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Summary: Avocado seed (Persea americana Miller) is a by‐product of fruit processing and is considered a potential alternative source of starch. The use of starches from unconventional sources can be an alternative to replace modified starches as a functional ingredient in food systems. This study aimed to extract and characterise starch from avocado seed varieties Fortuna and Hass and produce aerogels. Starches were characterised by physical, chemical, thermal and morphological properties. The aerogels were produced by physical crosslinking and evaluated for water absorption capacity and physical properties. The starch extraction yield was 12%, and the granules had oval and spherical morphology. Amylose content ranged from 41.95% to 49.46%, and relative crystallinity from 22% to 25% for Hass and Fortuna, respectively. The Fortuna starch showed higher pasting temperature, peak viscosity, peak time and final viscosity values. Aerogels had excellent structural characteristics and had not deformed after 24 h of hydration; the Fortuna starch aerogels showed higher water absorption and mechanical resistance. The properties of avocado seed starch indicate a vast potential for application in food industries and for developing biodegradable packaging with excellent physical properties and excellent water retention capacity. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the physical and chemical alterations in rice starch modified by heat-moisture treatment (HMT) using an autoclave and a microwave, in association with avocado oil (AO), and evaluate the effects on thermal and structural properties, in vitro digestibility, and estimated glycemic index (eGI). Samples were adjusted to 30 % (w /w) moisture and 2, 4 and 8 % AO. HMT was conducted at 110 °C for 1 h in the autoclave (A0%, A2%, A4%, and A8%) and at 50 °C for 3 min in the microwave (M0%, M2%, M4%, and M8%). Both procedures did not alter the starch crystallinity pattern (type-A). Pasting viscosity, setback, relative crystallinity, and gelatinisation enthalpy decreased as the AO content increased in both HMT processes. The M8% showed reduced digestibility, decreased eGI (72.99, p < 0.05), and lower starch hydrolysis concentration (62.75 %, p < 0.05). The application of HMT with the addition of AO may be an interesting process for obtaining resistant starch since its content increased after both treatments (A8%, M4%, and M8%). The microwave process proved efficient, making it possible to use a lower temperature, less time, and less energy for modification and obtain starches with improved characteristics. • HMT reduced the viscosity and the retrogradation of the modified starches. • The inclusion complex between amylose-lipid was confirmed by peak V-type pattern. • The HMT associated with avocado oil presents reduced in vitro digestibility and eGI. • HMT conducted by microwave is quick and efficient in rice starch modification. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of thermosonication (TS) on tangerine juice using an ultrasonic bath (US, 35 kHz, 750 W) at 50°C/5 min, 50°C/10 min, 60°C/5 min, and 60°C/10 min, besides juice pasteurized at 85°C/5 min as control. The TS increased the titratable acidity, total soluble solids, and improved the juice homogeneity (p ≤.05), with discreet changes in the color parameters (L*, chroma, and hue). The treatment at 60°C was more effective against microbial growth, regardless of the processing time. Polyphenols and ascorbic acid remained at higher concentrations in the TS‐treated samples when compared to the control (p ≤.05), while lower carotenoids level was observed in the treatment at 50°C/5 min (p ≤.05). TS‐treated samples presented better antioxidant activity (p ≤.05) when compared to the control. Thus, TS treatment (60°C/5 min) may be a promising alternative for the preservation of bioactive compounds in tangerine juice. Practical applications: Several emerging technologies have been studied as alternatives to the conventional pasteurization of juices, like ultrasound, ultraviolet radiation, supercritic carbon dioxide, and high pressure hidrostatic. This study demonstrated that thermosonication (TS) can be used in the processing of tangerine juice using temperature of 60°C for 5 min, which exhibited the microbiological characteristics equivalent to the conventional pasteurization (85°C/5 min), without impairing the physicochemical and preserving the bioactive compounds, thus improving the antioxidant activity of the juice. The study contributes to recent research that suggests TS as a promising technology to be adopted in the fruit juice industry. [ABSTRACT FROM AUTHOR]