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991.
While food insecurity is a growing concern across the developing nations, accentuated by climate variability and change, it could be even worse for pastoralists given their unpredictable exposure to climate risks. The Borana herders experience food insecurity as a result of recurring droughts causing huge losses of cattle, and are thus increasingly shifting from cattle pastoralism to multi-species herding. The present study examines the role of livestock diversification in combating household food insecurity using herders’ perceptions, a modified household food insecurity access scale (mHFIAS) and dietary diversity score. Herders perceived child growth, adult height and body condition to be decreasing as a result of declining milk production and changing dietary trends. Results also revealed a high level of seasonal food insecurity and low dietary diversity with the majority (81 %) consuming one to three food groups. Livestock diversification was a major factor affecting household food security. Households practising diversification had significantly fewer months of food deficit (2.3 vs. 3.8), lower mHFIAS (5.5 vs. 8.7) and a higher average off-take in the form of livestock sales (7.4 vs. 4.0) than non-diversified ones. Diversification improved dietary intake of specific food groups and the average number of meals consumed per day. While fruits, eggs and fish are not part of the Borana diet, a large number of respondents consumed no vegetables (93 %) or meat (96 %), potentiating the risk of micronutrient deficiencies. This study highlights the particular significance of livestock diversification, among other socio-demographic factors, in attaining food security under a changing climate in the study area.  相似文献   
992.
The effects of pulsed electric field (PEF) processing on microorganisms in orange juice and on the flavor and color of the juice during storage for 112 days at 4 and 22 degrees C were investigated. Single-strength orange juice was PEF processed at an electric field strength of 35 kV/cm for 59 micros and placed into sterilized glass bottles in a sanitary glove box. PEF-processed orange juice was microbiologically stable at 4 and 22 degrees C for 112 days. PEF processing resulted in significant increases in the hydrocarbons D-limonene, alpha-pinene, myrecene, and valencene (P < or = 0.05) but did not have any effect on octanal, decanal, ethyl butyrate, and linalool. The levels of hydrocarbon compounds did not change at 4 and 22 degrees C in 112 days. Octanal, decanal, ethyl butyrate, and linalool levels significantly decreased in 14 days at 4 degrees C and in 2 days at 22 degrees C. The decrease in these compounds did not have a significant effect on the sensory quality of the orange juice (P > or = 0.05). The microorganisms in PEF-processed orange juice, along with the flavor and color of the juice, remained stable at 4 degrees C for 112 days.  相似文献   
993.
In checking harvesting discipline and quality control for oil palm fruits, color has presumably been an important guide to whether the oil content has reached a maximum where the fruit bunch is ready for cutting. However, establishing a single and harmonious standard base on color is a very contentious issue in the oil palm industry because of the subjective nature of the human vision of color. This was further complicated due to the lack of information on fruit color upon which to base a definite ripeness criterion. We demonstrated in this paper that this problem can be solved using machine vision technology. Methods used were to treat color in HSI (Hue, Saturation and Intensity) color space and applied multivariate discriminant analysis. These have proven to be highly effective for color evaluation and image processing. The vision system was trained to classify oil palms into four quality grades according to PORIM (Palm Oil Research Institute of Malaysia) inspection standards. These are the unripe, the underripe, the optimally ripe and the overripe classes. Depending upon the quality feature evaluated, misclassification by the vision system varied from 5 to 12% but averaged at about 8%. Machine vision disagreement ranged from 2 to 19%.  相似文献   
994.
Three techniques of gas chromatography (GC) either with flame photometric-detector (FPD), electron capture detector (ECD), or with mass-spectrometry (MS) were applied for identification and quantification of pesticide residues on 45 samples of cucumber, tomatoes, and strawberries in fifteen locations in Gaza Governorates. GC-FPD analysis showed the presence of four different organo-phosphorus (OP) pesticides, their levels were very low and below maximum residue limits (MRL's). GC-ECD detected ten different pesticides at levels below the MRL's. Using the GC-MS technique, alpha and beta-endosulfan, chlorpyrifos, carbofuran, chlorfluazuron, triadimenol I and II, penconazole, coptafolmetabolite, pyrimethanil and iprodione were detected and confirmed on some samples of cucumber, tomatoes and strawberries. All GC-MS pesticide residues detected on tomato were below the MRL's except chlorfluazuron while on strawberry were below the MRL's except penconazole, chlorfluazuron and pyrimethanil, but on cucumber were slightly higher than the MRL's except alpha and beta-endosulfan. Also, statistical analysis of pesticide residues in all samples showed that most of the detected residues mean were significantly lower than the MRL's (p < 0.05). Generally, tomatoes showed the least number and level of pesticide residues by all the GC-techniques. On the other hand, strawberries showed greater number and levels of pesticide residues, particularly by the GC-MS technique. These results indicate that the protective period to elapse before harvesting should be increased especially on strawberry. The results also can help in risk assessment of consumers exposure to the expected pesticide residues.  相似文献   
995.
蒸发器结晶垢的螺旋纽带自动清洗技术的结构原理,是直接利用蒸发溶液的循环流动带动加热管内的螺旋纽带旋转清洗.根据结晶动力学原理,采用碳钢管25×2.5×1820内用Na2SO4、KClO3的冷却过饱和溶液的结晶盐垢进行流体动力学模拟试验研究.结果表明,能够满足一般生产蒸发器的自动清洗要求,达到长期连续生产的目的,并且设备成本费用低,具有显著的技术经济优势,可以在制糖、制盐、烧碱、化工、食品、制药等工业生产部门广泛应用.  相似文献   
996.
该文对喀麦隆传统Bili啤酒的酿造过程及其主要化学组成进行了分析和调查研究。并从各地Bili啤酒酒样中分离酵母菌 3 1株。根据各酵母菌株的生物学特性对其进行了分类与鉴定。发现这些酵母菌分属于Saccharomyces ,Candida ,Kluyveromyces和Pichia等四个属 ,其中以Saccharomyces属的酵母菌为参与喀麦隆Bili啤酒酿造的主要酵母菌种。  相似文献   
997.
Total polyphenols, carotenoids and vitamin C were assessed in three different peaches cultivars (Prunus persica): ‘Luisa Berselli’ (LB), ‘Stark Earlyglo’ (SE) and ‘Maria Serena’ (MS). Total antioxidant capacity of fruits and plasma antioxidant activity after ingestion of fruits were determined as Trolox equivalent antioxidant capacity (TEAC) and as plasma total radical-trapping potential (TRAP) respectively. The amount of polyphenols, carotenoids and vitamin C resulted to be generally similar in the three cultivars. TEAC, measured from harvest to 7 days postharvest, resulted to be influenced mainly by vitamin C content, whereas polyphenols and carotenoids seemed to play a secondary role. Although TEAC was similar in the three cultivars, only LB significantly increased the TRAP in human plasma at 1, 2 and 4 h after ingestion of peaches. Sugar moiety, condensed and glycoside phenols are suggested to be involved in the higher effect on plasma TRAP of LB.  相似文献   
998.
Friesian cattle, aged 26-27 months, were fed a diet supplemented with 2000IU α-tocopheryl acetate/kg feed/day and another group was fed a basal diet (20IU/kg feed/day) for approximately 50 days prior to slaughter. Following frozen storage (-20°C for 8 weeks) semimembranosus muscles from basal and α-tocopheryl acetate supplemented cattle were minced and vacuum packaged, aerobically packaged or packaged under modified atmospheres (MAP) (30% O(2): 70% CO(2); 70% O(2): 30% CO(2); 80% O(2): 20% CO(2)). Samples were held under refrigerated (4°C) display (fluorescent lighting, 616 lux) for eight days. Vacuum-packaged samples were held under similar conditions but in complete darkness and allowed to bloom for a minimum of 4hr prior to taking colour readings. TBARS values and Hunter a values in minced beef were measured every two days. α-Tocopherol concentrations were significantly (p<0·05) higher in minced meat samples from the supplemented group than in the basal group. Significant (p<0·05) reductions in α-tocopherol concentrations in supplemented meat samples were observed with increased concentrations of oxygen in different packaging systems after eight days of refrigerated storage. TBARS values were reduced over the whole retail display period for all packaging systems when α-tocopheryl acetate supplemented beef was used. TBARS values increased as oxygen levels increased in MAP. Hunter a values showed that vitamin E supplementation in combination with vacuum packaging and MAP improved the colour stability of meat during the first 4 days of storage, however, the failure of MAP to extend meat colour for longer periods of time was probably the result of prior storage at -20°C for 8 weeks.  相似文献   
999.
Z.X. Xu    J. Zhou    D.Y. Zhao    X.G. Qiao    J.M. Yang 《Journal of food science》2010,75(1):C49-C54
ABSTRACT:  In this article, we prepared a novel imprinted polymer by a room temperature ionic liquid-mediated surface molecular imprinting technique in combination with a sol–gel process. This polymer was characterized by static and kinetic adsorption experiments and exhibited good recognition ability and offered fast kinetics for the adsorption of Para Red. A simple and sensitive analytical method, based on the coupling of molecularly imprinted solid phase extraction with high-performance liquid chromatography (HPLC), had been developed for determination of trace Para Red. With a loading flow rate of 0.42 mL min−1 for 25 mL, an enrichment factor of 1061 was achieved. Under the selected experimental condition, the detection limit (S/N = 3) of Para Red was 6.6 ng L−1, and the peak area precision (RSD) for 5 replicate detections of 0.15 μg L−1 Para Red was 4.1%. The applicability of this method for determination of the blank chili sauce sample, spiked with Para Red at 5 to 25 ng g−1 levels, was demonstrated, with recoveries ranging from 86% to 95%.
Practical Application: In this paper, a simple and sensitive analytical method, based on the coupling of molecularly imprinted solid phase extraction with high performance liquid chromatography, had been developed for determination of trace Para Red. It was applied to the analysis of spiking Para Red in chili sauce sample with satisfactory recovery and repeatability. This proposed method has the potential to be used for monitoring the illegal addition of Para Red in foods in the future due to its simple, reliable, rapid, and excellent precision.  相似文献   
1000.
The purpose of this research was to explain the combined effects of different total solid (TS) contents (20, 30 and 40%), stabilizer types (guar gum [GG], locust bean gum [LBG], carboxymethyl cellulose [CMC]) and overrun rates (OR) (30, 60 and 90%) on mix viscosity, melting time and hardness properties, which are the most important quality characteristics on industrial ice cream production. According to the investigation parameters; GG gave significantly less viscosity to the mix than LBG and CMC. In other words, LBG and CMC may be preferred to increase the viscosity of the mix or to limit the growth rate of ice crystals during recrystallization. Softness of ice creams and melting rapidity were linearly proportional to the increase of TS and ORs.

PRACTICAL APPLICATIONS


The most important parameters affected ice cream structure and quality are total solid, overrun and stabilizers. In many researches, the investigators have been focused of these parameters on only one or rarely two. In this research, the combined effects of different total solids (20, 30 and 40%), stabilizer types (guar gum, locust bean gum, carboxymethyl cellulose) and overrun levels (30, 60 and 90%) were investigated together in same mix and in industrial production conditions.  相似文献   
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