Band 7, Heft 1

In attempt to develop an effective strategy to obtain douchi with anti-?-glucosidase functionality, Bacillus subtilis B2 was used as the initial microorganism to produce bacterial-type douchi koji capable of inhibiting ?-glucosidase activity in the current study. Various fermentation conditions, such as soybean type, fermentation time and humidity, resulted in different anti-?-glucosidase activity of the douchi koji. Regardless of soybean or black bean, the douchi koji exhibited a drastic increase in anti-?-glucosidase activity during the first 48 h of fermentation and kept a slight increase from 48 h to 96 h. The anti-?-glucosidase activities of both soybean and black bean kojis displaying the lowest at the relative humidity of 70 percent, rose up to the highest at the humidity of 90 percent and then showed a slight decrease. Under the same fermentation conditions, it is found that the soybean douchi koji exhibited higher ?-glucosidase inhibitory activity than that of black bean douchi koji. Maltose, sucrose and glucose were reduced drastically in soybean and black soybean koji after 96 h of fermentation. One of the most effective ?-glucosidase inhibitors, deoxynojirimycin (DNJ), with promising biological activity was observed both in the soybean koji and black soybean koji, which provide an inspiring strategy to produce DNJ-derived foods with low content of saccharides for the diabetic patients.

In this paper, the influence of sample geometry and different solar drying conditions on mass transfer evaluation at food-air interface, hm obtained from different approaches is experimentally investigated. Two different approaches of hm estimation used in the analysis are based on the measurement of moisture loss rate data (direct method) and graphically computed values of drying parameters and moisture diffusion coefficient (indirect method). Drying experiments were performed with potato cylinders and slices of same thickness of 0.01 m with their respective length and diameter of 0.05 m using natural convection mixed-mode solar dryer and open air sun drying conditions. Results of analysis reveal that for each method of estimation, the cylinders vis-à-vis slices produce higher values of hm for both the solar drying conditions. It is also found that the mixed-mode solar drying enhances moisture transfer at food-air interface for each of the sample geometry as expected. Out of the two approaches investigated for hm estimation, the indirect method exhibits lower values of hm and these values are found to be more close to the results reported in the literature. The present analysis also indicates that Chilton-Colburn analogy for heat-mass convection does not hold well in the natural convection air drying of food product.

The aim of this study was to compare the effects of different storage temperatures (+2°C, -4°C, -12°C, -18°C and -24°C) and time (0, 1, 3 and 6 weeks) on the quality of heavily salted cod. The color, water content, water holding capacity (WHC), cooking yield, total volatile basic nitrogen (TVB-N) and trimethylamine (TMA) of the samples were determined. Results showed that the whiteness of the salted cod decreased slightly, whereas the yellow/orange color increased during the storage period. The WHC and cooking yield increased and were inversely related to water content. The TVB-N value increased slightly, whilst a lightly decrease in TMA value was observed. Storage at -4°C and lower temperatures had a detrimental influence on the color of the product which is the main quality criterion for salted cod. Therefore, it is not suitable to store the product at -4°C or lower temperatures.

An analytical diffusion model which considers the influence of the external resistance to mass transfer, sample finite geometry and shrinkage is proposed to simulate drying kinetic curves of cylindrical bodies. The convective mass transfer coefficients, hm at air-solid interface obtained from natural convection drying experiments on potato cylinders of length 0.05m and diameter 0.01m at different air drying temperatures were used for the model evaluation. Using Levenberg-Marquardt algorithm for optimization, an empirical relation describing effective diffusion coefficient of potato as a function of air temperature and material moisture content is proposed for finite and infinite cylinders with and without considering shrinkage. The significance of material moisture content in the proposed diffusion coefficient relation is demonstrated through a comparison between the predicted and experimental moisture content ratios. The mean effective diffusion coefficient, Deff for finite shrinking cylindrical bodies is found to vary from 3.93 to 8.63 x 10-10 m2/s for the temperature range of 40 to 60°C. In addition, the assumption of infinite geometry instead of finite one in the model evaluation results in an overestimation of Deff. However, lower values of Deff are obtained when shrinkage effect is taken into account in the analysis, irrespective of the product size considered.

An investigation was carried out to determine the effects of some factors on the production of effervescent artichoke tea tablets from dried artichoke (Cynara scolymus L.): extraction solvent composition, extraction temperature, extraction time, ratios of leaf, flower, stalk and root of dried artichoke, concentration of spray-drying solution, spray-drying temperature, spray-drying carrier, concentration of spray-drying carrier, proportion of effervescent agent, and components proportion of effervescent agent. The recommended extraction solvent was water with 10 percent of ethanol 96 percent (v/v), with an extraction temperature of 100°C, soak time of 14 hours, first extraction time of one hour, second extraction time of three hours. The dried artichoke raw material consisted of 1.0 parts leaf, 0.5 parts flower, 1.0 parts stalk and 1.5 parts root. The recommended concentration of spray-drying solution was 20 percent, spray-drying temperature of 150°C, spray-drying carrier was maltodextrin at a concentration of 10 percent. The recommended effervescent agent consisted of 1.0 parts citric acid, 1.0 parts tartaric acid and 2.44 parts sodium bicarbonate, added at 45 percent of total weight of effervescent tablet.

Statistical experimental design strategy (SES) was employed to optimize the culture conditions for the mycelial growth of C. militaris by submerged culture. Using Plackett-Burman design (PBD), liquid volumes in flask and fermentation time were identified as the significant variables that would highly influence mycelial growth, and these variables were subsequently optimized using response surface method (RSM). The steepest ascent method was used to access the optimal region of the culture condition. The results showed that the optimum values of the tested variables were 47.3 mL of liquid volumes in flask and 7.6 days of fermentation time. Under optimized culture conditions, the mycelial production was enhanced from 10.33 to 19.97 g/L. In comparison with that of original culture conditions, 1.9-fold increase was obtained. The validation experiment showed that the experimentally determined production values were in close agreement with the statistically predicted ones.

This paper presents the suitability of feature extraction methods for the identification and classification of certain agriculture and horticulture crops. Primarily, agriculture/horticulture crops are recognized based on their shape, size, color, texture and the like. When crops exhibit different shapes and sizes, it is customary to choose the shape and size as the basic features. Certain crops are easily identified simply by color; for example, with crops like jowar, ground nut, pomegranate and mango, color becomes the discriminating feature. We have considered color as one of the features in this study. Some agriculture/horticulture crops have overlapping colors, such as wheat and ground nut or mango and orange. When we consider the bulk samples of such grains or fruits, the surface patterns vary from crop to crop. In such cases, the texture becomes ideal for recognition. Hence, we have obtained morphological features, like shape and size, color and textural features, of the image samples to recognize, classify and grade the agriculture/horticulture crops.

Hydrodistillation is a potentially useful method to extract essential oil from various plant materials and was used to separate essential oil from Cymbopogon flexuosus (lemongrass). The yield is dependent on various parameters like weight of raw material, volume of water, size of raw material and nature of raw material. The purpose of this study was to find the optimum values of these parameters. The optimized conditions for the extraction were 50 g of raw material, 500 ml of water volume, plant size of 25 mm, and the yield obtained was 1.04 percent. The loss of about nine percent essential oil was observed during drying of leaves of lemongrass. Composition of the essential oil was analyzed by GC-MS and higher amount of oxygenated compounds, mainly citral, was found in each sample. There was not much variation observed in amount of citral. The results indicated that hydrodistillation may further be utilized for scale up studies.

This paper presents the outcomes of a comprehensive and detailed analysis of the Italian food market, targeting the Fast Moving Consumer Goods products and aimed at defining the existing relationships between product characteristics and packaging technologies. A sample of 175 products has been examined, and the corresponding characteristics and packaging technologies were derived from an in-field investigation performed in large and small Italian retailers. Subsequent statistical analyses were first focused on providing descriptive statistics concerning the packaging materials used for food products. Then, cluster analysis was exploited to group products on the basis of the material used for the primary packaging. Discriminant analysis was also adopted to identify product characteristics that significantly contribute to the choice of packaging material. Finally, based on the clusters obtained, contingency tables were used to explore possible relationships among packaging material, packaging techniques and relevant product characteristics. Results of this study could provide useful guidelines to food manufacturers to identify the most suitable packaging technology for new food products.

One of the most interesting and desirable of all tropical fruits is sapodilla, a member of the family Sapotaceae. In the present study, a new and economical method has been developed for value addition to this fruit into a neutraceutical ready-to-eat formulation using drying as the main step. The drying of sapota fruit was carried out in two steps. In the first step, blanched sapota pulp was partially dried (up to moisture content 32 percent w/w on wet basis) in a convective dryer. The effect of different additives on the drying kinetics was studied and then proper drying conditions were selected. In the second step, different nutritional additives of interest were mixed with this partially dried pulp; subsequently, this mixture was extruded to a variety of shapes, which were finally dried using either a convective dryer or a fluidized bed dryer. The product quality was compared on the basis of color retention, texture, water activity, glucose content, total protein content, bulk density, water solubility index, water absorption index and sensory analysis. The process has a great potential since it is economical and provides a great value addition to the highly perishable sapota fruit.

An isostatic pressure system was used to treat fresh-squeezed orange juice inoculated with Saccharomyces cerevisiae, Escherichia coli, and Listeria innocua for selected times (come-up time, CUT, to 15 min plus CUT) and pressures (103 - 414 MPa). Specific agars, for each type of microorganism, were used for pour plating to count survivors after pressure treatment. Decimal reduction time values (Dp) were calculated from the first order kinetics modeling for S. cerevisiae (103-241 MPa), E. coli (103-241 MPa), and L. innocua (103-345 MPa) survivors in juice. Dp values of 6.1–52.1, 0.6–14.9, and 4.8–357.1 min were obtained for S. cerevisiae, E. coli, and L. innocua, respectively. zp values of 147.1, 92.6, and 59.2 MPa were calculated for these microorganisms, respectively. The come-up time (CUT, time required to reach the processing pressure), had an important effect on the microbial reduction. The initial counts of 5.3 x 105, 1.2 x 107, and 2.6 x 107 CFU/mL were reduced by 30, 88, and 27 percent for S. cerevisiae, E. coli, and L. innocua, respectively, at 241 MPa, after 1.2, 3.0 and 1.8 min of processing, respectively. However, no survivors were observed (<10 CFU>/mL) for the three types of microorganisms when processing at 241 MPa for times longer than 3 min or pressures higher than 241 MPa.

In this research, the effective parameters on Ohmic heating in aseptic and heating applications were studied. For this purpose, two- and three-dimensional Ohmic heating models in a two phase bio-solid-liquid system were developed. In these models, effects of particles distribution, particles size, effect of electrical conductivity on heating, overall heating of mixture and effect of salt concentration on heating rate were investigated. Temperature distribution profile, effects of intensity and distribution of electrical field on total temperature, and type of salt on phase electrical conductivity was also investigated. The modeling equation was solved with Finite Elements Method. The results showed that in Ohmic heating, heat diffusion in entire products was faster than the conventional methods, and it was accomplished with almost an equal rate in both phases.

In order to determine the potential for the reduction of nitrite level and ripening period with heat treatment, the effects of the ripening period (1-13 days), nitrite level (45-195 ppm) and heat treatment (30-90°C) on yield, moisture, fat and protein contents of sucuk were investigated using response surface methodology (RSM). Ripening period was found to be the main factor affecting the studied parameters of sucuk (p < 0.01). Moisture and yield decreased with increasing ripening period; however, fat and protein values increased with increasing ripening period. Higher levels of heat treatment, particularly above 60°C, increased protein values and decreased yield values. The changes in the studied parameters caused by additional nitrite levels were not found to be significant (p > 0.05). When considered in terms of proximate composition of sucuk, it can be said that it is possible to reduce the nitrite level and ripening period with certain levels of heat treatment in sucuk.

Ten Indian herbs (Manjisth, Tagar, Kulfa, Khuskhus, Gokharu, Carrot, Kasni, Bathua, Soya ke Beej, Pudina), popularly used for medicinal purpose, were extracted in sonicator by methanol and water for the estimation of polyphenols and flavonoids. Antioxidant capacities (AOC) of extracts were evaluated based on their ability to scavenge the DPPH radical and FRAP Assay. The results showed that methanolic extract of all the plant materials had very high antioxidant activity. Amongst them, Pudina extract in the methanol showed highest value of AOC by both FRAP and DPPH methods (33 percent and 1.36 mg QEq / 100 g). Total phenol and flavonoids content were also evaluated for these extracts. It varied from 0.8736 to 6.3918 mg GAE / 100 g and 0.3642 to 1.9876 mg QE / 100 g. Total ash content and acid insoluble content of soya showed highest value i.e. 14.55 percent and 92.92 percent.

The aim of this work is to develop a membrane-based cost-effective process for the rapid isolation of immunoglobulin from chicken egg yolk. It was found that a single-stage ultrafiltration using a 100 kDa molecular weight cut-off regenerated cellulose membrane could be employed to isolate immunoglobulin from the crude feedstock. The effects of operational parameters (solution pH, ionic strength, stirring speed and permeate flux) on the transmission of immunoglobulin and the presence of impurity protein with molecular weight close to immunoglobulin were quantified using the parameter scanning ultrafiltration technique. Under optimized conditions, the purity of immunoglobulin obtained was about 85 percent after the single-stage ultrafiltration process, and the recovery of immunoglobulin from the feedstock was 91 percent.

The present work has employed an optimization process among experimental temperatures and those obtained by finite elements analysis (FEA) for the determination of the convective heat transfer coefficient (h) during a stand up retortable pouch process in a steam-air retort. The process was divided in four periods, and the values obtained were: 828.7 W.m-2.K-1 (hh1, first portion of heating; come up time); 538.5 W.m-2.K-1 (hh2, second portion of heating; ball time); 1293.6 W.m-2.K-1 (hc1, first phase of cooling); and 183.6 W.m-2.K-1 (hc2, second phase of cooling). The results obtained were validated experimentally by meat product sterilization, presenting good correlation between experimental values and those obtained by the model. The values obtained contribute to the studies of heat transfer and thermal processes; besides, its values for pouches processes are scarce in the literature.

Betel is a native medicinal plant from central and eastern parts of Peninsular Malaysia. It is now an important commercial crop in India and Sri Lanka. There are various beneficial bioactivities discovered in this herb including anti-carcinogenic, anti-inflammatory, antioxidant, and antimicrobial properties. Freeze drying is one of the common methods used to dehydrate the herbal aqueous extract. This work studied the freezing process of aqueous extract of betel leaves (Piper betle L.). The effects of different freezing temperatures on the freezing kinetics were investigated. Freezing temperatures of -20, -25, -30°C were selected for the study. The freezing time which was taken as the time required for the temperature of the sample to reach the freezing temperature was determined from the kinetics data. The freezing point of betel leaves extract was determined as -4°C. The freezing process was described with numerical model. The predicted data showed good agreement with the experimental results.