Blanching Process Research Articles

Study of Microbiological Quality and Antioxidant Activity Beras Kencur Drink with Heating Process

Beras kencur drink is well known as Indonesian herbal drink made from kencur (Kaempferia galanga L.) mixed with other functional ingredients through minimally-processing. The aim of this research was to evaluate microbiological quality and determine antioxidant activity of beras kencur drink with blanching and pasteurization treatment. Five samples were subjected to microbiological analysis by total plate count (TPC). Furthermore, the variation of heat treatment is blanching (5 and 10 minutes) and pasteurization. The sample were evaluated for pH value, total dissolved solids, total microbial, antioxidant activity, total phenolic content, total flavonoid content, and ferric reducing power. The results showed that five samples of beras kencur drink had varied total microbial amount while the samples treated with blanching and pasteurization had lower total microbial number. Samples with blanching kencur 5 minutes, blanching kencur 10 minutes and pasteurization had antioxidant activity of 80,30 %RSA, 64,78 %RSA and 58,24 %RSA, respectively, total phenolic content 1747,17 mgGAE/L, 1610 mgGAE/L, and 1465,13 mgGAE/L, respectively, total flavonoid content of 169,49 mgEK/L, 160,36 mgEK/L, and 136,31 mgEK/L, and ferric reducing power -1186,92 mgAA/L, 960,50 mgAA/L, and 897,61 mgAA/L. Beras kencur drink with blanching and pasteurization process had lower total microbial number and can improve antioxidant activity.

Blanching effect on the bioactive compounds and on the viability of Lactobacillus rhamnosus GG before and after in vitro simulation of the digestive system in jabuticaba juice

The viability of Lactobacillus rhamnosus GG (LGG) in jabuticaba juices and its survival in the gastrointestinal tract (GIT), simulated in vitro, was studied. Two juices were prepared: A - with non-blanched fruits, and B - with blanched fruits. LGG was then added and the juices maintained at 8 ºC for 28 days. The control treatment consisted of juices without the added probiotic. The following were determined in the juices: the viability and in vitro survival of LGG, fecal coliforms, Salmonella sp., pH, acidity, total soluble solids (TSS), color, antioxidant capacity, total phenolic compounds, anthocyanins and ascorbic acid. The sensory acceptability was also determined using a 9-point hedonic scale. Blanching interfered (p < 0.05) with the viability of LGG, juice A showing the greatest viability as compared to juice B. After in vitro simulation, the probiotic bacterial count was < 1.0 log CFU mL-1, which demonstrates the low resistance of the strain to the simulated GIT conditions. The juices were conformed to the microbiological standards established by law. The pH, acidity and TSS were influenced by blanching (p < 0.05), with values of 5.03, 0.46% and 15.38 °Brix for juice A and 5.12, 0.66% and 16.05 °Brix for juice B, respectively. The addition of LGG did not influence these characteristics. Only the pH value was influenced by the storage time (p < 0.05), increasing throughout storage. Juice B showed lower luminosity (L*) and a greater value for a* as compared to juice A, indicating that the former became darker and redder due to the blanching process. Both juices showed positive values for the b* coordinate. The juice was found to be a good source of polyphenols. Neither the time nor the addition of LGG affected the antioxidant capacity, total phenolic compounds or anthocyanin contents. However, blanching contributed (p < 0.05) to an increase in the contents of these compounds in the juices. Values for antioxidant capacity of 186.20 and 2552.59 uM Trolox g-1, for total phenolic compounds of 275.06 and 1163.18 mg GAE 100 g-1-wwb, and for anthocyanins as cyanidin 3-glucoside of 12.71 and 90.99 mg 100 g-1 were found for juices A and B, respectively. The juices contained 72.87 mg 100 mL-1 of ascorbic acid. Scores of above 6.0 (liked slightly) were awarded on the hedonic scale for the attributes evaluated. The addition of probiotics in jabuticaba juices needs to be further studied to ensure the viability of the cultures during storage and their survival in the gastrointestinal tract.

Underwater shockwave pretreatment process for improving carotenoid content and yield of extracted carrot (Daucus carota L.) juice

Carrots (Daucus carota L.) are an important source of antioxidants with both lipophilic (carotenoids, xanthophylls) and hydrophilic (polyphenols) properties. In this study, we evaluate the yield and carotenoid content of the juice obtained upon subjecting carrots to an underwater shockwave pretreatment. There is a significant increase in the juice yield and a two-fold increase in the α- and β-carotene contents compared to that of raw carrot juice when a shockwave pretreatment of 5 cycles at 3.5 kV and 4.9 kJ is employed. The sugar concentration (°Bx) of the shockwave-treated carrot juice increases by 15.5% without a blanching process. The treatment method proposed here is a reliable and efficient technique for the extraction of functional antioxidant chemicals from carrots. This study demonstrates the broad applicability of the underwater shockwave technique for improving the carotenoid content in carrot juice, confirming its potential for application in a wide range of food extraction processes.

Impact of processing on odour-active compounds of a mixed tomato-onion puree.

Gas chromatography-olfactometry revealed thirty-two odour-active compounds in a heat-processed tomato-onion puree, among which twenty-seven were identified by gas chromatography-olfactometry-mass spectrometry (GC-O-MS) and comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOF MS). Based on the results of two olfactometric methods, i.e. detection frequency and aroma extract dilution analysis, the most potent aroma components include: dipropyl disulfide, S-propyl thioacetate, dimethyl trisulfide, 1-octen-3-one, methional, dipropyl trisulfide, 4,5-dimethylthiazole, 2-phenylacetaldehyde and sotolone. Processing of mixed vegetable systems can add complexity in their aroma profiles due to (bio)chemical interactions between the components. Therefore, the impact of different processing steps (i.e. thermal blanching, all-in-one and split-stream processes) on the volatile profile and aroma of a mixed tomato-onion puree has been investigated using a GC-MS fingerprinting approach. Results showed the potential to control the aroma in a mixed tomato-onion system through process-induced enzymatic modulations for producing tomato-onion food products with distinct aroma characteristics.

Influence of hot water blanching process on phenolic profile and antioxidant activity of Cinnamomum porrectum herbal tea

Background: C. porrectum leaves, one kind of Cinnamomum family, has recently been used to produce a locally herbal tea. Although C. porrectum essential oil and aqueous extract have been reported to have some biological activities, including antioxidant, antimicrobial, and anti-inflammatory activities, there is no scientific data using the blanching process for the production of herbal tea. Therefore, this experiment aimed to study the effect of hot water blanching before drying process on microstructure, nutrition content of the tea powder, TPC, TFC, antioxidant activities of infusion, as well as the phenolic profile of the extract.Objective: To determine effect of hot water blanching process on nutritional value, microstructure, phenolic profile, and antioxidant activity of the C. porrectum herbal tea.Methods: The C. porrectum leaves were divided into 2 groups; control (un-treated) and blanched before dried for herbal tea processing. The fresh leaves and the powders of control and blanched leaves were checked for proximate composition and chlorophyll contents, in addition to color value. The powders were determined microstructure by SEM. The infusions were determined to have color value and total extractable phenolic and flavonoid contents, as well as antioxidant activities. The hydrolyzed extracts of freeze dried infusion were subjected to identify phenolic profile by HPLC. Results: The blanched tea powder yielded a percentage of fat and protein contents higher than un-treated due to easier extraction because of the bigger pore size found in microstructure. Chlorophyll content of blanched was decreased compared with the control sample. However, it was found that blanching could greater maintain green color of both powder and infusion. Additionally, blanching helped increased TPC, TFC extractability, and antioxidant activities in all assays except metal chelating property. Based on retention time and peak profile determined by using HPLC, it was found that both control and treated extracts consisted of similar main phenolic and flavonoid compounds however, only kaempferol was found in un-treated. Moreover, hydrolyzed blanched extract showed a higher intensity of 2 unknown compounds than un-treated. Though un-treated provided a higher intensity of pyrogallol, gallic acid, and cinnamic acid, the blanched exhibited a higher intensity of caffeic acid, protocatechuic acid, p-coumaric acid, and rutin. Conclusion: Blanching before drying expanded pore size of dried leaves, increased yield extractability, maintained color value, chlorophylls and increased TPC and TFC which related to antioxidant activities. Blanched extract provided higher intensity of some phenolic compounds than un-treated.Keywords: Cinnamomum porrectum, blanching process, SEM, HPLC

Enhancing the lycopene in vitro bioaccessibility of tomato juice synergistically applying thermal and non-thermal processing technologies.

The influence of moderate intensity pulsed electric field pre-processing on increasing the lycopene bioaccessibility of tomato fruit, and the combined effect of blanching, ultrasonic and high intensity pulsed electric field processing on further enhancement of the lycopene bioaccessibility after juicing were investigated. Maximum total lycopene bioaccessibility (9.6%) of the tomato fruit was achieved by a 4μs pre-processed treatment after 24h holding period and further processing results revealed that all treatments were effective to increase the total lycopene. Most of juice processing treatments decreased the release of lycopene from the tomato matrix during digestion. Only the treatment of blanching followed by high intensity pulsed electric field showed a significant release of trans-(4.01±0.48) and cis-(5.04±0.26μg/g) lycopene, achieving 15.6% total lycopene bioaccessibility. Thus, processing of pre-blanched juice using high intensity pulsed electric field, derived from pre-processed tomato was the best overall process to achieve the highest nutritive value.

Optimization of salt curing of bitter gourd (Momordica charantia L.) with blanching as pre-treatment using response surface methodology

Purpose Pickling or salt curing is one of the major traditional processes to increase the shelf life of bitter gourd in India. No information is available about optimization of salt curing of bitter gourd and the related changes in its quality. Moreover, specific investigations are needed to evaluate individual susceptibility of fruit and vegetables to osmotic dewatering with pre-treatment to obtain new minimally processed food products. The purpose of this study is to optimize the salt curing process with blanching as pretreatment for bitter gourd. Design/methodology/approach A study was conducted to optimize the blanching and other process factors of salt curing (solution concentration and treatment time) based on mass transfer and quality factors of bitter gourd using response surface methodology. Experimental design was made using central composite rotatable design with different time of blanching, solution concentration and treatment time. The colour, firmness, water activity and other mass transfer kinetic parameters were used for optimization. Findings Blanching had significant effect (p < 0.001) on water loss (WL), weight reduction (WR), solid gain (SG), water activity and firmness of bitter gourd. Mass transfer kinetic parameters like WL, SG and normalized solid content increased and normalized moisture content was found to decrease with increase in solution concentration and curing time. Relationships between process variables and quality factors were established in either quadratic or linear form with higher R2 values. A 15 per cent solution concentration for the period of 5 h with the blanched samples at 800°C for 5.26 min was found to be the optimum condition for osmotic dehydration to achieve maximum WL and SG, minimum water activity and minimum changes in firmness. Practical implications The optimized combinations for the salt curing process would be more helpful for the processors and other stakeholders involved in the pickling process by reducing energy and other input resources. Social implications Mostly in India, the pickling process is carried out at micro- and small-scale level and in an unorganized way. This study would help those involved to reduce their input resources and to organize the process, thus leading to more dividends to the stakeholders and optimum price to the end-users. For the medium- and large-scale processing units, this study would give insight to automate the whole process in an efficient manner. Originality/value This study was performed using sophisticated and higher-end instruments. The data were observed meticulously and analysed with proper statistical tools, increasing the credibility of the study. This study gives concrete results which are directly useful to the stakeholders.

Evaluation of Artichoke Bracts as a Potential Source of Bioactive Compounds, Bio-ethanol Production and Livestock Feeding

Recycling of lignocellulosic agro-industrial residues waste is the key of the environmental sustainability. So, the goal of the present study was to utilize artichoke (Cynara cardunculus L.) bracts as a potential source of bio-active compounds or as a carbon source during bio-production of ethanol and to evaluate its nutritive value for livestock feeding by using in vitro gas production technique. The chemical composition, phenolic compounds, and radicals scavenging property of extracts were determined. Silage production and acid hydrolysis on conversion of lignocellulosicartichoke was studied. Also, the acid hydrolysate of lignocellulosic components as a carbon source was investigatedduring bio-production of ethanol using Saccharomyces cerevisiae and simultaneous saccharification fermentationprocess. The obtained results revealed variation in proximate composition and mineral content among treatments of artichoke bracts used here. The blanching processing of artichoke bracts had higher total phenolic content (935.43 mg GAE /100 g DW) and 89.64% inhibition of DPPH radical with an IC50 value of 6.23 mg/ml. The highest reducing sugar content was obtained by using sulphuric acid (3%) for 20 min at 120°C. Fermentation of the hydrolysates gave the highest ethanol yield of (10.02 g/L), which corresponds to volumetric productivity of ethanol being 1.52 g /L/h with fermentation efficiency of 97.39% and biomass of 4.64 g/L after 48 hr. The results of the present study suggest that adding sugar beet molasses to the fermentation medium enhanced production of bio-ethanol (14.01g/L). The resultsalso showed that the nutritional value of the artichoke bracts is similar to that of good roughage as hay in terms of metabolizable energy (8.42 MJ/kg DM), net energy (3.15MJ/kg DM), short chain fatty acids (99.48 mM), microbial protein synthesis (76.49 g/kg) and organic matter digestibility (63.41 %).

Effects of Blanching on Physicochemical Properties of Chantenay Carrots Juice and Assessing the Qualities of Formulated Carrot-MD2 Pineapple Juice Blends

This study was carried out to determine the effects of three blanching methods on carrots and also to assess the physico-chemical and sensory properties of formulated Chantenay carrot-MD2 pineapple juice blend. Hot water, steam and microwave blanching were the methods used and the respective blanching temperatures were 98, 105 and 75 °C for 10 minutes each. Physicochemical properties determined on the juices extracted by gravity from blanched carrots were yield, pH, total soluble sugars, total solids, ash and vitamin C. There were significant differences (p<0.05) in the yield, vitamin C and total solids of the blanched and unblanched carrots. Steam blanching method was chosen for the formulation of the carrot-pineapple juice blend due to its high yield and ash content of 76.65 and 0.66% respectively. The carrot juice from the steam blanching process was formulated with MD2 pineapple juice into various ratios of 50:50, 60:40, 70:30 and 100:0 with the carrot juice being the major component. A preference ranking test carried out on the formulated carrot-pineapple juices indicated that the 50 untrained panellists mostly preferred the 50:50 formulated juice. Proximate and physicochemical analyses were conducted on the 50:50 formulated carrot-pineapple juice and had the following compositions: fat (0.25%), ash (0.25%), protein (0.78%), crude fibre (2.68%), carbohydrates (23.47%), moisture (72.57%), vitamin C (12.40 mg/100 g), β-carotene (955.71 µg/100 g), pH (4.45), total soluble sugars (14.87%) and titratable acidity (1.50%). In conclusion, development of this product will enhance the utilization of carrot not solely for stews and salads but also as a juice blend with the potential to compete with the local and foreign fruit juices on the market. Consumption of the product will help address the resurgence of nutrition-related chronic diseases due to its appreciable content of β-carotene which are potent free radical scavengers in humans.

Alternative Thawing Methods for the Blanched/Non‐Blanched Potato Cubes: Microwave, Ohmic, and Carbon Fiber Plate Assisted Cabin Thawing

AbstractThe effects of conventional‐C, carbon fiber plate assisted cabinet heater‐CPAC, ohmic‐OT, and microwave thawing‐MT techniques on changes of some quality characteristics and resistant starch (RS) content of potato (Solanum tuberosumL.) cubes (18 × 18 × 18 mm) were investigated. The effects of blanching prior to the freezing on thawing characteristics were also determined. The thawing times of non‐blanched samples were determined as 23,580 ± 485 s, 5360 ± 40 s, 205 ± 18.25 s and 19.26 ± 1.49 s for conventional, CPAC, OT, and MT methods, respectively. The blanching process increased the thawing times in general. OT and CPAC thawing methods served lower RS content for thawed potato samples. The potato cubes thawed by OT and MT were softer than C and CPAC thawed potato cubes (P &lt; 0.05). The highest color change was found for MT of blanched samples and conventional thawing of non‐blanched samples. The electrical methods could be alternative thawing methods in terms of providing shorter thawing times and desirable changes on some quality characteristics.Practical ApplicationsThe conventional thawing of high amount of frozen food products have posed a problem for catering industry. The long thawing time, drip loss issues, quality loses and possible microbial spoilage are lacks of conventional thawing method. The electroheating methods such as ohmic, microwave and unique carbon fiber plate assisted cabinet heating were employed as alternative thawing techniques. Thawing time of potato cubes were shortened and quality characteristics, such as drip loss, texture profile, color properties and resistant starch (RS), were improved by novel thawing methods. The obtained results reveal that the application of alternative thawing methods may lead to decreasing of the operating cost due to shorter process time and minimizing the changes in color, texture and nutritional compounds.

Biochemical Changes of Cubiu Fruits (&amp;lt;i&amp;gt;Solanum sessiliflorum&amp;lt;/i&amp;gt; Dunal, Solanaceae) According to Different Tissue Portions and Ripening Stages

Cubiu fruits (Solanum sessiliflorum Dunal, Solanaceae) are known for their high nutritional value and low caloric content. This work aimed at evaluating biochemical indices of cubiu fruits according to different tissues (peel, pulp and placenta) and ripening stages (green, turning, ripe and fully ripe). The fruits were randomly harvested to investigate sensory aspects (colorimetry, blanching effect, pigments) and biochemical indices (moisture and dry matter, Total Soluble Solids (TSS), pH, Titratable Acidity (TA), TSS/TA ratio, ascorbic acid, Alcohol-Insoluble Solids (AIS), pectinesterase activity and pectin content). The analyses were performed at the laboratory of Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, Brazil. The blanching process preserved pulp colors at all ripening stages. Chlorophylls were higher in green peels; flavonoids and carotenoids, in fully ripe peels. Anthocyanins were entirely absent. Pulp (turning fruits) showed the highest moisture content (91.05), followed by ripe pulp (90.70) and fully ripe pulp (90.62). Pulp TSS changed little whereas placenta TSS declined and were associated with increased TA and pH reduction (fully ripe fruits). Pulp pH and TA varied little whereas placenta pH was notably low and TA was remarkably high (fully ripe fruits). Pulp TSS/TA ratio showed predominance of TSS while in placenta, there was predominance of organic acids. AIS, precursors of pectin, were stable during ripening. The statistical analysis of dietary fiber content showed one modal value in the AIS. In pulp, pectinesterase activity correlated inversely with pectin content. Cubiu fruits were significant sources of bioactive compounds, e.g. chlorophylls, flavonoids and carotenoids, predominantly in the peel and the pulp; soluble functional fibers, e.g. pectin (g/100 g fresh weight), particularly in the green peel (1.00) and the fully ripe pulp (1.12), and other versatile molecules, e.g. ascorbic acid (mg/100 g fresh weight), especially in the fully ripe peel (32.45) and placenta (24.84) and the turning placenta (21.27). Cubiu fruits are rich in ascorbic acid and should be included in the human diet.

Combined Effects of Gamma Irradiation and Blanching Process on Acrylamide Content in Fried Potato Strips

Potato tubers were irradiated in 60Co gamma station at different doses in order to investigate the effect of gamma irradiation on acrylamide formation in fried potato strips. Acrylamide content due to the irradiation treatment was reduced by 20–54% compared to a control after frying the irradiated tubers. While apply a blanching process, using warm tap water, to potato strips before frying has decreased acrylamide by 61%. A combination of gamma irradiation and a blanching process, which was applied in this work, showed a maximum decrease in acrylamide formation to reach 78% in fried potatoes.

NMR Relaxometry and Imaging to Study Water Dynamics during Soaking and Blanching of Soybean

Abstract In the present study, soaking and blanching soybean were studied by time-domain nuclear magnetic resonance (TD-NMR) relaxometry and magnetic resonance imaging (MRI). Four proton fractions with different mobilities were observed in dried, soaked and blanched soybean samples, which reflects macromolecule, oil and water in different microenvironment of soybean. The proton distribution of soybean was significantly changed during soaking process. According to the result of MRI, water may initially penetrated into soybean from its radicle and micropyle. In terms of water distribution, the optimum soaking time for soybean was appeared to be 8 h. Blanching also significantly changed the proton distribution of soybean. During blanching, all four proton fractions became more mobile, and the accumulation of extracellular water was observed due to the partial destruction of cell/membrane integrity. The heat-induced variations of cotyledon tissues structure mainly occurred in the first 30 min, which implied blanching process should last at least for 30 min.

Modeling of Peroxidase Inactivation and Temperature Profile During Infrared Blanching of Red Bell Pepper

Infrared (IR) blanching resulted in moisture loss (∼1.6%), whereas fat, crude fiber, protein and carbohydrate contents were not affected. Retention of ascorbic acid (94.3%) and β-carotene (108.4%) was found to be high after IR blanching. Inactivation of peroxidase (POD) and temperature profile in red bell pepper was predicted by employing different models. Fractional conversion model and multiple regression analysis were used to predict the POD inactivation at different temperatures (130, 150 and 170C). The time–temperature–distance relationship and multiple regression analysis were used to predict the temperature at different points (0.5, 2.5 and 4.5 mm from top) of red bell pepper subjected to IR blanching at 150C. The multiple regression analysis was found to fit well (R2 = 0.996–0.997) with the experimental values for predicting POD inactivation than fractional conversion model (R2 = 0.868–0.943). The temperature profile during blanching of red bell pepper was predicted well by using time–temperature–distance relationship (R2 = 0.996–0.999) and multiple regression analysis (R2 = 0.979–0.989). Practical Applications Infrared (IR)-based dry blanching offers advantages such as higher retention of water-soluble nutrients, complete elimination of effluent generation, higher energy efficiency, and both blanching and drying operations in the same processing unit, which minimizes labor requirement and improves productivity. The present study showed that IR can be effectively used for peroxidase inactivation in red bell pepper at different processing temperatures. The quality of IR-blanched red bell pepper in terms of ascorbic acid, β-carotene, carbohydrates, protein, ash, fiber and moisture content was not affected significantly. Peroxidase inactivation during IR blanching is temperature dependent and it is essential to know the distribution of temperature in the material being processed to standardize the operating conditions. The inactivation rate constant and decimal reduction time of enzyme provide information to design a blanching process efficiently. This research area has been a scope for further studies and this technique can replace conventional water blanching.

Influence of different blanching methods on colour, ascorbic acid and phenolics content of broccoli.

Lack of nutrients in cooking water, high energetic costs, high water consumption and recycling are some drawbacks of vegetable blanching. Those disadvantages could be bypassed using microwave blanching. Three blanching methods (microwave, boiling water and steaming) were compared in this study in order to determine their effects on some functional properties of broccoli. In addition, the thermal damage on broccoli colour was evaluated. The effectiveness of each blanching process was performed measuring the lost of peroxidase activity, that results more rapidly in microwaves and steam treatments (50 and 60s respectively) than in boiling water treatment (120s). The colour indexes did not allow to discriminate a significant difference among treatments. The increase of treatment time caused a vitamin C decrease in samples blanched by boiling water and steam; this trend was not observed in microwaved samples. The phenols content did not significantly vary depending both on type and on time of treatment.

Effects of Blanching on Flavanones and Microstructure of Citrus aurantium Peels

Water and steam blanching were investigated as pretreatments of bitter orange peels in order to modulate their bitterness before further formulation processing such as osmotic treatment and drying. The fruit pieces were water blanched at 95 °C for 10 min and at 85 °C for 60 min and steam blanched at atmospheric pressure during 5 min. The kinetics of water inflow and bitter flavanone losses were established from the variation of moisture and bitter compound contents during the blanching process. The whiteness and the citrus color indexes were adopted to evaluate respectively the color of the flavedo and the albedo. Thin sections of fresh and treated peels were resin embedded for light microscopy evaluation and optical porosity determination. Results revealed that water blanching could partially debitter the peels by removing about 38 and 48 % of bitter flavanones (naringin, neohesperidin, neoeriocitrin) respectively at 95 and 85 °C. The citrus color index and the whiteness index decreased during the process denoting a flavedo discoloring and an albedo darkening. By contrast, the steam blanching showed good retention of bitter compounds. The color of the flavedo was unaffected by steaming while the whiteness index decreased. At microscopic level, the water-blanched peels exhibited an extreme swelling of the cell walls and slight disintegration of the tissue. Contrariwise, the steam blanching maintained the structure of the peels and brought about the shrinkage of the albedo tissue and the decrease of porosity.

Efficiency assessment of blanching and deep-freezing systems through data envelopment analysis

The aim of this paper is to define the blancher-freezer combination best fitting with the preservation treatment of a specific food. The proposed approach in decision making is based on the data envelopment analysis (DEA). Through the Cross efficiency evaluation, each decision making unit (DMU) is both self-evaluated and also evaluated via the other DMUs. Cross efficiency provides an efficiency ordering among all the DMUs, with a high discrimination power, avoiding potentially unrealistic weighting schemes. The efficiency, used for ranking and selecting the systems, is a function of the used resources (input values) and the resulting outcomes of each DMUs activity (output values). An interdisciplinary working group defined the proper set of input and output. As concern the blanching process, the selected input parameters are electric power consumption, steam consumption, water consumption, wastewaters, Biochemical Oxygen Demand and Peroxidase; the selected output parameters are residual Vitamin C and plant throughput. As concern the freezing process, the selected input parameters are electric power consumption, freezing capacity, dehydration and freezing time; the selected output parameter is the plant throughput. The proposed approach can be implemented to establish the ideal blancher/freezer selection also in the event of the need to include into selection other parameters or other food treatment systems.

EFECTO DEL PROCESAMIENTO TÉRMICO SOBRE EL COLOR SUPERFICIAL DELPIMENTÓN ROJO (Capsicum annuum)VARIEDAD “NATALY ”

Color is one of the most important parameters when measuring the quality of products to be processed from red pepper (Capsicum annuum), for the manufacture of seasonings, colorants, preserves and dressings. In this study, the effect of thermal processing (fried and canned) was evaluated with respect to color change and carotenoids in fruits of red pepper. For frying soybean oil was used at a temperature of 175°C for 5 min; in the development of conservation as a process of blanching and pasteurization was carried out at 100°C for 15 min. After heat treatment (frying and preserves) the concentration of total carotenoids and surface color of red pepper fruits significantly affected. The frying process obtains the highest average values of ASTA (72,214) Total Carotenoids (95,464), L* (38,26) and (34,13). The registry retains the highest color attributes b* (21,81), h° (30,42), IP (145,40) and ΔE* (4,56 to 31,84). These results show that frying is an operation that improves the color attribute, by increasing the availability of carotenoids and increase the surface color a*.

Determination of Lovastatin, β-glucan, Total Polyphenols, and Antioxidant Activity in Raw and Processed Oyster Culinary-Medicinal Mushroom, Pleurotus ostreatus (Higher Basidiomycetes).

The objective of this study was to quantify a number of bioactive compounds and antioxidant activity of the oyster mushroom, Pleurotus. Ostreatus, and characterize the effects of processing, such as blanching, on these outcomes. Dry matter content was 8%. Lovastatin was not detected in this study. β-glucan content of 23.9% and total polyphenol content of 487.12 mg gallic acid equivalent/100 g of dry matter were obtained in raw P. ostreatus. Antioxidant activities as evaluated by 1,1-diphenyl-2-picrylhydrazyl, Trolox equivalent antioxidant capacity, and ferric reducing antioxidant power assays in raw P. ostreatus were 14.46, 16.51, and 11.21 µmol/g, respectively. Blanching did not significantly affect β-glucan content but caused significant decrease in dry matter content, polyphenol content, and antioxidant activities. Mushroom rolls produced from blanched mushrooms and blanching water contained significantly higher amounts of β-glucan, total polyphenol content, and FRAP antioxidant activity compared to blanched mushrooms. In conclusion, P. ostreatus is a good source for β-glucan, dietary polyphenols, and antioxidants. Although the blanching process could affect these properties, re-addition of the blanching water during the production process of mushroom rolls could potentially recover these properties and is therefore recommended.

블랜칭 및 용질 처리에 따른 참취(Aster scaber Thunb.)의 phytochemical 성분 및 품질특성

The quality characteristics of blanched Aster scaber with the blanching condition and various solutes (non-treated, NT; soluble Ca, SC; sodium bicarbonate, SB; and magnesium sulfate, MS) were evaluated with different blanching times and solutes. The blanching process decreased the total polyphenolics, ascorbic acid contents, hardness, and cutting strength of the leaves. As for the pectinesterase and polygalacturonase, the blanching process increased their inhibitory activities, and more than 90% of them were inactivated in all the samples that were blanched. For the total counts and the number of coliform groups, the number of total aerobes at 5.92-log CFU/g before the blanching process was reduced to the approximately 2-3 log scale, and the coliform group was not detected after the blanching. The blanching also significantly decreased the total chlorophyll a and b ratios. The sensory characteristics of the Aster scaber according to the test group showed that the leaves blanched for 3 min were the most highly evaluated in terms of their overall acceptability. The phenolic compound, chlorophyll, and carotenoid contents tended to increase from before their blanching, and the Ca/Cb ratio was higher in the SC. These results showed that SC and MS treatment had greater effects on the quality characteristics and the pigmentation.