RESUMO
Banana starches (BS) were isolated from Enano, Morado, Valery and Macho cultivars. The BS possessed B-type crystallinity and an amylose content varying from 19.32 to 26.35%. Granules had an oval morphology with different major-to-minor axis ratios, exhibiting both mono- and bi-modal distributions and mean particle sizes varying from 32.5 to 45 µm. BS displayed zeta-potential values ranging between -32.25 and -17.32 mV, and formed gels of incipient to moderate stability. The enthalpy of gelatinization of BS affected the crystalline order stability within the granules. In-vitro digestibility tests showed fractions as high as 68% of resistant starch. Rheological oscillatory tests at 1 Hz showed that BS dispersions (7.0%, w/w) exhibited Type III behaviour, attributed to the formation of a continuous phase complex three-dimensional amylose gel reinforced by swollen starch granules acting as fillers. Amylose content and granules morphology were the main factors influencing the BS properties.
Assuntos
Fenômenos Químicos , Digestão , Musa/química , Reologia , Amido/química , Amido/metabolismo , Temperatura , Indústria Alimentícia , Humanos , SolubilidadeRESUMO
Saturated animal fat was replaced in pork pâté with pre-emulsified canola in a 3% sodium caseinate/0.5% xanthan gum solution in order to obtain a stable oily phase. Fat was replaced with different proportions of emulsified canola oil. The inclusion of emulsified oil in pâté enhanced cocking yield and moisture but increased fluids release. Nonetheless, total fat content remained practically constant, meaning no detrimental effect on caloric content. Replacing 50% of lard with emulsified oil did not affect color of the samples. Texture was improved since emulsified oil addition resulted in softer and more spreadable pâté. Samples with 50% of emulsified oil were more stable to lipid oxidation at 8 days of storage, with lower thiobarbituric acid-reactive substances and volatile compounds resulting from oxidation reactions. Emulsified canola can be employed to replace fat until 50% in pâté or liver sausage with good functional properties, improving texture and reducing lipids rancidity.
Assuntos
Emulsificantes/química , Substitutos da Gordura/química , Ácidos Graxos Monoinsaturados/química , Manipulação de Alimentos , Fígado/química , Produtos da Carne/análise , Animais , Caseínas/química , Fenômenos Químicos , Preferências Alimentares/etnologia , Armazenamento de Alimentos , Humanos , México , Oxirredução , Pigmentação , Polissacarídeos Bacterianos/química , Óleo de Brassica napus , Sensação , Sus scrofa , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Água/análiseRESUMO
In this work the compound obtained from yeast culture extract (YCE) that stimulated the activity of an anaerobic cellulolytic consortium (ACC) was characterized. YCE were obtained at different pH (4, 7 and 10) and ultra-filtered 300 and 30 kDa membranes (UYE). The 30 kDa UYE was heated to 60 °C, 90 °C and 120 °C and gel filtered (GYF). Mid infrared spectroscopy, protein and carbohydrate analysis of GYF were conducted. Results showed that YCE, UYE and GYF significantly stimulated (p < 0.05) the biomass production, acetate concentration and carboxymethyl cellulase activity of the ACC, in relation to the control. The GYF had an estimated molecular mass of 4 kDa. Mid-infrared and biochemical analysis of GYF suggested that the active compound is a peptide.
