Fractionation of rosemary ( Rosmarinus officinalis L.) essential oil using vacuum fractional distillation Abstract Rosemary essential oil has many compounds suitable for use in the food, cosmetics and pharmaceuticals industries. This study aimed to evaluate vacuum fractional distillation to separate and purify components of rosemary oil, also to observe the distillation patterns. The light terpenes (α-pinene, myrcene, camphene) were removed at the top of the column, while the oxygen containing components (verbenone, borneol, linalool, geraniol) remained at the bottom. The concentrations of some minor compounds increased more than ten times (borneol, geraniol) compared with the raw oil. There was no evidence of thermal degradation in any of the experiments. Therefore, vacuum fractional distillation may be an interesting process to upgrade rosemary essential oil.

Determination of sensitivity of some food pathogens to spice extracts Abstract Spices are primarily used as flavor enhancers and have attracted attention as natural food preservatives since their antimicrobial effects were determined. In the present study, the antimicrobial effects, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values on 5 important food-borne pathogenic bacteria were investigated in 20 different types of spices that are not commonly used. The results indicated that Hibiscus (Hibiscus sabdariffa) was the most effective against Listeria monocytogenes (26.37 mm zone diameter) and Staphylococcus aureus (24.15 mm zone diameter) (P < 0.05) followed by the chebulic myrobalan (Terminalia chebula) (21.34 ± 0.35 and 23.85 ± 1.69 mm diameter zone respectively) (P < 0.05). Likewise, Hibiscus (H. sabdariffa) showed the lowest MICs and MBCs concentration values on five important food-borne pathogens (L. monocytogenes) MIC; 0.187 mg/L, MBC; 0. Thus, this study determined that spices with antimicrobial activities can be used as natural preservatives.

Antioxidant activity of Pistacia atlantica var mutica kernel oil and it’s unsaponifiable matters Abstract In this research, antioxidant activity of Pistacia atlantica var mutica (a wild type of pistachio in Iran) kernel oil (PAKO) and unsaponifiable matters of kernel oil (UKO) were compared with those of sesame seed oil (SSO) and rice bran oil (RBO) as well as with their unsaponifiable matters (USO and UBO) and α-tocopherol (natural antioxidant) was selected as control. Also, some chemical properties such as (FRAP, DPPH radical-scavenging, rancimat and oven assays (peroxide value and carbonyl value) were assessed. The amount of unsaponifiable matters of studied oils was between 1.4 and 3.5%. The highest total phenolics was observed in SSO (1024 mg/kg), followed by RBO, and PAKO was 174, and 75 mg/kg, respectively. In DPPH radical-scavenging assay, the EC50 values of PAKO, SSO, RBO, UKO, USO, UBO, and α-tocopherol were determined as 38.9, 50, 48.4, 14, 12.7, 15.9 and 61.4 mg/mL, respectively. In FRAP assay, the highest value was nominated for UKO (434 mmol/L); followed by USO, UBO, PAKO, SSO, RBO and α-tocopherol (404, 357, 364, 298, 210 and 58 mmol/L; respectively). Also, considering the results of oven test, the incorporation of UKO into pure sunflower oil resulted in the highest oxidative stability; followed by UBO, USO, PAKO, SSO, RBO and α-tocopherol. According to results of the rancimat test, the incorporation of unsaponifiable matters (UKO, USO, and UBO) resulted in the highest oil/oxidative stability index (OSI) in pure sunflower oil, followed by oils studied (PAKO, SSO, and RBO). According to results, UKO had the highest antioxidant activity, followed by USO, UBO, PAKO, SSO, RBO, and α-tocopherol.

Volatile profile of fermented sausages with commercial probiotic strains and fructooligosaccharides Abstract The effect of the partial substitution of pork back fat by fructooligosaccharides (FOS) and the probiotic strains Lactobacillus paracasei and Lactobacillus rhmanosus on the generation of volatile organic compounds in fermented sausages was investigated. The results obtained showed that these factors significantly affected the total content of organic volatile compounds (7484, 8114, 8372 and 10,737 AU × 104/g for FOS.GG, CON, FOS.BGP1 and FOS samples, respectively). A total of 59 volatile components, mainly hydrocarbons, ketones and esters were isolated. The reduction of fat content by including FOS in the formulation results in positive effects and a greater stability of the volatile profile of the fermented sausages, increasing ester compounds and reducing the undesirable notes of hexanal (probiotic samples showed values < 2 AU × 104/g). Moreover, there was a symbiotic effect when the aforementioned prebiotic fiber was combined with probiotic Lactobacillus strains.

Development and characterization of blends formulated with banana peel and banana pulp for the production of blends powders rich in antioxidant properties Abstract The food product industry is increasingly looking for foods with nutritional properties that can provide health benefits. Additionally, a challenge for the food industry is the use of all raw materials. For these reasons, banana peel that is a raw material from Banana (Musa spp.) fruit emerges as potential for new food product development. Here, we developed powder blends using a lyophilization process for the preparation of flour to potential use in cookies, bread, and pasta products. Three formulations were designed; the main difference in the formulations was the use of banana peel concentration. Our results showed that blends produced with banana peel presented physical–chemical properties considered suitable for use in food industry. Moreover, the evaluated morphological parameters reveal the properties of the powders. The blends formulated with banana peel have more antioxidant properties, showing that the banana peel may be an attractive option to generate powders with high antioxidant properties.

Application of image analysis technique to determine cleaning of ohmic heating system for milk Abstract Cleaning of equipment is one of the major areas of concern in food industry. Image analysis technique was used to assess the cleaning effectiveness and optimize the CIP protocol for ohmic heating setup. Process parameters selected for optimization of cleaning were caustic concentration (1.0, 1.5, 2.0 and 2.5%), caustic temperature (70, 75, 80 and 85 °C), acid concentration (0.00, 0.25, 0.5 and 0.75%), and acid temperature (40, 50, 60 and 70 °C). Time for caustic treatment was varied from 5 to 20 min at an interval of 5 min, while time acid treatment was kept at a constant of 10 min. Taguchi orthogonal array design was used generate different combinations of acid and alkali concentration and temperature. Images of ohmic heating plates were taken before and after the cleaning procedure. MATLAB program was developed to analyze and extract Gray-Level Co-occurrence (GLCM) matrix properties from the image. Optimized combination was selected based on the highest value of desirability factor among all the experimental set of trials. Treatment with 1.5% caustic concentration at 70 °C for 5 min followed by 0.5% nitric acid concentration at 60 °C was found optimum effective CIP of the heating plates used in ohmic heating setup. GLCM properties correlation, cluster prominence, cluster shade, entropy, homogeneity and inverse difference moment normalized were found suitable for analysis of cleaning effectiveness and optimization of the CIP protocol.

Experimental validation and evaluation of electronic sensing techniques for rapid discrimination of electron-beam, γ-ray, and X-ray irradiated dried green onions ( Allium fistulosum ) Abstract This study focuses on applicability of e-sensing methods in addition to direct epifluorescent filter technique (DEFT), aerobic plate counts (APC), and photostimulated luminescence (PSL) to discriminate e-beam, γ-ray, and X-ray irradiated green onions (scallions) at 1, 4, and 7 kGy for each irradiation treatment, along with two confirmatory analysis. Although low dose (1 kGy) reduced the APC (6.15–2.69 log CFU/g), no significant difference was observed in DEFT. Scallions with log DEFT/APC ratio of ≥ 5.2 can be suspected as irradiated at at least 1 kGy. Both non-irradiated (< 700 counts/min) and irradiated (> 5000 counts/min) scallions were identified by PSL. Besides distinct volatile compounds profile, cumulative e-nose discrimination of 92.06% from principle component analysis was apparent among irradiation conditions. Sensitivity to changes in perceived taste by e-tongue showed 96.07% variation. The e-sensing capability to discriminate irradiated scallions can be exploited for exposing counterfeit claims as either non-irradiated or irradiated within the recommended standards.

Light irradiation can regulate the growth characteristics and metabolites compositions of Rhodotorula mucilaginosa Abstract Light is an important factor that can induce the growth of varieties of organisms including fungi and their secondary metabolites. The evolutions of biomass, carotenoids, lipid production, compositions and contents of fatty acid and amino acid in Rhodotorula mucilaginosa were investigated under different light irradiation conditions. The results indicated that irradiation with 1700 lx could promote the growth and glucose assimilation of R. mucilaginosa, compared to the dark control, while the trial with 3500 lx had certain inhibiting effects. The carotenoids concentrations and percentages of unsaturated fatty acid (USFA, C16:1 and C18:1) increased with the improvement of irradiation intensity. Conversely, the proportions of saturated fatty acids (C16:0, C18:0 and C20:0) were decreased. The relative contents of amino acid and total protein were reduced under illumination compared to dark control. Conclusively, irradiation could change the cell growth and metabolites of the pigmented fungus, which implied that there may be a photoinduced mode exists in R. mucilaginosa similar to that of Neurospora crassa, and it also could be applied to regulate the biosynthesis and production of valuable components such as carotenoids and USFA.

Comparison of the antimicrobial activity of propolis extracts obtained by means of various extraction methods Abstract The objective of the study was to compare the antimicrobial activities of ethanolic propolis extracts obtained using different extraction methods. Extraction of propolis was carried out using 70% ethanol, propolis to ethanol ratios of 1:10 and 1:5, extraction times of 1 or 7 days, and shaking extraction (SE), ultrasound-assisted extraction (UAE), and ultrasound-assisted shaking extraction (SUAE) methods. A total of 12 propolis extract lyophilizates were obtained. Samples were tested for extraction yield and for total phenol content by the Folin–Ciocalteau colourimetric method, and total flavonoid content using a spectrophotometric method. GLC/MS was used for the identification of chemical compounds in selected extract lyophilizates. Antimicrobial activity against selected bacterial and fungal species was assessed using the disk diffusion method. Propolis extracts obtained as the result of 1-day and 7-day shaking extraction followed by 20 min of ultrasound-assisted extraction (SUAE) had better antimicrobial properties as compared to those obtained by SE or UAE alone. SE and UAE gave lower extraction yields as well as lower phenol and flavonoid contents compared to SUAE. No differences were observed with regard to the qualitative composition of extracts obtained by any of the methods. It is best to obtain the extract using the combined method of 1-day extraction and 20-min sonication.

Effect of pretreatment on bioactive compounds in wild rocket juice Abstract The aim of the study was to determine the effect of pretreatment with hot water or steaming on glucosinolates, polyphenols contents and antioxidant capacity in obtained raw juices. Moreover, in vitro cytotoxic activity of the raw juice to the cells derived from the gastrointestinal tract, including the small intestine (IEC-6 cell line), colon (Caco-2 cell line) and the liver (HepG2 cell line) were also investigated. The dominant glucosinolates in the wild rocket leaves were glucoraphanin (36%) and dimeric 4-mercaptobutyl (30%), followed by glucosativin and glucoerucin, 11% per each. Glucothiobeinin (6%), glucobrassicin (1%), 4-methoxyglucobrassicin (1%) and two unidentified compounds (4%) were also detected in rocket leaves. In terms of phenolic compounds, quercetin constituted the majority (55%) and the rest composed of hydroxycinnamic acids. In raw juices produced from steamed, pretreatment with hot water and untreated (control) leaves, glucosinolate contents were lower about 21%, 37% and 53%, respectively, than their levels in the raw material. The highest content of polyphenols among the juices tested (45.4 mg/100 g fresh weight) and antioxidant capacity (5.8 µmol Trolox/1 g f.w.) was recorded in the raw juice from pretreated leaves with hot water. The wild rocket raw juice concentrations responsible for a 50% reduction in Caco-2 and HepG2 cell viability were estimated at 1.87 ± 0.08 mg/mL and 3.54 ± 0.29 mg/mL. The viability of the IEC-6 cells was reduced by only 19.04%, at the maximum concentration (3.6 mg/mL) of the raw juice.