体大于未热杀菌组的复合饮料中的总酚含量。  相似文献   

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