Tempering method for chocolate containing milk-fat fractions

Anhydrous milk fat (AMF) was fractionated by a two-stage dry fractionation process to produce three fractions—high-(HMF), middle-(MMF), and low-melting (LMF). The effect of replacing 12.2–40% by weight of cocoa butter with these fractions on the tempering profile of milk chocolate was studied. Degree of temper was evaluated by differential scanning calorimetry, and expressed as the ratio of enthalpies of melting for higher-stability polymorphs to those of lesser stability. The degree of temper was dependent on the crystallization time and temperature, and the type and quantity of milk-fat fraction in the formulation. Chocolates containing AMF or its fractions in concentrations of up to 20 wt% (total fat basis) were tempered after a conventional thermocycling tempering process (50°C/30 min, 27.7°C/4 min, 31°C/2 min) to obtain products with good contraction and mold release properties. For those milk chocolate formulations that did not temper by the conventional method and resulted in poor contraction and mold release, a new tempering protocol was developed. Lower crystallization temperatures and/or longer holding times were required at concentrations of AMF, MMF, or LMF above 20%. Chocolate containing HMF required slightly higher crystallization temperatures because of high viscosity. Chocolates containing up to 35% HMF and up to 40% of the total weight of fat in the chocolate of AMF, MMF, and LMF were successfully tempered by adjusting crystallization time and temperature.     

Structured lipids from rice bran oil and stearic acid using immobilized lipase from Rhizomucor miehei

The major objective of the present study was to prepare structured lipids rich in stearic acid from rice bran oil (RBO) using immobilized lipase (IM 60) from Rhizomucor miehei. The effects of incubation time and temperature, substrate molar ratio, and enzyme load on incorporation of stearic acid were studied. Acidolysis reactions were performed in hexane. Pancreatic lipase‐catalyzed sn‐2 positional analysis and tocopherol analyses were performed before and after enzymatic modification. The kinetics of the reaction was studied and maximum incorporation of stearic acid was observed at 6 h, at 37 °C, when the triacylglycerol and stearic acid molar ratio was maintained at 1 : 6 and the enzyme concentration was 10% of total substrates weight. Stearic acid in RBO after acidolysis was increased from 2.28 to 48.5%, with a simultaneous decrease in palmitic, oleic and linoleic acids. HPLC analysis of tocopherols and tocotrienols was carried out and their content in modified RBO was not significantly affected compared to that of native RBO. The oryzanol content of the modified RBO was reduced from 1.02 to 0.68%. Melting and crystallizing characteristics of the modified fat were studied using differential scanning calorimetry. The total solid fat content at 25 °C increased from 26.12 to 34.8% with an increase in stearic acid incorporation into RBO from 38 to 48%, but it was comparatively less than for cocoa butter and vanaspati. However, the modified RBO completely melted at 37 °C and was useful as plastic fat for various culinary purposes, bakery and confectionary applications. The results of the present study indicated that structured lipids prepared from RBO rich in stearic acid retained their beneficial nutraceuticals; in addition, they do not contain any trans fatty acids.     

Heat-resistant cocoa butter extenders from mahua (Madhuca latifolia) and kokum (Garcinia indica) fats

Cocoa butter extenders with heat-resistant properties were prepared using mahua and kokum fats. The stearin fraction [Fraction (Fr.) 1, 77–80% yield] obtained by solvent fractionation of 50:50 blends of these fats showed a steep melting profile with a higher solid fat content (SFC) at 32.5°C than cocoa butter, even after mixing with it at 25 or 50% levels. The solidification characteristics showed that the Fr. 1 had a supercooling property similar to cocoa butter, but showed higher temperature rise with less crystallization time on the cooling curve, which is advantageous for chocolate molding. Fr. 1 was compatible with cocoa butter at all proportions, as revealed by cooling curves and isothermal solid diagrams. The stearin fraction obtained by dry fractionation of mahua/kokum blend (Fr. 2, 77% yield), though, had similar solidification characteristics and showed lower SFC compared to that of Fr. 1. Fr. 1 and Fr. 2 have high levels of 2-oleo-distearin triacylglycerols (46–51%), which are responsible for better stand-up property at high temperatures compared to cocoa butter. The suitability of the blends of mahua/kokum fats and mahua stearin/kokum fats as cocoa butter extenders was also evaluated. The isothermal solid diagrams showed complete miscibility of the two fats fractions. The results showed that a series of cocoa butter extenders with varying melting characteristics could be prepared by fractionating and by physical blending of mahua and kokum fats in selected proportions.     

Effect of Diglycerides on the Solidification Properties of Sal (Shorea robusta) Fat

The solidification properties of commercially refined and bleached sal fats have been investigated. The inconsistency in their solidification behaviour has been shown to be due to the presence of minor components namely the triglycerides containing 9,10-dihydroxystearic acid (DHS-TGs) and diglycerides (DGs). The effect of DGs individually and in combination with DHS-TGs on the solidification properties of purified normal triglycerides (TGs) of sal fat has shown that DGs increased the α-lifetime of the crystals, delayed the crystallization, reduced heats of fusion and reduced solid fat indices of TGs at all temperatures. The effect of DGs could be counteracted by DHS-TGs the effect of which was opposite to that of DGs. When DGs and DHS-TGs incorporated together, in equal concentrations the effect of DHS-TGs was more perceptible. When the proportion of DGs was more than that of DHS-TGs, the effect of DGs was discernable particularly on the cooling curve. It is concluded that the concentration of both DGs and DHS-TGs has to be kept at a minimum in order to get fat fractions with uniform solidification properties.     

Detection of Spammers in Twitter marketing: A Hybrid Approach Using Social Media Analytics and Bio Inspired Computing

Customer engagement is drastically improved through Web 2.0 technologies, especially social media platforms like Twitter. These platforms are often used by organizations for marketing, of which creation of numerous spam profiles for content promotion is common. The present paper proposes a hybrid approach for identifying the spam profiles by combining social media analytics and bio inspired computing. It adopts a modified K-Means integrated Levy flight Firefly Algorithm (LFA) with chaotic maps as an extension to Firefly Algorithm (FA) for spam detection in Twitter marketing. A total of 18,44,701 tweets have been analyzed from 14,235 Twitter profiles on 13 statistically significant factors derived from social media analytics. A Fuzzy C-Means Clustering approach is further used to identify the overlapping users in two clusters of spammers and non-spammers. Six variants of K-Means integrated FA including chaotic maps and levy flights are tested. The findings indicate that FA with chaos for tuning attractiveness coefficient using Gauss Map converges to a working solution the fastest. Further, LFA with chaos for tuning the absorption coefficient using sinusoidal map outperforms the rest of the approaches in terms of accuracy.     

Review and Implementation of Topic Modeling in Hindi

ABSTRACT

Due to the widespread usage of electronic devices and the growing popularity of social media, a lot of text data is being generated at the rate never seen before. It is not possible for humans to read all data generated and find what is being discussed in his field of interest. Topic modeling is a technique to identify the topics present in a large set of text documents. In this paper, we have discussed the widely used techniques and tools for topic modeling. There has been a lot of research on topic modeling in English, but there is not much progress in the resource-scarce languages like Hindi despite Hindi being spoken by millions of people across the world. In this paper, we have discussed the challenges faced in developing topic models for Hindi. We have applied Latent Semantic Indexing (LSI), Non-negative Matrix Factorization (NMF), and Latent Dirichlet Allocation (LDA) algorithms for topic modeling in Hindi. The outcomes of the topic model algorithms are usually difficult to interpret for the common user. We have used various visualization techniques to represent the outcomes of topic modeling in a meaningful way. Then we have used the metrics like perplexity and coherence to evaluate the topic models. The results of Topic modeling in Hindi seem to be promising and comparable to some results reported in the literature on English datasets.     

Optimum Blend of Chitosan and Poly-(��-caprolactone) for Fabrication of Films for Food Packaging Applications

The present work deals with the preparation and characterization of the chitosan and poly-ε-caprolactone (PCL) solution-casted blended films in various proportions (chitosan–PCL ratio 90:10, 80:20, and 70:30). The films were casted and dried at 55 °C, which were characterized based on the mechanical, barrier, thermal, and microscopic properties. The film prepared from chitosan to PCL ratio 80:20 resulted in increase percentage elongation by 20.56% as compared to pure chitosan film. Fourier transform infrared spectrum indicated a shift in peak of absorption from 1743.9 to 1724.8 cm⁻¹ due to carbonyl group of PCL indicating the miscibility and interaction between the PCL and chitosan. Scanning electron microscopy revealed that PCL appeared as a co-continuous phase with chitosan for ratio 80:20, confirmed the interaction between chitosan and PCL. The above study indicated that the properties of chitosan films can be modified with the addition of PCL and may find its versatile use in food packaging.     

Quality changes in trans and trans free fats/oils and products during frying

The physico-chemical changes occurring during simulated frying conditions at 180 °C for 24 h in trans free speciality fat, trans rich vanaspati and PUFA rich sunflower oil were evaluated. The samples became darker, the polar components and viscosity increased as the time of heating increased. The oxidative stability as determined by peroxide, anisidine values and TOTOX number, increased, whereas the total unsaturated fatty acids and iodine value decreased with time of heating in all the samples. The trans free speciality fat was as stable as vanaspati showing similar quality parameters, while sunflower oil showed a higher degree of deterioration. The layered fat used for traditional products such as Chiroti dough consisted 14% trans fatty acids (TFA), which was reduced to 4–7%, and correspondingly 18:2 was increased in the product upon frying in sunflower oil. Accordingly, trans fatty acids increased in the medium from 0 to 7.5%. Chiroti when fried in vanaspati with TFA 18%, their content in both products (16%) and in medium (17%) remained similar.     

Improving Plasticity of Milk Fat for Use in Baking by Fractionation

Milk fat is soft with a low solids content at all temperatures up to 37 °C, which makes its usage limited. To extend its usage, the fat was fractionated to obtain stearin (St) with a 50–55% yield by dry fractionation. The stearin was found to contain an increased solids content at all temperatures and to have improved plasticity compared to its native fat. The physical properties of St were found to be similar to those of commercial bakery shortenings or vanaspati. The melting profiles and the solidification properties of milk fat St are similar to those of commercial bakery shortening. Also, St does not require extended stabilization or tempering, as it transferred to the most stable form quickly like commercial bakery fat. Milk fat St showed higher proportions of saturated fatty acids including those with short chains, compared to commercial vanaspati, the later having a high trans fatty acid content (15%). The olein obtained could also be used as a cooking medium or as a salad oil since it contains a lower solids content at ambient temperatures compared to its parent milk fat.