酒精溶液浸泡处理对爆裂玉米微波常压与微波真空膨化的影响

本实验以膨化率为指标研究了酒精溶液浸泡处理对爆裂玉米微波常压与微波真空膨化的影响。实验证明 :经过 40 %酒精溶液处理后 ,当真空度为 93 3kPa时 ,爆裂玉米能够保持较好的爆花质量 ;爆裂玉米微波真空膨化比微波常压膨化具有较好的膨化特性。     

酒精溶液浸泡处理对爆裂玉米微波常压与微波真空膨化的影响

本实验以膨化率为指标研究了酒精溶液浸泡处理对爆裂玉米微波常压与微波真空膨化的影响。实验证明：经过40％酒精溶液处理后，当真空度为93．3kPa时，爆裂玉米能够保持较好的爆花质量；爆裂玉米微波真空膨化比微波常压膨化具有较好的膨化特性。     

爆裂玉米的微波膨化特性研究

以爆裂玉米为原料,研究了在微波作用条件下它的微波膨化特性,探讨了不同的处理方法对其微波膨化率的影响,实验证明：爆裂玉米的水分含量大小是影响其微膨化率的主要因素之一,低浓度的食盐和乙醇溶液浸渍处理,能够提高爆裂玉米的微波膨化等。     

水分对微波真空膨化爆裂玉米的影响

以膨化率为指标研究了水分对微波真空膨化爆裂玉米的影响。实验证明，水分含量的大小是影响膨化率的主要因素之一。在微波真空条件下，爆裂玉米获得膨化效果的水分含量是：爆裂玉米获得最佳膨化效果的水分含量是：真空度26.66KPa时，为11.3%；真空度93.3KPa时，为20.4%。     

氯化钠对爆裂玉米微波真空膨化的影响

用自行研制的微波真空装置探讨了氯化钠对爆裂型玉米微波真空膨化的影响.结果表明,爆裂型玉米的膨化率与氯化钠含量之间存在非线性关系.文章初步分析了实验现象,对微波真空膨化机理的研究方向提出了自己的看法.     

爆裂玉米的化学成分对微波膨化率的影响

通过测定黄玫瑰型３种不同产地的爆裂玉米的水分，淀粉，蛋白质含量，研究其对微波膨化效果的影响，同时对乙醇处理后的爆裂玉米的微波膨化效果，进行了初步探讨，结果表明，爆裂玉米的微波膨化率随淀粉含量的增加而提高，尤其是支链淀粉的含量；蛋白质和水分通过与淀粉之间的相互作用，影响爆裂玉米的微波膨化效果，微波膨化后，爆裂玉米的淀粉含量减少，低聚糖含量增加，蛋白质含量不变，乙醇浸渍后，可提高爆裂玉米的微波膨化率。     

爆裂玉米的水分含量对其油炸膨化率和微波膨化率的影响

研究了水分含量对黄玫瑰型爆裂玉米的两种膨化效果的影响。结果表明黄玫瑰型爆裂玉米含水量为13.85%时,油炸膨化率为最大,是19.8;含水量为13.67%时,微波膨化率为最大,是17.9。水分含量在8%～20％范围,油炸膨化率大于微波膨化率。     

真空微波干燥重组鱼丸的研究

以鱼肉为主要原料,采用真空微波膨化技术制作松脆脱水重组鱼丸.通过大量单因素实验,研究了各种辅料和蒸煮时间对重组鱼丸膨化率和感官品质的影响;进一步采用真空微波膨化技术,研究了微波功率、真空度对重组鱼丸干燥速率、膨化率和感官品质的影响.结果表明,重组鱼丸的适宜配方和工艺条件为:鱼肉(经过预处理)100 g,糯米粉10 g,猪肥膘4 g,食盐2 g,白砂糖6 g,葱姜蒜粉0.6g;蒸煮时间为6 min,真空微波炉的真空度和微波功率分别为-0.095MPa和180W,干燥时间为15 min,得到的成品表面呈现均匀的淡黄色,有鲜美的鱼肉味,口感细腻、松脆.     

食盐对淀粉物料微波膨化的影响研究

研究了食盐对微波加热的影响作用,探讨了淀粉物料中添加食盐后微波加热的特性、机制及加热、膨化效果的改变情况.结果表明,食盐的添加增强了微波对淀粉物料的加热效果,使得物料膨化时间提前,产品膨化率及膨化速率大大提高;使中心加热表现为周边加热,且随着盐含量的增加而表现趋于明显;使膨化产品质构改变,产品质量提高.     

食盐对淀粉物料微波膨胀化的影响研究

研究了食盐对微波加热的影响作用,探讨了淀粉物料中添加食盐后微波加热的特性,机制及加热,膨化效果的改变情况。结果表明,食盐的添加增强了微波对淀粉物料的加热效果,使得物料膨化时间提前,产品膨化率及膨化率大大提高;使中心加热表现为周边加热,且随着盐含量的增加而表现趋于明显;使膨化产品质构改变,产品质量提高。     

Pericarp Thickness and Other Kernel Physical Characteristics Relate to Microwave Popping Quality of Popcorn

The popping performance of 18 popcorn hybrids was studied using 2 microwave treatments, with and without salt, and 1 conventional method. Differences in popping quality indices between the 2 microwave treatments, indicated a negative effect of salt on popping for the majority of hybrids. Pericarp thickness, kernel volume, sphericity, diameter ratio, thousand kernel weight, hardness, and density were investigated. Pericarp thickness gave highest correlation with expansion volume in microwave and conventional popping while sphericity correlated slightly better in unsalted microwave popping. Regression models, which predict expansion volume in terms of pericarp thickness and kernel shape and size, were developed for both microwave and conventional popping.     

The effects of ingredients on popcorn popping characteristics

Response surface methodology was used to evaluate the effects of ingredients on popcorn popping characteristics. The effects of different ingredients on the expansion volume and unpopped kernel ratio of popcorn in a conventional popper and a microwave oven were evaluated and optimized by response surface methodology. The regression models were significant and had R² value in the range of 0.919–0.956. The optimum levels of ingredients for microwave popping were 4.4% salt, 5.9% vegetable oil, 0% sodium bicarbonate and 16.4% butter, this formulation giving an expansion volume of 33.1 mL g^?1. In the case of conventional popping, the maximum expansion volume of 37.3 mL g^?1 was obtained for 3.5% salt, 6% vegetable oil, 0.10% sodium bicarbonate and 12.9% butter.     

不同油爆条件对不同类型爆裂玉米爆花特性影响

为研究不同油爆条件对不同类型爆裂玉米爆花特性影响,选取蝶型和球型两类爆裂玉米,分析不同加油量和处理温度对其特性的影响。研究表明,对于膨爆倍数,加油量和处理温度对不同类型爆裂玉米的影响不显著,而膨爆倍数在40%~50%的加油量时为最佳,等体积下的蝶型需油量更多,蝶型的适宜处理温度低于球型。爆花温度受加油量影响明显且呈显著正相关,而处理温度影响不明显,不同加油量和处理温度下,蝶型平均爆花温度高于球型。爆花起始和总时间受加油量影响并呈显著负相关,处理温度影响不显著,但随处理温度增加呈下降趋势。由此可见,油爆时爆花温度和时间主要受加油量影响,而蝶型和球型爆裂玉米适宜处理温度不同。     

Studies on Popping of Popcorn in a Microwave Oven

The popping performances of five different varieties of popcorn with moisture contents ranging from 8–18% w.b. were studied using a Litton microwave oven. Each variety was found to have different optimum moisture contents for maximum expansion volume and for minimum unpopped kernel ratio. In one variety (M-045) the expansion volume correlated with the size of the kernels. Long term frozen storage increased the popped volume in comparison with storage at room temperature. The effect of salt and oil on the popping performance of popcorn was complex. The presence of any surface damage on the kernels decreased the expansion volume significantly.     

EFFECTS OF KERNEL PROPERTIES AND POPPING METHODS ON POPCORN QUALITY OF DIFFERENT CORN CULTIVARS

Three popcorn genotypes, Koç Cin (composite), Nermin Cin and Ant Cin-98 (hybrid) were investigated for the effects of kernel size (4  <  D  <  5 and 5  <  D  <  6), popping methods (conventional and microwave) and moisture content (10, 12 and 14%) on popcorn quality. The relationships between physical kernel properties and popping characteristics were also researched. The Nermin Cin popcorn cultivar had the highest expansion volume, flake size and the lowest percentage of unpopped kernel values among genotypes. 5  >  D  >  6 mm kernel fraction and the conventional method produced higher popcorn quality in all popcorn cultivars. The optimum moisture levels for the highest expansion volume changed between 12 and 14% for different cultivars. The correlation coefficient between kernel properties (width, sphericity, L , a and b) and expansion volume were found significant ( P <  0.01) in microwave popping method. Color a had high direct effects on expansion volume in conventional and microwave popping methods according to path coefficient analysis. L values of popcorn cultivars negatively correlated with expansion volume in both popping methods.

PRACTICAL APPLICATIONS

Physical parameters like width, sphericity and color values were found important in predicting popping quality. Color values should be used to predict expansion volume instead of classic physical properties for ease ofmeasurement. Conventional popping method, 5 > D > 6 kernel size and 12–14% moisture content parameters should be used for optimum popcorn quality.     

Physical Properties as Indicators of Popping Characteristics of Microwave Popcorn

Nondestructive physical property measurements, such as kernel size, sphericity, specific gravity and elastic deformation were evaluated as indicators of the popping characteristics of microwave popcorn. A greater expansion volume was observed in varieties having sphericity values greater than 0.70. Within a given variety, larger kernel sizes resulted in a lower unpopped kernel ratio and the expansion volume and flake size were higher for kernels with a higher specific gravity. The elastic deformation was found to have no correlation with microwave popping.     

The Relation Between Final Popped Volume of Popcorn and Thermal-Physical Parameters

Previous studies have shown that popping volume of popcorn is affected by water content, and that popping volume increases with an increase in water content up to an optimal value, and then the volume decreases with any additional moisture. The aim of this study was to explore the mechanism responsible for the peak in popping volume as a function of water content. Popcorn was equilibrated to various water contents from 6.7 to 16.5 g/100 g d.b. over salt solutions (a_w0.33-0.82), and popped by an air popper. Maximal popping volume occurred at a water content of 15.5 g/100 g d.b. (a_w=0.745 at room temperature) while the popping temperature dropped with increasing water content. Thermal analysis of the popcorn by DSC showed no significant effect of the moisture on the melting temperature orT_g of the unpopped endosperm. However, the decrease of the pericarp melting temperature correlated with an increased water content. The results suggest that elevated water contents cause a rubbery collapse of the pericarp at lower temperature. The temperature of this melting event decreases by ∼7 °C over the 6-16.5 g/100 g moisture range. Thus, as the water content increases, the pressure in the kernel at the popping moment is lower, causing less expansion and lower final popped volume.     

Emissions from cooking microwave popcorn

This study characterized chemicals released into a chamber in the process of cooking microwave popcorn. Seventeen types of microwave popcorn from eight different brands were studied. The work proceeded in two phases: phase one investigated chemicals emitted during popping and opening, phase two investigated chemicals emitted at discrete intervals from 0-40 minutes post-pop opening. The research was performed using a microwave oven enclosed in a chamber with ports for air sampling of particulate matter (PM) and volatile organic compounds (VOCs). VOCs in the air samples were identified and quantified using gas chromatography/mass spectrometry (GC/MS). PM was characterized using both an aerodynamic particle sizer (APS) and a scanning mobility particle sizer (SMPS) to cover a full range of emitted sizes. The compounds measured during popping and opening included butter flavoring components such as diacetyl, butyric acid, acetoin, propylene glycol, 2-nonanone, and triacetin and bag components such as p-xylene and perfluorinated alcohol 8:2 telomer. The greatest chemical quantity is emitted when the bag is opened post-popping; more than 80% of the total chemical emissions occur at this time.