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In the Base Business Unit (UEB) La Española I, cured meat is made. In the refrigerated storage stage of the final product, the presence of exudate was observed in the vacuumsealed blankets. To reduce it, it is proposed to incorporate the baking operation into the process. Objective: To incorporate baking as an operation to reduce the amount of exudate present in the final product once vacuum sealed. Materials and Methods: Two experimental variants were analysed, one of them, the traditional one, where after the dry curing process it is passed to vacuum packaging and in the other the baking is introduced before the final packaging. The characterization of the final product was carried out from the physical, chemical, microbiological and sensory point of view. Different measurements were made before and after the baking process; as well as on the mass of exudate present in the packaged product. Results and Discussion: The baking process decreases the yield of the product and therefore increases the consumption rates of raw materials, which influences the cost of production. The product obtained in each variant complies with the regulated parameters. The baking process was able to reduce the amount of exudate present in the final product. Conclusions: The two variants studied were able to reduce the amount of exudate present in cured beef jerky type after vacuum packaging. The baking process increases the cost of production and decreases the yield of the product. [ABSTRACT FROM AUTHOR]

Introduction: Currently, the specie that is cultivated in Cuba is the Pacific white shrimp (Litopenaeus vannamei), due to its rapid reproduction and food conversion and is mainly used for export. In its processing, large amounts of waste are generated that can be used for obtaining products of commercial value, thereby reducing the environmental impact of this industry. Objective: To evaluate the deacetylation stage of chitin obtained experimentally from the Litopenaeus vannamei shrimp exoskeleton by chemical means. Materials and Methods: The chitin was obtained from the Litopenaeus vannamei shrimp exoskeleton, it was deacetylated with a NaOH solution at 10 mol/L, in a solid-liquid ratio 1: 4 (p / v), at 80 °C, 250 min-1, for two hours. The degrees of acetylation (DA) and deacetylation (DD) were calculated according to Khan et al., (2002). The test of the solubility of chitosan was also carried out according to Barra et al., (2012). The infrared spectra of chitin and chitosan were determined with FTIR equipment with ATR attachment. Results and Discussion: The degree of deacetylation for chitin was similar to that for chitosan, due to the effect of insufficient deproteinization of chitin. This was corroborated by the chitosan solubility test which showed a low quality. The IR spectra of chitin and chitosan were similar. Conclusions: The deproteinization of chitin influenced in the quality, and therefore, in its deacetylation. It must be guaranteed to work at temperatures close to 100 °C to achieve a good quality chitosan. [ABSTRACT FROM AUTHOR]

The scarce oil supplies and the emissions of gases of greenhouse effect have caused the interest in production and utilization of lignocellulosic bioethanol. This can substitute partially or totally the fossil fuels. The stages of pretreatment and enzymatic hydrolysis are the most expensive. Different pretreatments have been studied for ethanol production from these materials. Their results depend on the method characteristics and on biomass used. The agroindustrial wastes present a composition with possibilities of being evaluated like raw material for bioethanol production. In the present research, the pretreatment stages with Ultrasound and Ozone are studied, in order to decrease the lignin content and to increase the performance of the fermentative sugars in the lignocellulosic wastes (rice hull and dark tobacco vein). In the first pretreatment procedure, time and waste type were studied and in the second stage, the ozone concentration, waste type and moisture content were the studied variables. A combined procedure was applied to the best preliminary results. It is demonstrated that a decrease in the lignin concentration and the structural transformation of the materials under consideration come true. The best results were gotten for the rice hulls. [ABSTRACT FROM AUTHOR]

The normal process of obtaining chitin from the shrimp exoskeleton consists in associated compounds extraction through successive steps of demineralization, deproteinization and depigmentation, using strong acids and alkalis. It constitutes a risk for personal and environmental integrity. A solution to this problem is the alternative methods use, such as enzymatic extraction, which in addition to maintain the structure of chitin intact, do not produce wastes that may affect their biomedical applications. The exoskeleton, once clean, dry and ground to 300 μm, is demineralized, up to 95,67% using glacial acetic acid at 15% at room temperature and stirring for 3 hours. A treatment with α-chymotrypsin in an enzyme-substrate ratio E / S 0,7: 100 (QB2) shows a higher percentage of protein hydrolysis, 73,48% than the E / S ratio 0,5: 100 (QB1) . However, it was found that there is not statistically significant difference between the different treatments, only a difference between the QB1 and QB2 treatments was observed, which seems to indicate which seems to indicate that a greater deproteinization of the substrate occurs at a higher concentration of chymotrypsin.On the other hand, papain treatments reached similar percentages of deproteinization, 65,43% and 67,13% for E/S ratios of 0,5: 100 and 0,7: 100 respectively, which indicates that both treatments are statistically acceptable. Regarding the degree of deacetylation, all the treatments showed a value of approximately 20% and a molecular mass of the order of 106, thus demonstrating the effectiveness of the combination of treatments with weak acids and proteolytic enzymes. [ABSTRACT FROM AUTHOR]

The processing of Aloe vera (sábila in sp.) has reached a great development during the last years, since its products are raw material for other industries. This has contributed to the increase of solid residues, which are not utilized to obtain added value products in the same industry. In this research, the acid hydrolysis method for pectin extraction from the Aloe vera bagasse was studied. Firstly, the bagasse was characterized determinig: humidity, ashes, proteins, acidity, and total content of pectin, density and pH. pH, temperature, extraction time, particle size and speed of agitation were analyzed as variables of study or factors and pectin yield (%) as response variable. The best results were obtained at 90°C, 1000 min-1 and the larger particle size that were the significant variables with 95 % of confidence. Pectin was characterized chemically and for infrared spectroscopy (FTIR). It was concluded that this pectin was of fast gellification variety, water-soluble and of high methoxyl content. The characteristic peaks of the functional groups of pectin were observed in infrared spectroscopy (FTIR) analysis. [ABSTRACT FROM AUTHOR]

The availability of fermentable sugars is a limiting factor for large-scale production of biological products such as bioethanol. Therefore, processes to produce sugars are being developed from lignocellulosic materials by enzymatic hydrolysis. However, the cellulose fraction are not readily accessible for the hydrolyzing enzymes and an efficient hydrolysis requires pretreatment. Several processes have been investigated for this pretreatment. Pretreatment of lignocelluloses with NaOH is among the promissing methods. In the present work, the effect of NaOH pretreatment at low temperature on chemical composition and subsequent enzymatic hydrolysis of spruce was investigated. A native spruce specie obtained from the forest around Borås city in Sweden was used in an the experiments. This wood was analyzed for carbohydrate and lignin fractions according to NREL methods. The wood was chemically pretreated using 7 % (w/w) sodium hydroxide solution with 5 % (w/v) solid content at 0 °C for 0.5, 1, 2 and 3 h. Commercial enzymes, cellulase (Celluclast 1.5 L, Novozyme, Denmark) and β-glucosidase (Novozyme 188, Novozyme, Denmark) were used in the enzymatic hydrolysis with activities of 30 FPU and 50 IU per gram of wood, respectively. The pretreatments changed the material composition. It was a very low loss of carbohydrate, about 98 % recovery, suggesting no significant carbohydrate hydrolysis. Xylans were the most affected by the pretreatments. The largest xylan removal was almost 50 %, using sodium hydroxide solution for 3 h. The profile of released sugars were also analyzed and compared. An improvement of enzymatic hydrolysis yield was observed as a result of the applied pretreatments, near 40 % glucose yield could be achieved. [ABSTRACT FROM AUTHOR]

Introduction: Moringa oleifera is a plant with nutritional and antioxidant properties that contribute to well-being and diseases prevention. Bakery products are considered a mass consumption and even dietary food. Their acceptance is given by its easiness of transport and its long conservation periods. Objective: To evaluate the nutritional contribution of the cookies and cakes elaborated with moringa dry pods flour and their quality after 30 days of its elaboration. Materials and Methods: Cookies and cakes were elaborated by traditional method with compound flour (30 % moringa and 70 % wheat) that obtained the biggest acceptance. both products chemicalphysic properties and nutritional parameters were determined according the COVENIN norms. The useful life time was determined during four weeks. Results and Discussion: Both products, cookies and cakes elaborated with moringa dry pods flour, presented a superior content of proteins that the established for the norm. In cookies the humidity was inferior to the one required and it didn't allow microbial contamination, not happening the same for the cakes. The quality of the cookies and cakes stayed respectively until 30 and 15 days. Conclusions: Partial substitution of moringa dry pods flour in cookies and cakes elaboration increases its nutritional value, maintaining its quality respectively during 30 and 15 days. [ABSTRACT FROM AUTHOR]