Effects of Lipid Solid Mass Fraction and Non-Lipid Solids on Crystallization Behaviors of Model Fats under High Pressure

Different fractions of fully hydrogenated soybean oil (FHSBO) in soybean oil (10–30% w/w) and the addition of 1% salt (sodium chloride) were used to investigate the effect of high-pressure treatments (HP) on the crystallization behaviors and physical properties of the binary mixtures. Sample microstructure, solid fat content (SFC), thermal and rheological properties were analyzed and compared against a control sample (crystallized under atmospheric condition). The crystallization temperature (Ts) of all model fats under isobaric conditions increased quadratically with pressure until reaching a pressure threshold. As a result of this change, the sample induction time of crystallization (tc) shifted from a range of 2.74–0.82 min to 0.72–0.43 min when sample crystallized above the pressure threshold under adiabatic conditions. At the high solid mass fraction, the addition of salt reduced the pressure threshold to induce crystallization during adiabatic compression. An increase in pressure significantly reduced mean cluster diameter in relation to the reduction of tc regardless of the solid mass fraction. In contrast, the sample macrostructural properties (SFC, storage modulus) were influenced more significantly by solid mass fractions rather than pressure levels. The creation of lipid gel was observed in the HP samples at 10% FHSBO. The changes in crystallization behaviors indicated that high-pressure treatments were more likely to influence crystallization mechanisms at low solid mass fraction

Optimization of anthocyanins extraction from black carrot pomace with thermosonication

PubMedID: 28764021A study was conducted to identify optimal ultrasound processing conditions (ultrasound energy density and temperature) to maximize the extraction of anthocyanin colorants from black carrot pomace. The treatment maximized the yield of five different anthocyanin compounds from black carrot pomace with cyanidin-3-xyloside-galactoside-glucoside-ferrulic acid (C3XGGF, 60.85–74.22 mg/L) as the most abundant anthocyanin compound, followed by cyanidin-3-xyloside-galactoside (C3XG, 49.56–70.12 mg/L). The response surface models predicted that if extraction conditions were conducted at 183.1 J/g energy density and 50 °C, the yield of various anthocyanin compounds would be maximized from the black carrot pomace. Response surface models were developed correlating anthocyanin yield with ultrasonication treatment parameters. The study showed the synergy of combining ultrasonication and temperature for the extraction of anthocyanin pigments from black carrot pomace. Results of the study also further demonstrate the potential of ultrasonication technology as a tool for the extraction of valuable components waste products from fruits and vegetables juice industry. © 2017 Elsevier Lt

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Not AvailableEffect of aqueous extracts of pomegranate peel (PPE) and tamarind pulp (TPE) on lethality of pressure assisted thermal processing (PATP) against Bacillus amyloliquefaciens Fad 82 spores was investigated. B.amyloliquefaciens spores (≈108 CFUml−1) were suspended in deionized water (DIW), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer PPE, and TPE (1% w/v in DIW, pH-6) and beef broth with or without PPE and TPE (0.45% w/v). Samples were subjected to pressure assisted thermal processing (PATP, 600 MPa, 105 ◦C), and thermal processing (TP; 0.1 MPa, 105 ◦C) for 0 (come-up time), 0.5, 1, 3, and 5min. Beef broth samples were also pressure treated (HPP; 600 MPa, 35 ◦C) for 3 and 5min. Dormant spore survivors were enumerated by spread-plate technique. Heat shock (80 ◦C for 15min) was used to enumerate the heat sensitive spores. A 5-min PATP reduced spore survivors counts to below 1-logCFUml−1 (≈6.5–7.0 log reduction) in PPE and TPE as compared to 2.5-log and 3.1-log in DIW and HEPES buffer, respectively. 3min PATP treatment reduced the spore survival to 3.58 and 2.1 logCFUml−1 in beef broth and beef broth+natural extract, respectively. TP and HPP processing could inactivate the spores only by 0.5–1.2 logCFUml−1. PPE and TPE are found to enhance the efficacy of PATP.Not Availabl

Opportunities and challenges in high pressure processing of foods

Consumers increasingly demand convenience foods of the highest quality in terms of natural flavor and taste, and which are freedom additives and preservatives. This demand has triggered the need for the development of a number of nonthermal approaches to food processing, of which high-pressure technology has proven to be very valuable. A number of recent publications have demonstrated novel and diverse uses of this technology. Its novel features, which include destruction of microorganisms at room temperature or lower, have made the technology commerically attractive. Enzymes forming bacteria can be by the application of pressure-thermal combinations. This review aims to identify the opportunities and challenges associated with this technology. In addition to discussing the effects of high pressure on food components, this review covers the combined effects of high pressure processing with: gamma irradiation, alternating current, ultrasound, and carbon dioxide or anti-microbial treatment. Further, the applications of this technology in various sectors-fruits and vegetables, dairy and meat processing-have been dealt with extensively. The integration of high-pressure with other matured processing operations such as blanching, dehydration, osmotic dehydration, rehyrdration, frying, freezing/thawing and solid-liquid extraction has been shown to open up new processing options. The key challenges identified include: heat transfer problems and resulting non-uniformity in processing, obtaining reliable and reproducible data, for process validation, lack of detailed knowledge about the interaction between high pressure, and a number of food constituents, packaging and statutory issues

Impact of ultra-shear technology on quality attributes of model dairy-pea protein dispersions with different fat levels

This study investigated the impact of ultra-shear technology (UST) processing on dairy-pea protein dispersions with different fat levels. Raw milk, skim milk, and cream, as well as model dispersions with combinations of dairy products and pea protein (i.e., raw milk with pea protein, skim milk with pea protein, and cream with pea protein) were employed as test samples. UST experiments were conducted at a pressure of 400 MPa and 70 °C shear valve exit temperature. The UST treatment increased the viscosity of the dispersions and the increases depended on the fat level. Dairy-pea protein dispersions from raw milk and skim milk were shear thinning and mathematically described by the power-law model defined by the consistency coefficient, K (Pa·sn) and the flow behavior index, n. UST treated cream + pea protein dispersions produced structures with gel-like characteristics. Microstructure and particle size analysis determined by laser scanning microscope revealed a reduction in particle size after UST treatment in raw milk + pea protein and skim milk + pea protein dispersions up to 7.55 and 8.30 μm, respectively. In contrast, the particle mean diameter of cream + pea protein dispersions increased up to 77.20 μm after the UST treatment. Thus, the effect of UST on the particle size and rheological behavior of the dispersions depended on the fat level. UST-treated dispersions were stable with no visible phase separation or sedimentation upon centrifugation at 4000×g for 30 min (4 °C). Heat treatment and freeze–thaw treatment of UST-treated samples showed stable blends immediately after the treatments, but subsequent centrifugation showed solid separation. Results from the study suggest that UST is a potential technology to produce stable dairy + pea protein liquids foods with different rheological characteristics for diverse applications