Impact of cyclic and continuous dry heat modification on the structural, thermal, technological, and in vitro digestibility properties of potato starch (Solanum tuberosum L.): A comparative study.

Dry heat treatment (DHT) has been demonstrated as a viable method for starch modification, offering benefits due to its environmentally friendly process and low operational costs. This research modified potato starch using different DHT conditions (continuous-CDHT and cyclic-RDHT), with durations ranging from 3 to 15 h and 1 to 5 cycles, at 120 °C. The study investigated and compared the structural, thermal, pasting, and morphological properties of the treated samples to those of untreated potato starch, including in vitro digestibility post-modification. DHT altered the amylose content of the biopolymer. X-ray diffraction patterns transitioned from type B to type C, and a decrease in relative crystallinity (RC%) was observed. Morphological changes were more pronounced in starches modified by RDHT. Paste viscosities of both CDHT and RDHT-treated starches decreased significantly, by 61.7 % and 58.1 % respectively, compared to native starch. The gelatinization enthalpy of RDHT-treated starches reduced notably, from 17.60 to 16.10 J g-1. Additionally, starch digestibility was impacted, with cyclic treatments yielding a significant increase in resistant starch content, notably an 18.26 % rise. These findings underscore the efficacy of dry heat in enhancing the functional properties of potato starch.

Sweet Potato (Ipomoea batatas L): a Versatile Raw Material for the Food Industry

Abstract Sweet potato (SP) starchy roots have a broad range of colors, high-quality nutritional composition including bioactive substances (anthocyanins and β-carotene), vitamins, minerals, dietary fiber and starch. Several studies report the versatility of this root crop as part of the human diet and its possible health benefits. In this review the SP chemical composition, nutritional properties and its potential use in food processing for developing nutritious and healthy products are explored. Due to the adaptation of sweet potatoes to several agricultural managing conditions, accepting low technology /low cost with reasonable performance, it has called attention as a strong candidate of accessible functional food market.

Assessment of Microbial Contamination in Products of Animal Origin: Stretched-curd Cheese, Yogurt and Fresh Sausage

Abstract Animal products are sources of microbiological contamination when the process has hygienic-sanitary control fails. Therefore, this work aims the evaluation of the pathogenic microorganisms presented in samples from the Brazil southern region of yogurt (N = 101), stretched curd cheese (N = 31), fresh sausage (N = 22) and processing water (N = 63). Analyses of coliforms at 45 °C, Staphylococcus aureus, Salmonella sp. and Escherichia coli were performed. Analysis indicated processing water is an important contamination source to be monitored, because the majority of samples presented results above the regulation limits. Thermal treatment and fermentation such as stretched curd cheese and yogurt appeared to be more stable against contamination during processing. In this study, for coliforms at 45 °C, only one cheese sample and 12% of total yogurt samples exceeded the Brazilian legislation limit. None of sausage samples presented any contamination. On the other hand, values found in both processing water and dairy products indicated failures in application and monitoring of good manufactured practices.