High-pressure processing (HPP) is a novel technology for the production of minimally processed food products with better retention of the natural aroma, freshlike taste, additive-free, stable, convenient to use. In this regard safety of products by microbial inactivation is likely to become an important focus for food technologists from the research and industrial field. High pressure induces conformational changes in the cell membranes, cell morphology. It perturbs biochemical reactions, as well as the genetic mechanism of the microorganisms, thus ensures the reduction in the microbial count. Keeping in view the commercial demand of HPP products, the scientific literature available on the mechanism of inactivation by high pressure and intrinsic and extrinsic factors affecting the efficiency of HPP are systematically and critically analyzed in this review to develop a clear understanding of these issues. Modeling applied to study the microbial inactivation kinetics by HPP is also discussed for the benefit of interested readers.

High Pressure Processing (HPP) is a well‐established nonthermal technology for ensuring microbial safety and nutritional quality of foods. Ascorbic acid (AA) is highly labile antioxidant, susceptible to degradation when exposed to oxygen, change in pH, temperature, or pressure. Preservation of AA in fruit and vegetable products is a prime concern for food processors. This review summarizes recent data on the effect of HPP on AA content of different fruits and vegetables, and their products. In most of the food products, HPP has supported either preservation or better retention of AA after pressurization (400–600 MPa/5–10 min) at lower or room temperature. High pressure processed foods have demonstrated better stability of AA during refrigeration storage as compared to thermally processed ones. These studies establish the positive implications of HPP and justify its potential use as a promising preservation technique to safeguard AA in food products.

T he World Health Organization classifies maternal deaths due to traffic crashes as coincidental and not related to the state of pregnancy. Others have argued that pregnancy is the root cause of such deaths, because pregnant women are more susceptible to crashes. In a linked CMAJ article, Redelmeier and colleagues 1 report intriguing findings from a Canadian population-based study showing an excess risk of serious motor vehicle crashes during the second trimester of pregnancy compared with the risk before pregnancy. The study design is novel because the researchers used data from before pregnancy to use women as their own controls. The study also makes clever use of medical billing data routinely collected in Ontario with linkage to registries that supply data on socio demographic characteristics and to the Canadian Community Health Survey for data on lifestyle factors. These robust methods address many of the flaws in previous research on the same topic. However, as with all observational studies, it is difficult to make causal inferences. In this article, we assess the associations shown in the study in light of the criteria proposed by Hill: 2 temporality, consistency, biological plausibility and evidence of a dose-response effect.Redelmeier and colleagues satisfy Hill's temporality criteria because the exposure (pregnancy) precedes the outcome (serious motor vehicle crash). Moreover, the study's findings are consistent with the findings of previous research. A population-based study from North Carolina found that the highest risk of a motor vehicle crash during pregnancy occurred at 20-31 weeks' gestation, with a marked de cline in the risk of a crash thereafter, 3 which is similar to the current study's results. A decline in the risk of a motor vehicle crash among wo men in their last trimester of pregnancy could be explained by reduced numbers of women driving during the third trimester. A population-based casecontrol study that examined the association between birth defects and crashes among pregnant women also found that crashes were highest during the second trimester of a pregnancy. 4 Examination of biological plausibility requires a discussion of the effects of normal physiologic adaptations of pregnancy that allow for the growth and survival of the fetus and ensure survival of the mother. Driving requires a high level of concentration and cognitive ability to maintain and complete a number of complex tasks. If there is any impairment in the driver's cognitive ability, there may be an increased risk of a crash. 5 The physiologic changes of pregnancy have been shown to increase fatigue and sleep deprivation in pregnant women. 6 A prospective study using self-reported questionnaires showed that sleep length began to decrease during the second trimester and quality of sleep worsened during pregnancy. 7 Maternal stress is also a common feature of pregnancy. Exposure to everyday stressors through individual, societal and familial factors may encourage a physiologic response triggering negative maternal and...

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