Evaluation of diatomaceous earth formulations enhanced with natural products against stored product insects

The insecticidal effect of prepared insecticide formulations labelled as Natural P, Inert Natural P and Py EC on Sitophilus oryzae, Rhyzopertha dominica and Tribolium castaneum have been evaluated on wheat grains. Formulation Natural P contains diatomaceous earth (DE), amorphous silica gel (3%), pyrethrin, flax oil, lavandin essential oil (EO) and un-activated yeast. Formulation Inert Natural P contains DE, amorphous silica gel, lavandin EO and food grade bait whereas formulation Py EC contains pyrethrin, piperonyl butoxide (PBO), flax oil, polysorbate, methyl oleate and amorphous silica gel (5%). Celatom® MN-51 (diatomaceous earth – DE) was used as a standard insecticide. Inert Natural P and Natural P were applied as dust at four different doses and Py EC was applied as emulsions on grain by spraying. All three formulations showed higher insecticidal efficacy and higher progeny inhibition on all three tested insect species and had lower impact on wheat bulk density reduction compared with Celatom® MN-51. The LD₅₀ and LD₉₀ values of Inert Natural P were 48.7 and 163.7 ppm respectively for S. oryzae, 15.2 and 178.0 ppm for R. dominica and 115.2 and 171.3 ppm for T. castaneum. The LD₅₀ and LD₉₀ values of Natural P were 83.6 and 97.9 ppm respectively for S. oryzae, 19.5 and 97.9 ppm for R. dominica and 75.4 and 105.6 ppm for T. castaneum. Applied Py EC at concentration of 2.0 ppm a.i. pyrethrin exhibited 100% mortality after 2 d of S. oryzae and T. castaneum and after 6 d of R. dominica. In addition, all three formulations caused significant reduction of progeny (F1) population compared to control, providing promising approach of integrated pest management strategy.     

Field trials on the efficacy of Beauveria bassiana,diatomaceous earth and Imidacloprid for the protection of wheat grains from four major stored grain insect pests

We assessed the insecticidal efficacy of Beauveria bassiana, diatomaceous earth (DE) and the neonicotinoid Imidacloprid against four major insect species of stored grain pests during field trials conducted on small farms located in four districts of Punjab, Pakistan. In each district, a 40 kg lot of wheat grain was admixed with B. bassiana (3 × 10¹⁰ conidia kg⁻¹), DE (150 ppm) and Imidacloprid (5.0 ppm) alone and in different combinations. Each lot was divided subsequently into four equal parts (10 kg each), packed in polypropylene bags, artificially infested, labeled and stored at the farms under natural environmental conditions up to 6 months. Sampling was carried out every 30 d to record the total number of dead and alive adults, as well as the percent of grain damage in treated and untreated (control) grains. Results revealed a significant difference among the treatments, test insect species and the storage period. For each district, the combined treatments provided better control of all tested insect species compared with each treatment alone. The least number of surviving adults and minimum percent grain damage was observed for Imidacloprid and DE combination, but was outperformed by the DE treatment with B. bassiana for long-term protection. For all grain protectants, we obtained the same order of susceptibility level among the test species (i.e. Liposcelis paeta > Cryptolestes ferrugineus > Rhyzopertha dominica > Tribolium castaneum). The results of the present study suggested that DE, insect pathogenic fungi and Imidacloprid can be effectively used for the protection of wheat stored at small-scale farmer's fields.     

食物及挥发物对米象、玉米象及锯谷盗诱集效果的研究

针对为减少粮食损失、减少熏蒸剂的用量,而运用食物引诱剂对仓虫监控和防治这一重要课题,本研究在实验室条件下测试2种食物和4种食物中对害虫有引诱作用的有效化学成分单一或组合时对3种害虫的诱集效果,从而筛选出对每种实验昆虫诱集效果最佳的诱集物配比方案。试验表明,对米象诱集效果最好的组合为香草醛(0.012 g)+二氯甲烷(0.5 m L)+亚油酸(2.5 m L)+二十烷(0.02 g),诱集率最高可以达到65.2%;对玉米象诱集效果最好的为单一米糠,诱集率可达74%;对锯谷盗诱集效果最好的是单一的诱集物香草醛,诱集率最高可以达到64%以上。     

Effectiveness of diatomaceous earth for control of Sitophilus zeamais (Coleoptera: Curculionidae), Tribolium castaneum and Palorus subdepressus (Coleoptera: Tenebrionidae)

The effectiveness of diatomaceous earth (DE) or diatomite has been assessed against three major beetle pests of stored maize: Sitophilus zeamais (the maize weevil), Tribolium castaneum (the red flour beetle) and Palorus subdepressus (the depressed flour beetle). Maize has been treated with four doses of DE (1.5, 3, 4.5 and 6 g/kg) and four doses of Actellic Super™ Dust a chemical insecticide used as a reference (0.25, 0.5, 0.75 and 1 g/kg). The effective mortality was measured for each treatment after 1, 2, 4, 7 and 14 d of exposure. The corrected mortality rates were calculated by considering the mortality in the control group. Diatomaceous earth was as effective as Actellic Super™ Dust but required higher doses. Diatomaceous earth acted faster on S. zeamais and P. subdepressus compared to T. castaneum. The highest dose tested for DE caused the same mortality in T. castaneum as the recommended dose of Actellic Super™ Dust. Diatomaceous earth is a good alternative for the control of these three devastating insect pests of maize stocks and can readily be incorporated into integrated stored products pest management programs.     

Effectiveness of spinosad combined with diatomaceous earth against different European strains of Tribolium confusum du Val (Coleoptera: Tenebrionidae): Influence of commodity and temperature

Laboratory bioassays were carried out to assess the effects of combining spinosad at 0.01, 0.1 and 0.5 ppm, with the diatomaceous earth (DE) formulation SilicoSec at rates of 150, 300 and 600 ppm, against larvae and adults of three different populations of Tribolium confusum du Val (Coleoptera: Tenebrionidae), originating from different European countries (Greece, Portugal and Denmark). Tests were conducted on wheat and maize at 25 and 30 °C. Survival of T. confusum larvae was assessed after 7 d exposure and survival of adults was assessed after 7 d and 14 d of exposure. At each dose of spinosad, survival of T. confusum individuals decreased as the rate of DE increased. As temperature increased, the efficacy of spinosad and Silicosec applied either alone or in combination also increased. The efficacy of spinosad alone was slightly higher on maize than wheat, while the reverse was noted for all the tested combinations of spinosad with DE as well as in the case of the application of DE alone. The strain from Portugal was always the least susceptible of the three tested. Our study indicates that it is possible to combine low doses of DE (<600 ppm) with spinosad (<1 ppm) to control adults and larvae of T. confusum, especially at temperatures >25 °C.     

Influence of temperature and application rate on efficacy of a diatomaceous earth formulation against Tribolium castaneum adults

Unsanitary storage bins can harbor grain-infesting insects, including the red flour beetle, Tribolium castaneum (Herbst). In a previous study involving heat treatment of empty bins, temperatures in the range of 50–55 °C for 2–4 h were effective in completely killing stored-product insects. Previous research in flour mills showed improved efficacy in killing stored-product insects by using diatomaceous earth (DE) dusts at temperatures below 50 °C. In the current study, the efficacy of a diatomaceous earth formulation (DiaFil^® 610) applied to concrete arenas, to simulate floor of empty bins, was examined at three application rates (0, 2.5 and 5.0 g/m²) to control T. castaneum adults at five constant temperatures (28, 36, 42, 44, and 46 °C). Ten adults of T. castaneum were placed on individual untreated and DE-treated concrete arenas for 4, 8, 12, and 24 h at each of the five temperatures. The efficacy of DE against T. castaneum adults increased with an increase in temperature and exposure time. Generally more adults died at 5.0 g/m² when compared with 2.5 g/m². In 2.5 and 5.0 g/m² DE treatments, exposure for 12 h at a temperature of 42 °C resulted in 73–77% mortality of adults with 100% mortality observed after 24 h. At 44 and 46 °C, 100% mortality of adults was observed after 24 h of exposure at both DE rates. At these two temperatures, the high mortality in untreated arenas (controls) at 8, 12, and 24 h exposures ranged from 27 to 100% confounding the true effects of DE. Our results suggest that combined use of DE and temperatures below 50 °C can be used as an integrated approach for controlling insects in empty bins prior to storage of newly-harvested grain.     

Stored grain pest prevalence and insecticide resistance in Egyptian populations of the red flour beetle Tribolium castaneum (Herbst) and the rice weevil Sitophilus oryzae (L.)

As a consequence of the widespread use of insecticides against insect pests in grain warehouses and in the food industry, insecticide resistance has greatly increased among these species all over the world. Nonetheless, insecticide resistance in stored grain insects in Egypt was little studied. Therefore, our study aimed to forecast infestation risks and determine the insecticide resistance level in Egyptian populations of the main insect pests of stored grains. To achieve this goal, we surveyed the populations of stored-product insects in wheat in two different sites in the Alexandria governorate (Egypt) between June and August 2017. Moreover, insecticide resistance levels in Egyptian populations of Tribolium castaneum (Herbst) and Sitophilus oryzae (L.) collected from wheat storage facilities (granaries and flour mills) in Alexandria governorate were also determined. Three contact insecticides, namely malathion, pirimiphos-methyl and cypermethrin, were tested. Tarsal contact bioassays on filter paper were carried out on adults following FAO methods and concentration-mortality lines were estimated to determine the resistance ratios for each insecticide and population. The data from the monitoring of insects revealed that T. castaneum and S. oryzae were the most common species infesting wheat in both Alexandria granaries and mills. Populations of S. oryzae were generally more resistant to malathion than the populations of T. castaneum. However, T. castaneum populations were more resistant to pirimiphos-methyl than the S. oryzae populations. Both populations of T. castaneum and S. oryzae were susceptible to cypermethrin. The detected levels of insecticide resistance indicate that this phenomenon takes place and should be a concern in Egyptian populations of T. castaneum and S. oryzae requiring monitoring and design of resistance management practices.     

Residual efficacy of an insecticide-coated net for the control of stored product beetles

In the present study, the residual efficacy of an alpha-cypermethrin-coated net (Carifend®, BASF AG, Ludwigshafen, Germany) was evaluated in laboratory studies against four species of stored product insects. The insecticide-treated net was fitted into the bottom of plastic petri dishes, whereas two other sets of dishes (without net, with net without insecticide) served as controls. The insects used in the bioassays were Sitophilus oryzae, Tribolium confusum, Oryzaephilus surinamensis and Prostephanus truncatus. Adults of these species were exposed every 30 d for a total of 90 consecutive days in total. Based on the results, the insecticidal effect of the net remained at high levels during the entire experimental period, indicating its high residual effect. Among the species tested, T. confusum was the least susceptible. Carifend® can be a valuable tool for the protection of stored products against storage insects, and its use can be further examined towards this direction.     

Effects of spinosad on the heat tolerance and cold tolerance of Sitophilus oryzae L. (Coleoptera: Curculionidae) and Rhyzopertha dominica F. (Coleoptera: Bostrichidae)

Sitophilus oryzae and Rhyzopertha dominica are serious insect pests of stored products in Sri Lanka. Currently pirimiphos methyl and phosphine fumigation are used as control measures but grain handlers seek for alternatives. Exposure to high or low temperature is popular in stored-product insect pest management but is expensive. Spinosad is effective against certain stored-product insects but has not yet been tested for its synergy with heat or cold. This experiment was conducted to evaluate the effect of spinosad on the heat tolerance and cold tolerance of S. oryzae and R. dominica adults. The experiment was a two-factor factorial, complete randomized design with four replicates. The spinosad concentration and exposure period were changed. Adults of S. oryzae and R. dominica were first exposed to a series of spinosad concentrations. Later they were held at higher (40 °C) or lower (6–11 °C) temperatures than room temperature for different durations.Pre exposure of S. oryzae adults to Spinosad at 18 ppm or above synergized the adult mortality at high or low temperature showing a dose response. Pre-exposure of R. dominica adults to spinosad concentrations 12.5 ppm or higher synergized the mortality at high temperature whereas the spinosad synergized the mortality of R. dominica at low temperature when exposed to 6.25 ppm or higher concentrations; the effects followed a dose response. This study shows that heat and cold tolerance of S. oryzae and R. dominica adults are reduced by pre-exposure to spinosad. Therefore, spinosad is a potential grain protectant at high or low temperatures against these two insect species.     

Gone with the weed: Population growth of Sitophilus oryzae and Rhyzopertha dominica in wheat and barley containing seeds of Silybum marianum

In the present study we examined the effect of seeds of the weed Silybum marianum (L.) Gaertn. (Asterales: Asteraceae) in different combinations with wheat or barley in the population growth of two major stored product insects, Rhyzopertha dominica (F.) (Coleoptera: Bostryhidae) and Sitophilus oryzae (L.) (Coleoptera: Curculionidae). The evaluation took place on 7 different quantitative combinations of the weed, i.e. 0, 1, 5, 10, 20, 50 and 100% of the total amount of the grain mass. All combinations were kept under constant conditions of 25 ^οC and 65% relative humidity (r.h.) for 65 days. After this interval, adult progeny production was counted, and classified as dead or alive. In general, progeny production was higher on wheat than on barley for R. dominica, but the reverse was recorded for S. oryzae. No progeny production was recorded for either species when S. marianum containment was 100%. Moreover, for both species, the decrease of the percentage of S. marianum caused an increase in progeny production, but this decrease was not linear. The study concludes that R. dominica and S. oryzae cannot develop on S. marianum seeds, but they can develop in mixtures of these seeds with grains.     

Degradation and residual efficacy of beta-cyfluthrin as a surface treatment for control of Tribolium castaneum Herbst: Effects of temperature and environment

Concrete arenas were treated with the low and high label rates of beta-cyfluthrin Tempo SC Ultra® (10 and 20 mg Active Ingredient [AI]/m², respectively) and stored during the summer and autumn in two separate years inside an empty grain bin, inside a rice mill, and inside a laboratory at an approximate ambient temperature of 27 °C. Bioassays were conducted by removing the arenas at 0 (1 day) to 10 weeks post-treatment from the three locations where they were stored, and exposing adults of Tribolium castaneum (Herbst), the red flour beetle, for 0.5–3 h on the arenas. Rapidity of knockdown was used to assess residual efficacy. Application rate was significant (P < 0.05) for rapidity of knockdown for the summer storage period but not for autumn (P ≥ 0.05). As the weeks progressed during summer, knockdown was progressively slower during the 0.5 to 3-h exposure period on arenas held inside the grain bin compared to the arenas inside the rice mill and the laboratory. During autumn the order was reversed for the grain bin and laboratory as the weeks progressed but at 10 weeks knockdown after 3 h was still much less on arenas held inside the bin and mill compared to the laboratory. Extreme high temperatures in the grain bin during the summer, and the fluctuating temperatures during autumn, may have promoted residual degradation on arenas held in the bin and mill compared to the constant temperatures in the laboratory. Results show that residual persistence of contact insecticides for control of stored product insects may be less on treated surfaces outside of a laboratory setting, and caution is warranted when predicting time periods for residual efficacy in sites that are outside of research laboratories with stable environmental conditions.     

Efficacy of alpha-cypermethrin,chlorfenapyr and pirimiphos-methyl applied on polypropylene bags for the control of Prostephanus truncatus (Horn), Rhyzopertha dominica (F.) and Sitophilus oryzae (L.)

We examined the immediate and delayed mortality of adults of the larger grain borer, Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae), the lesser grain borer, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) and the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) on surfaces of polypropylene storage bags under different treatment scenarios with alpha-cypermethrin, chlorfenapyr and pirimiphos-methyl. These scenarios were: only one surface of the bag was sprayed and insects were exposed on sprayed or unsprayed surface or both surfaces were sprayed. We evaluated the immediate mortality for 1, 3 and 5 days (d) of exposure. Then, we transferred the surviving adults to untreated surfaces of the same type of storage bags and measured the delayed mortality after 7 d of exposure. We also evaluated the effect of insecticidal treatments on the numbers of holes/bites made by the activity of P. truncatus and R. dominica on storage bags. In terms of immediate mortality, chlorfenapyr and pirimiphos-methyl were very effective against all three species and alpha-cypermethrin against P. truncatus. We noticed high mortality values of all species to chlorfenapyr and pirimiphos-methyl, even after 3 d of exposure, reaching 100% in many of the cases examined. For the majority of exposure intervals, insecticides and insects, we did not find significant differences in mortality counts between exposures on sprayed surfaces of the bag. Immediate mortalities of insects exposed on the untreated surface of the bag did not differ significantly with mortalities at the surface single treated with alpha-cypermethrin and pirimiphos-methyl. Concerning delayed mortality, all S. oryzae adults were found dead 7 d after their transfer to untreated bags irrespectively of the treatment. The delayed mortality of P. truncatus and R. dominica adults was either complete (after exposure to chlorfenapyr) or almost complete (after exposure to alpha-cypermethrin). The exposure of P. truncatus and R. dominica to alpha-cypermethrin almost completely suppressed the numbers of holes/bites. Our study indicates that the application of insecticides on polypropylene storage bags can be considered as an effective method for the control of stored-product insects.     

Efficacy of ozone for Callosobruchus maculatus and Callosobruchus chinensis control in cowpea seeds and its impact on seed quality

The insecticidal efficacy of ozone was evaluated against the adults of Callosobruchus maculatus (F.) and C. chinensis L. on stored cowpea seeds under laboratory conditions. Ozone was assessed at concentrations of 0.25, 0.5, 1.0, 1.5, and 2.0 g/m³. The effect of ozone treatments on the adult mortality after 1, 3, 5 and 7 days of treatment, progeny production after 45 days, cowpea seed weight loss, seed germination and chemical constituents of cowpea seeds were determined. Adult mortality of C. maculatus and C. chinensis was improved with the increase in ozone concentration. Thus, all tested concentrations caused complete adult mortality of C. chinensis after 7 days of treatment, while the concentrations of 1.0, 1.5, and 2.0 g/m³ caused complete adult mortality of C. maculatus after the same periods. Progeny of both species was significantly decreased in all ozone concentrations after 45 days of treatment. Nevertheless, strong suppression in progeny production was achieved at the highest concentration of ozone (2.0 g/m³). Also, the ozone treatment at the highest concentration protected the cowpea seeds from damage caused by C. maculatus and C. chinensis for 45 days. In addition, there was no significant effect of ozone treatments on the cowpea seed germination compared with untreated seeds. Moreover, the chemical analysis of treated cowpea seeds showed a slight decrease in protein, fat, carbohydrate, moisture, total phenolics, total flavonoids and tannins contents, and a slight increase in fiber and ash contents compared with untreated cowpea seeds. Our findings suggest the ozone can be effectively used for the control C. maculatus and C. chinensis and can provide sufficient protection of stored cowpea seeds.     

Insecticidal efficacy of diatomaceous earth against Sitophilus oryzae (L.) (Coleoptera: Curculionidae) and Tribolium confusum du Val (Coleoptera: Tenebrionidae) on stored wheat: influence of dose rate, temperature and exposure interval

Laboratory experiments were conducted in order to assess the insecticidal effect of a diatomaceous earth formulation (Silicosec^®, Biofa GmbH, Germany) against Sitophilus oryzae and Tribolium confusum on stored wheat. Adults of the two species were exposed on wheat treated with diatomaceous earth at four dose rates: 0.25, 0.5, 1 and 1.5 g/kg of wheat, respectively. For each dose rate, the treated wheat was placed at 22°C, 25°C, 27°C, 30°C and 32°C. Dead adults were counted after 24 and 48 h, 7 and 14 d of exposure. After the 14-d interval, the live adults were removed and placed for 7 d in untreated wheat (in the case of S. oryzae) or untreated flour (in the case of T. confusum), and the production of F₁ was recorded. For both species, dose rate, temperature and exposure interval significantly affected mortality (P<0.001). Mortality was higher at longer exposure intervals. The efficacy of SilicoSec against S. oryzae increased with temperature, but for T. confusum mortality was lower at 32°C, compared to 30°C, for 24 and 48 h exposure intervals. Tribolium confusum proved less susceptible to SilicoSec than S. oryzae. In general, the rates of 1 and 1.5 g/kg of wheat provided a satisfactory level of protection against the two species examined. For S. oryzae, F₁ emerged only at 22°C, in wheat treated with 0.25 or 0.5 g/kg. However, for T. confusum, F₁ were recorded at 22°C for 0.5 g/kg and at 22°C, 25°C, 27°C and 30°C for 0.25 g/kg.     

粮食重金属快速检测产品性能评价与分析

通过对10个不同品牌的粮食重金属快速检测产品进行适用性评价研究,了解市面上主要重金属快速检测产品的准确度、精密度及实际应用性能,采用“三三七”原则,分别对大米中铅镉元素进行了统计学分析。结果表明,10个品牌的粮食重金属快速检测产品对大米中镉元素的回收率基本满意,测定结果与样品标准值无显著性差异（P＞0.5）,而大米中铅元素检测不同品牌质量不一,部分品牌测定结果与样品标准值存在显著性差异（P＜0.5）,其中1个品牌数据离群,判定为不合格。10个品牌中有3个品牌产品稳定性较差,受人员操作影响较大。10个品牌均可在40 min内完成一个批次检测,检测时间短,操作简单,价格合理。综合评价指标显示目前市面上主要的粮食重金属快速检测产品仍存在一定的性能差异,需要改进。     

Enhancement of antimicrobial and antimutagenic activities of Korean barberry (Berberis koreana Palib.) by the combined process of high‐pressure extraction with probiotic fermentation

BACKGROUND: To evaluate the combined effects of high pressure extraction (HPE) and probiotic fermentation on the antimicrobial and antimutagenic activities, Berberis koreana was subjected to 500 MPa for 30 min and then fermented with Bifidobacterium longum B6 (HPE‐BLF) and Lactobacillus paracasei (HPE‐LPF) at 37 °C for 6 days. RESULTS: The phenol content was significantly increased to 228 mg GAE g^?1 by the HPE compared to the conventional extraction (CE, 188 mg GAE g^?1). The HPE‐BLF and HPE‐LPF showed the highest antimicrobial activity (MIC < 4 mg mL^?1) against β‐lactam antibiotic sensitive and resistant Staphylococcus aureus. No significant mutagenic effect was observed for CE, HPE, HPE‐BLF, and HPE‐LPF extracts. The highest antimutagenic activities against frame‐shift mutant Salmonella typhimurium were observed at the HPE‐LPF (82%), followed by the HPE‐BLF (77%). CONCLUSION: The combined HPE and fermentation process could be used as an alternative extraction method for improving the extraction efficacy of medicinal plants. The results will provide pharmaceutically useful information and potential direction for finding new drug sources from medicinal plants. Copyright © 2010 Society of Chemical Industry     

Environmental factors affect efficacy of some essential oils and resveratrol to control growth and ochratoxin A production by Penicillium verrucosum and Aspergillus westerdijkiae on wheat grain

This study determined the efficacy of three essential oils (bay, clove and cinnamon oil) and the antioxidant resveratrol (0–500 μg g⁻¹) on the control of growth and ochratoxin A (OTA) production by Penicillium verrucosum and Aspergillus westerdijkiae (=A. ochraceus) under different water activity (a_w, 0.90, 0.95, 0.995), and temperature (15, 25 °C) conditions on irradiated wheat grain. The most effective treatment (resveratrol) was then tested on natural grain. The ED₅₀ values for growth inhibition by the oils were 200–300 μg g⁻¹ at the a_w and the temperatures tested. For resveratrol, this varied from <50 μg g⁻¹ at 0.90–0.95 a_w to >350 at 0.995a_w at both temperatures. The ED₅₀ values for the control of OTA were slightly lower than for control of growth, with approx. 200 μg g⁻¹ required for the oils and 50–100 μg g⁻¹ of the antioxidant, at 0.90/0.95a_w and both temperatures. In wet grain (0.995a_w), higher concentrations were required. For growth there were statistically significant effects of single-, two- and three-way interactions between treatments except for concentration×temperature and concentration×temperature×essential oil/antioxidant treatment. For OTA control, statistically significant treatments were a_w, temperature×a_w, concentration×temperature, treatment×concentration, and three-way interaction of concentration×a_w×treatment for P. verrucosum and A. westerdijkiae. Subsequent studies were done with the best treatment (resveratrol, 200 μg g⁻¹) on natural wheat grain with either P. verrucosum or A. westerdijkiae at 0.85–0.995a_w and 15/25 °C over 28 days storage. This showed that the populations of the mycotoxigenic species and OTA contamination could be reduced by >60% by this treatment at the end of the storage period.     

近红外光谱技术结合化学计量学用于畜禽肉制品品质分析的研究进展

肉类作为人体摄入蛋白质的主要来源,随着人们生活水平的提高和对营养健康的追求,肉制品的需求量不断增大,与此同时,肉制品新鲜度、掺杂掺假等肉制品品质领域的质量问题较为多发。为改善传统肉类检测方法耗时费力的现状,肉品质量的检测方法也逐渐趋于多样化。近红外光谱技术目前已广泛应用于包括生物、医药、食品在内的诸多领域。近红外光谱技术与化学计量法结合可对样品进行定性和定量分析,具有快速、无损、高效的优势,适用于肉品及肉制品现场实时监测。在前期研究的基础上,本文综述了近年来近红外光谱技术在畜禽肉制品新鲜度、品种鉴别与掺假分析、产地溯源等方面的研究进展,以期为肉制品品质分析及质量控制提供理论指导。     

Reduction of nectarine decay caused by Rhizopus stolonifer, Botrytis cinerea and Penicillium digitatum with Aloe vera gel alone or with the addition of thymol

Two nectarine cultivars (‘Flavela’ and ‘Flanoba’) were treated with Aloe vera gel alone, or with the addition of thymol, and then inoculated with Rhizopus stolonifer, Botrytis cinerea and Penicillium digitatum. Both treatments were effective in reducing the decay incidence caused by the 3 fungi species, although the addition of thymol did not generally improve the efficacy of Aloe vera gel on reducing the infection damage. The coatings were clearly effective in reducing the postharvest ripening process of both nectarine cultivars manifested by a delay in ethylene production and respiration rate, weight loss and softening. Interestingly, these coatings showed effectiveness on reducing decay development in inoculated fruits and thus Aloe vera could be considered as natural antifungal compound and might serve as alternative of synthetic fungicides.