Evaluation of a microbiological method for detection of irradiation of spices

The suitability of a microbiological method, a combination of the direct epifluorescent filter technique (DEFT) and the total aerobic plate count (APC), for the detection of irradiation of spices was evaluated. The evaluation was carried out using different kinds of spices including peppers, paprika, cardamom, cinnamon, ginger; herbs such as thyme, marjoram, basil, and oregano; and garlic powder. Ground spices were tested as well as cut and whole spice samples. Samples were analysed before and after gamma-irradiation mainly with doses of 5 and 10 kGy. Two different methods (centrifugation, filtration) for sample pretreatment were compared. Differences between the DEFT count and the APC with doses of 5 and 10 kGy varied between 3.9 and 6.8 and between 5.7 and 7.5 log units, respectively. The duration of storage after irradiation had no effect on the microbiological results. When applied to fumigated samples, the method might cause confusion in the absence of chemical analyses. The results of the analyses of samples treated by an unknown process indicated that the method could, in fact, detect irradiated samples, although it could not differentiate between irradiated and heat-treated samples.     

Effect of irradiation and germination on selected nutrients of corn

The effect of germination on potential nutrients (mineral matter, protein, lipids, fibre, carbohydrates and total energy) and an antinutrient (phytate) of corn, was studied. The influence of irradiation (5–20 krad) and germination on the vitamin contents (ascorbic acid, riboflavin) was also investigated. Comparison of the coefficients of variability revealed striking differences in the contents of these nutrients as a result of germination. Total mineral matter increased from 1·15% to 1·40%, protein from 9·6% to 14·0%, lipids from 4·36% to 4·60% and fibre from 0·71% to 0·82% whereas phytate decreased from 200 to $\text{105}\text{mg}\text{100}\text{g}$ and carbohydrates from 85·5% to 70·0%. Radiation and germination significantly affected the ascorbic acid and riboflavin contents of corn (p < 0.05). A maximum value of ascorbic acid ($\text{19·4}\text{mg}\text{100}\text{g}$) was observed in the 10 krad treated seeds as compared with $\text{14·3}\text{mg}\text{100}\text{g}$ in the control after 120 h of germination. Similarly, riboflavin increased from an initial value of 1·5 μg/g to 13·1 μg/g in the 20krad sample as compared with 6·0 μg/g in the unirradiated control.     

The irradiation of spices, packaging materials and luncheon meat to improve the storage life of the end products

Spices and packaging materials were exposed to γ‐irradiation at a dose of 10 kGy. Luncheon meat was prepared with irradiated or non‐irradiated spices and packaged in irradiated or non‐irradiated packaging materials. Packaged luncheon meat was treated with 2 kGy. Irradiated and non‐irradiated packaged luncheon meat were kept in a refrigerator (1–4 °C) for 12 months. Microbiological, nutritive and chemical characteristics of luncheon were evaluated after processing and during storage; whereas, sensory quality was evaluated only after irradiation. γ‐Irradiation decreased the microbiological counts of spices, packaging materials and packed products and increased its shelf‐life. No significant differences in moisture, protein, fat, pH value, total acidity, lipid peroxide and volatile basic nitrogen were observed as a result of irradiation. Sensory evaluation showed that all the combinations of treated luncheon meats were acceptable. However, the taste, odour, appearance and texture scores of irradiated packaged products were significantly lower than those of non‐irradiated samples.     

Methods for detection of irradiation of spices

European Food Research and Technology - Three types of methods for the identification of irradiation of spices were tested as potential control methods. The methods were microbiological, combining...     

Methods for detection of irradiation of spices

Three types of methods for the identification of irradiation of spices were tested as potential control methods. The methods were microbiological, combining a direct epifluorescent filter technique (DEFT) with a total aerobic plate count (APC), a chemiluminescence method and chemical gas-chromatographic (GC) and GC mass-spectrometric (MS) methods for analysis of volatile oils of spices isolated by steam distillation. Twelve samples of spices, mainly peppers, were analysed before and after gamma-irradiation with doses of 10 and 50 kGy. The chemiluminescence measurements were performed before the irradiation and 10 and 100 days after the irradiation. The best methods for control purposes were the microbiological (DEFT + APC) methods combined with chemiluminescence measurements. No differences were detected between the irradiated and non-irradiated samples with the chemical methods.     

Effect of gamma irradiation on the microbiological quality and antioxidant activity of fresh vegetable juice

A fresh vegetable juice has become a new functional food available for dieting and health. However, it poses a microbiological hazard to the consumer because it is distributed and consumed without any cooking. In this study, we applied the radiation sterilization of fresh vegetable juice, and the effectiveness of gamma irradiation for inactivating Salmonella typhimurium and Escherichia coli in the carrot and kale juice was investigated. D((10)) values of S. typhimurium in the carrot and kale juice were 0.445+/-0.004 and 0.441+/-0.006 kGy, while those of E. coli were 0.301+/-0.005 and 0.299+/-0.006 kGy. The test organisms (inoculated at 10(7) cfu/ml) were eliminated by irradiation at 3 kGy. The total phenol contents of the irradiated juice during 3 days of storage at a cold chain temperature (10 degrees C) increased significantly (P<0.05), while those of the non-irradiated juice decreased (P<0.05). The antioxidant capacity of the irradiated carrot juice was higher than that of the non-irradiated control. Therefore, it was concluded that irradiation treatments of carrot and kale juice improve the microbiological safety with maintaining or even enhancing the antioxidative activity.     

Effects of approved dose of e-beam irradiation on microbiological and physicochemical qualities of dried laver products and detection of their irradiation status

Food Science and Biotechnology - Most commercial dried laver products show higher microbial contamination. This work evaluated effects of approved dose (7&nbsp;kGy)—recommended in the...     

Effect of irradiation and chilled storage on the microbiological and sensory quality of a ready meal

The sensory and microbiological quality of both non-irradiated and irradiated cook-chill ready meals consisting of roast beef and gravy, cauliflower and sauce together with roast and mashed potatoes were assessed at intervals during 15 d storage at 2–3°C.
Growth of Pseudomonas spp. caused obvious spoilage of the non-irradiated meals after storage, whereas spoilage was not apparent in the irradiated meals. Irradiation (2 and 3 kGy) reduced the number of microorganisms in the meal to <100 g⁻¹ initially and significant microbial growth did not occur during storage.
Using sensory profiling techniques a trained panel found that the effects of irradiation and chilled storage were most apparent in the cauliflower and potato components and occurred most often in the colour, appearance and textural attributes.
The combination of low dose irradiation and chilled storage effectively controlled microbial growth but changes in the sensory characteristics may limit the potential of irradiation to extend the shelf-life and enhance the safety of this ready meal.     

Occurrence of aflatoxins in selected spices in Poland

The aim of this study was to determine the contamination of aflatoxins B₁, B₂, G₁, G₂ in some selected spices (n = 84) in the Kuyavian-Pomeranian province of Poland. Aflatoxins were found in 63.1 % of the analysed samples. The presence of these compounds was confirmed in all the samples of pepper, nutmeg and turmeric. The maximum content for the sum of aflatoxins B₁, B₂, G₁, G₁ exceeding the acceptable level (10 μg/kg) was 16.91 μg/kg in one sample of nutmeg and 12.1 μg/kg in one sample of pepper, whereas in one sample of nutmeg the maximum content was equal to the regulatory limit. The lowest degree of contamination was found in black pepper.     

Assessment of microbiological contamination in saengshik products from the Korean market and identification of the irradiation status

Food Science and Biotechnology - This study investigated the prevalence of microbiological contamination in commercial Saengshik products (samples SP-1 to SP-12) from the Korean market, and...     

Antioxidant activities of extracts from selected culinary herbs and spices

Recently, interest in plant-derived food additives has grown, mainly because synthetic antioxidants suffer from several drawbacks. Furthermore, plant extracts have been shown to possess health-promoting properties. In the present study, hydrodistilled extracts from basil, laurel, parsley, juniper, aniseed, fennel, cumin, cardamom, and ginger were assessed for their total phenol content, and antioxidant (iron(III) reduction, inhibition of linoleic acid peroxidation, iron(II) chelation, 1,1-diphenyl-2-picrylhydrazyl radical-scavenging and inhibition of hydroxyl radical-mediated 2-deoxy-d-ribose degradation, site and nonsite-specific) activities. The extracts from basil and laurel possessed the highest antioxidant activities except for iron chelation. Although parsley showed the best performance in the iron chelation assay, it was less effective at retarding the oxidation of linoleic acid. In the linoleic acid peroxidation assay, 1 g of the basil and laurel extracts were as effective as 177 and 212 mg of trolox, respectively. Thus, both extracts are promising alternatives to synthetic substances as food ingredients with antioxidant activity.     

Screening of selected Asian spices for anti obesity-related bioactivities

The potential health effects of 30 spices, commonly used for daily consumption, were submitted to bioactivity screening with several anti-obesity related bioassays: adenosine A1 receptor binding, cannabinoid CB1 receptor binding, TNF-α and 3T3-L1 adipocytes differentiation induction. Sesame seed and red chilli exhibited high binding activity to the adenosine A1 receptor and nutmeg, mace, black pepper and turmeric to the cannabinoid CB1 receptor, while piment and turmeric showed high inhibition of TNF-α accumulation. Black onion seed proved to be the only spice with high 3T3-L1 adipocyte differentiation induction activity. Several well known major compounds found in these active spices were tested with the respective bioassays but did not show activity. Thus, it appears that other minor compounds or the synergistic effects of different constituents are responsible for the observed activity.     

Inhibitory effects of selected Turkish spices and oregano components on some foodborne fungi

The inhibitory effects of 10 selected Turkish spices, oregano essential oil, thymol and carvacrol towards growth of 9 foodborne fungi were investigated in culture media with pH 3.5 and 5.5. The antifungal effects of sodium chloride, sorbic acid and sodium benzoate and the combined use of oregano with sodium chloride were also tested under the same conditions for comparison. Of the spices tested, only sodium chloride were also tested under the same conditions for comparison. Of the spices tested, only oregano at 1.0, 1.5, 2.0% (w/v) levels showed effect on all fungi. 8% (w/v) sodium chloride was less effective than oregano. Oregano essential oil, thymol or carvacrol at concentrations of 0.025% and 0.05% completely inhibited the growth of all fungi, showing greater inhibition than sorbic acid at the same concentrations. The combined use of oregano and sodium chloride exhibited a synergistic antifungal effect.     

电子束辐照对三种香辛料的杀菌效果及香气成分的影响

研究了电子束辐照对八角、桂皮、花椒三种香辛料的杀菌效果及对其色泽、香气成分的影响,实验结果表明:0~15 k Gy剂量的电子束辐照对三种香辛料均有良好的杀菌效果,能延长香辛料的保鲜期,且不影响香辛料的色泽及口感,综合顶空固相微萃取及气质联用技术测定其香气成分实验结果,确定八角、桂皮、花椒辐照杀菌的适宜剂量分别为6、6、9 k Gy。      

Effect of low‐dose irradiation on shelf life and microbiological safety of sliced carrot

Minimally processed non‐irradiated carrots (sliced) exhibited diverse microflora at initial level. During storage, bacterial number increased with the presence of pathogenic bacteria accompanied by a loss of total solids. On the other hand γ‐irradiation at an optimal dose of 2 kGy offered a pathogen‐free, hygienic product with insignificant losses in nutrients such as in sucrose, total carotenes and ascorbic acid content in comparison to controls and 2‐ to 4‐fold increased in shelf‐life at refrigeration temperature. The D₁₀ values of pathogens like Escherichia coli and Yersinia enterocolitica in carrot paste were in a lower range (0.12–0.26 kGy) compared with that of Listeria monocytogenes (0.3–0.5 kGy). The validity of the processing treatment (2 kGy) was challenged by artificially inoculating Listeria monocytogenes in the product. Thus, minimally processed carrots (sliced) are amenable to radiation treatment for extended storage stability and microbial safety. Copyright © 2005 Society of Chemical Industry     

Identification of phenolic components in dried spices and influence of irradiation

LC–ESI-MS analysis was used for identification of phenolic compounds in the methanolic extracts of commercially available dried oregano, sage and thyme. Rosmarinic acid, apigenin-glucuronide, luteolin-glucuronide, as well as quinic acid were present in all three spices. Whereas in thyme and sage only derivatives from flavonoid compounds were identified, in oregano also the aglycons eriodictyol, naringenin, hispidulin, apigenin and luteolin could be found. Some constituents, especially glucosides and glucuronides, were observed for the first time in the methanol extracts of these spices. To ascertain an irradiation influence (dose: 10 kGy) the MS peak area counts of twenty constituents, among them 10 glycosides/glucuronides, were compared. Although the majority of those compounds exhibited a slight decrease with irradiation, the changes were not significant.     

不同天然香料物质对蜂蜜酒发酵及品质的影响

对蜂蜜酒的发酵醪中添加不同的天然香料进行了研究。初步建立了生产天然香料蜂蜜酒的工艺流程，对各种成酒进行了理化指标的分析，结果表明：添加天然香料后，与对照相比蜂蜜酒的发酵速度有较明显的提高，终产品中的酒精度增加、残糖量减少，其中以添加贡菊和玫瑰的发酵表现改善得最为明显，添加香料成分还提高了蜂蜜酒的品质，使香气和口感更加宜人。