Efeito do ultrassom na sedimentação, turbidez e microestrutura de suco de laranja com cenoura / Effect of ultrasound on sedimentation, turbidity, and microstructure of orange-carrot juice

O ultrassom tem sido apontado como alternativa à pasteurização na conservação de sucos, com intuito de minimizar os prejuízos observados durante o processamento térmico tradicional. Deste modo, objetivou-se avaliar o tratamento com ultrassom na sedimentação da polpa, turbidez e microestrutura de suco misto de laranja com cenoura. Porções de suco (400 mL) foram submetidas a pasteurização (90 °C/ 30 s), ultrassom 40 kHz a 40° C, 50 °C e 60 °C (por 5 e 10 min). Além disso, foi avaliado o suco não tratado. Todas as condições de tempo e temperatura dos tratamentos com ultrassom proporcionaram aumento da turbidez. Ultrassom a 60 °C por 5 e 10 minutos retardaram o processo de sedimentação da polpa. Mudanças na estrutura e ruptura da parede celular foram evidenciadas com maior nitidez na amostra tratada a 60 °C por 10 minutos no ultrassom.

Analysis of air quality in selected areas of a poultry processing plant with the use of a microbiological air sampler

The aim of the study was to analyze the air quality in selected production facilities specified as the so-called "high-risk zones". Air samples were analyzed using either the sedimentation or the impaction methods. The impaction method showed the applicability of the air sampler in in-situ measurements. An increase in the numbers of aerobic bacteria was observed in most air sample collection sites as the duration of the production time increased. At the three successive dates, it amounted to 163 cfu/m3, 205 cfu/m3, and 324 cfu/m3, respectively. Such dependence was not observed by the of sedimentation method. It was stated that the impaction technique is better to precisely determine numbers of bacteria, yeast, and molds in the air of poultry processing areas. Analyses showed a high level of microbial air contamination in the examined production areas in relation to the guidelines applied in the assessment of indoor air contamination. Based on the recorded results, it was recommended to undertake immediate corrective actions, consisting in the replacement of filters in the refrigeration and air conditioning equipment, as well as to provide comprehensive training for the employees working in the selected facilities.

Analysis of air quality in selected areas of a poultry processing plant with the use of a microbiological air sampler

The aim of the study was to analyze the air quality in selected production facilities specified as the so-called "high-risk zones". Air samples were analyzed using either the sedimentation or the impaction methods. The impaction method showed the applicability of the air sampler in in-situ measurements. An increase in the numbers of aerobic bacteria was observed in most air sample collection sites as the duration of the production time increased. At the three successive dates, it amounted to 163 cfu/m3, 205 cfu/m3, and 324 cfu/m3, respectively. Such dependence was not observed by the of sedimentation method. It was stated that the impaction technique is better to precisely determine numbers of bacteria, yeast, and molds in the air of poultry processing areas. Analyses showed a high level of microbial air contamination in the examined production areas in relation to the guidelines applied in the assessment of indoor air contamination. Based on the recorded results, it was recommended to undertake immediate corrective actions, consisting in the replacement of filters in the refrigeration and air conditioning equipment, as well as to provide comprehensive training for the employees working in the selected facilities.(AU)