Injury Threshold of Oral Contact with Hot Foods and Method for Its Sensory Evaluation

Impact of Very Hot Drink Consumption Habits, Age, and Sex, on Taste Sensitivity

The temperature range for consuming hot drinks includes temperatures that can damage cells on the tongue. We hypothesized that the consumption of very hot drinks can lead to a decrease in the ability to perceive low concentrations of tastants. We evaluated the ability to perceive low concentrations of five prototypical sapid compounds in 42 women and 40 men aged 18-65. A questionnaire made it possible to collect the usual frequencies (number of unit/day) and consumption temperature levels (medium hot/very hot) for four very common hot drinks (coffee, tea, herbal infusions, and hot chocolate). Our results showed that subjects who consumed very hot drinks (versus medium hot) were less sensitive to sweet (p = 0.020) and salty (p = 0.046) tastes. An aggravating effect of high consumption frequencies was only shown for sweet taste (p = 0.036). Moreover, our data also showed that women were more sensitive than men to sour, bitter, and umami tastes (p values < 0.05), as well as that taste sensitivity decreases with age, especially after 50 years old (all tastes; p values < 0.05). These findings strengthen our knowledge about the influence of sex and age on taste sensitivity, and they provide knowledge on the influence of consumption habits related to hot drinks on taste sensitivity.

Characteristics of Non-Ablative Resurfacing of Soft Tissues by Repetitive Er:YAG Laser Pulse Irradiation

Background and Objectives

Recently, several minimally invasive gynecological, ENT and esthetic procedures have been introduced that are based on delivering “smooth” sequences of Er:YAG laser pulses to cutaneous or mucosal tissue at moderate cumulative fluences that are not only below the ablation threshold but typically also do not require local anesthesia.  To explain the observed clinical results using “smooth‐resurfacing,” it has been suggested that in addition to the direct heat injury to deeper‐lying connective tissues, there is an additional mechanism based on indirect triggering of tissue regeneration through short‐exposure, intense heat shocking of epithelia. The goal of this study is to improve understanding of the complex dynamics of the exposure of tissues to a series of short Er:YAG laser pulses, during which the thermal exposure times transition from extremely short to long durations.

Study Design/Materials and Methods

A physical model of laser‐tissue interaction was used to calculate the temperature evolution at the irradiated surface and deeper within the tissue, in combination with a chemical model of tissue response based on the recently introduced variable heat shock (VHS) model, which assumes that the tissue damage represents a combined effect of two limiting Arrhenius′ processes, defining cell viability at extremely long and short exposure times. Superficial tissue temperature evolution was measured during smooth‐resurfacing of cutaneous and mucosal tissue, and compared with the model. Two modalities of non‐ablative resurfacing were explored: a standard “sub‐resurfacing” modality with cumulative fluences near the ablation threshold, and the “smooth‐resurfacing” modality with fluences below the patient′s pain threshold. An exemplary skin tightening clinical situation was explored by measuring pain tolerance threshold fluences for treatments on abdominal skin with and without topical anesthesia. The obtained temperature data and pain thresholds were then used to study the influence of Er:YAG laser sequence parameters on the superficial (triggering) and deep (coagulative) tissue response.

Results

The simulations show that for the sub‐resurfacing modality, the parameter range where no excessive damage to the tissue will occur is very narrow. On the other hand, using pain tolerance as an indicator, the smooth‐resurfacing treatments can be performed more safely and without sacrificing the treatment efficacy. Two preferred smooth‐resurfacing treatment modalities were identified. One involves using optimally long pulse sequence durations (≈1–3 seconds) with an optimal number of pulses (N ≈ 10–30), resulting in a maximal short‐exposure superficial tissue response and moderate coagulation depths. And for deeper coagulation, without significant superficial heat shocking, very long pulse sequences (>5 seconds) with a large number of delivered pulses are to be used in combination with topical anesthesia.

Conclusions

A comparison of the simulations with the established smooth‐resurfacing clinical protocols in gynecology, ENT, and esthetics suggests that, through clinical experience, the clinical protocols have been optimized for the maximal superficial heat shock triggering effect. Further research is needed to gain a better understanding of the proposed role of heat shock triggering in the clinically observed regeneration of cutaneous, vaginal, and oral tissues following Er:YAG laser smooth‐resurfacing. Lasers Surg. Med. © 2021 The Authors. Lasers in Surgery and Medicine published by Wiley Periodicals LLC.

Perceived role of hot food in the pathogenesis of oesophageal cancer: a qualitative study in the Arsi Zone, Oromia, Central Ethiopia

Observational studies in Ethiopia have identified a positive association between hot wheat porridge consumption and oesophageal carcinoma. However, a single dietary intake cannot be a sufficient predictor of cancer among populations that have diverse dietary practices. The present study was carried out to explore the community's perspectives on the role of hot foods in the pathogenesis of oesophageal cancer in Ethiopia. Focus group discussions were conducted from May to August 2019 among purposefully selected 112 participants. Data were collected by using open-ended questions; memo writing, audio recordings and photo pictures. All tape-recorded interviews were transcribed verbatim and inductively coded using Atlas.ti Version 7.0.71 software. Finally, the analysis was performed according to the standard thematic framework analysis techniques. The finding showed that hot foods (porridge, coffee and soup) consumption patterns were perceived as the principal dietary risk of oesophageal cancer. Cooking in unventilated rooms, monotonous cereal-based foods, poor vegetable, and fruit intake, not taking milk with porridge, eating fast, swallowing large bolus of hot porridge and exposure to carcinogens in foods were regarded as predisposing dietary practices to oesophageal carcinoma. Socio-demographic, economic and cultural backgrounds were reported as the underlying risk factors associated with oesophageal cancer. There was a strong perception within the community that oesophageal cancer is linked to several but sequentially interlinked dietary and related practices. Cumulative thermal injuries from the consumptions of hot food could be the immediate dietary risk factors associated with increased risk of oesophageal cancer.

Influence of the Brewing Temperature on the Taste of Espresso

Very hot (>65 °C) beverages such as espresso have been evaluated by the International Agency for Research on Cancer (IARC) as probably carcinogenic to humans. For this reason, research into lowering beverage temperature without compromising its quality or taste is important. For espresso, one obvious possibility consists in lowering the brewing temperature. In two sensory trials using the ISO 4120:2004 triangle test methodology, brewing temperatures of 80 °C vs. 128 °C and 80 °C vs. 93 °C were compared. Most tasters were unable to distinguish between 80 °C and 93 °C. The results of these pilot experiments prove the possibility of decreasing the health hazards of very hot beverages by lower brewing temperatures.

A Review of Hot Beverage Temperatures-Satisfying Consumer Preference and Safety

Hot beverages are served ubiquitously in the food-service industry as well as at residences and other venues. Coffee and tea beverages, in particular, are brewed at temperatures that are sufficiently high to cause immediate and serious risk for scald injuries. On the other hand, numerous research studies have been performed to identify the preferred consumption temperatures for hot beverages. The outcome of these mutually reinforcing studies is that the preferred drinking temperatures are significantly below the often-encountered brewing temperatures (∼200 °F). Consequently, there is great need to distinguish brewing temperatures from serving temperatures. Serving consumers beverages at very high temperatures is not only unnecessary (from a preference standpoint) but also unsafe. An appropriate range for service temperatures is (130 to 160 °F). PRACTICAL APPLICATION: Often times, hot beverages are served at temperatures near their brewing temperature; far hotter than preferred by consumers. This practice creates unnecessary risk to the consumer. A more rationale recommended range of service temperatures is 130 to 160 °F. This recommendation balances a range of consumer preferences and safety.